raindancewx

I keep seeing people referencing 2013 as an analog because of the blob, but the pattern nationally really is closer in the East so far to 2018 than to 2013, which to me implies it isn't much of a factor due to differences in the PDO structure. That light blue area should end up very close to Mexico by the end of October 2019, but the issue with both years is they were too cold in the SW and too warm in the NW. Nino 3.4 readings will be similar in October 2014 and 2019, but the US pattern is completely different. The strongest response for US temps to winter from the PDO are in the NW US and SE US. So the very cold NW / very warm SE October has some resemblance to a -PDO for Winter 2019-20, while the very warm NW / relatively cold SE in 2014 has some resemblance to what would become the super positive PDO winter of 2014-15, when the PDO was +2.07 for Nov-Apr (sort of the PDO equivalent of a Super El Nino). The October 2014 'cold' spot is right where the deep purples are for the winter correlation.

January 1952 is like +7F in the SE, with December/February not much better. I don't think 1951-52 will hold up real well outside Fall though. Nino 4 is much warmer than in 1951, and like you said, the PDO crashed hard to well below 0 by December 1951, which is correlated to strong winter heat for the South. In Fall/Spring, I generally weight the PDO/AMO higher, with the prior year ONI, solar, and some other things less. As solar/ONI prior and the others become more important, 1951 should fall of as a match. I looked earlier - the best October matches to this October in an El Nino since 1930 are: 1939, 1941, 1951, 1969, 1994. Something like 2014 is relatively opposite, with places in the Northwest out by close to 20 degrees compared to what has happened this October, despite similar Nino 3.4 temps.

The warmth is still moving East. Really not that different from last year. Main difference is there is more cold water around this year.

October 1951 is honestly shockingly close to October 2019 for temperatures nationally - one of the best single year analog matches I've seen in a few years. Oct 1951 was a 27.2C El Nino in Nino 3.4, but it was an East-based El Nino by this point. In the West, the cold should actually push further South than 1951 by the end of the month. Areas near the Mexican border in New Mexico will be 25-30F outside the cities tomorrow morning - very cold for October that far south at fairly low elevations.

Snow in Santa Fe...low 50s in Albuquerque today. Amazing how sharp the cut offs can be in Fall and Spring systems that don't quite dive far enough south.

Last year behaved like Neutral PDO El Nino, which dumps cold in the West and Plains typically. I use 0, +/-0.5 for Nov-Apr, for the PDO as that designation. The composite is basically the same post 1950 (kind of looks like this October which is interesting). Box C (the waters by the Philippines) in the Modoki calculation is fairly strongly correlated to colder Western winters, and that zone has been relatively cold compared to recent years. Low solar El Ninos also tend to be less reliably "back-loaded" for the East in February - look at February 1931, 1954, 1964, 1966, 1977, 1987, 1995, 2007, 2010, 2019 - definitely a variety there compared to the high solar El Nino February years. Our high terrain never stopped being cold this year, a lot of the populated towns still had frosts in June, July and August. At this point, things look at least somewhat promising for the West. Here are some pictures from New Mexico today - Angel Fire Ski Resort Red River -

My analogs had some incredible cold pushes in the West and Plains in November, despite relatively bland departures overall. A big -NAO is correlated to a warm West in November generally but you can get big snow events in the Rockies despite an overall warm November. Conceptually, the "anti-logs" to the features this year, a cold Atlantic, cold North Pacific, weak La Nina, after a weak La Nina, both in high solar, with an active Monsoon in the SW ahead of winter...is something like 1967 or 1971. If you look at October 2019 and then October 1967 and October 1971, they are both opposite of 2019 in their own way. In 1967, the core heat/cold is East/West backwards v. 2019 in October, even though it is roughly at the right latitudes. Winter 1967-68 "flipped" for being east-west backwards actually looks fairly close to what I forecast for winter. In 1971, the cold core is in the SW, and the heat core is in the NE. In 2019, the cold core is in the NW, and the heat core is in the SE. So it is North/South opposite. Winter 1971-72 flipped "North-South backwards" actually also looks fairly close to what I forecast for winter.

