Historic Snow or Bust?

We are now 12 hours away from precipitation falling here in Albany, New York.  But what does mother nature have in store for us?

Well usually at this point, forecast models are usually in pretty good agreement.  This however is not the case.  Thus far the end results of these difference don’t seem to be big, but I think there will be a few surprises with tomorrows storm.

First off lets look at the NGM forecast model.  It’s old and many forecasters ignore it completely.  However I think the NGM can give us some clues as to what may happen.  At 42 hours (roughly 1pm on Monday) the NGM has a 984 mb low near Cape May, NJ.   The mid-levels warm above freezing in Albany by this point, leading to rain.  However, the NGM does forecast the mid-levels to stay below freezing through the next 36 hours.  The NGM mos numbers are a tad warm at the surface, leading to a rain/snow/sleet mix for much of the day Sunday, with little accumulation.  After 7pm on Sunday the model forecasts the mid levels to warm and surface temps to climb a few more degrees into the low 40’s making meaning plain old rain, perhaps still mixed with sleet.  As a result the NGM model generates little snow accumulation, generally under 3″ in Albany.  Surface temps on the NGM seem too high.  It’s already 37 here in Albany and dewpoints are current running a couple of degrees lower than the model has forecasted.  Web-bulb temps are now at or below freezing.  A sign for a colder solution?

The ETA model is telling a different story.  The 18z model was much further SE, but the newest 0 z model brings the system further north and west.  At 42 hours the ETA model has a 988 mb low on the NY/CT border (compared to Cape May, NJ on the NGM).  The ETA also seems warmer at the mid-levels than the NGM (perhaps due to the further north track), keeping the mid-levels below freezing for about the next 18 hours, then around freezing up to 30 hours when the mid-levels go above freezing.  By 48 hours the mid-levels have cooled again, so snow should become the main precip type. While the ETA spins the storm on the NY/CT border.  This track is closer to previous runs of the GFS model.  One other issue to keep in mind is that the ETA also seems to be having trouble deciding on a low center.  The graphics continue to depict 2 – 4 low centers all over the mid-Atlantic.  Which one become dominate will have a big impact on the weather here in Albany.  The ETA mos numbers a about 5 degrees cooler at the surface and about 5 degrees warmer in the mid-levels than the NGM model.  The result, still little snow accumulation but a much higher likely-hood of a heavy mix developing.

The GFS model through the first 12 hours has little to argue about with in terms of storm location (all 3 models have it in West/Central North Carolina).  The GFS at the mid-levels is colder than the ETA, similar to the NGM and seems to fit the current situation.  Through 24 hours storm location is similar, but the GFS is slightly colder at the mid-levels than the ETA still, but not as cold at the NGM.  However the GFS generates nearly 1.5″ of liquid… The ETA about the same and NGM about half of that. At 30 hours the ETA and GFS look similar, but the GFS is still just a hair cooler at the mid-levels which could have a big impact on the weather at the surface.  At 42 hours the GFS is similar in location to the ETA, but is much colder at the 850 mb level.  The GFS also has the strongest system with a 976 mb low at it’s peak near the NY/CT border.   Nearly 3″ of liquid is forecasted with by the GFS model.  As for snowfall accumulations, the GFS model spits out 6+” of snow in Albany with about a 9 hour stretch of snow Sunday afternoon/evening.  I still think it will be tough to get that much given the time of day and the likely hood of any snow mixing with rain and sleet.  But interesting none the less.  The GFS remains the most robust in producing snow in Albany.

The high resolution WRF model (which is ETA based) shadows the Albany area.  Only about .50 to .75 liquid precip actually falls and most of that as Rain/sleet.  It not only spares us a major snowfall, but also major flooding issues as well.  Currently this model is an outlier, but something to keep in mind, should strong, sustained east winds develop.

With all that’s been said what’s my forecast for Albany?  I expect Snow or a mix of Snow/Sleet and Rain to develop shortly before daybreak on Sunday.  It should turn to all snow shortly after starting and continue at least through mid morning.  up to 2″ of Snow/Sleet is possible, although more is possible if heavier precip moves in faster than currently forecasted.  Between 9 am and 3 pm expect the Snow to mix with Sleet and Rain and eventually turn to most rain.  With heavier precip, expect it to at least mix with sleet and possibly some snow or even change over to snow briefly.  Between 3 pm and 10 pm expect more snow/sleet to mix with the rain.  After 10 pm I expect it to change over to light rain, mixed with sleet at times.  Precip should be lighter by then.

Currently temps continue to fall in Albany due to some thin spots in the clouds.  This will help to generate snow and sleet on the front end of the storm, but overall will have little impact on the brunt of the storm.

Total snowfall accumulations 2-4″, mainly on the front end of the storm (Sunday AM).  After that, heavy mixed precip with up to 3″ of rain possible, leading to widespread flooding, even of the Hudson River.

I’ll have more updates on Sunday as the storm evolves and we will see how close my forecast comes to fruition.  At 12:15 am Binghamton, NY was reporting Light Snow and a temp of 37, while Elmira was reporting Light Rain and 40 at the same time (Same elevation too!)  Buffalo was reporting Light Snow.  The Temp in Albany is 35 and a dewpoint of 28 (web bulb around 32), precip should start in about 4-6 hours in Albany.

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