raindancewx

Looking historically, it is fairly rare to get extended -NAO streaks (-0.3 or lower for more than three months). Will be interesting to what happens. August will be month four. If you match up the difference in the monthly NAO for May-Apr and Sept-Mar ahead of a given winter, you can usually get a pretty good sense of what the NAO will do in winter. The May-Apr and Sept-Mar readings last year for the NAO were near identical to 1975-76, a year near the solar minimum that had a positive NAO during winter. Will be interesting to see what September finishes with for the monthly NAO-reading. NAO Sept-Mar May-Apr DJF 1975 2.17 1.08 0.23 2018 2.60 0.88 0.50 I'm assuming the -NAO stays in September, but it comes up toward 0. If that is the case, 2017 and 1994 might be a good blend for the NAO in 2019. I selected these time periods because they have fairly high correlations to winter (each has an r-square near 0.1 individually for 1950-2018), and Sept/Mar represent the highest/lowest points for Atlantic heat, and May is usually a good indicator for how the Spring/Summer will setup in the Atlantic. 1994 -2.58 -1.71 1.36 2017 -1.35 -3.64 1.30 Mean -1.97 -2.68 1.33 2019 -1.80 -3.09 The subsurface is still pretty cold east of 120W, and even in the western part of Nino 3.4, there is a fair amount of cool water below the thin warm patch near the surface.

I was kind of surprised at how close 2004 has been for SSTs globally for the past month. Fairly strong match for local weather here since Spring too. My hunch is the blue area off South America expands, and the deep reds by 180W shrink somewhat. PDO zone will likely fill in red around 180W too, as the waters by Alaska cool a bit, relative to normals.

The August Jamstec has gone back to near-El Nino conditions again for winter, about 0.5C lower than what it forecast last August for 2018-19, when it correctly had the ONI peak around +1.0 (it was +0.9C). Even so, the US is not depicted as particularly cold anywhere. The latest run has the East Coast slightly cold, the rest of the US warm.

https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_OC_PDO.htmlTable?time,PDO PDO is still hanging around +1 on the JISAO methodology - 2019-01-01T00:00:00Z 0.66 2019-02-01T00:00:00Z 0.46 2019-03-01T00:00:00Z 0.37 2019-04-01T00:00:00Z 1.07 2019-05-01T00:00:00Z 1.03 2019-06-01T00:00:00Z 1.09 2019-07-01T00:00:00Z 1.03 I got a response about the Jamstec Modoki data from Toru Miyama. On the link he gives, you can download the data. The Modoki value for the 2018-19 winter was +0.51, below 2009, 1968 and the other most Modoki winters. It was actually around +0.4 in Dec-Jan, but instead of lowering in February as my analogs had, it increased, which is why February went kind of nuts for the Plains (coldest month in Billings since 1936). The year I double weighted for the 2018-19 forecast, 1994-95, did have a Modoki value virtually identical to last winter, so I think the blend I had was pretty decent for the tropical pacific.

