February 2011 Thoughts: Another 'Atypical' La Niña Month

[uncle W]

Following up on the theme of a snowy to very snowy winter for Boston and New York City, here's the data for moderate/strong La Niña cases prior to 1940. There were twelve such cases with a winter ENSO Region 3.4 anomaly of -0.75 or lower in the 1871-72 through 1939-40 timeframe. The following are the seasonal snowfall statistics for those two cities:

Boston:

Mean seasonal snowfall: 56.6"

Least: 10.0", 1875-76

Most: 96.4", 1873-74

< 40": 25% cases

50" or more: 67% cases

60" or more: 50% cases

70" or more: 25% cases

New York City:

Mean seasonal snowfall: 36.9"

Least: 18.3", 1875-76

Most: 60.3", 1872-73

< 20": 8% cases

30" or more: 67% cases

40" or more: 33% cases

50" or more: 25% cases

Some big snowstorms happened during those years...

18.0" 12/26/1872...one more 6" storm and many smaller ones...

11.0" 2/3-4/1876...one good storm...

7.5" 2/25/1874...four storms 6" or more...

[A-L-E-X]

1875-76 must've been a weird winter. NYC had 11 inches of snow in one storm yet Boston had only 10 inches for the whole season.

[donsutherland1]

Don, how's it looking for Ottawa on Wednesday? Bust?

Just a few cm. of snow and probably not directly related to the storm on or just off the East Coast.

[FrederickWX]

As someone who enjoys and looks forward to the warmth of Spring, I'm fearing that Spring is going to be very much delayed this year, and that March will continue the bitter cold for the east. The ponds around here have been frozen since around Thanksgiving (with no thaw at any time during the period), which is highly unusual in our area.

[donsutherland1]

As per Alex's question, here's how things look right now based on the historic experience with snowfall climatology.

At Boston, total snowfall to date (through January 22) is 49.6". That would be the 4th highest October-January figure if no additional snow fell this month. In New York City, the 36.1" to date would be the 6th highest October-January figure if there was no additional snow. However, a system will likely bring at least some snow and possibly rain in the Tuesday-Thursday timeframe (though I do note the GFS's out-to-sea idea).

To see where things might go from the historic perspective, I took a look at all seasons where October-January snowfall came to 30" or more in NYC and 40" or more in Boston. There were 10 such cases for each city.

Boston:

Mean seasonal snowfall: 79.0"

Median seasonal snowfall: 79.0"

Least: 58.5", 1976-77

Most: 107.0", 1995-96

50" or more seasonal snowfall: 100% cases

60" or more seasonal snowfall: 90% cases

70" or more seasonal snowfall: 60% cases

80" or more seasonal snowfall: 50% cases

Mean February-April snowfall: 30.0"

Median February-April snowfall: 27.7"

Least February-April snowfall: 16.6", 1976-77

Most February-April snowfall: 51.0", 1993-94

Less than 20" February-April snowfall: 20% cases

20" or more February-April snowfall: 80% cases

30" or more February-April snowfall: 40% cases

40" or more February-April snowfall: 20% cases

New York City:

Mean seasonal snowfall: 53.5"

Median seasonal snowfall: 51.4"

Least: 40.4", 1876-77

Most: 75.6", 1995-96

40" or more seasonal snowfall: 100% cases

50" or more seasonal snowfall: 50% cases

60" or more seasonal snowfall: 40% cases

Mean February-April snowfall: 16.4"

Median February-April snowfall: 16.6"

Least February-April snowfall: 5.5", 2003-04

Most February-April snowfall: 35.1", 1995-96

Less than 10" February-April snowfall: 30% cases

10" or more February-April snowfall: 70% cases

15" or more February-April snowfall: 50% cases

20" or more February-April snowfall: 20% cases

January Update:

Winter 2010-11 is well on its way toward producing the kind of significant seasonal snowfall that was suggested by the historic snowfall climatology in December. New York City should see 40" or more seasonal snowfall, and the January data suggests that 50" or more is possible. Boston should easily exceed 50" seasonal snowfall and snowfall there should exceed 60" based on the January data and perhaps reach or exceed 70".

