Winter's Finale: March 20th-21st Snowstorm

Check out what happens though. As the 500mb low begins to pull away from the coast 850mb temps crash and all turn to snow

WOW CCB OVER THE AREA HOURS 54 to GOD KNOWS WHEN

The issue of sleet/freezing rain is something I raised last night. The NAM yesterday evening was definitely projecting a prolonged period of sleet and/or frz rain with this. As I pointed out the 850 level temps were above freezing even as the lower level temps were are or below freezing. So there will be a period (or periods during this) where I do think many will hear that little pitter-patter of sleet on their windows.

Watches will fly up this afternoon

I'm actually liking the look of the transition to snow though because it seems to indicate snow may continue at a good intensity well into Wednesday evening -- and there will be no sun issues to deal with for that snow in terms of accumulation.

HI RES JUST DROPS THE HAMMER!!!!!!!!

amugs wrote:HI RES JUST DROPS THE HAMMER!!!!!!!!

And at 7 pm Wednesday that should be all snow for most people on here.

FWIW. I don't know how well the 12km NAM distinguishes between sleet, snow and freezing rain.

It stalls this off of ACY and just pummels the area in a CCB!!

CPcantmeasuresnow wrote:FWIW. I don't know how well the 12km NAM distinguishes between sleet, snow and freezing rain.

TT doesn't do so - need Wxbell maps for such.

Keep jogging NW- and why - stronger phase, better dynamics of bombogenesis and less confluence to the N.

For those worrying the snow won't stick due to daylight, I can assure you if you are under that heavy CCB band at 8 or 9 p.m. Wednesday evening -- sun will not be a factor.

Y understanding is that if wage 1 is too strong or amped then wave two will not come as far north. Is this not correct.?

billg315 wrote:For those worrying the snow won't stick due to daylight, I can assure you if you are under that heavy CCB band at 8 or  9 p.m. Wednesday evening -- sun will not be a factor.

The other thing to note there Bill, is that the last few storms where people were having problems accumulating during the day temperatures in most of those areas were above freezing while it was snowing 33, 34 even some places 35°. If temperatures are in the 28 to 30° range during the day time the snow is not going to have a big problem accumulating even this time of year. On some of the modeling it looks like temperatures will be in the upper 20s in many places during this period, it's just another thing to watch.

Of course I remember the April 1982 blizzard very well and a lot of that fell during the day time but the temperatures were in the mid-20s to high 20s so there was no compressing the melting even when intensity lightened up. That's 5° difference makes a world of difference during the day time this time of year.

syosnow94 wrote: Y understanding is that if wage 1 is too strong or amped then wave two will not come as far north.  Is this not correct.?

Yes. The weaker wave 1 the better wave 2 - hence hi-res NAM solution

3K

Frank_Wx wrote:

syosnow94 wrote: Y understanding is that if wage 1 is too strong or amped then wave two will not come as far north.  Is this not correct.?

Yes. The weaker wave 1 the better wave 2 - hence hi-res NAM solution

Is it possible the regular NAM is just confused and shows Tuesday's wave 1 as just the beginning of one long storm?

I'll say this...anything that falls Tuesday (wave 1) would really help accumulations for Wednesday's storm. If a layer of snow or sleet accumulates Tuesday then accumulations associated with Wednesday's snow, even during the day, should pile up. So we actually want some accumulation on Tuesday

12z RGEM looks like a hit

I'm trying to understand. This storm is coming in two seperate waves 1&2. Is there much time in between them or is it basically 1 storm with two different types of precipitation?

Taffy wrote:I'm trying to understand. This storm is coming in two seperate waves 1&2. Is there much time in between them or is it basically 1 storm with two different types of precipitation?

I think we should call it 1 storm.

Precip will start tomorrow afternoon, especially if you are from central NJ on south, in the form of snow, sleet, and rain. Mostly snow/sleet. Then there will be a lull overnight Tuesday (but some models have snow/sleet throughout the night and creeping north into NYC Metro). At 8am is when precip turns on again for the coast, including NYC, then spreads N&W through the morning on Wednesday. It will snow all day Wednesday into the night. In fact, it may not stop until 4-5am Thursday.

Winds will be a concern for coast

Frank, any mixing issues as of now for the coast here?

Smittyaj623 wrote:Frank, any mixing issues as of now for the coast here?

Probably