raindancewx

The UKMet November update is warmer than last month for the winter. Looks like most of their recent November outlooks for winter have been bad for the US though. If that colder look in Western Canada verifies though, someone in the US should at least see impressive cold snaps if nothing else. The look is pretty dry along the Mexican border, but it would only be slightly dry where I am, which is more or less what my analogs had too. I would say the SE tended meaningfully drier on the new run in addition to the warmer look overall for the US. On their probabilistic outlook, Texas is most favored to be drier than average, with the NW & Ohio Valley most likely wet. Only California to Montana has a better than 20% shot of being colder than average on the new run, a smaller area than before.

With the ACE index over 160 now, the La Nina composite favors essentially the entire continental US above average for temperatures. That said, I don't think it should be compared directly, since a lot of storms this year never would have been named or correctly observed at a higher intensity like this year. So I'm treating the current reading like it is still about 150 by historical standards, which is still somewhat cooler in the Northwest. The ACE index is high enough now that places like NYC and Philly have a decent shot a snowy winter - you really can't get a snowy winter in those spots in a La Nina if the ACE is below 150. Even so, the odds are not great. The ten highest ACE La Ninas are 50/50 for above average snow in NYC, but the correlation is pretty direct, and those ten winters average ~200 ACE which is highly unlikely even with two tropical storms out there right now. I have an experimental regression for La Ninas winter highs here. Even at 160 or 170 ACE (favoring a hot SW in a La Nina), it favors a fairly cold winter here because we hit 90 degrees so early, which is where all the cold La Ninas are clustered locally. If you try to match on the three inputs, solar, ACE, and when we first hit 90, a blend of 1954 and 2005 is pretty close.

The local NWS likes a blend of 2007-08, 2010-11, 2016-17 for the winter. That blend is actually very wet for the West - that's my main issue with it. http://www.weather.gov/media/abq/Briefings/202021WinterOutlook.pdf

The local weather service likes 2016-17, 2010-11, 2007-08 as analogs for the winter. https://www.weather.gov/media/abq/Briefings/202021WinterOutlook.pdf

I'm on board with what Roger said - there should be a storm that comes through the West like the October system that runs up the coast at some point, but it would be cold enough for most areas to see snow. It does look like he is using 1975-76 as the main year. Would be cool to see that Spring, pretty sure it snowed down to El Paso last week of April 1976. That was my issue with 1975-76 when I looked - I don't know that we'll transition into an El Nino next year. I don't have a good feel on that at all. The MJO in 1975 isn't terrible compared to this year, but its off by 2-3 weeks timing wise I'd say heading into December. That's one of the reasons I didn't give 2007 full weight in my outlook, it's been off for the MJO timing for a while now. The little heat core max over Nebraska and Missouri is very 1975-76, it's usually warmest in a La Nina in Texas, the Southwest or the Southeast, so it's likely that is the year used at least in part. December is probably the easiest to see as 1975, he's got Florida/New England near average with the heat in Montana like here - The winter of 1975-76 actually did have one very cold period nationally though. With the north Pacific and north Atlantic warmer than in 1975-76, I'd imagine this period would be pretty snowy in some places with more moisture available. I think 1975-76 is probably the right idea (though I don't buy the core of the heat over NE/MO), but with the MJO different I'd expect at least a somewhat different progression. You can see for instance October 1975 was pretty warm in the middle of the country, while it was pretty cold this year. October finished looking a lot like 1954 or even 1959 if you try to find a one year match, and those years do get pretty cold out here like Roger said.

