Scott's Feb 2007

Mid-Atlantic Radar

Scott's February, 2007 Blog
(blog descends chronologically)

Severe Outbreak To Include Winds and Violent Tornadoes Tonight & Thursday...
Snow to the North And Then Heavy Rain To The Mid-Atlantic.
Wednesday, February 28

Good riddance to February, what a dreadful month this has been! Unfortunately, March will begin in much the same fashion.

Another midweek storm is rolling out of the Rockies to crank up over TX./OK and head into the Midwest. Heavy snow well to the north of the developing system but strong tornadoes possible tonight in Missouri and Arkansas. Night time tornadoes are especially dangerous and persons in these areas must be vigilant tonight as it is unlikely storms will weaken overnight!.

This discussion will focus on Thursday-Friday dangers. This afternoon's MODERATE Risk area from SPC is stunning:

Surface Low Pressure swings out as a trof comes across the Nation's midsection, pulling copious moisture out of the Gulf and rushing well inland ahead of the storm. You know the drill: warm moist air ahead of colder air streaming in as the Low spins counter clockwise will produce violent weather. STRONG, LONG LIVED TORNADOES ARE POSSIBLE and portions of the Moderate Risk area may go to a dangerous and rare HIGH RISK on Thursday! Violent tornadoes are expected overnight into Thursday midday from Arkansas into Illinois. Strong winds, hail and tornadoes could traverse east toward the Ohio Valley, western Tennessee Valley...perhaps across the Gulf Coast States (except the FL Peninsula) and up through GA and the Carolinas by Thursday night.

Rain, perhaps heavy at times, makes it to the Mid-Atlantic States where departing High Pressure will help keep a lid on severe weather...but...thunderstorms and downbursts are possible up into SE Virginia Thursday evening. At the moment, numerous Flood Watches are posted north of the Mason-Dixon Line, in part to current snow depth and ice on rivers and streams. Flood threat lower across the Mid-Atlantic because there's less snow to met and run off with the upcoming rain.

Cooler air will be reinforced by the storm and will produce snow into Friday over the U.P of Michigan, Upstate NY and north of the Mass Pike in New England. Backlash snow will accumulate several inches on the Alleghanies and over central PA. Southern New England could see a wintry mix and mess late Thursday into Friday morning.

We'll have another discussion update here on the blog on Thursday morning. Rapid-fire updates will appear on our RSS news feed. Folks up north can stay current by visiting our Winter StormCenter. Others, including the Mid-Atlantic area should keep an eye on developments at our Severe WeatherCenter for current warnings and information.

Rough night tonight and a particularly dangerous day on Thursday for locations in and near the red Moderate Risk box above.

"The Big Show" Brings Winter and Tornado Threats to The East.
Sunday, February 25

Low Pressure over Iowa this morning is pushing a Warm Front to the Southeast to South Carolina. The frontal boundary will become Stationary over North Carolina; blocked by High Pressure to the north that is keeping cooler air wedged into Virginia.

Current temperatures (click to enlarge):

I have no major changes this morning to the general forecast presented in yesterday's discussion. This is an extremely complex event with miniscule temp changes altering precipitation types but overall:

SNOW: Generally from along and near Rt.17 across the Southern Tier of NYS to the PA Tpke and perhaps as far east as Bergen County, NJ and NYC. Looks like the 12Z NAM (coming in now) pushes the snow a bit further north so we'll monitor that possibility). Snow totals in the 3-5 inch range, dependant on if/when freezing rain mixes in. Poconos, eastern PA.

FROZEN: Northern Ohio Valley...western and southern PA should go from wet snow to mostly freezing rain (some pockets of ice pellets). Most of NJ and the upper Delmarva should be a winter mix of freezing rain to rain. Freezing rain is expected to stay north of VA I-64 and west of the I-95 corridor. Western MD, eastern MD and the I-81 corridor down to Lexington or Roanoke will hover near or just above 32° and sleet/freezing rain/rain is expected to continue into the afternoon...a change to drizzle or light freezing rain likely tonight.

RAIN: South of VA I-64 and west of the interior mountains to north central Florida.

Across the Mid-Atlantic, precipitation wanes from southwest to northeast tonight and Monday morning. Freezing rain/drizzle hangs tough up the I-81 corridor, north of Harrisonburg, VA, along northern Blue Ridge, over NOVA, most of MD and central-eastern PA (where there's potential for another snow to freezing rain nightmare). By midday Monday temperatures will be above freezing for virtually all locations south of the Mason-Dixon Line.

SEVERE: Strong thunderstorms possible today east of a line from Norfolk, VA to Tallahassee, FL with damaging winds being the greatest threat. Large hail may develop in severe storms south of Wilmington, NC. Supercell development and isolated tornadoes are possible. This threat would increase tonight if Low Pressure spins up along the Stationary Warm Front and gets cranking off the NC/VA coast. Please visit our Severe WeatherCenter for current warnings and information.

Next update here on the blog at 5PM.

UPDATE 5:00PM: The Big Show now centered near Chicago is weakening as a new coastal Low pops over eastern NC (as discussed in earlier post this morning). For the Mid-Atlantic...precip now lifting to the Northeast however some freezing drizzle will persist as the coastal storm organizes. Temps are generally at or above freezing and should not drop a great deal overnight as this system will push warmer air inland...helping to keep temps from dropping much at night. Slippery spots will continue however the bulk of precipitation now is pulling away.

Some rain/freezing drizzle may creep up from TN/WV and Extreme SW VA but should not cause much trouble before weakening if it clears the Blue Ridge Mountains tonight. Worth a mention because this may put a slight glaze on roadways.

SEVERE: Severe Thunderstorm Watch through 9PM from SE NC to Savannah, GA. Wow! Ample wind shear may really get some storms going in this area early this evening! Can't rule out an isolated tornado...however...bigger threat is from large, damaging hail. Check into our Severe WeatherCenter for current information.

"The Big Show" Is Here. Tornadoes and Snow Today...
Severe Weather And Ice Tomorrow.
Saturday, February 24

Low Pressure over Oklahoma produced tornadoes last night from TX Panhandle to SW Kansas. The storm will intensify today, producing everything from near blizzard conditions to the northwest, to a wintry mix of freezing rain and snow approaching Chicago. Thunderstorms, Supercells and tornadoes over the Lower Mississippi Valley. Greatest risk for tornadoes today remains LA, AK and MS:

My hunch is the Moderate Risk area will include more of AK, OK and TX this afternoon. Severe thunderstorms also expected to develop today over western OK and move into AK. In fact a PDS (Particularly Dangerous Stuation) Tornado Watch is up for that very area. Current info at our Severe WeatherCenter.

