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Posted at 7:00 AM ET, 01/12/2008

Best Snow Chance Since Early December

By Jason Samenow

But still not great; Uncertainty higher than normal

Next Chance of Accumulating Snow: Sunday-Monday
Probability: 55%
Potential Impact:

Commentary: A storm will organize off the coast of the Carolinas Sunday morning and then intensify as it merges with another storm to the northwest off the coast of the Delmarva peninsula Sunday night.

For the last several days, we've been challenged to determine whether the storm will:

(1) Stay too far off the coast to affect the metro area.
(2) Move so far inland that it will draw mild ocean air into the region, resulting in mainly a rain storm except for the mountains
(3) Take a snow lover's track far enough offshore so that the cold air holds and close enough to the coast that its precipitation reaches the metro area.

An important consideration with this storm is that very little cold air will be in place over the metro area when it begins. So precipitation is likely to start as rain (assuming the storm doesn't stay too far out to sea). Then, if the storm can develop quickly, drawing moisture off the ocean and down cold air from the north (and this won't happen if the storm moves inland), precipitation could change to snow and become moderate to heavy for a time Sunday night.

In other words, a lot of factors need to come together for accumulating snow in the metro area from this storm. As usual, areas in the north and west suburbs have the greatest chance of getting snow for the simple reason cold air is in greater supply there. However, if the storm takes more of an offshore track, areas to the west would get less precipitation due to their distance from the storm.

My current best guess is this storm will produce a period of snow Sunday night (after starting as rain) with a sloppy inch of accumulation in the immediate metro area and up to 2-4" in the north and west suburbs by Monday morning. But confidence in this first guess is pretty low. Keep checking back for any "alerts" for this evolving situation.

By Jason Samenow  | January 12, 2008; 7:00 AM ET
Categories:  Winter Storms  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   StumbleUpon   Technorati   Google Buzz   Previous: Forecast: From Sunny to Stormy
Next: Alert: On the Edge of Sunday Night Storm


Lowwwwwwwww confidence = saaaaaaaaad Mot :(

Posted by: Mot | January 12, 2008 7:04 AM | Report abuse

Nice Jason, as always. With the uncertain track, which model runs do you think will give a clearer pic 12z? 18z? 00z? or will it come down to nowcasting the movement on sunday? BTWN the difference in models, temp profiles etc, you guys got a tough 24 hrs ahead, some storm to be the 1st at the new site huh? ;)

Posted by: Mike from the Blue Ridge | January 12, 2008 7:05 AM | Report abuse

Oh overnight AFD from LWX that I can find, not on the IWIN or site.

Posted by: Mike from the Blue Ridge | January 12, 2008 7:07 AM | Report abuse

Good Luck to all the snowlovers, but I have been pessimistic about this system for the past two days and remain that way. The 06z NAM has shifted east with the qpf,the GFS remains east with sig. qp., but the greatest negative is the fact that there is simply not enough cold air around to support substantial snow for D.C. unless something changes in the next 24 hrs. I'm in Josh's court for this one regarding the D.C. potential. Any significant snow from this event is likely to be northeast of D.C.

The potential later next week may be a different ballgame!

Posted by: Augusta Jim | January 12, 2008 7:14 AM | Report abuse

Another disappointment... I hate it when NY and Philly get snow and we don't.

Posted by: Period | January 12, 2008 8:23 AM | Report abuse

Looks like a bit of rain and that's it to me...

Posted by: steve takoma park md | January 12, 2008 8:45 AM | Report abuse

I'm sure there will be nowcasting to do on Sunday. If you remember the rain storm that occurred the day after Christmas, it was forecast to be east of DC but the heavy rain pushed well west of DC. It was too warm for snow, but had it been a bit colder, that would have been a memorable forecast bust.

Posted by: Kevin, Capital Weather Gang | January 12, 2008 9:26 AM | Report abuse

Love the new snowlover's ball. Great stuff!

Posted by: Rex | January 12, 2008 9:29 AM | Report abuse

What time are we thinking for the onset? It's probably there, but I'm lazy...

Posted by: Kalorama Park | January 12, 2008 9:37 AM | Report abuse

Remains a very frustrating storm to forecast as our models keep providing different solutions. The differences are small but have important implications for the forecast.

Too much has to come together perfectly to get excited about the snowfall potential with this storm. While a little sloppy snow is possible towards the end of the storm, I think this will be a low impact event.

Posted by: Jason, Capital Weather Gang | January 12, 2008 9:43 AM | Report abuse

YAY! The SLCB is back!

Even if it is pretty much just a tease.

Might have to put the PJ's (T-shirt and sweats) on inside out and backwards tonight. LOL.

Posted by: Kim in Manassas | January 12, 2008 9:43 AM | Report abuse

Some light rain is possible Sunday afternoon and evening. The period to watch for snow would be 10pm - 1am Sunday night/Monday morning.

Posted by: Jason, Capital Weather Gang | January 12, 2008 9:47 AM | Report abuse

Lots of activity at the bird feeders this morning. Haven't seen this many birds feeding in a while...
A possible sign of snow to come???

Posted by: Havoc | January 12, 2008 10:09 AM | Report abuse

Havoc, where are you? I haven't seen much action at my feeder.

Posted by: Kalorama Park | January 12, 2008 10:28 AM | Report abuse

go to accu weather meteo madness. we are on the boderline of 3-6 in and 1-3 in.

Posted by: Anonymous | January 12, 2008 10:38 AM | Report abuse

This latest GFS run seems to wrap the low up S of New England and hammer them with hours and hours of heavy snow. Doesn't it appear that we are borderline snow/rain?

How are people able to get specific model-based forecasts off these models?

Posted by: GFP | January 12, 2008 11:02 AM | Report abuse

Anyone know of a good tutorial explaing the different weather models and how to read them?


Posted by: Snowlover | January 12, 2008 11:41 AM | Report abuse

I really don't see where it's possible to get even an inch. It's going to be waaaay to warm. This sucks as usual.

Posted by: TJ | January 12, 2008 11:49 AM | Report abuse

Anyone know of a good tutorial explaing the different weather models and how to read them?


Posted by: Snowlover | January 12, 2008 11:41 AM

Hey... One of CapitalWeather's affiliates has a thread with it. Enjoy!

Posted by: Chase, Luray (THE Valley King) | January 12, 2008 2:45 PM | Report abuse

The comments to this entry are closed.

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