SOI is still erratic - Date Tahiti (hPa) Darwin (hPa) Daily Contribution 30 day Av. SOI 90 day Av. SOI 9 Nov 2020 1012.67 1009.40 2.48 2.57 7.60 8 Nov 2020 1014.23 1009.25 13.36 2.96 7.67 7 Nov 2020 1014.72 1010.80 6.61 3.17 7.67 6 Nov 2020 1013.29 1011.15 -4.71 3.41 7.70 5 Nov 2020 1013.57 1011.60 -5.79 4.04 7.84 4 Nov 2020 1015.26 1011.85 3.37 4.66 8.16 3 Nov 2020 1016.75 1011.55 14.76 4.88 8.41 2 Nov 2020 1017.05 1010.50 23.35 4.62 8.39 1 Nov 2020 1016.75 1009.35 28.76 4.19 8.16 NOAA PDO went a bit more neutral in October. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 30SEP2020 20.1-0.5 23.8-1.1 25.6-1.1 27.9-0.7 07OCT2020 19.5-1.2 23.4-1.5 25.5-1.2 27.8-0.8 14OCT2020 19.6-1.2 23.6-1.3 25.3-1.4 27.8-0.9 21OCT2020 19.9-1.1 23.8-1.2 25.3-1.4 27.8-0.8 28OCT2020 20.0-1.1 23.5-1.5 24.9-1.7 27.9-0.7 04NOV2020 20.3-1.0 23.6-1.3 25.1-1.5 27.8-0.8 Bit of a warm up in all zones this week outside Nino 4. Still prefer 2007 to 2010 because of Nino 4. A blend of 2007/2011 is pretty close for this week as is 1995/2007 08NOV1995 20.6-0.8 23.9-1.1 25.8-0.9 28.1-0.5 07NOV2007 19.3-2.1 23.0-2.0 25.0-1.6 27.5-1.1 03NOV2010 19.7-1.6 23.4-1.6 25.2-1.4 27.0-1.6 02NOV2011 20.5-0.8 23.9-1.1 25.6-1.0 27.9-0.8

Love those big SOI crashes! Check out 11/3-11/5 and the corresponding Western snow 11/13-11/15. Snow anomalies from my winter outlook are very much on target. Don't think California is actually in for a particularly dry winter, but we'll see how that goes. Don't think it is super wet though either.

This is what I get for closest match August-October in each Nino zone, with Nino 1.2 weighted least (x1), and Nino 3.4 (x3) most. Nino 3 and Nino 4 are in between at x2. The unweighted blend is a bit different. 1952, 1959,1961, 1962,1966, 1978,1985, 1995,2007, 2011 For October alone, the top years are very different using the weighting above - Year Oct Oct Oct Oct Match 2020 20.24 23.85 25.48 27.97 0.00 2011 20.24 23.92 25.67 27.86 0.93 1999 20.15 23.60 25.48 27.79 0.95 1961 19.97 23.69 25.71 27.83 1.56 1970 19.88 23.71 25.60 27.59 1.76 2007 19.50 23.55 25.32 27.91 1.94 1956 19.82 23.91 25.75 27.64 2.01 The October blend looks what I had for winter.

Really hope we all get a lot of storms and snow through Feb/Mar. The semi-regular storms for just about the entire West since late October is a good development to counter all the smokiness, heat, dryness and fires. No rain here yet with the storm today. Albuquerque had a high of ~67 in my winter analogs 11/1-11/7, and so far we're at ~70, so it's been a decent match so far. My forecast had a high of ~60 for November locally, so still a long way to go - the cold CPC depicts in the next 10 days or so needs to verify for my forecast to be close. The SOI hasn't really connected with the impressive cold in the La Nina zones, so I'm thinking the warm North Pacific is counter-acting the usual strong La Nina effects to some degree. The cold ENSO years with a +0 to +8 SOI in October (below) tend to be pretty average to cold in the West overall. October 2020 SOI was +4. Only exception is 1933 which is not a great match to this year. A lot of these years are actually extremely hot or dry in the West in Summer-Fall before the flip cold, particularly 1954, 2007, 2012 and 1934. 1954 is probably the best match to October 2020 in the past 100 years nationally, with late hurricane activity, low sea ice for the time, a warm Atlantic, low solar, and a near identical temperature pattern for the US. It's also extremely cold in the SW in the winter - still have trouble buying that, even though I still fully expect some kind of cold-west pattern. We seem to be transitioning to that slowly this Fall, the near to record heat is at least being fought off more regularly than it was in May to September.

Bit more snow for NM today and Sunday. Nothing but rain for the city. I went with 0.05-0.35" for Albuquerque. 1988 has been showing up a lot in the 6-10 and 8-14 CPC analogs. Fingers crossed. If we aren't in a two year La Nina (and I don't think we are), I could see 1989 taking over as the best analog next year.