Shreveport, LA Radar and Warnings HERE.

Everything moves east on Sunday, shifting the severe threat to AL and north-central FL (again) up into the Carolinas. Storms aren't expected to be as strong tomorrow as today, however convective lines will develop to continue the danger of strong winds and tornadoes.

Mid-Atlantic north of the NC/VA border is a very tricky call. Temps will moderate today as warmer air begins transport over the Mid-Atlantic. High Pressure slides east and develops a CAD (cold air damming) situation for much of Virginia. This cooler air dammed up east of the mountains will be overrun by warmer air aloft, being pumped in by The Big Show...resulting in a a high probability of a freezing rain event north of the NC/VA border on Sunday.

The 12Z NAM pushes freezing rain into VA north of the I-64 corridor on Sunday morning with a change to rain by late afternoon (NOVA remains wintry mix). Mostly rain south of I-64, east of the Blue Ridge. Air Force MM5 (which I like for east coast winter weather) starts overnight as snow west of the Blue Ridge with freezing rain to rain north of I-64...plain rain to the south. It is slightly colder than the NAM. The 12Z GFS is just coming in now but looks a tad warmer than the 00Z. The RUC (Rapid Update Cycle) model comes into play this afternoon. Because of my current hectic schedule and extensive driving I've not examined all the other models.

At this time I'll stick with previous ideas presented here: rain gets into Mid-Atlantic overnight. I-81 corridor along the Blue Ridge north of Roanoke should see rain change to freezing rain...possibly with slight accumulations of wet snow/sleet (but not if the NAM is correct). Freezing rain is possible through the afternoon, producing another day of black ice driving. East of the Blue Ridge to I-95: wet snow/sleet with little if any accumulation changes to freezing rain. Marginal temps should help a changeover to plain rain by Sunday afternoon along and east of I-95, south of NOVA. Looks like all snow will be limited to the Southern Tier of NYS (along Rt. 17) down into south central PA where several inches may accumulate. East of this area, a snow/sleet and freezing rain mix looks likely. Biggest problem with the scenario is how bad will the roads be from NOVA up the I-95 corridor...right now it looks nasty from Philly into Metro NYC on Monday morning.

Check local forecasts and get updated at our Winter StormCenter.

Not sure if I'll be able to have another discussion tonight (please read below); if not, I will update our news feed.

Partly Personal: I've received several thoughtful emails regarding our family friend involved in a serious accident last Wednesday on I-81 (more in 2/22 blog). I've been unable to respond to most mail but I am grateful and thankful for your comments. Our good friend has made it through the "first 48" hours and remains fully immobilized, on a respirator, can't talk and has undergone 17 hours of surgery in less than 72 hours. She does recognize family and friends permitted to briefly visit her; what a blessing! Where there is hope, there is life. Available time for posting here on the web site remains at a premium but I'll try to keep the blog current on this weather event. While on the road it is possible to post updates on our RSS news feed so I hope you'll check in there as well. Thanks.

Potentially Dangerous Mid-Atlantic Wind Event Before
"The Big Show" Invades The Central/Eastern US With Widespread Severe Weather.
Thursday, February 22

Brief post (see comments below). Clipper is bringing a sharp cold front across the region and very strong winds are now increasing across the region. At our weather station we've observed sustained 25-35MPH winds with gusts to 47MPH gust. Wet snow showers likely along western slopes of Alleghany Mountains and up through the mountains of PA. North of this area, ideas previously presented seem valid: a stripe of snow, likely less than 4 inches, from Erie, PA to around Portsmouth, NH. Rain to snow later today near/east of I-95 corridor from NYC up into southern New England.

This is a significant wind event for the Mid-Atlantic and portions of the Southeastern US! difficult driving, downed limbs and a renewed threat of power outages are all possible, if not likely. Check our Severe WeatherCenter for real-time information.

SEVERE: The Big Show is coming. Low Pressure gets cranked near Oklahoma heads ENE, impacting most of the US east of the Rockies. Gulf of Mexico is opened for business with huge moisture transported up with thunderstorms, hail and some tornadoes kicking off the Big Show tomorrow from central Texas into south-central Kansas. Potent storms will migrate east on Saturday, with snow north of the storm track (High Plains-Upper Midwest) and severe weather tracking into the Mississippi and Tennessee Valley on Saturday. Will be interesting to also see how much winter weather develops near the Great Lakes...something to follow and discuss in a future blog.

Severe weather stays south of the VA/NC border. As always, big storms along the Gulf Coast states may limit rain and winter potential on Sunday into Monday for the Mid-Atlantic area...but rain should be expected. The concern also may be for wet snow or even some ice...possible north of the I-64 corridor in Virginia as well as some areas along the northern Alleghanies. Models still diverse on winter weather north of the Mason-Dixon Line from The Big Show but this complex storm certainly has potential to dump down some snow in the Northeast with mixed precip from VA into PA. Check your local forecast and visit the Winter StormCenter here at Mid-Atlantic WX.com for the latest.

Partly Personal: A family neighbor and very dear friend was seriously injured in a horrific vehicle accident yesterday on I-81. My family and I are doing what we can to help her family and we're making trips to the hospital in Roanoke, VA (65 miles). Suffice to say time is at a particular premium over the next several days, so blog posts may be short. The hope is daily discussions on the upcoming event however I suggest you keep an eye on our new RSS news feed as rapid fire updates may be the best I can do. Your understanding is appreciated. Thanks.

Side Shows Before "The Big Show".
Monday, February 19

First, I should note temps today remain below normal but have warmed up nicely across the region. I note at 3:30PM our wx station has soared to 43° (normal is 50°). This is the warmest it has been here since January 28...23 days ago!

A couple little garden variety events to discuss before The Big Show this weekend. A minor system cuts across the Lakes and zips into the Northeast Tuesday and Wednesday before hitting the North Atlantic. This should produce some rain into the Southeastern States and the Mid-Atlantic...can't rule out a flurry on the north western slopes of the Alleghanies. Light accumulations expected along a line from Erie, PA to Portland, ME; even here nothing over 4 inches is expected.