I asked one of the Jamstec researchers on Twitter to update the EMI (El Nino Modoki Index) data - it hasn't been updated since November for the monthly data. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 17JUL2019 21.3-0.3 25.6 0.0 27.4 0.2 29.7 0.9 24JUL2019 21.1-0.2 25.5 0.0 27.6 0.4 29.8 1.0 31JUL2019 20.6-0.5 25.2-0.2 27.5 0.5 29.8 1.0 07AUG2019 20.3-0.6 25.3 0.1 27.3 0.4 29.6 0.9 19JUL2017 21.4-0.1 25.7 0.2 27.6 0.4 29.2 0.4 26JUL2017 21.3 0.0 25.5 0.1 27.1 0.0 28.9 0.2 02AUG2017 20.9-0.1 25.4 0.1 27.2 0.2 28.9 0.2 09AUG2017 20.5-0.3 25.1 0.0 26.7-0.2 28.7 0.1 Nino zones still aren't dramatically different in the East from 2017, but the western zones were far colder by this point in 2017. Will be hard for a La Nina to form if Nino 3.4 / 4 stay pretty warm for much longer. I was looking through the DJF data earlier - I think Nino 4 could end up around 28.70C (colder than last year, well above average though), with Nino 1.2 around 24.00C (cooler than average and last year). I wanted to see if that was a record temperature disparity between the two zones during winter. It is not, but it isn't far off from the spread in 1953-54, which is the record, when you had a very cold Nino 1.2 (23.25C) and a warm Nino 4 (28.37C). Nino 4 is a fairly strong wet signal for the West when it is warm. The subsurface stuff has a different scale now? The subsurface almost looks like a "warm-Neutral" Modoki. Will be curious to see what the Jamstec has this month. Pending August, a blend of 1995-96 (x2), 2004-05, 2009-10 (x3), 2010-11, 2013-14, 2016-17, 2018-19 looks somewhat like the ocean pattern I expect for winter, while also matching my monthly Summer highs and monthly Summer precipitation. As a blend, Nino 3.4 would be +0.3C v. 1951-2010 (26.8C), with a warmer Nino 4 and much colder Nino 1.2 and Nino 3. As a blend, it is a weakly positive PDO (which I like if Nino 1.2 stays cold), with a warm Atlantic and low solar. Will continue to revise and test analogs as Summer data comes in. As a blend, those year follow a 26.95C or so Nino 3.4 winter, and 2018-19 was 27.39C.

My hunch is the Nino 1.2 / Nino 3 coolness will keep the PDO from maintaining that big blob of warmth off the coast of Alaska. The NAO is still negative, and should finish August negative. The very warm AMO / cold East warm West tropical Pacific is relatively similar to 2012, but with a few major differences. Big persistent -NAO in these months of 2012 too. A warmed up 2012 in the tropical Pacific, after an El Nino, with lower solar is probably a colder, wetter winter than 2012-13 nationally, but we'll see. I want to see how August plays out locally, not a lot of Summers following an El Nino winter that go cold June before warming up late. Monsoon has been weak/erratic so far, which is atypical with a positive PDO/low solar, but consistent following a wet cold/winter in the Southwest - will be interesting to see how we finish for Summer rains.

Almost all the European plumes have joined the Neutral train. The model had the right idea for the El Nino last August for reference. Nino 1.2 is forecast to remain quite cold for the foreseeable future - with Nino 3 maybe dropping negative, than warming slightly positive. Nino 4 is forecast to remain positive throughout the foreseeable future.

It looks to me like the warm waters 140W-170W are going to remain and get reinforced, while the cold waters 120W and east are also going to get reinforced. Nino 3.4 is 120W-170W. So..Neutral into Fall at least?

In an SOI sense, May (-7.4), June (-10.0), July (-5.9) is pretty similar to recent years like 1992, 1993, 2002, 2006. A low solar El Nino winter after an El Nino would be very difficult to analog with historical years. 2004, 1987, 2015 all had 50-70 sunspots in July-June on an annualized basis. We'll probably be at...10 or so. Or less. 1930 had 40/month after the weak El Nino of 1929-30. SOI May Jun Jul Match 2019 -7.4 -10 -5.9 0 2006 -7.7 -6.7 -8.6 6.3 1946 -10.0 -8.8 -9.5 7.4 1949 -4.8 -10.9 -1.6 7.8 1993 -7.3 -14.4 -10.1 8.7 1992 0.4 -11.9 -6.5 10.3 2002 -13.8 -6.8 -7.1 10.8

Weeklies show more heat decay in Nino 1.2 / 3 Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 03JUL2019 21.8-0.3 26.1 0.2 28.0 0.6 29.7 0.9 10JUL2019 21.7-0.2 25.9 0.1 27.7 0.4 29.7 0.9 17JUL2019 21.3-0.3 25.6 0.0 27.4 0.2 29.7 0.9 24JUL2019 21.1-0.2 25.5 0.0 27.6 0.4 29.8 1.0 31JUL2019 20.6-0.5 25.2-0.2 27.5 0.5 29.8 1.0 05JUL2017 21.7-0.3 26.1 0.2 28.0 0.6 29.4 0.6 12JUL2017 21.8 0.0 26.1 0.4 27.8 0.5 29.3 0.5 19JUL2017 21.4-0.1 25.7 0.2 27.6 0.4 29.2 0.4 26JUL2017 21.3 0.0 25.5 0.1 27.1 0.0 28.9 0.2 02AUG2017 20.9-0.1 25.4 0.1 27.2 0.2 28.9 0.2

