Severe Thunderstorm Watch…NC/SC

Severe Thunderstorm Watch until 9PM tonight for SE North Carolina to Savannah, GA. Biggest threat is large hail but isolated tornadoes are possible.

More at: http://www.midatlanticwx.com/watchmap.htm

Updated discussion at Scott’s blog: http://www.midatlanticwx.com/blog.htm

Does the NAM Rule Again?

11:15PM quick comment: I’ve been on the road again tonight and it seems listening to radio the stations using the NWS for forecasts are talking up the GFS because it is not what I see tonight. After a few minutes look-see at what’s currently happening and the 00Z models, I’m with the NAM.

Last 2 Mid-Atlantic ice events the NAM did better than the GFS and tonight the GFS appears too warm. Also, much of what’s now on Radar isn’t reaching the ground, but humidities are slowly climbing in repsonse to the precip. Our temp at this time in Lexington, VA is 37° but the wet bulb is 30° so I’d think precip begins as frozen and not liquid in this area.

The 3Z (10PM EST) RUC wraps the 2M freezing line around the north and western boundary of the state and prints out snow/FZRA only up I-81 north of Staunton, NOVA and MD…everything else rain. Not the same verdict as the NAM but interesting.

No changes to amounts and p-types as outlined in earlier post and this morning’s discussion at Scott’s blog. Essentially, very little FZRA south of VA I-64 (Staunton-Charlottesville-Richmond-Norfolk). I-81 corridor/Shenandoah Valley sees snow/sleet change to FZRA north of Lexington. My worry is significant icing up I-81 north of Harrisonburg as this area often holds on hard to cold air sunken in the valley and wedged along the mountains.

Hope to have a Sunday morning discussion at Scott’s blog: http://www.midatlanticwx.com/blog.htm

Have a good night.

2nd PDS Tornado Watch & 18Z NAM

3:45PM: 2nd Particularly Dangerous Situation (PDS) Tornado Watch box up covering E TX/OK over to MS & SW TN. Strong storms will continue into this evening and persons in watch areas must remain alert for rapidly changing weather. Current info: http://www.midatlanticwx.com/watchmap.htm.

18Z NAM looks colder north of the Mason-Dixon Line. I’m still thinking bulk of frozen precip stays north of VA I-64 and west of I-95 south of DC. I-81 Winchester-Lexington may get more freezing rain…however…it is possible most will fall as plain rain. No big changes to snow area from this morning’s blog discussion: several inches south of Rt. 17 southern Tier NYS into lower PA. BAL-NYC I-95 corridor could become a Black Ice Freeway Sunday afternoon into Monday commute!

Hope to update blog tonight if able to do so…if not please check here for the latest.

Scott’s Blog: http://www.midatlanticwx.com/blog.htm

00Z NAM = Winter Lover’s Heartbreak

Long day and I’ve just now looked at the 00Z runs. GFS much the same however the NAM has slightly warmed up and backed off on precip for the Mid-Atlantic.  I’ve argued with some friends that the last 2 icy events were generally nailed by the NAM so we’ll see how this goes.

GFS seems to have prolonged the wintry precp for Mid-Atlantic and especially PA into Monday. There’s some blocking downstream which is probably why the GFS is slow poking the precip. I’m not with the GFS on this but will comment on the 12Z run tomorrow

Looks good for a winter mix…perhaps snow/sleet changing  mixing to FZRA  along the Mason-Dixon Line on Sunday. Snow interior PA looks good but unsure of amounts due to not reviewing modeling data (3-5 inches?). If the NAM is right this is mostly cold rain for VA with little frozen.

Hope to have a full discussion at Scott’s blog later Saturday morning: http://www.midatlanticwx.com/blog.htm

Have a good night

Return of Ice, Ice, Baby.

Hectic road schedule today (please see yesterday’s blog at http://www.midatlanticwx.com/blog.htm). I do not have full access to data so this is brief.

Quick comments on the 12Z Friday models continue thinking enough cold air (CAD) wedged in over VA for a snow/frain/freezing rain ordeal Sunday. There are differences on the 850 line as well as the 2M temps but overall it appears a wintery event north of the VA/NC border (again). Guidleline right now may be FZRA/SN/RA in and near I-81 corridor north of Roanoke along with NOVA, Delmarva and S. PA…but my confdence is not high right now.

SEVERE: North TX into KS today…Supercells and strong Squall Line storms expected. Tomorrow: LA/AK/MS/AL…might expand into western TN Valley.

This is going to be an expansive storm producing snow and very strong winds to the north of the track. “Storm Cancel” on any severe wx for Ohio Valley and Mid-Atlantic…despite good dynamics and instability, too cold so the threat will be snow/ice and not thunderstorms.

I’m interested in seeing how strong storms get tomorrow near LA as this helps determine if moisture is “robbed” from the storm downstream (Mid-Atlantic up into lower Ohio Valley).