Another little Clipper invades the Northeast on Thursday, bringing light accumulations from the Lakes into New England. Can't find sensible weather or any model support for more than modest totals (4 inches, maybe).

Advertised Death of the Iceman on schedule this week :) and temperatures should be at or slightly above normal by Wednesday.

THE BIG SHOW: Subtle differences among models but a MAJOR storm is coming this weekend (yes, I am now officially "honking"). This looks to have classic early Spring severe outbreak written all over it. However, the first item I've noted is some computer models are slowing down the development and onset of severe weather, so timing is probably going to be adjusted as the week progresses.

Potent energy comes inland over the Pac NW...you can see this now setting up by clicking HERE. Upper level trof swings in approaches the Rocky Mountains later this week. Low Pressures rolls down off the Rockies and deepens over the Central Plains before tracking toward the Great Lakes. Cold air is sharply divided from warmer air and Gulf moisture comes streaming into the Central US along the boundary between the two different air masses. Thinking right now is strong storms get organized and cranking Friday night over eastern Texas and move to Mississippi Valley and north-central Gulf States on Saturday. Late Saturday and Sunday the action shifts to the Ohio and Tennessee Valleys as well as the southeastern US and Florida. This complex event will feature strong thunderstorms, hail and I am afraid numerous tornadoes. Still have low confidence in forecasting severe weather east of the Appalachians into the Mid-Atlantic...but there is a chance as the Low swings by to the Northwest.

Big weather isn't restricted ahead and south of the storm...northwest of the storm track there will be significant snowfall and strong winds...blizzard conditions could develop over the Upper Plains. Snow and mixed precipitation is also likely for the Northeastern US late weekend into early next week.

Again, timing will need to be tuned up but I don't see how this MAJOR storm event does not happen! Keep an eye on the blog and our new RSS news feed for updates on this major storm.

Windy, Warmer and Wild.
Sunday, February 18

The departing Clipper system has dumped impressive totals over southeastern WV and SW Virginia and the western NC mountains...with some locations topping out in the six to eight inch range. I did see 11 snow flakes this morning but it is a winter wonderland just over in Greenbrier County, WV, where a foot may pile up! Cold Front crossing the Mid-Atlantic today will allow winds to pick up this afternoon and tonight from the Blue Ridge of Virginia to Montgomery, Alabama. This frontal passage opens the door for another fresh batch of cold air to rush into the region on gusty Northwest winds.

While temps will remain below normal today through Tuesday, the brutal core of Arctic cold is weakening and retreating this week!!!

High Pressure slides toward the East and will bring a return to Zonal Flow...winds generally moving from west to east. This coincides with precipitation moving into the region later on Tuesday. Right now, it looks like plain rain form *most* of the Mid-Atlantic...although a wintry mix or some wet snow is possible over higher elevation of the mountains...and perhaps north of the I-66 corridor. I'll keep an eye on this but don't think we'll have widespread winter weather Tuesday night in the area. Interior Northeast may see more snow from this system as there will be cold air at the surface. Please check the blog on Monday afternoon for an update, and I'll keep things current on our RSS news feed.

Warmer air finally overtakes the East beginning on Ash Wednesday and temperatures actually may be a couple degrees ABOVE normal!

SEVERE: Next concern is a storm rumbling over the Rockies and into the Plains late Friday or Saturday. As with all events 5-7 days away, there is great uncertainty but the potential may develop for a significant and widespread severe weather event...at least to the Alleghany Mountains. I don't want to model hug but the GFS continues painting a moderately severe event from Oklahoma across the north central Gulf Coast States and Tennessee Valley. I'll keep an eagle eye on this and we'll certainly discuss this potential event during the week.

Well, the Daytona 500 is today and Major League Baseball Spring Training is getting into full swing and one can certainly hope Spring is not that far away. Next update here at the blog on Monday afternoon.

Coming Clipper And Coming Attractions.
Thursday, February 15

This morning's Short Range Ensemble Forecasts (SREF) show probable track of this weekend's Clipper type storm (click graphic for more maps):

Our departing storm is depicted off the Coast of Maine.

Clipper should not have a great deal of moisture to work with but will push light snow from the Upper Plains south and east, reaching the Alleghany Mountains on Saturday night. Not much juice here but can't totally rule out snow south of the PA Turnpike early Sunday, Not too enthused more than a light wintry mix makes it to Philly before the storm heads out off NJ. Temps will again be below normal into early next week.

Next weather maker comes late next week however the big question for the East will be: white or wet? Medium range models agree with a rising AO Index that bolsters the idea of a warm up around Ash Wednesday. Timing, surface temps (especially in the Northeast) and snow cover all play a role so for now we'll see how developments unfold. Initial thinking is another severe threat for the Deep South, rain Southeast and Mid-Atlantic.

Ice storm in VA took down my connection with Mid-Atlantic WX.com. Prolonged power outage mitigated by back-up power but the Internet was inaccessible, so I was unable to post and the weather station couldn't reach our server. This was the longest power outage I've experienced since remnants of Hurricane Fran ripped through Virginia in 1996. Dreadful to contemplate how dependant we are on accessing the Web.

Tuesday-Wednesday Storm Update #4, #5 & #6
Tuesday, February 13

Folks south of our "famed" VA I-64 dividing line may be wondering if they're getting shafted...again. Nope! First batch of snow over N WV, NOVA and PA is associated with the precipitation behind it over the Ohio Valley and back to Missouri...this continues a west to east track.

Rain over TN Valley moves up into Mid-Atlantic early this afternoon...rain to a wintry mix as you head north across VA. I'll note that the NAM model (pretty good with this storm) is placing the coastal Low quite south (GA/SC) we'll see if it's right or gets corrected on the 12Z run. This is important because it is slightly warmer than the model now depicts right along, into Metro DC and up the coast south of central NJ, so Delmarva and the VA coast should see mostly rain (with pockets of wintry mix).

Our exclusive MesoMap showing current temperatures (click graphic to enlarge):

In locations still to see precipitation, conditions deteriorate this afternoon from Noon-3PM as you head northeast across the Mid-Atlantic. The 12Z RUC is just coming in but shows much the same regarding the timing.

Biggest challenge remains surface temps...many locations south of I-64 and east of the Blue Ridge will see rain with a sleet/freezing rain mix from this event. West of the Blue Ridge down the I-81 corridor remains the same: Hagerstown to Staunton snow and sleet to freezing rain with totals around 2-4 inches with ice. Staunton-Roanoke-Fancy Gap expects some sleet changing to freezing rain with half inch ice accumulation possible.