I couldn't get it to work at my office either. It is a link to Scribd, so maybe it is blocked? I think some have been able to see it. It is free. But I may do some subscription stuff at some point. I have a big collection of strong predictors for each region of the US now, and I've done statistical work on how they should be weighted for different seasons, and to account for the Earth warming somewhat, as well as solar stuff. For instance, in the Southwest, solar activity is a meaningful precipitation variable for Spring/Fall, but not really for winter. But in winter it does correlate for temperatures, when filtered by ENSO, and it gets stronger at certain elevations for whatever reason. https://www.scribd.com/document/429712619/Winter-2019-20-Outlook I want to be clear here: There are some El Ninos when I would go huge for snowfall in New England and the Northeast generally. I don't mean 20-50% above average, I mean double average generally, up to x3 or x4 locally - but they're rare. The blend you want is high solar, El Nino, but El Nino Modoki. 2014, 2002, 1991, 1977, 1969, 1968, 1957 all fit some extent. For what it's worth...1951-52 is an El Nino and remarkably close to October 2019 so far. It's kind of a weird borderline El Nino like this will be, which is interesting. I didn't use it as analog though. 1994 is actually pretty close in the West, and 2018 isn't too dissimilar either in October, its just the heat/cold are nudged out of place compared to 2019. Some of the El Ninos in the 1930s and 1940s aren't terrible matches to 2019 either for what its worth. If you're in the East, you do not want the 1951-52 winter if you like snow and cold.

Good start after a quiet October in New Mexico outside of one major rain event in SE NM very early in the month.

2004 is probably a good analog to November. If I had done Fall analogs, 1994, 2004, 2012, 2017, 2018 as a blend would have been pretty good. But I don't really see it lasting into winter. All the components are there - MJO matches 1994, 2004, 2018. The cool east is there with 2017 included. The temperature profile in the US looks like where Oct 2019 is going. The PDO is neutral. The IOD is positive. The coolness east of South America is there, with the gulf stream very warm off the East Coast. It's relatively low solar too. 2014 doesn't exactly look like 2019 in October...despite somewhat similar MJO progression...it makes sense since 2014 was a basin-wide El Nino in October. Only off by 10 or 20 degrees in the NW...but you know New England is destined to see snowmaggedon again. 2004 isn't as different in October as 2019, but it's still kind of north/south backwards, just a 2014 v. 2019 is east/west backwards.

Bye bye Modoki? Nino 1.2 has warmed up above 20.0C - so the PDO likely will remain positive, at least slightly for Nov-Apr. El Nino development is around a month slower than last year so far. But October Nino 3.4 reading is up to about 27.3C now. That's El Nino level, even using the 26.75C CPC uses for October as Neutral. Subsurface warmth is up again too. It looks like the subsurface heat for 100-180W could be around +0.6 or +0.7 - that is similar to October 2004 & October 2014. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 25SEP2019 20.0-0.5 24.8-0.1 27.2 0.5 29.7 1.1 02OCT2019 20.0-0.6 25.1 0.3 27.2 0.5 29.7 1.0 09OCT2019 19.7-1.0 24.8-0.1 27.1 0.4 29.5 0.9 16OCT2019 20.6-0.2 25.3 0.4 27.5 0.8 29.7 1.1 26SEP2018 20.2-0.3 25.5 0.6 27.3 0.6 29.3 0.6 03OCT2018 21.3 0.7 25.6 0.7 27.4 0.7 29.5 0.8 10OCT2018 21.1 0.4 25.6 0.7 27.3 0.6 29.5 0.9 17OCT2018 21.1 0.3 25.9 1.0 27.6 0.9 29.6 0.9

There is a fairly strong signal in the years I like for a big snow storm around Nov 20 for New Mexico, likely parts of Colorado too. The pattern in ocean temperatures kind of looks like 2004 which I believe had some big storms in November. if I had done fall analogs, 2004 would have made the cut, I just don't like it for winter. 2012 is actually pretty good for Fall too. November might be something like a blend of 1994, 2004, 2012, 2017, 2018 and then the 2012/2017 will vanish from relevancy for winter from rapid cooling. 1994/2018 will likely fall off too once the MJO match in October wanes a bit. The blend matches reality fairly well for temps - cold West/warm East (and the warmth by end of Oct will be a lot less than now even int he SE like in the blend), and then the West is fairly warm in Nov, with average or slightly wetter than average precipitation. The blend respects the warm Atlantic, positive IOD, warm tongue east of Japan relative to cooler waters by NA to some degree, with extensive cold on both sides of South America. We'll see.