Year DJF JFM FMA MAM AMJ MJJ JJA JAS ASO SON OND NDJ 2010 1.5 1.3 0.9 0.4 -0.1 -0.6 -1.0 -1.4 -1.6 -1.7 -1.7 -1.6 2011 -1.4 -1.1 -0.8 -0.6 -0.5 -0.4 -0.5 -0.7 -0.9 -1.1 -1.1 -1.0 2012 -0.8 -0.6 -0.5 -0.4 -0.2 0.1 0.3 0.3 0.3 0.2 0.0 -0.2 2013 -0.4 -0.3 -0.2 -0.2 -0.3 -0.3 -0.4 -0.4 -0.3 -0.2 -0.2 -0.3 2014 -0.4 -0.4 -0.2 0.1 0.3 0.2 0.1 0.0 0.2 0.4 0.6 0.7 2015 0.6 0.6 0.6 0.8 1.0 1.2 1.5 1.8 2.1 2.4 2.5 2.6 2016 2.5 2.2 1.7 1.0 0.5 0.0 -0.3 -0.6 -0.7 -0.7 -0.7 -0.6 2017 -0.3 -0.1 0.1 0.3 0.4 0.4 0.2 -0.1 -0.4 -0.7 -0.9 -1.0 2018 -0.9 -0.8 -0.6 -0.4 -0.1 0.1 0.1 0.2 0.4 0.7 0.9 0.8 2019 0.8 0.8 0.8 0.8 0.6 0.5 +0.44C / 27.70C for July 2019 in Nino 3.4

ONI fell to +0.5C for MJJ. https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php YR MON TOTAL ClimAdjust ANOM 2018 7 27.42 27.26 0.16 2018 8 26.95 26.91 0.04 2018 9 27.19 26.80 0.39 2018 10 27.62 26.75 0.86 2018 11 27.61 26.75 0.86 2018 12 27.49 26.65 0.84 2019 1 27.21 26.45 0.76 2019 2 27.49 26.66 0.82 2019 3 28.11 27.21 0.90 2019 4 28.46 27.73 0.72 2019 5 28.50 27.85 0.65 2019 6 28.19 27.65 0.54 2019 7 27.70 27.26 0.44

If 1969 is going to be a good analog for the winter, there will be some special things that happen in the Summer. I'm not saying Pass Christian has to deal with another Camille, but I've always taken that event to be triggered by a strong MJO wave, probably stuck in phase 1/2 in August given the cold SE / warm Plains & West August look that year which is identical to the MJO composites for August. Given that it looks pretty cold in the areas that were pretty hot in August 1969, I'm inclined to think the MJO timing is off from 1969 if nothing else (No MJO data exists before 1974 though). Sometimes the MJO wavelength changes, so it's hard to say what will happen by Fall/Winter. The six El Ninos with major hurricanes hitting the US all seem to have a common characteristic - slow, but potent MJO progression (1941, 1957, 1965, 1969, 2004, 2018). I don't have a good read on Fall/Winter yet. If the NAO stays negative into Fall, it starts off as a cold signal in the SW in September, but then migrates to becoming a cold signal for the East (especially the SE in November). I don't have a La Nina or El Nino for winter, I think its a cold Nino 3/1.2, with an average Nino 3.4 and a warm Nino 4. The NAO was pretty negative in May-Aug in 2012 and 2016 though, so it may not mean too much for US cold. My hunch is the winter will be generally warm on a day to day basis, but most places in the US will see 2-3 weeks of near record cold, and end up near to below average against long-term highs. We had a cold June here, which is a strong indicator of a cold winter in the last 100 years (12/19 winters since 1931 below average when June high is 2F or more below 1931-2018 average). There is no period since the 1890s to my knowledge where the Northern Plains and Montana had four severely cold winters in a row - so you have to bet against that since they had three from 2016-2018. The South won't be severely cold without a very positive PDO or very -NAO all winter. The PDO currently looks screwed up again, with a lot of warmth in the Gulf of Alaska (+PDO) but also east of Japan (-PDO). So it is on the NAO probably for the NE.

