Friday, February 17, 2012

Colder and Snowier?

9:15 PM EST 2/17/12 | Several computer model outputs this afternoon have begun a much colder and more snowy solution for portions of the central and southern Mid-Atlantic Sunday night into Monday. Our team's earlier analyses of a potentially slower moving storm has played out in the current projections for this weekend. 
  • Snow arrival is expected Saturday afternoon in the Mid-Mississippi Valley Saturday afternoon, the southern Ohio Valley Saturday night, in the Blue Ridge Mountains by Sunday morning, and I-95 corridor of Washington to Baltimore, by Sunday evening. 
  • Significant accumulations, generally defined as 4 or more inches in 12 hours, remain possible the areas noted in bright white on the snowfall timing map. This evening our Winter Stormcast Team will begin developing snow amounts for issuance on Saturday.
  • Continue monitoring the National Weather Service for watches which may be issued this evening. Our team is holding a collaboration at 10:00 PM with an update to follow.
Thanks to Forecaster Jason Warren of the Northeast Ohio Zone for producing our snowfall timing maps.


ravensbbr said...

This storm = week in the stock market . Up, down, up, down...

Andy, Southern York County, PA said...

Short term /Saturday night through Sunday night/
..the models came in slower and colder with the storm that will
impact the area Sunday. The surface low tracks from South Carolina
Sunday afternoon to just off of Cape Hatteras Sunday evening. A cold
front drops down from the north and will be almost right over the District of Columbia
area Sunday afternoon. The GFS and NAM have more cold air aloft than
their previous runs. Precipitation works from south to north across
Virginia and Maryland during the day on Sunday. Closest to the
surface low a period of mixed rain and snow is possible. Farther
north it is likely to be all snow but there will be less
precipitation. The highest confidence that snowfall exceeding 5
inches will be along the northern Virginia Piedmont area to the
Shenandoah Valley. Winter storm watches will be issued for these
areas from early Sunday morning through early Monday morning.

Snowfall amount confidence is lower for the Washington District of Columbia and
Baltimore areas. Guidance shows there is a good chance for snow to
accumulate on area roadways Sunday...but it is uncertain how much
will fall. There will be a real tight precipitation gradient north
of the front. We have raised precipitation chances to categorical
for the metropolitan areas and indicated precipitation will be all snow.
We will continue to monitor this as the track of the surface low
becomes more clear. Precipitation may start out as a mix of rain
and snow in southern Maryland. Snow will taper off to scattered
snow showers Sunday evening and precipitation will end Sunday
night. Icy roads will likely impact the region into early Monday

Andy, Southern York County, PA said...

I agree, but it is WAY MORE DOWN.  One step down, half step up, another 2 down again, half step up,...  I still think the writing is on the wall that 1-3 may fall in Baltimore, but snowfall rates will be low and it will not stick.  In the end it will be a more wet ground than white.  I don't think this will be a plowable or shovelable snow in terms of concrete.  I hope there is some MAJOR MAJOR change tonight becasue I would LOVE some major snow, but having followed these systems for over 10 years, and knowing the airmass that preceeds this storm, I understand that it will look more like a mid March event that never sticks, than a Feb storm.  I have faith in the flakes falling, but no amounting to anything.  This will like like a snow shower event and not a storm.

ravensbbr said...

check out this feed, looks like maybe the low splits around Sat night? Chance of rephasing? Newfoundland high strong enough to block? Wistful thinking? :-D

ravensbbr said...

You're probably right, but I'm still hopeful. Just as well, I have a scrimmage Sunday afternoon if the weather holds, so either way is cool. Although playing football in the snow is a blast... 

hocoKtchr said...

<pre>"Icy roads will likely impact the region into early Monday

This part I like!!! ;) 2 hours late would be ideal!!!!</pre>

Andy, Southern York County, PA said...

<span><span>I doubt Baltimore will even see any snow showers at this point.  The one model that was favorable just took a significant jump south (the NAM).  At this rate anyone north of DC including DC will be lucky to see a snow shower.  When your most aggressive pro snow model says no, agreeing with the globals at this range.  We can close the books on this one.   
</span></span> :'( <span><span> </span></span>
On the bright side it has been fun tracking, and that is a major victory for a bad winter like this.  If anything we had something to chase, and it was OHHHH SOOOOOO CLOSE </span></span> :)