2/28-3/1/2005 Storm: Initial Estimates

[donsutherland1]

On February 23, in the post concerning extreme blocks, I noted: Considering that February 2005 is all but certain to see the SOI average -10.00 or below and Winter 2004-05 was a weak El Niño winter (not a La Niña one), should the NAO drop to -5.500 or below in coming days, the probability of a Kocin-Uccellini snowstorm at some point as the extreme blocking episode begins to weaken could be high.

Per that study of extreme blocks and consistent guidance from the ECMWF/ECMWF ensembles/GFS ensembles, I believed that an offshore/coastal track was more likely than something punching inland, much less west of the Appalachians. Now, as we move into the eve of the event, and the strong model consensus that has more or less held firm, I have confidence that Winter 2004-05 is going to witness its second "Kocin-Uccellini" snowstorm of the season. This will likely also be a widespread event that could register a high 3 or even low 4 on the NESIS scale.

To be sure, I had envisioned an accumulating snow-changing to rain-ending as snow scenario for the big cities but had not expected that the amounts of snow would be as substantial as now appear likely. Larry Cosgrove had seen the full snowy potential for days out end, so his medium-range outlook is noted for its excellence.

At 18z, the NAM continued its slow but steady march toward the GFS and the offshore/coastal model consensus. Earlier, I had been wary of the NAM even as I gave it far less weight than the other models on this event. With its continuing eastward trend, my concern is much reduced.

As of now, my initial estimates for total snowfall (even considering changeover issues in some of the areas) are as follows:

Armonk: 12"-18"
Babylon: 6"-12"
Baltimore: 6"-12"
Boston: 6"-12"
Morristown: 12"-20"
New York City: 8"-16"
Newark: 8"-16"
Philadelphia: 7"-14"
Poughkeepsie: 8"-14"
Providence: 6"-10"
Richmond: 2"-5"
Trenton: 8"-16"
Washington, DC: 5"-10"
White Plains: 10"-18"
Winchester: 4"-8"

[RestonVA]

any chances on those numbers for DC and the NW burbs going up? (I'm about 20 miles west of DC)

[EXTONPA]

latest GFS shifts storm track westward....looks like big cities, including Jersey will see minor to moderate snow accumulations at most, with heaviest snows in interior New England.

1-2 Baltimore
2-4 Philly
3-5 NYC

[EXTONPA]

whenever a Noreaster cuts up over buzzards bay general rule is rain in big cities and snow in interior northeast....

[ohiostorm]

How bout us here in the midwest? Got any estimates for us?

[donsutherland1]

Just a note...

The 18z GFS does not shift significantly west of its 12z run. Here's the 18z run for 3/1 0z:



The following is the 12z run for 3/1 0z.



Notice that the positions are almost identical.

[krysof]

that will likely change again by 0z which is a much more accurate model analysis

[donsutherland1]

Akron: 3"-7"
Cleveland: 4"-8"

[donsutherland1]

Krysof,

As far as I'm concerned, there was great continuity between the 12z and 18z runs of the GFS. I expect few changes at 0z. The overall ideas expressed at the beginning of this thread look to be in good shape.

If anything, the 0z NAM will probably continue its eastward shift.

[WXBUFFJIM]

Yea, nothing has changed with respect to the GFS. I see no westward shift from one run to the next. Seems like everything remains on track. If GFS solution is correct, 6-12" in Baltimore would verify and even locally heavier amounts are possible in heavier mesoscale banding features. Will see. The exact track is key.

Jim

[donsutherland1]

Absolutely right, Jim. For many, a very exciting storm is in store.

[al79philly]

Don thanks for turning me on to the NESIS scale... I had never heard of it before this. Anyone who loves the snow should read this paper - http://www.weatheranswer.com/public/NES ... s%20scale' - it is very interesting.

[Planetsnow]

Don.....can you estimate snow amounts for Rochester, NY including LES?

[JRwx]

Don, any idea on what things will look like for accumulations with the midwest low near detroit?

[donsutherland1]

Planetsnow,

3"-6" general snowfall. After that, it will depend where the bands set up. Those areas could see significantly more snow due to the LES. Unfortunately, it is not really possible to highlight in advance specific areas for such banding.

[donsutherland1]

JRwx,

2"-4" is probably a good bet for the Detroit area.

[Mike2002]

Don--do you see Richmond just getting around one inch of slush before changing over to all rain tomorrow morning??

[donsutherland1]

Mike,

I have Richmond at 2"-5". We'll see. This is tough and I may be out on a limb on that one. Time will tell.

[EXTONPA]

Good call on the snow amounts Sutherland!

[donsutherland1]

The tragedy of a massive bust: February 28-March 1, 2005 Storm:

Armonk: 12"-18"; Actual: 7.1"
Babylon: 6"-12"; Actual: 6.8" (Islip)
Baltimore: 6"-12"; Actual: 3.2"
Boston: 6"-12"; Actual: 8.1"
Morristown: 12"-20"; Actual: 9.5"
New York City: 8"-16"; Actual: 7.7"
Newark: 8"-16"; Actual: 9.4"
Philadelphia: 7"-14"; Actual: 5.6"
Poughkeepsie: 8"-14"; Actual: 6.4"
Providence: 6"-10"; Actual: 6.8"
Richmond: 2"-5"; Actual: 0.3"
Trenton: 8"-16"; Actual: 6.3"
Washington, DC: 5"-10"; Actual: 2.2"
White Plains: 10"-18"; Actual: 7.1"
Winchester: 4"-8"; Actual: 5.0"

10/15 were busts.