March 2-3, 2006 Snowstorm: Initial Estimates

[donsutherland1]

Southern and central New England appears to be in line for at least a moderate snowstorm. This should help Boston get off to a good start on the 10" or more figure I expect for the month overall.

Currently, there's a war between the very warm NAM, which blasts warm air though the mid-levels well north to such cities as Worcester and Boston, and the colder GFS, which keeps Boston, Worcester, and Providence in all snow. I'm leaning heavily toward the colder GFS.

1) The presence of a block (NAO ~ -1.000) makes it unlikely that the NAM's scenario of blasting very warm air--almost unimpeded--into central New England at the mid-levels is more feasible than the GFS's colder idea.

2) The 2/28 12z GFS's soundings are closest to the 2/28 0z ECMWF at 850 mb. Select examples follow (°C):

Code: Select all

City   EC   .GFS   .NAM
ALB   -7.8   -9.9   -1.2
BDL   -5.2   -7.7   2.8
BOS   -6.0   -8.2   -0.3
NYC   -3.0   -5.9   7.1
PVD   -3.6   -6.2   2.8


Differences: GFS vs. ECMWF:
Albany: -2.1°C
Boston: -2.2°C
Hartford: -2.5°C
New York City: -2.9°C
Providence: -2.6°C

Differences: NAM vs. ECMWF:
Albany: +6.6°C
Boston: +5.7°C
Hartford: +8.0°C
New York City: +10.1°C
Providence: +6.4°C

Initial Estimates:
Albany: 2"-5"
Boston: 3"-6"
Burlington: 2"-4"
Concord: 2"-5"
Hartford: 3"-7"
New York City: 1" or less
Newark: 1" or less
Portland: 1"-3"
Providence: 3"-6"
Worcester: 3"-7"

[donsutherland1]

Comparison of 12z ECMWF, GFS, NAM Soundings (3/2 12z):

Code: Select all

City   EC   .GFS   .NAM
ALB   -5.7   -7.0   -1.7
BDL   -4.2   -6.0   -2.2
BOS   -6.7   -6.9   -5.1
NYC   -1.3   -1.2   3.4
PVD   -5.1   -5.6   -3.2


Differences: GFS vs. ECMWF:
Albany: -1.3°C
Boston: -0.2°C
Hartford: -1.8°C
New York City: +0.1°C
Providence: -0.5°C

Differences: NAM vs. ECMWF:
Albany: +4.0°C
Boston: +1.6°C
Hartford: +2.0°C
New York City: +4.7°C
Providence: +1.9°C

Overall, the latest ECMWF data also leads me to believe that greater weight should be given to the GFS solution rather than the NAM one.

[donsutherland1]

Per the 3/1 0z run of the NAM, the snowfall estimates for most of the cities remain on track. Southern and central New England should receive a moderate snowstorm.

In my view, the NAM's track off southern New Jersey/Delaware coast and east-northeastward is reasonable. Hence, my confidence in the threat of a winter storm for central and southern New England is growing.

At the same time, there is a growing possibility that a colder solution could work out even into New York City. The 0z NAM brings a mostly or wholly snow event very close to NYC. Currently, the line is near White Plains, NY. That's a very small margin for error. Therefore, should later model runs hold up, I could well raise my snowfall estimates for NYC.

Ice could be a problem, especially in the Lehigh Valley and Poconos.

For now, I'll leave my estimates as they stand. After the additional 0z guidance and later 6z and 12z guidance, I'll offer a revised estimate.

Initial Estimates:
Albany: 2"-5"
Boston: 3"-6"
Burlington: 2"-4"
Concord: 2"-5"
Hartford: 3"-7"
New York City: 1" or less
Newark: 1" or less
Portland: 1"-3"
Providence: 3"-6"
Worcester: 3"-7"

[Windtalker1]

Per the 3/1 0z run of the NAM, the snowfall estimates for most of the cities remain on track. Southern and central New England should receive a moderate snowstorm.

In my view, the NAM's track off southern New Jersey/Delaware coast and east-northeastward is reasonable. Hence, my confidence in the threat of a winter storm for central and southern New England is growing.

At the same time, there is a growing possibility that a colder solution could work out even into New York City. The 0z NAM brings a mostly or wholly snow event very close to NYC. Currently, the line is near White Plains, NY. That's a very small margin for error. Therefore, should later model runs hold up, I could well raise my snowfall estimates for NYC.

Ice could be a problem, especially in the Lehigh Valley and Poconos.

For now, I'll leave my estimates as they stand. After the additional 0z guidance and later 6z and 12z guidance, I'll offer a revised estimate.