The subsurface data looks like it will shift above the 2017 baseline now. At this point in 2017, warmth in Nino 3.4 was rapidly fading as cold emerged from below the surface. Things look pretty different in at least the western part of Nino 3.4 this year so far. That blob of warmth by 160W is pretty deep now. There is a fair amount of cold to surface east of 120W which will keep Nino 1.2 and Nino 3 cool for a while. I'm on board with very slow cooling through Fall in Nino 3.4.

This is way over done isn't it? Cold everywhere? If you look at the month to month progressive for US temps, there is no variation at all between some months. I think the data got messed up somehow. The August part of the forecast looks fine, then it dramatically goes colder. I think it's probably because the subsurface data isn't loading. Anyway, the subsurface for 100-180W was +0.14 in July. Still fairly similar to 2017. I was playing around with what the CFS was showing on 7/31, and it looked like a blend west based El Ninos and east-based La Ninas / cold Neutrals.

New Canadian Model is in on Tropical Tidbits, but I think something is wrong with the input/output. The site has the entire Northern Hemisphere (save by Alaska) filled with colder than normal waters.

Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 03JUL2019 21.8-0.3 26.1 0.2 28.0 0.6 29.7 0.9 10JUL2019 21.7-0.2 25.9 0.1 27.7 0.4 29.7 0.9 17JUL2019 21.3-0.3 25.6 0.0 27.4 0.2 29.7 0.9 24JUL2019 21.1-0.2 25.5 0.0 27.6 0.4 29.8 1.0 Still hanging on to a lot of warmth West. Nino 3.4 will be around 27.65C in July. That is warmer than the July readings for 2017, which had to fall very sharply to become a La Nina. 05JUL2017 21.7-0.3 26.1 0.2 28.0 0.6 29.4 0.6 12JUL2017 21.8 0.0 26.1 0.4 27.8 0.5 29.3 0.5 19JUL2017 21.4-0.1 25.7 0.2 27.6 0.4 29.2 0.4 26JUL2017 21.3 0.0 25.5 0.1 27.1 0.0 28.9 0.2 July was similar to 2017. To get to a La Nina from a warmer start in July, August will need a sharper drop than in 2017. 02AUG2017 20.9-0.1 25.4 0.1 27.2 0.2 28.9 0.2 09AUG2017 20.5-0.3 25.1 0.0 26.7-0.2 28.7 0.1 16AUG2017 19.9-0.7 24.5-0.5 26.4-0.5 28.8 0.1 23AUG2017 19.6-1.0 24.6-0.4 26.7-0.1 28.9 0.2 30AUG2017 20.3-0.2 24.5-0.4 26.5-0.2 28.8 0.2 If the -NAO continues in August, that is a strong cold signal in Montana, and a strong warm signal for Texas. Nino 3.4 warmth in August (+0.4 or so against the base CPC uses in July) is a wet signal in the Rockies and a cold signal in the Great Lakes/Midwest. I had the middle of the US cold in August using my Summer analog blend from May, 1966, 1966, 1987, 1992, 1993, 2015, with both coasts warmer - that doesn't seem crazy. Going into winter, it looks like the PDO base state will be pretty positive (+1.0 or so) for March-August, but Nino 1.2 may end up colder than average in October. That's fairly unusually historically and has some implications for what the PDO will do. I think the PDO stays positive, but the core of the warmth in the Gulf of Alaska moves.

I'm not a huge fan of 2013 as an analog. People should go look at how hot June 2013 was in the West - and then it got colder. Kind of the opposite this year. I don't consider 2013-14 a La Nina, but it certainly had a month or two that flirted with La Nina territory, and Nino 3/Nino 1.2 were much colder by now in 2013. Also, 2013 had a relatively high min for sea-ice extent in September, which doesn't look like this year.