The cold-ENSO winters following two El Ninos usually do not lead to multiple-La Ninas in a row. I lean toward a Neutral that flashes cold and warm at times for next year but it is pretty early for that. My guess is Nino 4 will be pretty cold early next year, but warming steadily. The other zones will probably warm initially, but might reverse cooler later on. The models have Neutral to near-El Nino conditions by late next year. The transitions after two El Ninos that went to a La Nina/near La Nina are these: 1929-30, 1930-31 --> two cold Neutrals for 1931-32, 1932-33 1957-58, 1958-59 --> two neutrals in 1959-60, 1960-61 1968-69, 1969-70 --> two La Ninas in 1970-71 and 1971-72 1976-77, 1977-78 --> two neutrals in 1978-79 and 1979-80 1986-87, 1987-88 --> a big La Nina in 1988-89, and then a neutral in 1989-90 2014-15, 2015-16 --> I consider 2016-17 a La Nina, but it is really a Neutral strictly speaking, and 2017-18 was a La Nina

The CFS look for next Summer is actually very similar in the Pacific to what the "cold ENSO" after two El Nino look is historically. Those are 1929-30, 1930-31 El Ninos followed by 1931-32 (Summer 1932), and then more recently Summer 1960, 1971, 1979, 1989, 2017. Idea is Nino 4 is still pretty cool, and it occasionally bleeds into Nino 3.4

Weatherbell stuck to their warmed up blend of 1973-74, 1988-89, 2010-10 (x2). The Joe D'aleo Pioneer Model has a lot of years I like as analogs: https://www.weatherbell.com/winter-2020-update I've seen a lot of people saying you can't really get a strong or moderate La Nina look with the North Pacific so warm. You really can if you blend in a year with a very strong La Nina with a year that had a very warm North Pacific. I think blending in 2019-20, 2012-13 in at a low weight with a strong La Nina does a pretty good job warming up the north Pacific a lot without diminishing La Nina strength too much. That's what I did in my outlook anyway. I didn't use all of these years in my outlook, but at this point I think the 10 best analogs for winter are probably 1954, 1961, 1973, 1988, 1995, 2003, 2007, 2012, 2016, 2019. This will be a good year for seeing which factors matters most. My general sense is the warm North Pacific, with low sea ice and a pretty strong La Nina means you'll get (sporadic) very strong troughs/cold dumps into the West, but because a lot of extra moisture sources exist (Arctic Ocean, East Pacific at mid-latitudes), you'll see more snow and wetter Western storms. In the Southwest, we're usually dry in La Ninas because storms run out of moisture by the time they get here if the storm track has to crash over mountains, through cold water and a ridge. I don't think that's the case this year. You had an almost identical SOI crash that preceded the late October snow storm here to 2007, but the system this year had far more moisture. To me, that's likely to keep happening with a warmer North Pacific / Arctic.

The years in the CPC 6-10 and 8-14 day analogs have been changing a lot lately. We're close enough to Dec-Feb now that I think you have to expect some of the commonly repeating years to show up in winter too. For the 6-10: 1958, 1961, 1968, 1973, 1975, 1988, 1989, 1990, 1994. I like 1988 and 1961 as second tier analogs - 1961/2010/2016 is a good QBO/ENSO blend. For the 8-14: 1958, 1973, 1988, 1994, 1996, 1998, 2001 2005 As much as I like 2007-08, it's a double La Nina. The models don't have that. So once we get past Dec/Jan, 1988-89 may actually be the right idea, if we're going to see a lot of weakening out a La Nina, assuming the cold does dump West like I think it will. 1973 is kind of interesting too, since 1974 was a La Nina but far weaker than 1973. I prefer 1988 over 1973 though, since it followed two El Ninos which is quite rare.