No changes in earlier ideas here for locations north of Virginia. However, my snow totals may be TOO LOW for the Poconos, the NYS I-88 corridor (Binghamton- near Albany) and interior New England...looks like 12 inches will be the baseline with totals exceeding 14-16 inches!

When the coastal Low (Nor'easter) cranks up off the Northeast coast, just for fun I will post some links to off shore buoys and a couple coastal web cams. This will be a dandy storm to watch from the Nubble Lighthouse or Portland Head in Maine :)

SEVERE: Tornado Watch continues this morning for southern MS into the FL Panhandle. Similar to the last storm...tornadoes may quickly develop along and near southern end of a squall line in the area. Severe weather may shift down the Florida peninsula later today. Stay alert, monitor local information and stay close to our Severe WeatherCenter.

Next update here on the blog will be around 4PM this afternoon. Short-fuse information appears on our new RSS news feed.

UPDATE: 4:40PM: Check our Mesoscale Discussion Map for tornadoes, freezing rain and heavy snow/blizzard comments from the Storm Prediction Center. And some people wonder why I have a fascination for wild weather?!

Precip a little behind schedule south of VA I-64 but Radar is filling in and overall thinking remains unchanged. Mostly rain east of I-95 south of Metro DC. Rain/sleet to moderate freezing rain west of I-95, north of the NC/VA border. Wet snow/sleet totals may reach 3 or 4 inches possible western MD, NOVA and I-81 corridor from Hagerstown to Harrisonburg or Staunton, VA. Lesser snow/sleet down I-81 to NC border.

Status Report: Primary Low now over central Tennessee/Kentucky...this is the main player until overnight. Secondary (coastal) Low *appears* to be developing off Georgia at this time. You can get a close-up by using our Hurricane Center satellite animation of the Southeast US/Western Atlantic by clicking here.

IF this is where the Low develops it probably comes inland WEST of Cape Hatteras. First impact is strong winds across eastern NC and VA overnight and Wednesday. Not sure how far west the track gets...probably between I-95 and the coast before crossing the Chesapeake and heading into New Jersey. Need to watch this overnight but a track right along the coast or just inland equals rain and interestingly, there are now Flood Watches for portions of Delaware and New Jersey!

Tornado Watches, Severe Thunderstorm Watches, Blizzard Warning, Ice Storm Warning, Wind Advisory and Flood Watch...wow...this IS an impressive and complex storm! And, it is hard to believe how cold it has been only to now have a February "monster" storm with a Flood Watch. Talk about a Valentine's Day Massacre for snow lovers! Something screwy always happens around the third weekend of February.

There remains serious concern about a widespread icing event for Virginia tonight and Wednesday morning. While driving on I-81 today I passed a Dominion Power convoy of eight utility trucks enroute to a staging area; utility companies are taking seriously the threat of downed limbs, lines and power failures. Add the anticipated strong winds and things can go bad in a hurry.

Right now, I can't get into all the implications north of the Mason-Dixon Line but this is going to be a prolific snow producer inland from the Poconos through interior New England. Folks up there should monitor local media and forecasts but there will be locations exceeding 20 inches of snow when all is said and done.

SEVERE: New SC Tornado Watch roughly from Savannah, GA to Charlotte, NC...includes Charleston.
This line of storms is strong and producing extensive lightning. Again I caution convective storms OFTEN rob the Mid-Atlantic of moisture! I'll be watching the RUC model and awaiting tonight's 00Z runs to see if QPF (precipitation totals) begin to drop for the Mid-Atlantic States. Very complicated scenario we are nowcasting.
A tornado hit New Orleans, damaging dozens of homes. One elderly woman was killed when her home was struck by the twister. Unfortunately, she was still residing in a FEMA trailer, awaiting repairs to her "real" home severely damaged by Hurricane Katrina. How terribly sad.

Keep an eye on our RSS news feed for quick comments. Another post here at the blog by 11PM tonight.

UPDATE: 10:15PM: I usually only write three updates right before a landfalling tropical storm or hurricane so it has been a busy day. Depending on where the coastal Low tracks, it may almost seem like a tropical storm along the Mid-Atlantic and Northeast coast!

Freezing rain continues to expand over much of western and central VA, roughly west of Rt 29 (Wash-CHO-LYH-Danville). Frozen precip should advance east toward the I-95 corridor but south of DC, temps to the east generally are above freezing...with mid-upper 40's near Norfolk-VAB. Richmond is several degrees cooler than forecast for tonight but winds from the southeast should help to keep temps above freezing.

Precip should wane slightly from west to east overnight with temps dropping slightly west of I-95 and holding steady or nudging up a bit close to the coastline. As the coastal Low approaches the Mid-Atlantic winds will shift out of the north/northwest and begin to howl (click here for current advisory information). There could be some snow flurries over the Alleghany Mountains and perhaps the Blue Ridge but I'm not expecting any accumulation. Beware of gusts exceeding 50MPH, especially over higher elevations Wednesday afternoon. Still not sure on exact track but looks like it will track WEST of Cape Hatteras then head out at Newport News/Norfolk, staying right along the coast. This will help pull in warm air inland near the ocean but could help increase snow production to the north and northwest. This will be updated in the morning.

Southeast US buoy data here.

Storm reports for today here.
Quite a noisy night along the Gulf and into the Southeastern US...precipitation (QPF) totals down slightly in the 00Z NAM compared to the 18Z NAM. Thunderstorms to the south near the Gulf are always a wildcard for Mid-Atlantic precipitation, so we'll see if tonight's action did indeed rob some moisture from the Mid-Atlantic. Precipitation should start up anew on Wednesday as the secondary Low takes over and crosses the region.

Let's see how many power outages this storm produces!
Virginia (Dominion)
More VA, PA, WV, MD (AEP)
Metro DC (Pepco)

Next update on the blog will be Wednesday morning. Have a good night.
.

Tuesday-Wednesday Storm Update #3
Monday, February 12

No big changes to announce, so perhaps this will be brief. The GFS model has swung over into the NAM's camp and there's now good agreement on the precipitation types. I will note seeing extensive NAM bashing on the weather boards, however, from 36 hours in, it has had the right idea for the last two events.

