Nikolai's Winter 2011-12 Forecast

[Nikolai]

First of all, my forecast for last winter:

http://fortysouthwx....010-11-forecast

My own subjective grading for the numbers from last winter, in bold

DCA (snow numbers at IAD):

December: -2.5, 5-10"

January: -1, 10"

February: +2, 0-2"

March: 5"

Snow: 15-20" (IAD: 20-25")

I did very well on temperatures, however I was overly optimistic with regards to snow for March (December fell slightly short). I'd give my December a B+, January an A, and February an A. March was a fail, but I don't really care about March.

Overall: B+

NYC:

December: -3, 10-15"

January: -3, 10-15"

February: +1.5, 0-5"

March: 5-10"

Snow: 30-35"

My forecast for NYC did better than mine for DC. December through February get As, and again, a fail for March (but again, March is stupid anyways). I underestimated the snow, but the overall thought was for a snowy winter relative to normal, and the snow fell when I expected it to (again, besides March).

Overall: A-

Now, for my forecast this year!

While ENSO has weakened blocking has remained strong, and we've seen a fairly dominant -AO this summer. The NAO has fallen dramatically since spring as well, and has been negative since early June.

This is very clearly a continuation of the pattern we have seen the past several summers, where blocking has been very prevalent (there is a thread in the Mid-Atlantic subforum, and each summer since 2007 has featured rather prominent blocking). Perhaps it's because of the solar minimum--who really knows--but, it has occurred and continues to do so.

While summer blocking in itself isn't particularly great (woohoo, we get hot... boring...), the fact that blocking has had so much staying power is a positive sign for the upcoming winter, in my opinion. I think we may have finally entered another cycle where the -NAO predominates rather than the +NAO, which is truly great news for people who enjoy cold and snow.

Besides the continuation of blocking, ENSO is another major factor. We're coming out of a strong Nina right now, but it looks like we may see either negative neutral or weak Nina conditions for the coming winter. Historically, weak Ninas have been rather decent for the NYC area.

Two other trends are very important to note.

The first is just how wet NYC has been for the past decade or so. Last year was the first since 2002 to not see 50" of rain (just missed the mark at 49.37"), but this year seems on track to possibly hit 50" once more, with almost 32" so far this year. A wetter climate means more opportunities for snow by default, since more precipitation falling means there are more chances it falls while the weather is cold, however we've also seen an obscene number of KU storms recently. It doesn't take a genius, but one of the major reasons for this could be that we're seeing the renewed blocking pattern coinciding with an increase in precipitation for NYC, so storms that do occur may have a better shot at producing more QPF (for whatever reason).

The second is something I talk about every year--the changing snowfall normals, particularly for December. Since 2000, 7/11 Decembers have seen 6"+ at Central Park, with 5 of those seeing 10"+. Decembers have become significantly snowier over the past decade or so, and I don't see why that shouldn't continue for the short-medium term (obviously these things do change, however the shift to snowier Decembers only happened very recently after snowless Decembers from the 70s-90s).

Primary analogs: 08-09, 62-63, 56-57

With that, the #s for the upcoming winter:

NYC

December: -1, 5-10"

January: -3, 10-20"

February: +2, 0-5"

March: 5"

Total snow: ~30"

By far the biggest signal I'm seeing is for a cold January that will likely be snowy as well. December is a bit of a toss-up, but given recent history I think it's wise to go for relatively robust snow numbers and slightly below normal temperatures. I don't see February being promising at all, although Ninas do tend to produce one or two late season events through March.

[CAT5ANDREW]

I like your snow totals.I would go colder on the temps as second year ninas usually are colder.Overall a decent forecast.

[ag3]

Nice writeup.

[MJO812]

Great writeup.

A lot of people are saying that this winter will most likely be similiar to 2008-2009. That winter wasn't bad at all. A lot of nickel and dimes events in January and a decent size storm in March.

[nzucker]

I really like your analogs, I could see the La Niña being a bit stronger than 62-63 or 08-09 (and take into account that 62-63 was following a neutral year, not a moderate/strong La Niña like Winter 11-12 or Winter 08-09.) January 1957 was very cold (28.5F at KNYC), and January 1963 was moderately cold (30.1F), and we had the frigid January in 08-09 (27.9F)...good thoughts!