This is pretty close to my thought process, although I dislike half of his years. https://www.youtube.com/watch?v=MXg0srzblgk&ab_channel=EricWilhelm He likes 2016-17 as the main analog. I think a de-amplified 2016-17 is sort of the right idea (less extreme warmth East, less extreme wetness West). He mentions a pretty high likelihood of a top five warmest ever winter for his area (Youngstown OH). His blend is: 2016-17 (x4) 2010-11 (x2) 2007-08 1998-99 (x2) 1995-96 1988-89 1983-84 If you were to just do a QBO/ENSO blend, at this point I'd say a 2010/2016 blend is appropriate, and maybe you throw in 1961 to get some more Gulf Hurricane activity in there like this year. That's a 2C SST drop off in Nino 3.4 overall as a blend, which is at least ballpark for this year (I still think its 27.1C to 25.5C for the actual winter, but could be colder). The blend below looks like what I have, but colder in the East/Southeast. Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct 1961 -5.47 -0.62 0.54 2.82 6.88 7.96 6.69 5.60 6.02 7.59 2010 -16.02 -16.98 -19.68 -23.57 -26.28 -25.05 -9.84 1.45 6.58 10.83 2016 9.34 6.77 3.16 0.64 2.37 3.86 6.25 10.07 10.48 12.83 Blend -4.05 -3.61 -5.33 -6.70 -5.68 -4.41 1.03 5.71 7.69 10.42 2020 -2.51 -3.20 -4.36 -5.03 -4.86 -2.78 0.34 4.78 7.95 10.80

The latest plume from the European still has rapid weakening of the La Nina late winter. The cool down is supposed to continue longest in Nino 4 with the reversal (warming) starting slowest there. I think there is a pretty cold period in Nov-Dec for Nino 3.4 (now) before rapid weakening sets in, so i drew in my expectations - aggressive cooling early, aggressive warming late for Nino 3.4. In Nino 4, I like slower cooling initially, and then slower warming late. Those seem to be the biases for the plume in La Nina years from my recollection. The biggest ever (1950-2019) drop off from September to DJF in Nino 3.4 is about 1.0C. So anything below 24.9C (-1.6C) for DJF just strikes me as very unlikely (<2% odds?).

Year DJF JFM FMA MAM AMJ MJJ JJA JAS ASO SON OND NDJ 2020 0.5 0.6 0.5 0.3 0.0 -0.2 -0.4 -0.6 -0.9 CPC lowered the September Nino 3.4 reading to 25.88C fro 25.96C initially. October was 25.48C - warmer than 2007 (25.32C) but still tracking close to it. Nino 4 came in at 27.97C in October - still pretty near the 1951-2010 average. But similar to October 2007 (27.91C). The reading in Nino 4 in October 2010 was already down to 27.15C. So the pattern is a lot closer in Nino 4 to October 2016 (28.32C) still than 2010 despite how cold Nino 3.4 is.

The only November category five in the Atlantic according to Phil Klotzbach (CSU) is the Cuba hurricane of 1932. So I think you'll see some hesitation by NHC to call Eta a five before landfall unless they are absolutely certain. It is interesting looking back, a lot of the strongest La Ninas have had fives - 2007 (Dean), 1988 (Gilbert), 1998 (Mitch), and so on. It did snow in October 1932 in the valleys of the SW, so the pattern that year is likely similar in an MJO sense. The record cold at times this Fall in the West is also similar to some of the great cold waves of the 1932-33 winter (-66 in Wyoming...seems unreal, but Montana set a record low for the continental US in October).

It may not be. But I think older years would have had 10-20 extra points the way storms are tracked and observed today. So I think the final number today minus 10 is a better estimate when compared to historical seasons. I gave a range of 95-175 for the season in my winter forecast for a reason. I fully expected 135, but there are some La Ninas with a lot of late activity.

Mitch killed 10,000 people in 1998 with 180 mph sustained winds at its peak if my memory is right. Similar path and time of year to this. Pretty sure the models didn't get the path right on Mitch - have to watch for that in the coming days.

Hurricane Eta reminds me of Mitch in 1998. Mitch was a god damned beast, especially for late Oct/early November. I sincerely hope this doesn't kill 10,000 people in five days with 75 inches of rain in the mountains and hills of Central America, before ejecting out and smacking Florida like Mitch did. Mitch peaked at 180 mph sustained winds, so I don't think we'll see that. Pretty sure it also stalled forever and did not behave according to model tracks. That's what I remember from back then. Eta does push the ACE into the 150s though. That's likely inflated compared to historical years with systems like the storm that hit Portugal that would have never been named in prior years. But anyway, this is the composite for ~about 150 ACE in a La Nina. Not too different from the 80-160 composite overall.