Attempting to have a discussion tonight on Scott’s blog but travel and personal commitments may preclude doing so. If I’m unable to blog I will have another post here on the news feed. Thanks.

Dangerous Mid-Atlantic Wind Event Through Friday AM

Strong winds to 60MPH expected for much of the region as well as interior SE US as a strong Cold Front races through underneath Clipper producing snow to the Northeast. Downed limbs and power failures (again) are possible, especially tonight…use caution driving and be prepared!

Major late winter storm a/k/a “The Big Show” begins Friday with storms and tornadoes likely from TX to KS. Threat crosses Mississippi and Tennessee Valleys on Saturday. Rain for Mid-Atlantic could include storms and a threat of wintry mix north of VA I-64.

Full discussion at Scott’s blog posted Noon Thursday: http://www.midatlanticwx.com/blog.htm

Check the strong winds in real-time at our weather station: http://www.midatlanticwx.com/wx.htm.

Widespread, Significant Severe Storm This Weekend!

A *significant* storm will develop this week near the Rockies, intensify and track east this weekend. Along and south of the storm track, severe weather including tornadoes is possible. To the north/northwest of the storm, heavy snow and strong winds could produce blizzard-like conditions as much colder air rushes in behind the storm. A discussion on this potential event is online at Scott’s blog: http://www.midatlanticwx.com/blog.htm. Timing remains uncertain but the storm should be underway near TX by Friday night.

We suggest subscribing (free) to our news feed for rapid-fire updates on this potentially significant and severe event.

Ice Invading Mid-Atlantic, Tornadoes Torment the South!

Freezing rain and drizzle with some sleet spots moving into Mid-Atlantic.  Cool air at surface being overrun with warmer air aloft and FZRA will be primary p-type overnight. Significant icing is expected in areas previuously outlined here and at Scott’s blog. Many locations reporting “black ice” north of I-64 and over the Alleghany Highlands. Little to no additional SN in areas that had accumulation south of Mason-Dixon Line.

Several Tornado Warnings in central Alabama and multiple Tornado Warnings along GA/SC border. Strong thunderstorms continue this evening as well in affected areas.

With the secondary (coastal) Low cranking up the energy hand-off from the Primary is making this a wild night. It horrifies me the NOAA “Hurricane Hunter” reconnaissance fleet is totally grounded due to no budget. Yes…if NOAA wanted to research this storm by flying in while it is off shore, they could not! What pathetic government we have.

Tues 2PM Update

Temps at or below freezing now generally north of VA I-64 w/SN from OV to PA/NJ filling in NOVA. South of I-64, rain east of blue Ridge…rain and some FZRA down Shenandoah and Roanoke Valleys.

No major changes to forecast thinking presented in previous blogs including this morning’s discussion: http://www.midatlanticwx.com/blog.htm

MM5 model now drilling coastal Low inland over Eastern Shore and Philly and this would keep precip liquid longer along the coast up to Metro NYC. Need to watch tonight.

Conditions worsen this evening with cold air at surface, warmer air just aloft. Significant icing still expected north of NC. west of I-95 corridor.

Interesting: our wx station temp is 33°F, Wet Bulb Temp is 32.3°F…getting *very* close for frozen precip at our location in Lexington, VA.

SEVERE: Severe Thunderstorm and a Tornado Watches should be monitored from MS to Miami, FL. New watch box could go up anytime for GA…very strong storms could reach SC Low Country this evening.

Update on the blog around 5PM.

Showtime, 00Z Models & Tornado Trouble

Quick comments before The Big Show (apologies to John Boy & Billy) gets underway.

00Z NAM: steady. No SN south of I-64 (if that!). IP/FZRA western VA and NOVA…rain and some IP elsewhere except southern VA: all rain. IP/FZRA eventually overtakes most of E PA, NJ and I-95 corridor as well as coastal Down East Maine. Thumpin over PA, Upstate NY and interior Northeast. Widespread 12+ inches north of PA Tpke.

00Z MM5 (yes, I like this model for near term winter in the East): close to NAM but more RA less FZRA for VA and brings 2nd batch wrap around SN to NE coast (SN to RA to SN).

00Z GFS: Goes Berserk off Long Island! Liquid totals over 2 inches for NJ, Metro DC, LI and CT nearly all of which is SN! Very deep Low Pressure right on the coast then hugging inland. If verifies…huge blizzard in this area! I don’t know how the GFS can keep I-95 all SN?!?! Monstor snow totals Poconos to Berkshires and northern New England.

03Z RUC: No measurable precip south of VA I-64 in the 12 hour run. SN from NOVA north.

*ALERT* !!! Severe threat still looms overnight for LA and MS for strong storms and tornadoes. Folks in the affected area should monitor NOAA Weather Radio overnight.