Initial Estimates:
Albany: 2"-5"
Boston: 3"-6"
Burlington: 2"-4"
Concord: 2"-5"
Hartford: 3"-7"
New York City: 1" or less
Newark: 1" or less
Portland: 1"-3"
Providence: 3"-6"
Worcester: 3"-7"

I agree to a good chance of moderate snowfall but I think this will turn out to be a southern New England storm mainly South of the Mass Pike. The heaviest snowfall will be Connecticut, New York, Long Island and Rhode Island with up wards of 8-12" for this area. I enjoy your post and learn a Lot from them.

[weathermom]

Don- any additional thoughts? NWS says 4-8", you gave us the dreaded 1" or less again......... I like theirs better! (though you are usually more accurate!)

The kids will be pulling for the NWS to be right, with all the rituals that are supposed to bring snow (and snow days)!

[carve]

Accuweather saying storm to move through southern ohio to the Va.coastline...............Although spring is approaching, winter doesn't want to give up its grip across the Northeast. On Monday and Tuesday, a strong storm system moved into the West Coast, bringing heavy rain and gusty winds to California. Now, this storm is currently moving across the Plains. Earlier in the week, it appeared that this storm would harmlessly track across New England, bringing more rain than wintry precipitation. However, latest computer guidance is suggesting that this storm will track through the Ohio Valley and straddle the Pennsylvania/Maryland border on Thursday before heading out to sea. In addition, this storm appears that it will strengthen and gather extra moisture from the moist Southeast. This will allow accumulating snow and ice to fall across Pennsylvania, New Jersey and all across southern New England. While this storm will be a quick hitter, it has the capability of producing 6 inches of snow in some areas, as well as a dangerous accumulation of ice. Roads all across the region will be very slick for Thursday morning's commute. Check back at Accuweather.com throughout the day for the latest on this upcoming winter storm. Story by AccuWeather.com Meteorologist any thoughts..thats a pretty good shift south.

[donsutherland1]

After reviewing the ensembles and having a look at the 12z NAM (including its soundings) and the 12z GFS, I believe the storm will likely move off the Delmarva and then head east to somewhat east-northeast. As a result, I'll have to adjust my area of heaviest snow to the south of that in my initial estimate from yesterday.

In addition, somewhat colder profiles seem likely for such cities as Allentown, Harrisburg, and Philadelphia.

All said, this storm should bring both NYC's and Boston's seasonal snowfall above 40". NYC will record its 4th consecutive season with 40" or more snowfall. This wil double the earlier record set previously in 1882-83 & 1883-84, 1895-96 & 1896-97, 1915-16 & 1916-17, and 1947-48 & 1948-49.

There remains some potential for a somewhat farther south track than I'm estimating. However, given the ensemble means and the 12z GFS, I believe that the southward shift has stopped. A slight reversal to the north is even possible.

3/2-3 Snowfall Estimates:
Albany: 1"-3"
Allentown: 2"-5"
Boston: 1"-3"
Burlington: 1"-3"
Concord: 2" or less
Harrisburg: 1"-3"
Hartford: 2"-5"
New York City: 3"-6"
Newark: 2"-5"
Philadelphia: 2" or less
Portland: 1" or less
Providence: 2"-5"
Worcester: 1"-3"

[weathermom]

Thats more like it!

[plainsman]

bla, bla, bla, northeast , northeast.... whenever theres a big snow storm in the northern plains theres not a million posts about it on here and it doesnt get national recognition from newspapers and temps are much colder in the northern plains....... i get annoyed by so many people posting things on 1-3 inches of snow.... people in Minnesota dont go crazy whenever a couple inches of snow falls......minnesota northeast

[donsutherland1]

Plainsman,

One of the things that makes the upcoming storm notable--if it verifies--is that it would bring NYC to 40" snow for the 4th consecutive season. Such snowfall is, in climatological terms, roughly the equivalent of a 70" season at Minneapolis-St. Paul. Prior to the current stretch of 40" or greater seasons, the record for consecutive seasons was 2. That historic record goes back to 1869-70.

[donsutherland1]

Per a review of the 0z NAM and quick look at the 0z GFS, I believe my general ideas are in reasonably good shape. I have tweaked a few areas, but most estimates remain unchanged.

Final Estimates:
Albany: 1"-3"
Allentown: 2"-5"
Boston: 1"-3"
Burlington: 1"-3"
Concord: 2" or less
Harrisburg: 2" or less
Hartford: 2"-5"
New York City: 3"-6"
Newark: 2"-5"
Philadelphia: 1" or less
Portland: 1" or less
Providence: 3"-6"
Worcester: 1"-3"

[Stephanie]

I'm south of Philadelphia and this morning when the rain started it did freeze. We must've been right at the freezing mark. We didn't get any snow - line was more off to the north of the Philadelphia area and just south of Trenton.