There is a real chance that Nino 3.4 will be top ten for cold readings since 1950 in both November & December. Especially if the European continues to underestimate how cold it is in Nino 3.4. Anything under 25.4C in Nino 3.4 in November would be top ten for 1950-2019. From there, only a small drop to 25.25C or so would be top ten in December. I do expect substantial warming to begin mid-January. You can sort of see the origins of it with Nino 1.2 and Nino 3 flatlining/warming slowly. The cold-ENSO years with a +0 to +8 SOI in October are also a pretty interesting bunch (+4 in Oct 2020): 1931 4.3 1933 4.1 1934 4.7 1948 6.6 1949 6.0 1954 2.2 1959 4.7 1961 4.7 1983 4.7 1996 5.2 2007 6.1 2012 2.3 It's pretty unusual to have an SOI value at +4 in a pretty healthy La Nina, but 2007 did. This group of years is primarily average to very cold in the West (1931, 1934, 1948, 1949, 1954, 1959, 1961, 1983, 1996, 2007, 2012) or 1933, with much more varied results in the East.

Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 30SEP2020 20.1-0.5 23.8-1.1 25.6-1.1 27.9-0.7 07OCT2020 19.5-1.2 23.4-1.5 25.5-1.2 27.8-0.8 14OCT2020 19.6-1.2 23.6-1.3 25.3-1.4 27.8-0.9 21OCT2020 19.9-1.1 23.8-1.2 25.3-1.4 27.8-0.8 28OCT2020 20.0-1.1 23.5-1.5 24.9-1.7 27.9-0.7 Nino 4 and 1.2 warmed a bit this week. Big drop in Nino 3 and 3.4 though. The current La Nina is now stronger/colder in Nino 3.4 than 2007 at this point, but warmer elsewhere. I was expecting Nino 3.4 to come in around 25.55C since the monthly data usually runs above the weekly data, but it looks lower than that now. This week the data is about half way between 1995 and 2007 in the eastern zones, but now much stronger/colder than 1995 in Nino 3.4. The slow cooling in Nino 4 is a feature of both years. Nino 4 was already dropping below 27.0C in 2010 and a lot of older La Ninas by this point (November). 31OCT2007 19.7-1.5 23.2-1.8 25.2-1.5 27.8-0.8 25OCT1995 20.3-0.7 24.0-0.9 25.6-1.1 27.9-0.8 Pretty healthy La Nina in Nino 3.4 though - will likely be in "strong" territory in Nov-Dec before weakening.

Cold ENSOs with ongoing MJO waves around phase 7 on 11/1: 2017 - started but died, i.e. lower magnitude 2016 - a week late for phase 7 2000 - pretty close to the Euro outlook by timing intensity (phase 2 by 11/15 like in 2000) 1996 - 10 days late for phase 7, and higher magnitude That's really it since 1975. As a blend, it's pretty close to what the Canadian showed for November. My unweighted winter analog blend was pretty close in October, and looks like the models for November. But of course, there is a much simpler blend to get Oct-Nov...1954:

His analogs do have some interesting features though. He's got warm periods in there for almost everyone - often near record warmth. Think December 2014 for the NE, or 1995/2005 for the SW. But then he has incredible cold periods like Jan-Mar 2014 and 2015 for the Midwest and NE. The mid-Dec to mid-Jan period in 1978-79 is super cold nationally, and as I've showed previously in here, Jan 3-9 1971 is insanely cold in the West, 20 below average in New Mexico and Colorado, for a week, despite that month warming up a lot later. The 1995 and 2009 winters are also pretty cold/snowy for a lot of the US. But 2005 is not. So I think he is trying to get at how volatile the winter could be. Where I am he has December 1959 with two feet of snow in the valleys, and February 2015 with 10 inches of snow in the valleys. The mountains saw 50-100 inches in those periods in a week or so, and that does tend to happen every five years or so. The 1959-60 period also has a major thaw in the middle of the country in the mid-Dec to mid-Jan period.