Low Pressure over TX will head toward WV (or perhaps NC) when a secondary Low pops up off the SC/NC border and heads up the coast. By the way, the advancing boundary is already prompting Severe Thunderstorm and Tornado Watches for E TX along with AK and LA. One aspect of my earlier forecasts last week was dissing the idea of a Nor'easter...that appears incorrect and we'll have one screaming up the coast on Valentine's Day. It's Bombs Away for the coastal storm as it gets up near the Cape and the Gulf of Maine...strong winds and snow totals exceeding 12-15 inches are possible for the interior Northeast.

The primary Low is expected to dump a stripe of 5 to 8 inches of snow from Iowa, across the Ohio Valley and southern PA...with Upstate NY again getting pummeled with 10 inch plus snowfall buffeted by gusty winds (I *knew* there was a reason I moved from NY!).

A little trickier to the south from say Gettysburg to Philly and eastern MD. Warm air will stream in as the primary Low approaches and the question becomes how long does cold (sub freezing) air hold on at the surface. Until warm air fully works into locations south of VA I-64, it looks like a mix of rain/wet snow/sleet will dominate with little accumulations (an inch or less). Don't be surprised to see nothing new on the ground Tuesday morning! North of I-64 through NOVA, W MD and the Eastern Shore a little more snow may mix in; this is also reflected in the 18Z NAM and the 21Z RUC. Thinking right now is warm air aloft scours out cold air at the surface and rain/freezing rain predominates locations near and east of I-95, south of Philly.

Significant icing is likely along and near a line from Blacksburg, VA-Washington DC-Paramus, NJ...making for black ice roads and raising the possibility of downed limbs and power failures. Lesser amounts of freezing rain are to be expected along the I-95 corridor from NYC to Philly, as well as most of VA (excluding SE locations where more plain rain is expected). Check your local forecast by typing in your zip code at the top of any page on the web site. Get real-time warning information at our Winter StormCenter.

As the coastal Low cranks up the coast a new batch of cold air wraps in behind the storm and this will help Big Dog snow amounts in the Northeast. For the Mid-Atlantic, this has the effect of cooling air near the surface, so freezing rain and drizzle should continue well into Tuesday night and Wednesday morning when a little wrap around snow spins around PA and the Alleghanies. I spoke to a Virginia State Trooper today (no, I wasn't pulled over) and he said the agency has been told to expect: "a good-ole fashioned North Carolina ice storm for much of NOVA, central Virginia and the Shenandoah, Roanoke and New River Valleys". Think that's probable.

SEVERE: Visit our Severe WeatherCenter for current info on developing weather from east Texas and Louisiana. Strong storms move east tonight into Mississippi and they advance toward Florida on Tuesday. Take seriously any warnings...especially tonight! We'll watch this line of storms tonight and tomorrow for severe weather as well as sniffing out any moisture being "robbed" from the Mid-Atlantic area. Another area of concern for storms is coastal SC and NC up through Wilmington...yet another facet of this immense storm system to ride herd on over the next 36 hours.

Updates and tweaking tonight will be handled on our new RSS news feed.I'm working on setting it up so you can post a comment or question...so check there tonight. Link is to the left or click here. Next full discussion here at the blog on Tuesday morning.

Lastly, our server is getting slammed with traffic and is slow tonight. Typically, this only happens before landfalling hurricanes or tropical storms so please bear with us and THANK YOU for letting us bring you important information on this major winter storm!

Tuesday-Wednesday Storm Update #1 and #2
Sunday, February 11

There were problems with the 00Z runs last night so I postponed a brief blog until reviewing the 6Z models this morning and watching the 12Z runs come in.

GFS and NAM from 6Z this morning (click graphic for more maps):

NAM (blue line) depicts Low coming up west of the Appalachians and this would produce more of a wintry mix for Mid-Atlantic (read: less snow). A secondary Low pops just off the VA/NC coast, intensifies and heads up the coast. I think the NAM is too close to the coast but may have the right idea. However, the 12Z NAM is further south than the above model map shows so this is far from a done deal. These storms are why my gray hair doubles monthly! We are getting within range of including the MM5 and RUC models and I'll certainly need to update the blog later tonight. It is clear that warm air streams in ahead of the Low and Monday will be the only day of near normal temperatures for the region...this also means the precipitation begins as rain south of the VA I-64 corridor (Staunton-Charlottesville-Richmond-Norfolk)

Winter Storm Watches already up for portions of Ohio Valley and Mid-Atlantic as the storm gathers steam today over the Plains and heads east. ALERT: strong to severe storms possible tonight through Tuesday along the Gulf Coast from Texas to Tampa and Jacksonville, FL! Recall the recent Florida TORs resulted from severe wx associated with a winter storm to the north! Yes...there may be Supercells with this event so folks along the coast and N-C Florida need to closely monitor conditions.

Right now for the Mid-Atlantic it appears plain rain is coming south of central Tennessee and North Carolina up to Norfolk-Virginia Beach, VA. North of this line up through the lower Ohio Valley to Delaware I think there will be mixed precipitation and accumulating snow. The concern is how much how much before backlash snow then piles for this area as the secondary (coastal) Low spins up. Very good chance for Big Dog snowfall for PA, western MD, WV and near the Alleghany Mountains...not so sure about NW North Carolina with this storm. I can't give you amounts with any credibility right now because:

- we don't know where the Low will develop and then track.

- it is unknown how strong convective storms will be along the north central Gulf Coast and Florida (strong
storms often "rob" precipitation from the lower and central Mid-Atlantic.

- potential dry slot for area may quickly shut down precipitation between primary and secondary storms.

Also, for Mid-Atlantic, this may come in pieces with the primary Low affecting the region late Monday into Tuesday before the secondary (coastal) Low cranks up Tuesday night and Wednesday.

I do believe much of the Ohio Valley, PA, NYS and New England get hammered with a significant ALL SNOW event (except along and east of I-95 south of Portsmouth, NH). A lot of Valentine's Day dates will be postponed in the Northeast!

Please check back after 9PM tonight as I'll update the blog with the 0Z models. Our news feed will update throughout this event (link on left side of page).

UPDATE 9:35PM: As suggested this morning, the trend continues toward less snow *south* of the Virginia
I-64 corridor (Staunton-CHO-RIC-NOR).