[A-L-E-X]

I really like your analogs, I could see the La Niña being a bit stronger than 62-63 or 08-09 (and take into account that 62-63 was following a neutral year, not a moderate/strong La Niña like Winter 11-12 or Winter 08-09. January 1957 was very cold (28.5F at KNYC), and January 1963 was moderately cold (30.1F), and we had the frigid January in 08-09 (27.9F)...good thoughts!

Something I noticed with his analogs, and something I have been harping on for months now-- every winter after his analog years were el ninos, and quite strong ones at that. I continue to expect an el nino of significant intensity for 12-13. That will be our next big snow season

[uncle W]

I really like your analogs, I could see the La Niña being a bit stronger than 62-63 or 08-09 (and take into account that 62-63 was following a neutral year, not a moderate/strong La Niña like Winter 11-12 or Winter 08-09. January 1957 was very cold (28.5F at KNYC), and January 1963 was moderately cold (30.1F), and we had the frigid January in 08-09 (27.9F)...good thoughts!

the MEI was quite low in 1961-62...I

http://www.esrl.noaa.gov/psd/enso/mei/table.html

[Isotherm]

Re your primary analogs, I understand 56-57 and 08-09 as those were both post mod/strong Nina years, and had relatively similar states of the Pacific and Atlantic to now. However, not sure I get 62-63; it was weak nina following neutral ENSO (61-62) and the AMO was in the process of flipping to a negative state. Given the more advanced stage of the -PDO and the cooling Atlantic during that time frame, I have to think 62-63 is too brutally cold of an analog for what's in store next winter. Not saying it can't happen, but atm 62-63 is a pretty bold analog choice given it featured severe cold temps Dec, Jan, and Feb (around -5, -3, and -5 departures respectively for NYC area).

I agree with much of the NAO portion, and used the solar state heavily in my winter forecast for the past winter, which turned out well in expecting the blocking. The big question in my mind is will the sun remain quiet over the next several months, and if so, will the NAO continue to be negative after being predominately negative for 3 consecutive years now. I generally like to wait a couple more months before looking at things closer.

[Nikolai]

Re your primary analogs, I understand 56-57 and 08-09 as those were both post mod/strong Nina years, and had relatively similar states of the Pacific and Atlantic to now. However, not sure I get 62-63; it was weak nina following neutral ENSO (61-62) and the AMO was in the process of flipping to a negative state. Given the more advanced stage of the -PDO and the cooling Atlantic during that time frame, I have to think 62-63 is too brutally cold of an analog for what's in store next winter. Not saying it can't happen, but atm 62-63 is a pretty bold analog choice given it featured severe cold temps Dec, Jan, and Feb (around -5, -3, and -5 departures respectively for NYC area).

I agree with much of the NAO portion, and used the solar state heavily in my winter forecast for the past winter, which turned out well in expecting the blocking. The big question in my mind is will the sun remain quiet over the next several months, and if so, will the NAO continue to be negative after being predominately negative for 3 consecutive years now. I generally like to wait a couple more months before looking at things closer.

I didn't go anywhere near as cold as 62-63, I just like it as a general analog. I highly doubt we will be as dry as the winters during the 60s, as well. 56-57 and 08-09 are definitely better, though.

I also doubt we see any particularly large storms this winter--just not feeling it at this point. I think we could manage one storm of up to 8" or so but the snow should generally come in relatively minor/moderate events (a bunch of events around 2-4", potentially one event of 6-8"). I don't think that precludes generous snow cover throughout a portion of the winter though, and January/late December could be very fun.

[nzucker]

I didn't go anywhere near as cold as 62-63, I just like it as a general analog. I highly doubt we will be as dry as the winters during the 60s, as well. 56-57 and 08-09 are definitely better, though.

I also doubt we see any particularly large storms this winter--just not feeling it at this point. I think we could manage one storm of up to 8" or so but the snow should generally come in relatively minor/moderate events (a bunch of events around 2-4", potentially one event of 6-8"). I don't think that precludes generous snow cover throughout a portion of the winter though, and January/late December could be very fun.

