raindancewx

I've been looking hard at Spring 1979 as an analog lately just because it a) followed two El Ninos that were weak with fairly low solar conditions (1976-77, 1977-78) b) It is a cold ENSO winter that had a super +NAO in Nov transition to pretty negative in Dec-Jan. c) Vaguely looks like February nationally for temperatures (in the Eastern 2/3 of the US, and if warmed up a bit) I don't consider 1979-80 an El Nino. It's borderline - I think it's about the limit on the warm side for what we could see next winter. I lean toward flat Neutral with Nino 4 staying fairly cold but we'll see.

Very curious to see how this changes by say, 2/1-2/16, for Texas, New Mexico and Colorado. This month will undoubtedly finish pretty cold nationally. By the end though, should be a lot warmer than even a month as recent as February 2019. CPC has the final week of February favored warm for most of the US. The cold in Billings and Bismarck and the north-central is still forecast to relax a lot in a few more days, generally after 2/17.

Every time I look here, the storm timing moves up a bit faster. I like snow. What I really want though is the cold front to be through by Midnight Sunday so we don't have a high of 42F on a day when it is 18F or something in the afternoon.

The Jamstec tries to develop a weak El Nino from the east in Spring on the new update. But it then collapses in Fall. Very similar to 2012.

The funny thing about this pattern is extremely far south snowfall has been a feature since September. It snowed down to Santa Fe (they had an inch) on 9/9/2020. Then you had this, and it got deeper toward Mexico on 10/28. So these big cold/snow outbreaks have been advertised. I'm pretty sure the WPO flipped back negative for the first time since October and that's part of why it is happening again (that and the strat warm stuff).

Looks like a pretty historic cold outbreak and snow storm is coming for Texas and eastern New Mexico the coming days. Albuquerque probably won't drop below 0F, but we should get some snow. Weather.com has accumulating snow down to Houston. Even with the cold coming deep into Texas, I'm not sure they'll end up cold for the month. El Paso has been hanging out around +10 to date in February. After the next week or so, much of the severe cold in the center of the US should get destroyed as Canada warm ups and the mechanisms that have brought the cold in relax. I had a cold February in the northern US, so the month is fairly close (if more severe) to what I had in mind. There is some fairly intense cold in the Northwest right now too, so the warmth in OR/WA is getting attacked. The temperature pattern of February has really snapped a lot of the US pretty quickly toward my analog blend. Places that were really far out like Billings, Rapid City, and Minneapolis are fairly close now, and will continue to improve for at least the next five days. The deeper you get into a season, the harder it is for individual days to meaningfully change the seasonal average. So it's been amazing seeing places snap 0.5F or more closer - for the season - each day in the North Central US.

As a general rule, if Albuquerque gets snow in March or April, you tend to get tornadoes east of us, since the normal heat here (~60s-70s) is blown east but over sea-level places where it warms to the 80s. Cold rain is usually good enough too if we are in the mid 30s to low 40s in April or May. I'm mostly putting out the timing for when I expect the tornado outbreaks just to see if I get even close. What I did in the forecast is include looks for when NM is cold, and then compare those looks to temperature profiles in tornado outbreaks in the analogs. The looks are similar. So the idea is if I can time when New Mexico is cold with a storm, it might work for identifying an outbreak.

https://www.scribd.com/document/494132283/Spring-2021-PDF I got tired of waiting for the January 2021 CPC update for the Tropical Pacific. That is my Spring 2021 outlook. Basic idea is a blend of Spring 1955, 2008, 2012 for the La Nina, but Spring 1979 is added for the unusual (near record) +NAO November to consistently -NAO Dec-Jan in a cold ENSO. That transition is very unusual. I'm expecting several big tornado outbreaks, two Plains blizzards, and one final big Nor'easter in mid-March. There is a good signal for cold shots into the Southwest US mid-March and late-April. Those are my guesses for timing the big tornado outbreaks. I've laid out the justifications in the forecast. I won't rehash it all here.

The pattern really isn't changing too much. It's just relaxing. It's hard to sustain the level of cold the Plains has been seeing.

Sunday (and maybe Tuesday) look promising for snow out here. My guess is the system Sunday over NM will be the system that ends the severe cold pattern nationally. Not that the whole country will warm into the 80s overnight. But the 20-40 degree below average temperatures won't last too much longer. Some pretty impressive cold is actually coming into the Northwest too.