It's not exact, but in some ways we're about a month behind the development of the El Nino last year. The cold by South America was mostly defeated by this point last year. But...it was still there in September 2018. The Oct 2019 pattern by South America looks a bit like the blend of Sept/Oct 2018.

This is what I had for snow nationally in my winter outlook - but I think for Colorado after a quick start there is something of a break until late winter. My snow map was fairly good last year. Montana and Virginia did better than I thought, and I should have had an elevation component for the West last year since the valleys in NM were much closer to average than the mountaintops everywhere.

Large area of +1C to +2C heat has filled into Nino 3.4 during the last month. With the surface readings over 27.0C in October...that's enough for Nino 3.4 to stay warm for a while. The cold in Nino 3 (90W-150W) is just about gone now too, although Nino 1.2 is still going to take a while to warm (maybe til December).

Pretty sure the IOD was positive last year too by Fall anyway, although not as much as this year. The Jamstec has it falling off later. The main thing with the IOD is it is a way to keep relatively high pressure over Australia, which helps the SOI stay negative or neutral.

The (relatively) cold backwards C by the Alaskan Coast around that blotch of warmth is a pretty canonical -PDO, especially with the warm waters east of Japan. 2014 was the opposite - super warm by the coast of Alaska, and cold east of Japan. Will the -PDO ish look now last all winter? I kind of doubt it. Just because Nino 1.2 falling below 20.0C in October is a leading indicator that the PDO will fall. It did on the weeklies. But now it looks like it will warm up. So it probably reverses, at least somewhat, by December or January. Even with the El Nino last year, the Nov-Apr PDO only recovered to +0.5 from +0.3 in 2017-18. With a weaker El Nino this year, it could easily be closer to 0. The trend has been down. I think the PDO is weak enough that the SE ridge won't get squashed or destroyed for any length of time, and when the subtropical jet is strong, and the SE ridge is strong, that is the best shot at major storms (cut offs) for where I am, as the two battle it out. Nov-Apr PDO 2013 0.38 2014 2.07 2015 1.70 2016 1.06 2017 0.30 2018 0.51 With the NAO negative, the winter -PDO correlations seem to work about perfectly for October so far.

Nate Mantua PDO value came in today: https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_OC_PDO.htmlTable?time,PDO Sept 2019: +0.41 Aug 2019: +0.38 Sept 2018: +0.09 I believe October will be substantially lower than September, but we will see.

I used different analogs, but I agree on the mid-winter warm up for the East. The years I picked had the NAO negative in December, neutral in January, then positive February. More generally, the big warm Sept-Oct periods in the East usually feature some kind of late warm up in winter it seems like. My pure analogs are actually very cold in December, but I think it will be warmer (somewhat) in the East with Nino 4 near record warmth than the raw blend. I also agree on a pattern with some huge storms - I think there are somewhere between 3-5 historic storms Nov-Mar nationally, it's just where? Dorian, the recent record blizzard in the NW a few weeks ago, and the relatively rapid shifts in temperature profiles in the Fall all hint at it. I think the culprit for the cold shifting positions is likely the changes in the PDO. It appears to be heading negative, with the cold ring next to Alaska developing around a warm tongue east of Japan right now. The Modoki El Nino look right now is also likely to break down, which favors the West later, as you say.

Not quite as warm as last year....but pretty close now in Nino 3.4. I think the Jamstec is too cold in the SE, but I'm broadly on board with what it has. A Modoki El Nino (ish) with a neutral or -PDO (colder right by Alaska for SSTs, with a warmer tongue east of Japan. I really struggle with places in the mid-south going from +8 to +12 in October, after a warm September, to a very cold winter like the model shows. The Jamstec is a bit drier than I am in the Rockies (I think we're near to slightly above average, it has near- to below).