You're also looking at a lot of +QBO winters...how about considering the weak Niña/-QBO combination more and looking at years like 00-01 and 83-84? The -QBO/Niña winters like 00-01 and 70-71 also suggest a strong latitude gradient, so you might even go a bit lower for NYC if you think that it's going to be a more northern storm track...What made you go against these analogs in favor of some years that had an opposite stratospheric signal, or even a different solar signal like 56-57?

[Nikolai]

You're also looking at a lot of +QBO winters...how about considering the weak Niña/-QBO combination more and looking at years like 00-01 and 83-84? The -QBO/Niña winters like 00-01 and 70-71 also suggest a strong latitude gradient, so you might even go a bit lower for NYC if you think that it's going to be a more northern storm track...What made you go against these analogs in favor of some years that had an opposite stratospheric signal, or even a different solar signal like 56-57?

Both of the years you mentioned lacked extensive summer blocking.

[HailMan06]

Don't know about you guys, but I'm syched about the winter.

Four months until winter.

[Isotherm]

Don't know about you guys, but I'm syched about the winter.

Four months until winter.

Yeah my mindset is gradually shifting winter now. Give me a few more weeks of summer and I'll be good.

I think of it this way --

1) Days and nights become equal by late Sept - a big benchmark

2) First frost - usually by mid October

3) Color change / leaf drop - late October

4) First hard freeze and DST - early November

5) First flakes - by mid November

Then home free.

We've already crossed off a few checkpoints, and that's sunset pre 8pm, crickets out, and ragweed season onset.

[Guest Pamela]

2) First frost - usually by mid October

Except at LGA, where it is usually around December 31st....

[Isotherm]

Except at LGA, where it is usually around December 31st....

Yeah they'll probably have 6" of snow on the ground before they've been below 32.

[Guest Pamela]

Yeah they'll probably have 6" of snow on the ground before they've been below 32.

Seriously, the last few years, there were several times when the first snowflakes and the first freezing temps were concurrent happenings...

[HailMan06]

Yeah my mindset is gradually shifting winter now. Give me a few more weeks of summer and I'll be good.

I think of it this way --

1) Days and nights become equal by late Sept - a big benchmark

2) First frost - usually by mid October

3) Color change / leaf drop - late October

4) First hard freeze and DST - early November

5) First flakes - by mid November

Then home free.

We've already crossed off a few checkpoints, and that's sunset pre 8pm, crickets out, and ragweed season onset.

Well, before winter comes I would like our region to get in on some tropical storm/hurricane activity before the warm season is out.

[ORH_wxman]

Seriously, the last few years, there were several times when the first snowflakes and the first freezing temps were concurrent happenings...

Its happened here the last two years...10/23/10 (trace of snow) and 10/16/09 (1.4" of snow). Didn't quite pull it off in 2008, had a 31F reading on the 23rd of October, but the 2nd reading below freezing came on Oct 28th during snow.

[A-L-E-X]

Its happened here the last two years...10/23/10 (trace of snow) and 10/16/09 (1.4" of snow). Didn't quite pull it off in 2008, had a 31F reading on the 23rd of October, but the 2nd reading below freezing came on Oct 28th during snow.

I remember back in 01 or 02 I think (maybe both lol) we actually had snow on October 30th in the daytime with temps in the mid 30s and didn't get our first freeze until two weeks later lol. The earliest I ever remember seeing a freeze here is actually October 30 (same for snowfall.)

[ORH_wxman]

I remember back in 01 or 02 I think (maybe both lol) we actually had snow on October 30th in the daytime with temps in the mid 30s and didn't get our first freeze until two weeks later lol. The earliest I ever remember seeing a freeze here is actually October 30 (same for snowfall.)

We had snow here on Sept 30, 1992, but the temp never dropped below freezing. I think it got to 33F that day. Earliest snow obs on record here.

[A-L-E-X]

We had snow here on Sept 30, 1992, but the temp never dropped below freezing. I think it got to 33F that day. Earliest snow obs on record here.