The monthly data from CPC isn't in yet. Usually is by now. Think they are probably updating everything to the new 30-year normals (1991-2020). For now, more warming. Nino 1.2 averages are cold-neutral for the past month now. Nino 3 is averaging -0.5 for the past month. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 30DEC2020 22.2-1.3 24.4-1.0 25.4-1.2 27.3-1.2 06JAN2021 23.1-0.8 24.7-0.8 25.5-1.1 27.1-1.3 13JAN2021 24.0-0.3 24.7-0.9 25.4-1.2 27.0-1.3 20JAN2021 23.9-0.8 25.2-0.6 25.5-1.1 26.9-1.4 27JAN2021 24.6-0.5 25.7-0.2 25.9-0.7 27.1-1.1 03FEB2021 25.3-0.2 25.8-0.3 26.0-0.7 27.2-1.1

I wrote that on 1/22. NYC hit 60F in late December and then 50F in early January. It's nowhere near a top three streak for not hitting 50F in Central Park currently. Even as recently as 2015 NYC went over 60 days without hitting 50 degrees. There were also much longer streaks in 2004 and 2007. Number of Consecutive Days Max Temperature < 50 for New York-Central Park Area, NY (ThreadEx) Click column heading to sort ascending, click again to sort descending. Rank Run Length Ending Date 1 77 1969-03-15 2 65 1977-02-10 3 63 2015-03-08 4 62 1941-03-02 5 59 1948-02-13 6 54 1971-02-11 7 50 1981-02-01 8 47 2004-02-20 11 46 1968-03-07 12 45 1945-02-15 13 44 2007-03-01 17 43 2001-01-29 18 42 2011-02-13 20 39 2010-03-05 21 38 1958-03-01 22 37 1986-03-04 23 36 1947-03-12 25 35 2021-02-06 - 44 1996-01-17 - 47 1985-02-18 - 44 1978-03-11 - 47 1970-01-28 - 44 1956-02-07 - 42 1936-02-24 - 36 1935-02-15 Albuquerque had a streak from 11/24-2/1, 70 days in a row - without hitting 60F. My point was a lot of much colder climates hit 60F in that time frame. New York may do well for snow this month. I'm skeptical that Philly and south are going to do well. I had thought NYC would be on the borderline of the good snow areas. Essentially, with the NAO staying negative into January that area shifted south of where I expected.

The GFS has something for NM/CO snow around 2/13-2/15 which makes sense to me. It is in line with the timing of the most recent SOI crash. I'm actually pretty optimistic for about a three week period from 2/22 to 3/15 for snow in New Mexico and Colorado. I don't really expect much before or after that. But it is possible I have the timing a bit off. The years that have had measurable snow in Albuquerque in October have each had snow the following March. The favored dates tend to be around 3/10, which is consistent with the only time frame we've been able to get rain or snow in the city in the past eight months or so. The ten years with measurable October snow in Albuquerque average four measurable snows 2/22 to 3/15. 7/25-9/8-10/26-12/10-1/25--->3/10? That's essentially the storm cycle this La Nina for Albuquerque. There has also been a strong recurring tendency for big dumps of cold highs to come around day 25-30 of each 46 day cycle starting July 1, 2020. Albuquerque is essentially in the August/November portion of the cycle for now, where it seems like it should be pretty warm generally. The Sept/Dec portions were much more balanced, with a lot of cold and warmth, and that's likely to return in March. This is what I have for the high cycle in Albuquerque. Each number is the high minus the average. You can see pretty clearly the blues have concentrated at the some point in the cycle. Generally each cycle correlates to one or several prior cycles at an r-squared of about 0.2 to 0.5.

Philadelphia only got 0.7 inches of snow today. Less for DC/Baltimore. That's consistent with the pattern of marginal temperatures (never dropped below freezing in Philadelphia today - that seemed pretty likely given the warmth yesterday) that's been there and south of Philly all winter. The snow totals for much of the east are near average or below for the date, despite a small area from central New England to NYC and North Central PA doing pretty well. My big theory for this winter has been that the cycles are well established at about 45-days. So the big Nor'easter cycle is: late Oct-->mid Dec-->2/1-->mid March. Not really expecting any huge snow dumps until then. We'll see though. Temperatures start to climb as you get later in February even as the oceans are still getting colder. There was a lot of small crap that never really materialized as big snowstorms for the NE between mid-Dec and 2/1. That's where we are now I think.

It's amazing how hard my maps are going to snap toward 2020-21 with the current/coming cold in the Plains. The warmth for this winter is going to get beaten back pretty hard. In the end, it looks like 2007-08 was a pretty decent analog to this year, despite a lot of timing issues. You can see that there was a major cold dump into the Plain in February 2008. Unlike that year, the core of it seems to be 2/7-2/20 or so, but we'll see how it goes. We're just now getting to the point where the Northern Plains are about to flip below average for February temperatures.

I was trying to remember if the early part of February 2019 started off warm in Bismarck and Billings before the bottom fell out for temperatures. They did have a few warm days up there that month. Not expecting Billings to finish 22 below average like that incredible month. But the cold coming is pretty severe. Just the past couple days of cold has already moved 2020-21 a lot closer to my analog blend, wiping out 10-30% of the distance between the highs my blend had and the actual highs in some spots in the North Central.

Euro still has the La Nina ending in March. In April, both Nino 4 and Nino 3.4 are forecast by most ensemble members to rise above the blue line, which is -0.5C / La Nina.

Looks to me like the WPO was at record positive levels in January. AO/NAO were very negative with the EPO negative (which CPC considers the warm phase for the East as you can see in the correlation image). PNA neutral. Pacific wins. https://psl.noaa.gov/data/correlation/wp.data

February has started off cold in the south, mixed in the Northeast and warm elsewhere. CPC is unusually confident in the major cold snap advertised on the models. I've been running too cold all winter in the North-Central US, so this should drag the anomalies of 2020-21 a lot closer to my analog blend. I did have the North, and the East, outside the deep south fairly cold in February, so this is all fine by me.