Current Water Vapor Loop of the Eastern US shows system pulling over the Plains (click graphic for more views):

This now appears a mostly rain event for NC/SC, with the possibility of some sleet briefly mixing in over central-northern NC. Monday's highs will exceed the freezing mark for much of the region and precip should begin as rain. The challenge is determining where evening temps and highs on Tuesday drop below freezing, despite warmer air in the mid-levels. And the issues noted earlier remain: do Gulf/Florida thunderstorms rob the Mid-Atlantic of moisture...and where is the coastal Low forming and tracking? I'm concerned the Subtropical Jet diving across the Gulf and crossing Florida could enhance convective activiity meaning more severe weather there...less precipitation up in the Mid-Atlantic. This needs to be monitored on Monday.

Even with fluctuations in model runs locating the coastal Low, I think a solid stripe of 4+ inches snow goes from Illinois to Ohio with some sleet and perhaps a little freezing rain or drizzle with slight accumulations over Kentucky. Right now, West Virginia should see widespread 4+ inch totals by Wednesday.

And now...back to the VA I-64 corridor. Most of VA south of this line is rain to sleet (slight accumulations possible west of I-95. North of I-64, the rain/mix should change to snow, especially WEST of I-95 as one heads up the Interstate from Richmond. For the Shenandoah/Roanoke and New River Valley: sleet/snow from Winchester to Harrisonburg-Staunton, more sleet than snow from Staunton to Roanoke, sleet/freezing rain from Roanoke to Fancy Gap.

3-5 inches of snow/sleet mix possible for Metro DC unless warm air holds at the surface...then a couple inches are likely.

As one crosses the Mason-Dixon Line, the cold air will hold tougher and SIGNIFICANT snowfall amounts are probable across much of PA. If the NAM model is right and the coastal Low hugs the coast ala a Nor'easter, PA could see widespread totals exceeding 8 inches! NJ and Metro NY will see some accumulation but a wintry mix is expected to keep totals much lower than inland over PA. Upstate NY along and east of I-88, as well as interior New England should "take a thumpin' " with some areas seeing a foot or more snow by Thursday.

My area of lowest confidence remains Virginia, Delmarva, and the Metro areas of Washington, Baltimore and Philly...need to tune up this forecast on Monday. However, several models (including the NAM and the MM5, both of which were pretty good within 36 hours of the last storm) bring in sufficient warm air to knock down much hope for snow over the southern half of VA and all of the Carolinas.

Again, I'm concerned about storms along the Gulf and Florida as shear and lift should be sufficient for Supercells and tornadoes on Monday afternoon/night and again on Tuesday. Obviously, this is a danger to that area and also can really gum up how the models determine how much precipitation gets into the Mid-Atlantic. Visit our Severe WeatherCenter for threats along the Gulf and be alert for Severe Thunderstorm or Tornado Watches!

I'm a little later than planned tonight. A retired colleague of mine who resides near me lost his home and all its' contents today to fire. Family is okay physically, everything else is gone. Devoted some time today to that tragedy. Next post here at the blog will be Monday afternoon.

Clipper Snow Stays A While, But This Cold Is Getting Old!
And: "Thank You Sir, May I Please Have Another?"
Wednesday, February 7

Our Clipper is now long gone after leaving impressive totals for this type of storm. Our snow depth map should be updated this afternoon...please visit our Winter StormCenter and select a State to see depth totals.

Here's the deck and backyard at my house in Lexington, VA, where five inches accumulated:

Fluffy snow made it easier to "broom" the vehicle and driveway (BTW, you should be able to decipher my license plate!):

A Cold Front is moving SE across the region and temps will stay cold...and drop this afternoon. Check your barometer and you'll see how High Pressure is building into the region and with it, gusty winds.

Next important feature will be the Polar Jet retreating *slightly* to the North, so temps will moderate but remain near/below normal later this week and into the weekend. This means will be be cold...as opposed to frigid.

HEADS-UP: I'm sniffing out some trouble next week...probably around Valentine's Day. Models continue to indicate a storm comes up from the SW, crosses the Gulf States and heads up. I can't "honk" about a storm one week away but the set up looks as though we'll have some weather the middle of next week. Several models flip back and forth this far in advance, but the synoptic set up should be there for a storm. Questions obviously are storm track and temps. Right now I am dubious of any warm up, especially Virginia and points north so I look askew at any model (GFS) that jumps from run to run. If this Low does develop as I believe it will, the other key is location of High Pressure to steer/block the track. Lots of options at this time from a Southern Soaker out to sea to a bona fide Nor'easter.

Meanwhile, I've received happy emails this morning from snow lovers, so I hope you enjoy the white stuff! If you have pictures you care to share, please send to: weather@midatlanticwx.com and we'll include in our Winter Photo Gallery.

Coming Quick Clipper Could Kick In Some Snow.
Monday, February 5

Arctic cold currently is pouring it on...hi temp at our wx station today was 21° which is exactly 25° below normal. At 11pM the temperature is 7 with a dew point of 13 degrees below zero. This is cold, dry arctic air! Winds are light but pushing wind chills below zero as seen here (click graphic for more info):

Despite the bone dry air, it looks as though the approaching Clipper will bring sufficient moisture for a band of snow on Tuesday into early Wednesday morning. Looks like best coverage will be south of Chicago (losers in the Super Bowl, across Indianapolis (winners of the Super Bowl), across West Virginia and perhaps over the Blue Ridge of Virginia. Despite missing the Lakes (from where Clippers often juice up), several inches, especially in snow bands will fall up to the western slopes of the Appalachains by Wednesday morning. East of the mountains I'd doubt more than a couple inches accumulates given the length of time it will take to moisten up the atmosphere. But, higher elevations (such as the Highlands and foothills could top out with 4 or 5 inches of snow. Extremely cold and dry air assures this will be an all snow event with high liquid to snow rations...producing very fluffy dry snow.

Flurries cross the Appalachian Mountains by dinner time on Tuesday, spreading into the Metro DC area...and perhaps the Piedmont in the evening. System is gone by late Wednesday afternoon, the cold will hold into next week. One thing that concerns me is the GFS has been rock solid with this Clipper and produces half inch liquid totals up to WV. High snow rations (15 or 20:1) could really pile up on folks in prolonged snow bands, so it is possible there could be narrow stripes of 6 inch plus accumulations! Keep an eye on this at our Winter StormCenter. Again, following the GFS, eastern KY and southern WV could, as the President would say: take a thumpin'! On the other hand, the 0Z GFS is printing out a bit lower total precipitation as the Clipper nears the Appalachians. Either way, I think there will be accumulation at least to the I-81 Corridor and along I-66 into DC and BAL. Those of you east of the mountains and up into the Philly area will need to keep hope alive.