That's pretty special-- I've never witnessed snow that early, not even in the Poconos. I did witness the strangest thing I have ever seen back in May 1996-- after a long and snowy winter, we thought we were safe in the middle of May, so I was helping my sister out with planting on her property out in the Poconos and the temp was in the 80s. Well, that night this big severe storm hit, knocked a tree down in her yard and the next morning everything was covered in white! And it wasn't insubstantial-- there was like 2-4 inches of snow covering everything when it had been in the 80s the day before and there had been severe storms overnight! We had a frost the next morning even in my part of western Long Island (the frost was so thick, with temps around 33-34, that it actually looked like snow) and then a week later we were in the upper 90s, the hottest temps we would see for that entire year!

[ORH_wxman]

That's pretty special-- I've never witnessed snow that early, not even in the Poconos. I did witness the strangest thing I have ever seen back in May 1996-- after a long and snowy winter, we thought we were safe in the middle of May, so I was helping my sister out with planting on her property out in the Poconos and the temp was in the 80s. Well, that night this big severe storm hit, knocked a tree down in her yard and the next morning everything was covered in white! And it wasn't insubstantial-- there was like 2-4 inches of snow covering everything when it had been in the 80s the day before and there had been severe storms overnight! We had a frost the next morning even in my part of western Long Island (the frost was so thick, with temps around 33-34, that it actually looked like snow) and then a week later we were in the upper 90s, the hottest temps we would see for that entire year!

Maybe the 1992 September snow was a harbinger of things to come. (December 1992)

[A-L-E-X]

Maybe the 1992 September snow was a harbinger of things to come. (December 1992)

That was the huge pattern change for you-- the 1992-93 winter changed almost a decade of snowfall futility. Even though it wasn't a big snowfall season here, some of those moderate sized events were overperforming and that winter was like a lead in for what was to come.

[nzucker]

Its happened here the last two years...10/23/10 (trace of snow) and 10/16/09 (1.4" of snow). Didn't quite pull it off in 2008, had a 31F reading on the 23rd of October, but the 2nd reading below freezing came on Oct 28th during snow.

I chased the 10/16 storm in the Poconos; that was an extremely anomalous event, 0C 850mb temperatures well into Florida in mid-October, but that was the result of a powerful Kelvin Wave that brought the El Niño to strong status. I made a last minute decision to chase the storm at our vacation home in the Poconos. It ended up a bit of a disappointment because my house at 1500' next to a warm lake did not accumulate more than a light dusting of snow, but the hiking was great as the foliage was just past its peak, and all the trees above 1800' or so were coated with heavy, wet snow. The forest mix up there is mostly maple, birch, and some beech, so it tends to be very beautiful in the fall. There was a stark contrast between mixed precipitation splatting on the windshield driving through lower elevations on Route 370 to extremely heavy snow on the ridgelines, which are around 2200' in most areas. I never found the trail to the highest mountain in the area, which I believe is called Sugarloaf and stands at 2600', but I got far enough up the ridges to see 3" of snow on the ground on October 16th. The world was 100% white above 2000'....at 1800', it was a slushy mess, and at 1500' there was nothing but rain with the occasional mangled snowflake that takes you 10 minutes and a strong flashlight to notice. State College had 6" of snow from that storm, I believe.

We had snow here on Sept 30, 1992, but the temp never dropped below freezing. I think it got to 33F that day. Earliest snow obs on record here.

Was that the day BTV also had its only September snowfall? I know they've recorded one snowfall in September, not sure of the year though. The earliest snow I remember well in Middlebury was 10/28/09, which was a large storm in which parts of the Adirondacks like Old Forge received up to 16" of snow. In Fall 2006, we did have a snow event in early October that left a skiff of snow on campus....it was mostly rain but changed briefly to heavy snow, leaving the lightest of accumulations, maybe 0.1" if you're a slant-sticker like Kevin, if that's even possible to do with so little. The latest snowfall I experienced on campus was 4/27/2010....the campus was already leafed out, and 3 days later, it was pushing 85F as the hottest summer on record began.

[ORH_wxman]

That was the huge pattern change for you-- the 1992-93 winter changed almost a decade of snowfall futility. Even though it wasn't a big snowfall season here, some of those moderate sized events were overperforming and that winter was like a lead in for what was to come.