The ONI for NDJ came in at -1.18C against the 30-year baseline CPC uses. Against 1951-2010 averages, I get -1.03C. So still two full three-month periods in a row at moderate status by historical standards. Both Oct-Dec and Nov-Jan qualify. Worth noting though: The reading for January in Nino 3.4 is 25.56C. It was 25.57C in January 2018. So it isn't like this La Nina is of vastly different strength to that one. It certainly was much stronger in the Fall. Obviously 2020-21 is much colder in Nino 4 too, while 2017-18 was much colder in Nino 1.2/3. My winter blend had January at -0.85C against the 1951-2010 average, and the observed was -0.89C. So this event is progressing as expected. Nino 4 and the other monthly data should be in soon.

Nino 3 isn't really cold enough to be considered a La Nina now. But Nino 3.4 is - although it warmed to above -1.0C in January on the 1981-2010 comparison. Nino 4 cooled. I'm expecting the monthly data to be 25.6C or so in Nino 3.4, around -0.9C for 1951-2010 averages. Not really that cold. But the waters in Nino 4 still look like they'll be around 27.0C, which is very cold for that zone.

My forecast was pretty good in the South in January and pretty good in the interior West in December, with NM/TX, most of the South and Northeast and eastern Midwest good both months. If the February pattern is cold in the NW/Northern Plains/Midwest, warm in the South as is forecast, should be a pretty good for highs nationally for the season even though I screwed up the progression to some extent. Big miss will be the Northern Plains. My snow outlook for the Northeast is interesting. Philadelphia reported 6.1" total for 1/31-2/1. They'll probably get more 2/2, but not too much. NYC reported 16.8" for 1/31-2/1. Boston was supposed to be above average for the season, and Logan got 1.2" or something. Baltimore/DC are still running well below average seasonally at the three airports as I had them. I'd say I'm still fine in Boston, DC, and Philadelphia. For the moment, Central Park has 27.4" for the season, while Boston has 24.3" - that's unusual, especially since Philly is at 12.7". This storm busted my snow outlook for NYC, ~23". They'll get a bit more 2/2 and then anything else later on. But it hasn't for Washington, Baltimore, or Boston. Philadelphia may bust with the next storm, but the pattern seems to be they get screwed with mixes. They reported 12-18 hours of freezing rain, and are now seeing above freezing light snow as I type this. So presumably if the next storm comes later in February or March, it won't add too much to their total. Not optimistic for DC/Baltimore either.

The weeklies have caught up to the look on the Tropical Tidbits map. A lot of weakening this week. If Nino 4 continues to warm up too, this event is going to end fairly soon, at least for a bit before resuming. The Eastern zones have warmed out of a La Nina this week. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 30DEC2020 22.2-1.3 24.4-0.9 25.4-1.2 27.3-1.1 06JAN2021 23.1-0.8 24.7-0.8 25.5-1.1 27.1-1.2 13JAN2021 24.0-0.3 24.7-0.9 25.4-1.2 27.0-1.3 20JAN2021 23.9-0.8 25.2-0.6 25.5-1.1 26.9-1.4 27JAN2021 24.6-0.4 25.7-0.2 25.9-0.7 27.1-1.1 The subsurface heat dropped to -0.99 in January from -0.94 in December. But the peak was still -1.11 in October for this event. 2007-08 had an Oct-Nov peak and then a second, stronger peak in January at the subsurface. This event had a weaker second peak. The best blend I could come up with was 1995-96, 2005-06, 2007-08 for Nov-Jan. You get slight subsurface weakening in December followed by slight strengthening in January. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt I haven't finished writing it up yet, but my outlook for Spring is probably going to be based on a blend of 1954-55, 2007-08, 2011-12, as an SST/US Weather/solar match with 1978-79 thrown in to account for a very +NAO in November transitioning to a -NAO Dec/Jan. That NAO behavior is very unusual in a La Nina. The blend of the four years, 1955, 1979, 2008, 2012, looks like a colder version of what the Canadian shows for February. The near-record +NAO November correlations should have input on how the Spring evolves. One effect of a very +NAO in November is NM/TX tend to be cold/wet late Spring at a pretty high correlation.

The new Canadian trended the La Nina weaker/warmer for February-April. It does have a brief return to neutral conditions in Summer before another La Nina develops next Fall.

The Canadian forecast for February finally has the Northern Plains getting cold. Interior West & Midwest cold too. Here is how my winter analogs did for January 2021. As with December, the observations snapped closer to the analog blend with time. From the 21st to the 31st, Florida, southern Maine, southern Kansas, West Texas, eastern New Mexico, SE Colorado, southern Arizona, Las Vegas all corrected toward the blend. Green Bay, Des Moines and Kansas City were within 0-3 briefly, on 1/28, and then snapped back to 3-4 out. A lot of the West snapped closer at the end but was too far out at the start of the month.