On-The-Scene Update From Florida Tornado
Sunday, February 4

Cold Comments: Arctic cold is the theme for the week! Guidance indicates temps 20° below normal and 25+° below normal closer to Canadian border. Wind chill values in may areas will border on dangerous...please take precautions. Otherwise, Tuesday Clipper will encroach very dry air and I doubt much snow will fall. There remains a threat for next weekend however temperatures will begin to moderate and we'll monitor developments here at the Blog.

FLORIDA TORNADO UPDATE: Friday we brought you a quick first person account from the disaster area (comments in Friday, February 2 blog). I'm grateful for receiving another update from these folks and share their comments here. But first, a comment: we must develop new ways of notifying people in advance of civil emergency, whether it be natural (weather) or man made (accident/terrorism). Tornado Warnings were issued but virtually no one has NOAA "SAME" radios to hear the alert. Most people don't watch TV or listen to a radio at 3AM. Most cell phones are turned off at night. The tools *are* available but we need to develop new tools to instantly communicate with people. As a storm chaser, I will tell you nothing is more terrifying than a night time tornado in or near heavy rain. It is seen only when there is lightning and is not heard due to rain, thunder and wind. It is literal Hell on Earth. Instead of bashing NOAA/NWS and cutting budgets, let's move toward ways of enabling NWS and local Emergency Service personnel to communicate with those in harm's way...even at 3AM.

Written from the scene on Saturday, February 3, 2007:

I thought I would give a little update on yesterdays Tornado. It's the second most destructive tornado to ever hit the state. Here in the villages the tally is 1000 homes destroyed or damaged and of that figure 100 destroyed. Also some public buildings destroyed and untold amount of large oaks down. At the end of our street we have a cast iron post about ten feet high with the street names on it .It was snapped off about a foot above the ground. Other sign posts were just blown over. On Buena Vista boulevard the street lights are on the center strip of the road about 30 feet high. These lights are on reinforced concrete poles. Some were snapped off a couple of feet above the ground and the reinforced steel was snapped as if cut. I measured the width of the destruction area with my car odometer and it was just about 1500 hundred feet .

The storm traveled about 70 miles on the ground till it hit the Atlantic

I took a ride down US 441- 27 through Lady Lake and it looked like somebody just took a huge hand and flattened everything. Huge Oaks Looked like someone took a giant scythe and mowed them down and deposited them everywhere. It's hard to believe only 19 people got killed as some homes were so destroyed.

I just heard on the news while typing this that the tally at the moment everywhere is 1500 structures severely damaged or destroyed so I will assume that there must at least that many more damaged if not more.

On the lighter side the news paper here ran many stories about the storm.

The next morning at first light an owner who's house had some damage looked out of his kitchen window and saw his car sticking through the garage door of his neighbor across the street. The wind blew his car right out of his own garage.

One more thing to add. I cannot believe how fast help got here . Yesterday morning they had the main roads all reopened and all the debris by the side of the roads. Last night they shut off all electric power to the affected areas so they could start assessing which houses are to be razed and which are to be repaired. This is supposed to be done by this evening. No one is to enter these areas including the owners unless accompanied by a deputy sheriff only to retrieve essentials such as meds or the like. That means about 2000 people displaced.

They opened up four shelters for people who had no where to go. Only 17 people showed up . Relatives and friends are putting them up. I got a call from a friend who offered to put us up but we didn't need it and we also extended the same offer to another couple who we thought would lose there power. Everyone is helping everyone.

This morning we went out to breakfast and to check out Lady Lake which I mentioned above. Already there were hundreds of trucks and workers ready to start rebuilding. On the way back roofs and smaller jobs were already being taken care of. Unbelievable. Certainly not like New Orleans. The disaster relief is very good and we are very impressed.

I guess that will do it for now. We will be taking pictures but no one is allowed into the neighborhoods. Just the main roads. Every side street has police car at the entrance.

NAM Takes "Game 2",
Bitter Cold On The Way,
Deadly Florida Tornado Report...And...
Phil...You're Kidding Me, Right???
Friday, February 2

Yesterday's recap: NAM model, clearly the outlier, was pretty good with Game 2 last night and this morning. Yesterday it correctly pegged where the coastal Low would be this morning, brought the lobe of precipitation from OH/TN/WVA in on schedule and had a good handle on lack of precip overnight for the interior Mid-Atlantic. Wow! Not perfect (terrible several days ago) but very impressive. I am eager to see how the NAM handles the Polar Vortex and placement of cold air upcoming next week. While not a model-hugger, I will keep a closer than usual eye on the NAM as I like riding winning horses!

Coming Cold: First Cold Front crossing the region is a mere appetizer as the Mother lode comes in this weekend when the Polar Vortex moves closer to the US. The arctic front will be from Lake Huron to Oklahoma on Saturday, On Sunday, the boundary will cross the Appalachians and drape west across the Tennessee Valley over to the Central Plains. Everyone behind the front will chill to high temperatures AT LEAST 20 degrees below normal. Bone chilling High Pressure will dominate the region well into the work week so the area remains cold and dry...however...there are a couple opportunities for winter weather next week. First is a "Clipper" late Monday or Tuesday; not sure how much moisture this will transport over to WV/VA and PA but will watch and report here. Later next week there could be mischief coming up from the south but nothing firm this far out. Critical feature over the next seven days will be importance of dressing in layers and protection from hypothermia.

Florida Tornado Report: There are 19 fatalities confirmed from a narrow band of storms that produced tornadoes in central Florida. Worst of it was near Lady Lake and Paisley Lake, FL which is about one hour northwest of Orlando. We received this morning the following email from near Lady Lake:

"We just would like to tell all of our friends and relatives that the tornado missed us by a 1/4 mile so we were very lucky. Contienuous (sic) lightning and thunder woke us up and about 3.10Am we heard our grill take off and the screaming winds and heavy rain. After a couple of minutes it abated . We found our barbecue in a neighbors yard and that is the only damage we had. The damage started nearby and damaged or destroyed 300-500 homes here before hitting Lady Lake. It's hard to get around as most streets are blocked off by police to keep out gawkers. Outside of that everything is fine and we have all of our utilities."

