raindancewx

The PDO finished Nov-Apr at -0.2. Lowest in a long time on the JISAO method. Will be interesting to see how the winter plays out if that continues. Been a long while since we've had a La Nina with a -PDO for winter. Nino 4 is still very warm, surface, even subsurface in some ways - that is why I'm skeptical of a major La Nina. But I think a 25.5-26.5C DJF in Nino 3.4 is pretty likely.

Cooling continues. Possible we flip some areas to below average at the surface over the next two-three weeks. Still need a lot of cooling after that to get to -0.5 at the surface. I think it's possible around July though. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 04MAR2020 27.5 1.1 27.0 0.1 27.5 0.5 29.3 1.1 11MAR2020 26.7 0.3 27.5 0.5 27.7 0.5 29.3 1.2 18MAR2020 26.9 0.5 27.6 0.4 28.1 0.8 29.4 1.2 25MAR2020 27.0 0.8 27.5 0.3 27.9 0.5 28.9 0.6 01APR2020 26.8 0.8 27.9 0.6 28.1 0.6 29.1 0.7 08APR2020 26.5 0.8 28.0 0.6 28.2 0.6 29.4 1.0 15APR2020 25.6 0.1 28.2 0.7 28.5 0.7 29.4 0.9 22APR2020 25.4 0.2 28.1 0.7 28.4 0.6 29.2 0.7 29APR2020 25.1 0.1 27.7 0.4 28.2 0.4 29.0 0.4 06MAY2020 24.8 0.2 27.4 0.2 28.0 0.2 29.0 0.3

Fairly rapid cooling this week at the surface. Still a ways to go though. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 04MAR2020 27.5 1.1 27.0 0.1 27.5 0.5 29.3 1.1 11MAR2020 26.7 0.3 27.5 0.5 27.7 0.5 29.3 1.2 18MAR2020 26.9 0.5 27.6 0.4 28.1 0.8 29.4 1.2 25MAR2020 27.0 0.8 27.5 0.3 27.9 0.5 28.9 0.6 01APR2020 26.8 0.8 27.9 0.6 28.1 0.6 29.1 0.7 08APR2020 26.5 0.8 28.0 0.6 28.2 0.6 29.4 1.0 15APR2020 25.6 0.1 28.2 0.7 28.5 0.7 29.4 0.9 22APR2020 25.4 0.2 28.1 0.7 28.4 0.6 29.2 0.7 29APR2020 25.1 0.1 27.7 0.4 28.2 0.4 29.0 0.4 The Nino 4 cool down is encouraging for a La Nina. The European has been trying to get it negative sometime mid-summer and that's almost a precursor for a La Nina. Solar activity for the 12-months ending April 2020 was at about 2.5 sunspots/month - so we should be at or very near the absolute floor of this solar cycle too. If that's the case the NAO may behave pretty differently next winter. May v. Apr is one of the better indicators for it at a long-lead, along with Sept v Mar. 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 0.7 0.6 0.5 0.3 0.1 0.1 0.3 0.5 0.5 Year DJF JFM FMA MAM AMJ MJJ JJA JAS ASO SON OND NDJ 2020 0.5 0.6 0.5

Since 2000 we haven't really had a La Nina with a peak below 25.0C in Nino 3.4 in winter and Nino 4 remains very warm. That is my main skepticism for a big time, major La Nina. I was playing with it the other day - and I think something like this may end up happening given how warm Nino 4 is still. Peak cold around 120W, Nino 4 never completely cools off. PDO still negative though. Would "feel" like a La Nina, but we'll see. Obviously it is way early for this. Nino 4 over 29.0C makes it hard for Nino 3.4 to get below 26.0C though. I do think Nino 3 may be pretty cold - in the past winter, Nino 3 had a lot of trouble staying warm for whatever reason.

YR MON 130E-80W 160E-80W 180W-100W 2019 10 0.38 0.49 0.70 2019 11 0.34 0.34 0.26 2019 12 0.37 0.45 0.35 2020 1 0.33 0.48 0.49 2020 2 0.32 0.51 0.53 2020 3 0.10 0.19 0.33 2020 4 -0.16 -0.19 -0.22 Subsurface heat for 100-180W is now negative at the equator down to 300m. Usually big drops month.month correspond to a warm month in the US - we'll see. El Nino is over - these measures were still positive last April. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt

New Canadian has trended the Nino regions colder. I think it is a bad initialization though - it shows Nino 3.4 pretty cold already in May which doesn't look likely going by the weeklies since the surface is still warm. May is forecast to be quite warm though -

There is a pretty strong cyclical nature to date of final measurable snowfall here. The repeatable part of the curve seems to be 60-years, so we're around 1960?

Tentative idea from me is a cool-ish start to Summer, before the heat turns on later, relative to time of year. Not expecting a particularly robust Monsoon, but just starting to look at Summer now. If we go into a La Nina in winter, there is often a huge September for moisture if we are to have a hot/dry winter. Think 2005, 2008, 2013, 2017 which were all pretty dry and cold neutral to La Nina setups.