When I say "harder than last year", I base that off the fact there is no low-solar Neutral year since 1952-53. The closest, arguably are 2016-17, 2012-13, and 2003-04 in the last 20 years, but the 2016-17 had a warm Nino 1.2 which doesn't look likely at the moment, and the others had solar activity. I think you could see a winter with weak and erratic tropical forcing - so then the question becomes what takes over? The PDO is positive but it still kind of screwed up and not likely to get to 2014-15 levels (+2.07 for Nov-Apr) which is strongly correlated with cold in the SE US. I tend to align observed US weather with global oscillations in the tropics to "match" initial conditions. Summer is going as I expected more or less - I thought some Eastern areas of the US would be +3 to +5 in July, after a fairly cold June nationally, and I had the West cold in July (although not where I am - had us warm). May-July -NAO is a weak warm signal in Fall for the West and NE. Will be interesting to see if the MJO cooperates. Last Fall, we had a very warm September and then a very cold Oct-Nov in the SW. But you can see that is unlikely this year, at least in Arizona where the -NAO in MJJ is a big deal for Fall.

I had a relatively low snow totals for the NE coast in my winter forecast last October, based on the premise that nearly all low-solar El Ninos see below average snow from Boston to Philadelphia back to the 1800s. Billings and much of the Northern Plains had one of their all-time cold months in February 2019, which isn't what I forecast, but my blend of 1953, 1976, 1986, 1994, 1994, 2006 was pretty close from about 12/1-1/31, really even through 2/10. The severe cold in the Plains and West lasted too long in February though. Snowfall was heavy in the West, downwind of the Lakes in some areas and in the Plains - and I had that forecast too. One thing I can say for this winter, with relatively high confidence: it is very rare to get even three very cold winters in Montana and the Dakotas, as we have seen in some areas for 2016-17, 2017-18, 2018-19. Billings finished around 4F below the 1951-2010 average high in all three DJF seasons. Last time you had three severely cold winters in a row there was 1970-71, 1971-72, 1972-73. (1970 and 2016 were both after two El Ninos in a row, 1970, 1971, 1972 is a La/La/El sequence like 2016/2017/2018). Back to the 1930s, I can't find four severely cold winters in a row like that in that part of the US. It could still be 1-2F below normal, but you really have to bet on a warmer winter up there at this point, which has some interesting implications about the US pattern. 2018-19 was well on its way to being warm in Montana through January, but the average high in February 2019 was like 22F or something below average in Billings, coldest February since 1936 (another year with some very impressive Summer heat). A lot of years with impressive heat waves in Western Europe or the Eastern US during Summer actually end up cold somewhere in the West. The 20 hottest average high Summers in Philadelphia include winters many winters in the West that have at least brief periods of record/near record in the West.

Hello... Newman! I like 1966 as a Summer analog. I used 1966, 1966, 1987, 1992, 1993, 2015 as a blend in my Summer forecast from May linked a few pages ago. Composite July had a cool West / hot East, which looks about right. 1992-93 stayed in El Nino territory pretty late into the year, before SSTs fell off briefly for winter, and then warmed in Spring. The new Canadian should be out next week. Will be interesting to see what it has. The SST depictions start to become much better for winter in August. My guess is this winter will actually be much harder to forecast than last year. Low-solar winters, following a El Nino winter, that are not El Ninos are a pretty interesting group since 1930: 1931, 1942, 1952, 1954, 1964, 1973, 1995, 2005, 2007, 2010, 2016. Some really interesting winters in the West in those years.

Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 05JUN2019 22.9-0.4 27.2 0.6 28.6 0.9 29.9 1.1 12JUN2019 23.1 0.1 26.9 0.4 28.4 0.7 29.8 1.0 19JUN2019 22.4-0.3 26.5 0.2 28.1 0.5 29.6 0.8 26JUN2019 22.1-0.3 26.5 0.4 27.8 0.3 29.0 0.2 03JUL2019 21.8-0.3 26.1 0.2 28.0 0.6 29.7 0.9 10JUL2019 21.7-0.2 25.9 0.1 27.7 0.4 29.7 0.9 17JUL2019 21.3-0.3 25.6 0.0 27.4 0.2 29.7 0.9 Warmth continues to thin in the Eastern Nino zones. https://www.cpc.ncep.noaa.gov/data/indices/wksst8110.for PDO remained pretty positive in June too, by the way - https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_OC_PDO.htmlTable?time,PDO 2019-01-01T00:00:00Z 0.66 2019-02-01T00:00:00Z 0.46 2019-03-01T00:00:00Z 0.37 2019-04-01T00:00:00Z 1.07 2019-05-01T00:00:00Z 1.03 2019-06-01T00:00:00Z 1.09 A lot of the models have winter something like a cold Nino 1.2/3, flat Nino 3.4, warm Nino 4, with low solar, a warm Atlantic, a positive PDO, and it would be a winter following an El Nino. I think a blend of low-solar West-based El Ninos (2004, 2009), a Neutral (2003), and low solar La Ninas with a positive PDO (1984, 2016) has some merit if we have Neutral conditions. Also threw in 2007 (low solar, major La Nina) to lower the overall temperatures in the Tropical Pacific. That blend matches my weather locally fairly well for June/July (cold then warm) and seems to look like what the models currently have for winter. Looks OK for things like the QBO too. The Summer of 2012 had a big -NAO period, and then the cold went into the West. That is what the Jamstec shows, and what you get if you map the years I blended. These aren't my analogs, but this is the time of year I start to test matches for winter. The Jamstec kind of looks like a slightly warmed up version of 2012-13 in the Tropics, with a positive PDO and lower solar. If its SST depiction is correct (it probably isn't yet), the temperature idea isn't crazy given the SST look.

My point is that the ACE Index is a pretty good indicator for whether the SW is warm, average or even cool in a La Nina for highs - which gives ideas about the overall setup. Just as with El Ninos, I don't find much (any) correlation between SSTs/ONI/SSTA in Nino 3.4 in winter and highs in the SW. But things that happen coinciding with the ENSO phase do matter quite a bit. As an indicator, ACE actually beats winter or cold season AMO values in La Ninas. July still looks like my Summer analogs which assumed the El Nino would last deep into Spring or even Summer - The waters by South America are much colder than in 2017 - presumably they'll spread West with time as the last bit of warmth thins out around 170W? The Jamstec has a very cold Nino 1.2/3 in Fall, and then it warms up there as the coldest anomalies shift West.

In La Nina winters, the Atlantic ACE index is one of the strongest indicators I can find for whether the SW will be hot or not. The years when your deity of choice sends out hurricane after hurricane to ravage the shoreline from coast to coast are absolutely bone dry and severely hot in the SW US. 1933-34 (the epitome of the Dustbowl) and 2005-06, the closest year to the Dustbowl pattern in the last 20 years, both had ACE indexes of over 250 - with record heat and less than a quarter inch of precipitation in Albuquerque. The 2017-18 year was no slouch either, ACE was 225, and we roasted, but the great SOI crash of February 2018 did kind of save that winter from record heat and dryness. Right now, the ACE index is under 5 for the season - http://tropical.atmos.colostate.edu/Realtime/ Above 125, all our La Nina winter are warmer than average (49.5F).

I've been attempting to refine my methods for predicting high temperatures anomalies in the SW in La Ninas. It looks like the ACE Index in the Atlantic is a pretty strong indicator. Historically severe Atlantic hurricane seasons, in La Ninas, tend to be very hot, dry winters in Albuquerque. I'm not even convinced this will be a La Nina, but just for reference, I thought this was interesting - the three hottest La Ninas were all absolutely terrible, life destroying hurricane seasons - 1933, 2005, 2017. The two La Ninas over 250 on the Ace Index are 2005-06 and 1933-34 - essentially low-solar, Dust Bowl BS patterns in each case.