[ayuud]

hey don with lake Erie almost frozen,do you still see any changes in synoptic storm tracks? all we had so far was clippers

[donsutherland1]

hey don with lake Erie almost frozen,do you still see any changes in synoptic storm tracks? all we had so far was clippers

Not at present. I do believe that the second half of February might allow for some more favorable synoptic tracks for the Buffalo area. This week's storm could be on the coast or just offshore, but the heaviest precipitation will likely remain to the south and east of Buffalo.

[Snow Wizard]

As someone who enjoys and looks forward to the warmth of Spring, I'm fearing that Spring is going to be very much delayed this year, and that March will continue the bitter cold for the east. The ponds around here have been frozen since around Thanksgiving (with no thaw at any time during the period), which is highly unusual in our area.

Nina climatology highly favors a cold west / warm east during the late winter and early spring, so there is still hope for both of us.

[Ottawa Blizzard]

Not at present. I do believe that the second half of February might allow for some more favorable synoptic tracks for the Buffalo area. This week's storm could be on the coast or just offshore, but the heaviest precipitation will likely remain to the south and east of Buffalo.

Don, i realize that 1992-93 was an El Nino year, and that it also considered one of the two "Mount Pinatubo winters", but do you see a more favourable storm track setting for eastern Ontario come mid February? Ottawa's snow blitz that winter goy started around the 12th-13th that year.

[FrederickWX]

Nina climatology highly favors a cold west / warm east during the late winter and early spring, so there is still hope for both of us.

That's true, but this winter season has been anything but typical. For the east coast, the negative AO/NAO has overpowered any effects that the Nina would normally have (as evidenced by the very cold January, and given the continued cold and stormy look to February), so I'm not sure what to think about March.

[Feb]

Nina climatology highly favors a cold west / warm east during the late winter and early spring, so there is still hope for both of us.

keep telling yourself this.

[Ottawa Blizzard]

Joe Bastardi seems to be hinting at a major arctic outbreak for around Valentine's Day. He showed a map of the tropopause and how there's warming over the pole and how this can hint at a big arcti outbreak down the road. Interestingly, he showed a map and said that the current situation (over the pole) looks similar to how it looked on December 20,1993. We all know what happened after that. He made a comparison to the January 3-23,1994 period, which, in keeping with his style, was one of the most extreme periods of arctic weather in recent decades.

[Snow Wizard]

keep telling yourself this.

This is pretty rude actually. All we want in the NW is some slice of the pie this winter. Is there anything wrong with that?

I am giving up on this winter. Now it's almost a whole year to wait before we might get something worthwhile. I sure hope something doesn't steal it from us next winter. Enjoy your endless cold and snow.

[Feb]

This is pretty rude actually. All we want in the NW is some slice of the pie this winter. Is there anything wrong with that?

I am giving up on this winter. Now it's almost a whole year to wait before we might get something worthwhile. I sure hope something doesn't steal it from us next winter. Enjoy your endless cold and snow.

I didn't realize stealing snow was even possible. And how much snow is being stolen from you?

[Rainman]

I didn't realize stealing snow was even possible. And how much snow is being stolen from you?

(Climatological average for snowfall during mod-strong la Ninas) - (Amount recorded so far this year) = stolen snow

1. Why are you not getting this?

2. Why are you still allowed to post here?

[Organizing Low]

(Climatological average for snowfall during mod-strong la Ninas) - (Amount recorded so far this year) = stolen snow

1. Why are you not getting this?

2. Why are you still allowed to post here?

[DFWWeather]

I'd be careful broad brushing Texas as being mild to above normal for February. The same was said for January and DFW is currently sitting at 3 BELOW normal for the month. I know this is atypical of La Niña, but this La Niña is running astray even down here. This is not likely to change much given the forecast for the last 7 days of the month. There doesn't appear to be strong enough warming to offset the cold anomalies. It is also looking cold heading into the first week of February. Huge bust potential if going for warmer than normal in Texas for the first part of February, especially for the northern portions of the state. In fact, December was only 2 ABOVE normal for DFW, and if February is below or neutral, I smell huge bust on all forecasts that called for way above nomal and a mild winter for northern Texas.