Thanks to Michele for sending this on the scene report. One of the mysteries of tornadoes is how someone can lose a grill and have utilities while a neighbor's home is destroyed. Storm reports HERE. You may recall a strong F-2 TOR last Christmas in Florida...very close to today's deadly tornadic storms.

Phil Sez What? We'll close on a happier note. Today is Groundhog Day and Punxsutawney Phil did not see his shadow so Spring comes early this year! Hmmm...this morning's forecast for Punxsutawney, PA called for snow and Phil must know something we do not. If Phil stays out to prepare for Spring he'll wonder why it's so cold as after today he won't see the temp hit 20° for one week...at least! Click HERE for Phil's Forecast for the next week.

Almost forgot...Proud Papa Comment: This blog is routinely read throughout the US as well as many other countries, but, a comment just for the folks around the Shenandoah Valley and Lexington, VA area. If you receive the Lexington News-Gazette you'll see see a picture of two kids wrestling in a recent tournament...big picture...right across the top of the Sports section! The boy winning the match is my 14 year old son. Somebody needs to let Joe Bastardi know there's an up-and-coming weather enthusiast who knows how to wrestle!

Thurs-Friday Storm Update #3.
Thursday, February 1

As quipped in the new RSS newsfeed, even last night the models have failed to agree on a solution and that continues even now with the event underway! First wave of precip has been weak and suppressed to the south with less snow across the Virginias and Delmarva than depicted by the Rapid Update Cycle (RUC) model. The 6Z NAM steadfastly keeps precip south of VA and it prints out less precip than current RADAR so at the moment both are busting. 12Z GFS is starting to come in now so I can't comment past noting it is still jumpy and cold. It's not unusual for the NAM and the GFS to be at odds...but 6 hours before a storm? This is crazy! Depending upon what model a forecaster or Meteorologist uses, some folks are going to bust badly with this system.

Current winter mode Radar loop (click image for more Radar):

This morning's Short Range Ensemble Forecast (SREF) keeps with the idea the first wave coming through this morning stays south with a little snow north of the NC/VA border and rain/mix for eastern NC and VA. Ice and poor driving conditions are the issue for northern GA into much of North Carolina. Light snow accumulations western NC and SW Virginia...some mixing reported for the Metros in NC. So far, so good. Staying with the SREF, second batch of precip begins later today as Low Pressure organizes just the Virginia Capes, with a mix of wet snow, sleet and some freezing rain east of the Blue Ridge and snow to freezing rain to the west. A literal degree or two difference in temperature in the low levels is what is causing this challenging forecast. For example, in Washington DC models still vary from nothing and a little rain./freezing drizzle up to 2-3 inches of snow! So, at the moment, it looks like the NAM may have the right idea for the first slug of precipitation (fast and staying south) but I don't think it is correct in showing negligible snow and rain tonight for locations north of the NC/VA border. I'll go with an average of 2" along and west of the Blue Ridge and NC mountains, generally along the Shenandoah, Roanoke and perhaps New River Valleys, then freezing rain (maybe sleet?). Elsewhere away from the coast an inch or two probable, then freezing rain. Coastal south of Delmarva...mostly rain...hard to say now as we're still uncertain where and how much warm air is transported inland.

Think the NAM is right with regard to off-shore track...coastal Low scoots away from land and this will tamp down Big Dog snow totals for the Northeast. Snow still in the forecast later Friday/early Saturday but the Low will not hug the coast ala a Nor'easter. In fact, I think the NAM could verify as predicting best the outcome of this event.

TOOLS:
I've switched our Mid-Atlantic temperature MesoMap to update at 15 minute intervals to keep you current of surface temps. Click HERE. Current advisory information at our Winter StormCenter. As temps begin to warm, wet bulb is important and you can get the wet/dry bulb temps from our wx station (approx 1,100') in Lexington, VA by clicking HERE. Current conditions and Virginia Interstate web cam links HERE.

I'll update the Blog around 5PM this afternoon...and "quickies" will go to our RSS newsfeed (info and how to fetch by clicking the RSS button to the left).

UPDATE, 5:00PM: Well, this storm goes in the books as the biggest bust since February, 2005 (affectionately now known as the Pamela Anderson Storm...if you catch my drift). What's interesting is today's flop may have been caused by that storm nearly two years ago. That storm was made into a monster by the "Eta" model (now called NAM). NWS offices clung to the Eta despite most other models pooh-poohing that storm; my local forecast was 10 to 12 inches (I forecast 6-8 inches). We received 2.5 inches and it was done. Everyone who clung to the Eta was scorched back in February, 2005, swearing to never again go with it when it is was the outlier model. Well, the NAM was the consistent outlier with this storm (so far) and I can't find a forecaster or Meteorologist who went with it...so every forecast for today was wrong. While I saw this on Monday, I didn't hint at its viability until yesterday because I don't trust the NAM and synoptically it didn't make sense to me. So, a tip of the cap to the NAM for nailing Game 1 of the 2 game set...and I can't wait to see the GFS bashing on the weather boards!!!

Game 2 is tonight when Low Pressure loosely organizes off of Wilmington and heads Northeast (but it will not become a Nor'easter and will be well off-shore). The NAM still keeps the bulk of precipitation from south Georgia into SC, central/eastern NC and SW VA. The GFS model is now mostly on board, but with a little more precip into west-central VA. The quickie RUC has the coastal Low a bit closer (west) but limited precipitation inland. Meanwhile, the 18Z MM5 puts down more freezing rain for NW NC and west of the Blue Ridge. While it may be foolish to go against the NAM in Game 2, I do think it is missing light freezing rain and perhaps a little snow (1" or less) along the Blue Ridge over to the Alleghany foothills, and so I'm with the MM5 in those areas. Freezing rain continues to threaten NC locations west of Statesville. As noted previously, I'm doubtful there will be many snow reports exceeding two or three inches south of the Mason-Dixon Line. Sure glad I wasn't one of the "6 to 8 inch snow mongers". Sheesh!

Snow overspreads PA, most of NY and gets into New England on Friday but totals are not in the Big Dog category. PA mountains could get 2-3 inches while Upstate NY and most locations in New England will top out at 2 inches or so...chump change for hearty New Englanders! As always, check your local forecast here at Mid-Atlantic WX.com.

By far, the coldest air of the season is in the wings and will be here next week. More on that later but highs and lows will easily be 20 degrees BELOW NORMAL!

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