Just for reference: Nino 3.4 is now very close to last year. K - 273.15 = C for reference. So the 27.0C is orange, because it is 0.5C or more above the 1951-2010 October average in Nino 3.4

At the end of the day, you can try to forecast a season using two basic methods: 1) Find predictive variables and guess what they will do (this seems to be what most of you do). That will work most of the day, but you'll get situations like last year, where 1963 matches on most of the variables that are predictive but end up completely different by ignoring weather clues, like the super hot October 1963 compared to the very cold October 2018. My analog system, prior to incorporating weather matches had 1963 as a top three match last year...but it fell off to like 15th with weather included in Fall. (2018-19 was 27.40C in Nino 3.4 for DJF, 1963-64 was 27.35C in Nino 3.4 for DJF) 2) Find predictive variables. With the predictive variables find a blend that matches the weather for a long-period, with the variables and weather still heading in the "correct" direction together going forward. This is what I try to do. I'm really looking forward to seeing the forecasts this winter - there are so many more things that can go wrong this winter compared to last winter: 1) Solar - there is a non-negligible chance of a rapid increase by mid-2020 2) PDO - it looks like it is heading more Neutral, and maybe legitimately negative, but it also may snap positive. My analogs assumed near neutral, on either side. People see the Blob and think "2013" but US weather really hasn't matched well to 2013 at all since Summer. October has been a bit closer, but I think it is a case of two trains passing each other from opposite directions. In 2013-14, the PDO was warming from years of being in the predominantly negative phase. In 2019-20, it is cooling from years of being in the predominantly positive phase. 3) ENSO structure. Modoki El Nino since September. But Nino 1.2 is losing the cold pool below it, Nino 4 warm pool below it is moving east. 4) NAO. Pretty rare historically to have any streaks <=-0.3 more than four months, less than 2% of all possible outcomes. October is negative. November probably will be too. 5) SOI under -10 in September is like a ~95% El Nino indicator for winter. For what its worth, the new Jamstec (October) does have an El Nino Modoki look continuing in winter, with a cold East. The dry slot from TX to MI, with New England and the West Coast warm is pretty much what I had in my forecast.

Nino 1.2 is currently under 20.0C in October on the weeklies. The monthlies usually come in warmer for Nino 1.2...still, if the month finishes under 20.0C in Nino 1.2, a -PDO is likely for winter. Since 1950, 17/18 years with a <20.0C Nino 1.2 in October have finished with a -PDO for Nov-Apr. With an El Nino forming, that can be an incredible pattern nationally. The temperature pattern for October (super cold NW / super hot SE) is consistent with the PDO correlations to winter when the PDO is negative. This is the composite for when the PDO finishes under 0 for the Nov-Apr period, in an El Nino (it is the same idea - cold West / mild East if you use only 1950+ years)

All fear the PDO? The JISAO update isn't in for September yet, but the severe cold in the NW and severe warmth in the SE are both showing up in the zones that correlate highest to the PDO for winter. The cold ring by Alaska hasn't been there in a long time but it is trying to form.

The cold pool near Peru is starting to surface so Nino 1.2 and Nino 3 cooled this week. Nino 3.4/4 were down a tiny bit. Against 1951-2010 averages in Nino 3.4, 27.0C is +0.5C, but CPC uses 26.75C, the 1985-2014 average, for Nino 3.4. Either way, Nino 3.4 for October is at borderline El Nino conditions - 27.15C or so, pending the rest of October...but lots of warmth below the surface is set to come up shortly. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 18SEP2019 19.1-1.3 24.2-0.6 26.5-0.2 29.3 0.6 25SEP2019 20.0-0.5 24.8-0.1 27.2 0.5 29.7 1.1 02OCT2019 20.0-0.6 25.1 0.3 27.2 0.5 29.7 1.0 09OCT2019 19.7-1.0 24.8-0.1 27.1 0.4 29.5 0.9 You can see that if we pop up to 27.15C or so in October, it's fairly close to the top 10 warmest Octobers already (27.58C is 10th since 1950). Nino 3.4 for the past three weeks has more or less caught up to 2014-15 at this point, but 2014-15 was much warmer in Nino 3/1.2 and colder in Nino 4. At this time of year, Nino 1.2 tends to lead what the PDO will do - so the very warm Nino 1.2 in 2014 preceded the +2.07 PDO reading for Nov-Apr. 17SEP2014 21.0 0.7 25.2 0.4 27.2 0.5 29.4 0.8 24SEP2014 21.2 0.8 25.4 0.5 27.1 0.4 29.3 0.6 01OCT2014 21.7 1.1 25.4 0.5 27.1 0.3 29.2 0.5 08OCT2014 21.3 0.6 25.5 0.6 27.1 0.4 29.1 0.5