Friday, December 28, 2007

First Guess on Dec 30-31 Nor'easter; Final Tomorrow PM

Here it is. My first guess for the upcoming Nor'easter that will help Boston smash its December snowfall record from 37 years. Talk about last minute. All the newest data came in around 6PM tonight and confirmed my thoughts that this will be a mainly snow event for much of southern New England, except the immediate South Coast of CT, RI and of course the Cape and Islands, where some mixing is always possible. I know it is a little early in time for putting out a map for this system, but I had to do it to give some reference point for what this storm could potentially do come Sunday night and into Monday morning. I don't think that this will be a blockbuster by any means, reason being is that the speed of this storm system will be like a rocket. It will shoot up the entire east coast in less than 24 hours. I don't think anyone will see more than 8-12 hours of accumulating snow from this storm system. However, the 8-12 hours that it does snow, it will be falling at the rates of 1-2"/hr. So, if you do the math, 6-12" for much of SNE looks like a good bet with this storm system. If it were to slow a bit as the EURO and UKMET are advertising, and we were to get extended accumulating snow than what the GFS is currently showing, some places will see some hefty snowfall totals from this one. A slower storm would give more time for the storm to gain some strength as well and that would means stronger winds and coupled with the fact that most of this storm will be in the 29-33 degree range, very marginal, the wet snow could cause power outages alone, but with wind, all bets are off. It could be a cold Monday morning in many peoples homes. So, as you can see there are still many many variables to be worked out for this storm system. I don't think areas from Boston points south and east are totally out of the woods regarding precipitation types, but I am pretty confident everyone away from the Canal will stay all snow with this event.

Next things we want to peg down with this storm will be...

1) Timing...when is this going to start. Right now it looks like Sunday night around midnight.

2) Duration....As I said before, looks like an 8-12 hour bout of heavy accumulating snows, longer duration would make all the difference.

3) QPF...how much 'water' is going to fall from the sky.

4) Snow Ratios...right now I would say right around a 10:1 ratio, which is not a fluffy snow, but not glopping wet which would be 5:1 ratio.

5) Winds...strong winds coupled with heavy wet snow would result in power outages and some minor splashover.

6) Exact Track of LP...will as always make all the difference on who sees what type of precipitation. Looking right now like an all snow event away from South Coast and Cape.

7) Speed of LP...will determine the starting time and duration.

8) Monitor your Thermometer at Home...a temperature of 31 will make a world of difference compared to temperatures around 33-34 degrees for accumulations.

I will be back on tomorrow for any watches that will likely be issued by the NWS. Go out and buy some bread and milk. Oh yeah, don't forget to stock on the nachos for the big game tomorrow thats on every channel. Lay off the beandip though...just kidding. Anyway, bring an umbrella out with you tonight if your going to be out on the town past midnight. Rain is moving in.

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