[Dave C]

Here in Middleboro MA a very heavy band is moving through. after half an inch early this afternoon we had a lull but now heavy snow is falling with very low visability. Looks like 3-6 inches is a good call here with more mod to heavy bands moving in from Conn.

[Stephanie]

Overall, it was just a rainy, raw day. We have alot of buses that come to my casino daily but there were alot of cancellations due to the snow up north.

[plainsman]

ya nyc does get the big noreasters and huge snowfall amounts (12 plus inches) in one storm that minnesota rarely gets ... minnesota is just bitterly cold and gets moderate continuous snowfalls thruout the year, not the big monster noreasters like the northeastern coast can get in nyc boston and philly...

[Stephanie]

ya nyc does get the big noreasters and huge snowfall amounts (12 plus inches) in one storm that minnesota rarely gets ... minnesota is just bitterly cold and gets moderate continuous snowfalls thruout the year, not the big monster noreasters like the northeastern coast can get in nyc boston and philly...

Those big Nor'easters are sometimes the only way we get snow in the Mid Atlantic and North East. That's probably also why we make more of a big deal of a snow than most of the other areas in the snow belt. It's more the norm for you.

[coriolis]

Hey DonSutherland, how come Williamsport isn't on your list? We had about 2-3 inches of sloppy mess here. While the roads did get a bit slippery, it was more of a nuisance to me. Nothing that the anti-lock brakes couldn't handle!

I've been tracking actual temperatures vs. climatolological averages. As much as we're all tired of winter, the temps have been comparing favorably with the averages. March can be a frustrating month around here. You want it to be warming up, but according to the averages, March is about like December.

[donsutherland1]

Verification:

For many locations, this storm proved disappointing. For me, busts abounded. After a review of some of my earlier posts and data, several factors seemed to suggest that the storm was not a lock to produce a moderate snowfall for some of the locations that changed over to sleet and freezing rain.

• Succeeding runs of the ECMWF brought its forecast 850 mb readings ever closer to those cited by the NAM on 2/28.
• On the morning the storm commenced, the actual 700 mb readings were closer to those of the NAM than the GFS.
• Later guidance with some degree of discontinuity suggested a very sharp cutoff of qpf on account of dry air to the storm's north.

From 2/28/2006 1 pm:
Albany: 2"-5"; Actual: None; Error: 2.0"
Boston: 3"-6"; Actual: None; Error: 3.0"
Burlington: 2"-4"; Actual: 0.1"; Error: 1.9"
Concord: 2"-5"; Actual: None; Error: 2.0"
Hartford: 3"-7"; Actual: 4.8"; Within range
New York City: 1" or less; Actual: 1.3"; Error: 0.3"
Newark: 1" or less; Actual: 1.2"; Error: 0.2"
Portland: 1"-3"; Actual: None; Error: 1.0"
Providence: 3"-6"; Actual: 6.2"; Error: 0.2"
Worcester: 3"-7"; Actual: Trace; Error: 3.0"


From 3/1/2006 11 am:
Albany: 1"-3"; Actual: None; Error: 1.0"
Allentown: 2"-5"; Actual: Trace; Error: 2.0"
Boston: 1"-3"; Actual: None; Error: 1.0"
Burlington: 1"-3"; Actual: 0.1"; Error: 0.9"
Concord: 2" or less; Actual: None; Within range
Harrisburg: 1"-3"; Actual: None; Error: 1.0"
Hartford: 2"-5"; Actual: 4.8"; Within range
New York City: 3"-6"; Actual: 1.3"; Error: 1.7"
Newark: 2"-5"; Actual: 1.2"; Error: 0.8"
Philadelphia: 2" or less; Actual: Trace; Within range
Portland: 1" or less; Actual: None; Within range
Providence: 2"-5"; Actual: 6.2"; Error: 1.2"
Worcester: 1"-3"; Actual: Trace; Error: 1.0"

From 3/1/2006 11 pm:
Albany: 1"-3"; Actual: None; Error: 1.0"
Allentown: 2"-5"; Actual: Trace; Error: 2.0"
Boston: 1"-3"; Actual: None; Error: 1.0"
Burlington: 1"-3"; Actual: 0.1"; Error: 0.9"
Concord: 2" or less; Actual: None; Within range
Harrisburg: 2" or less; Actual: None; Within range
Hartford: 2"-5"; Actual: 4.8"; Within range
New York City: 3"-6"; Actual: 1.3"; Error: 1.7"
Newark: 2"-5"; Actual: 1.2"; Error: 0.8"
Philadelphia: 1" or less; Actual: None; Within range
Portland: 1" or less; Actual: None; Within range
Providence: 3"-6"; Actual: 6.2"; Error: 0.2"
Worcester: 1"-3"; Actual: Trace; Error 1.0"