Friday, February 17, 2012

Can't Hardly Wait
-  title of 1998 teen comedy

5:15 AM EST 2/17/2011 On this important Happy Friday of President's Weekend, we know may readers have major plans for travel, touring or relaxation in the days ahead. Others in emergency management or facilities management are having their plans turned upside down by the potential of a holiday weekend snowstorm. For students and teachers in the Mid-Atlantic, "just getting one day off" is something or which we know you can't hardly wait. 

Our Winter Stormcast Team continues to see the potential for a significant winter storm to strike the Mid-Atlantic region late this President’s Day weekend. However, we do not believe this storm will rank alongside previous high-impact events associated with this uniquely frequent weekend of snow events from the past. Thus, "#PDIII-jr" is the new moniker assigned to this storm by our team. 

With many readers seek as much information on the storm as possible, we offer this assessment following our multi-state collaboration last night:

  • Development: Computer models are showing the two jet streams across the country combining together Saturday night to produce a deepening storm system for Sunday. 
  • Track: Low pressure is expected to track from the Southeast U.S. to the Mid Atlantic coast during the day Sunday.
  • Timing: Computer models are now delaying the precipitation onset until early to mid Sunday morning, and exiting the region Sunday night.
  • Precipitation: The storm should begin for most regions as rain from Virginia on south, with an area of snow to the north. Given that surface temperatures will be near to above freezing, rain may mix with snow for a period on Sunday, before changing to all snow. 
ACCUMULATIONS & ANALYSES We will be issuing preliminary ideas on snowfall amounts later today, with Storm Grade Amounts on Saturday for selected locations. Our Meteorologist Advisors have posted two discussions in the Winter Stormcast Zone for your review which detail a few key points from their analyses of the storm situation as of Thursday afternoon. 

(Lead Forecaster Jason M., Winter Stormcast Team; Advisors Foot, Berk Winstead)


BioPat said...

Well, my initial call was a 10" or more event between the 12th and the 21st of Feb.  So for Sunday, I'll stay with that prediction, I know there's a huge body of moisture with this storm, but a large part of it will be OTS before we see it.  There has been so much conjecture in reading the models and we're still about 48 hours out, so this will remain interesting to watch - and enjoy! 
:-D :-D :-D :-D                 

hocoKtchr said...

It seems like all the tv weather folks are now jumping on the bandwagon....which usually turns the "bandwagon" away from snow!  ;)   I'd love to have a big, or even a "bug" kahuna- just for fun!

Andy, Southern York County, PA said...

I think in terms of heavy snow prspects things look real bad for this region.  If you would be satisfied with a 2-4 inch event then we are still very much in the game.  ALL options are on the table and NO ONE KNOWS what will happen.  All we can do is use the evidence we have and put forward the most likely scenario at this range with such a dynamic system.  I think Justin Berk is very wise for not posting accumulations at this range becasue it still COULD be 12 inches or NOTHING.  I am leaning towars NOTHING to 2-4, based on recent trends.  As we have observed in the past with many a storm that is this complicated a small shift in one variable yields a huge impact on an entire forecast.  I am looking for shifts this afteroon. 

Best guess at THIS RANGE

snow showers/mix 20%
1-2 inches low impact grassy surface mix type event 35%
2-4 inches 25%
4-8 inches 15%
8 inches + 5 %

OBVIOUSLY THIS IS JUST A GUESS BASED ON MODEL OUTPUT AS OF THIS MORNING.  We will have a much better idea by tonight and even this afternoon.

JULIE said...

I dislike this post Andy (though I know you speak the truth!)

Andy, Southern York County, PA said...

I can dress it up a little if you like.

 I am nearly certain SOMEONE will see a foot of snow out of this storm and it will be a VERY HIGH impact event.

(That soemone is likely in sw VA and the mountains, but it does make the post look better :-P ) 

Andy, Southern York County, PA said...

still time for change, so it is not written in stone.

Jason Mitchell said...

Andy, are you thinking a more southerly track (limiting QPF), or a more northerly one (rain mixing with snow to limit snowfall amounts)?

Andy, Southern York County, PA said...

It will be a colder more southerly track.  Question is do we get a more north jump to get us in the better QPF.  Latest NAM shifted north which would put baltimore south into winter storm warning criteria.  We have to see what the other models do in terms of a north shift.  I think we won't know for certain until Saturday evening where we sit.