It was an incredible break in fortune and its continued ever since despite the late 90s hiatus. Those were quickly overshadowed by some monster winters in the early 2000s (most notable 2000-2001 here). The 1980s were so putrid for snow that most of the younger people here (under age 25) will never understand it until it happens again (and it will happen again). You can look at the numbers and think you know what its like, but you truly will not get it until you experience it.

[nzucker]

That was the huge pattern change for you-- the 1992-93 winter changed almost a decade of snowfall futility. Even though it wasn't a big snowfall season here, some of those moderate sized events were overperforming and that winter was like a lead in for what was to come.

NYC recorded its first 10" snowfall in 10 years in March 1993. Central Park hadn't had a ten inch storm since the Megalopolis Blizzard of February 1983.

It's incredible to think of such a long drought, as Central Park has had 5 storms over 10" in the last 2 winters...here they are:

12/19/09: 10.9"

2/10/10: 10.0"

2/25/10: 20.0"

12/26/10: 20.0"

1/27/11: 19.0"

They just missed a sixth 10" storm with 9.1" on 1/12/11....I had 14.5" in that storm as the tail end of the CT superband smoked Westchester County, especially the central areas. Contrary to the experience of most people in the NYC forum, that was the best storm of the winter for Dobbs Ferry. We live in glorious times!

[CAT5ANDREW]

It was an incredible break in fortune and its continued ever since despite the late 90s hiatus. Those were quickly overshadowed by some monster winters in the early 2000s (most notable 2000-2001 here). The 1980s were so putrid for snow that most of the younger people here (under age 25) will never understand it until it happens again (and it will happen again). You can look at the numbers and think you know what its like, but you truly will not get it until you experience it.

I lived through the 1980s and they were horrible with snowfall here,but there were some decent cold shots,even in the milder winters.

The worst period for me was 1996-97 through 2001-02 winter.4 out of 5 winters in the top 10 warmest and least snowfall of all time with 2001-02 being #1 in temps and #2 with low snow totals.I dont believe we ever see that combination again around here.

[CAT5ANDREW]

That was the huge pattern change for you-- the 1992-93 winter changed almost a decade of snowfall futility.  Even though it wasn't a big snowfall season here, some of those moderate sized events were overperforming and that winter was like a lead in for what was to come.

I had 1.3 inches mild temps for the first 2 months of that winter.FEB 1 1993,the pattern to cold and eventually snowier began and I had 27 inches the rest of the winter.

[A-L-E-X]

I lived through the 1980s and they were horrible with snowfall here,but there were some decent cold shots,even in the milder winters.

The worst period for me was 1996-97 through 2001-02 winter.4 out of 5 winters in the top 10 warmest and least snowfall of all time with 2001-02 being #1 in temps and #2 with low snow totals.I dont believe we ever see that combination again around here.

I dont know man-- it was just as bad as the 22/24 months above normal in the early 90s. We had a cold and snowless December 1989 so I wont even count that was being "wintry" but Jan 90 and Feb 90 had to be the warmest couplet of winter months I've ever experienced and they were followed by upper 80s in the middle of March in 1990. Who needs to go south for spring break when spring break came north? lol We were all in shorts and tshirts in March back then.

[A-L-E-X]

NYC recorded its first 10" snowfall in 10 years in March 1993. Central Park hadn't had a ten inch storm since the Megalopolis Blizzard of February 1983.

It's incredible to think of such a long drought, as Central Park has had 5 storms over 10" in the last 2 winters...here they are:

12/19/09: 10.9"

2/10/10: 10.0"

2/25/10: 20.0"

12/26/10: 20.0"

1/27/11: 19.0"

They just missed a sixth 10" storm with 9.1" on 1/12/11....I had 14.5" in that storm as the tail end of the CT superband smoked Westchester County, especially the central areas. Contrary to the experience of most people in the NYC forum, that was the best storm of the winter for Dobbs Ferry. We live in glorious times!

And March 1993 wasn't even a true "snowstorm" for us-- the 1993-94 winter had all snow snowstorms in February, but for me, I didn't get my first big all snow snowstorm of the 90s until January 1996.