[donsutherland1]

I'd be careful broad brushing Texas as being mild to above normal for February. The same was said for January and DFW is currently sitting at 3 BELOW normal for the month. I know this is atypical of La Niña, but this La Niña is running astray even down here. This is not likely to change much given the forecast for the last 7 days of the month. There doesn't appear to be strong enough warming to offset the cold anomalies. It is also looking cold heading into the first week of February. Huge bust potential if going for warmer than normal in Texas for the first part of February, especially for the northern portions of the state. In fact, December was only 2 ABOVE normal for DFW, and if February is below or neutral, I smell huge bust on all forecasts that called for way above nomal and a mild winter for northern Texas.

Three quick things:

1. My January thoughts will likely prove to have been too warm for the Southern Plains, including much of Texas (especially the eastern half of TX).

2. Right now, I believe February will likely start cold, but end warm in TX, with the milder air in the latter half of the month tipping the scale somewhat in favor of the mild side of normal for the overall anomalies.

3. The milder overall anomalies should not be interpreted to indicate "blowtorch" type readings, though a few quite warm days could be possible toward the end of the month.

Of course, my thinking could prove "too warm" for TX as will likely be the case this month.

[DFWWeather]

Three quick things:

1. My January thoughts will likely prove to have been too warm for the Southern Plains, including much of Texas (especially the eastern half of TX).

2. Right now, I believe February will likely start cold, but end warm in TX, with the milder air in the latter half of the month tipping the scale somewhat in favor of the mild side of normal for the overall anomalies.

3. The milder overall anomalies should not be interpreted to indicate "blowtorch" type readings, though a few quite warm days could be possible toward the end of the month.

Of course, my thinking could prove "too warm" for TX as will likely be the case this month.

Well, its not just you but every forecast I've seen. Most are calling, or have called for, way above normal temperatures for Texas, and that hasn't verified, yet some are still calling for it. I've seen some forecasts as much as 6 above normal (which I can tell you now is not going to verify, at least not for DFW). Even the on-screen local weather personalities were calling for a mild winter. I just thought I'd point this out as a caution. We will just need to see how cold the departures are from normal the first of half of February. The warming that has tried to occur all winter hasn't been all that strong, and if blocking does develop like you say, I have my doubts. I believe this winter will probably end up being about neutral to sligtly below. Good luck on your forecast though!

Having said all that, I will point out that low temperatures, especially for DFW, have not been all that cold this winter. In a typical winter, we usually see lows drop below 20°F at least once, but we have not seen that this year (although we still could given forthcoming pattern). Looking back on our climatology (all the way back to 1898), we should see lows below 10°F every five years, we have not seen that in 15 years (February 1996 was the last time with temp of 8°F). Fifteen years is the largest stretch in our weather recorded history that temperatures have not been that cold.

[wxmx]

I'm with Don about the milder 2nd half of February for TX (not sure how warm, because a very strong -AO could alleviate that some). But if the early Feb cold shot that is being depicted by the models verify, specially the forecasts of the Euro and CMC, it will be very tough to go above normal, sans an epic late Feb torch.

[A-L-E-X]

That's true, but this winter season has been anything but typical. For the east coast, the negative AO/NAO has overpowered any effects that the Nina would normally have (as evidenced by the very cold January, and given the continued cold and stormy look to February), so I'm not sure what to think about March.

Also, you have to look at the nina weakening later in the season and then analogs like March 1956 come into play. Usually nina winter finish out with a cold and snowy March. I hope we all get in on the action.

[A-L-E-X]

Three quick things:

1. My January thoughts will likely prove to have been too warm for the Southern Plains, including much of Texas (especially the eastern half of TX).

2. Right now, I believe February will likely start cold, but end warm in TX, with the milder air in the latter half of the month tipping the scale somewhat in favor of the mild side of normal for the overall anomalies.

3. The milder overall anomalies should not be interpreted to indicate "blowtorch" type readings, though a few quite warm days could be possible toward the end of the month.

Of course, my thinking could prove "too warm" for TX as will likely be the case this month.

Don, do you see the end of Feb warming up for the rest of us also? I believe you were going for a cold March earlier.

Thanks for all the dataset updates on BOS and NYC snowfall-- I noticed something interesting-- while BOS has a smooth gradation of lower probabilities when moving up the snowfall scale, NYC has a much sharper gradient, going from 50% at 15" more to only 20% at 20" more..... is this the function of a more limited dataset? Based on this info, I would say NYC has a decent shot at 50" or slightly more-- probably close to what we had last winter and thus making it only the second couplet of 50-50 winters (the other one was 1916-17 and 1917-18 as has already been noted.) Right now I would go with something like 55" of snow for NYC and 80" for BOS

[pcbjr]

Don,

Any updated thoughts on the AO and NAO after Feb 1st? The Ensemble Mean Outlooks seem to rising after that, but the GFS seems to have them falling (per the CPC website).

Thanks!

[donsutherland1]

Don,

Any updated thoughts on the AO and NAO after Feb 1st? The Ensemble Mean Outlooks seem to rising after that, but the GFS seems to have them falling (per the CPC website).

Thanks!

Right now, I have no changes to my thoughts. There are wildcards e.g., if a sudden stratospheric warming takes place and then what its impact might be. The divergence between the operational GFS and ensemble means highlight the uncertainty on the modeling right now. In about a week, the picture should be much clearer.

[pcbjr]

Right now, I have no changes to my thoughts. There are wildcards e.g., if a sudden stratospheric warming takes place and then what its impact might be. The divergence between the operational GFS and ensemble means highlight the uncertainty on the modeling right now. In about a week, the picture should be much clearer.

Thanks, Don!

You are truly a gentleman.

Please keep the posts coming (and I know the folks up north want snow, snow, snow - but some of us down here at least want continued cold/below normal through Feb., {though I'd take an 1899 snowstorm in a second!!!}, so if you see any hope for us not going into warmth this away for a few weeks, please fly the flag!!!!).

Regardless of what the pattern ultimately brings, I'll keep learning from what you put out!

Best Regards,

pcbjr

[A-L-E-X]

Right now, I have no changes to my thoughts. There are wildcards e.g., if a sudden stratospheric warming takes place and then what its impact might be. The divergence between the operational GFS and ensemble means highlight the uncertainty on the modeling right now. In about a week, the picture should be much clearer.

Not that I put much stock in them forecast but WSI's new February forecast calls for above normal temps in the east and below normal in the west, especially the Pac NW. Snow Wizard and Mallow would love that outlook, so I thought I'd throw it out there for them. They have a return back to a December and January kind of pattern for March and April and said March was likely to be snowy in the east..... FWIW.

[A-L-E-X]

Thanks, Don!

You are truly a gentleman.

Please keep the posts coming (and I know the folks up north want snow, snow, snow - but some of us down here at least want continued cold/below normal through Feb., {though I'd take an 1899 snowstorm in a second!!!}, so if you see any hope for us not going into warmth this away for a few weeks, please fly the flag!!!!).

Regardless of what the pattern ultimately brings, I'll keep learning from what you put out!

Best Regards,

pcbjr

I would love to live to see something like that again. IMO Feb 1899 was rarer than March 1993-- just look at the extent of the heavy snow southward plus the extreme arctic outbreak that followed!

35" in Cape May NJ..... amazing! But the foot plus amounts in the deep south maybe even more so.

[Ottawa Blizzard]

Don, what are your overall thoughts for Ottawa for February? It's looking to be very cold the first week of February according to the models. Joe Bastardi hinted yesterday that stratospheric warming over the pole could be hinting at a very cold pattern for the Valentine's Day period as well. Do you agree with his thoughts? The Februaries to beat in Ottawa are 1993,1979,1967 and of course the legendary, probably untouchable, 1934.

[pcbjr]

I would love to live to see something like that again. IMO Feb 1899 was rarer than March 1993-- just look at the extent of the heavy snow southward plus the extreme arctic outbreak that followed!

35" in Cape May NJ..... amazing! But the foot plus amounts in the deep south maybe even more so.

would love to live to see something like that again. Ditto!

My family hails from the Deep South since the 1700's, and the generational verbal legend is that it happens "once in a 100 years or so" - who can tell? (Last I heard from an old Great Uncle about 30 years ago was the "white rain fell and didn't leave"). All we need is a block, a Gulf Low, and some STRANGE other things happening.

[NortheastPAWx]

DS -- How about storm tracks and setups? Do you think we'll see a classic one where everyone cashes in instead of these tight gradients and a stone's throw from 2 inches to 2 feet?