It does look like we are trending toward a La Nina - but there is still a lot of warmth at the surface to be eroded. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 01APR2020 26.8 0.8 27.9 0.6 28.1 0.6 29.1 0.7 08APR2020 26.5 0.8 28.0 0.6 28.2 0.6 29.4 1.0 15APR2020 25.6 0.1 28.2 0.7 28.5 0.7 29.4 0.9 22APR2020 25.4 0.2 28.1 0.7 28.4 0.6 29.2 0.7 The data is 'centered'. So this is through April 25th. April will be the month to make this event 'official' as an El Nino. But of course the El Nino is dead now, and CPC's method of classifying is very laggy. Nino 4 does still look like it will be warm for a while.

The core of the cold water anomalies right now are not in Nino 4 - so any transition to a La Nina will likely go through something like an El Nino Modoki look first (warm around 170W), colder east/west of there. The warmth east of 150W is in trouble pretty soon though.

April looks like it is going to clinch 2019-2020 as an official El Nino. But the subsurface heat is gone now. Still very warm in Nino 4 too. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 05FEB2020 26.4 0.8 26.1 0.0 26.9 0.2 29.3 1.2 12FEB2020 26.1 0.1 26.6 0.3 26.8 0.1 28.9 0.9 19FEB2020 26.5 0.3 26.7 0.2 27.4 0.6 29.2 1.1 26FEB2020 27.2 1.0 27.1 0.4 27.4 0.5 29.1 1.0 04MAR2020 27.5 1.1 27.0 0.1 27.5 0.5 29.3 1.1 11MAR2020 26.7 0.3 27.5 0.5 27.7 0.5 29.3 1.2 18MAR2020 26.9 0.5 27.6 0.4 28.1 0.8 29.4 1.2 25MAR2020 27.0 0.8 27.5 0.3 27.9 0.5 28.9 0.6 01APR2020 26.8 0.8 27.9 0.6 28.1 0.6 29.1 0.7 08APR2020 26.5 0.8 28.0 0.6 28.2 0.6 29.4 1.0 15APR2020 25.6 0.1 28.2 0.7 28.5 0.7 29.4 0.9

For snow, the NE was my biggest issue. But generally, the maps I use have pretty incredible snow totals for the West in the high terrain for July-June. I can't get on the site to update the running snow total % map - but it looked pretty decent to me outside the NE, west TX and CA.

The 1951-2010 average temperature in Nino 3.4 is 26.5C for Dec-Feb. A pretty healthy La Nina to me would be under 25.5C. By modern standards, with Nino 4 semi-perpetually warm, I might fudge that by 0.2C. The 2010-11 event was 1.3C below the long term average in winter (25.2C). None of the modern La Ninas since 2000 match the colder/older ones, at <25.0C for a winter, which would be -1.5C or colder long term.

Nino 4 looks like it could finish in the 29.0-29.4C range for April 2020. Not exactly a lot a strong cold or La Nina signal historically. In fact it seems almost impossible to get a strong or long-lasting La Nina with Nino 4 that warm going by the historical record. This is the composite of winters after 29.0-29.4C Nino 4 in April. Really only 1995-96, 2005-06, 2010-11 as La Ninas. Only 2010-11 is strong.

I'll be very curious to see the final snow totals for the West in May, but I was pretty optimistic for the high areas for snow for Oct-May last Fall- that looks pretty good overall. The models / SOI are already hinting at some kind of big system at the end of the month with a lot more snow and severe weather too.

The AMO (+0.363) for March, and PDO for March (-0.82) combination is the worst possible outcome for the Southwest to get a lot of precipitation long-term, especially if a La Nina does develop. The ideal is a -AMO, with a positive PDO. We're opposite that now. I'm still pretty skeptical of a La Nina. Nino 4 is real warm for a La Nina to develop. I think it needs until June to fall to average warmth, even with rapid cooling.

Rain yesterday into the early morning today went over to snow. Briefly accumulated about half an inch in the city, after weeks in the 60s/70s. Will be interesting to see what the official snow measurement is - they recorded 0.10" as snow, but all above freezing. Probably only 0.2" or something.

Happy mid-April from New Mexico. Snow accumulating in Albuquerque. This is East of town

Snowing here. Never good for the Plains for tornado activity if it snows in Albuquerque in Spring.

Still El Nino. 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 23OCT2019 19.7-1.3 25.0 0.1 27.3 0.6 29.7 1.0 30OCT2019 20.8-0.4 25.4 0.5 27.4 0.7 29.6 0.9 06NOV2019 20.7-0.6 25.2 0.3 27.2 0.5 29.3 0.7 13NOV2019 20.9-0.6 25.6 0.6 27.4 0.8 29.6 0.9 20NOV2019 21.7-0.1 25.6 0.6 27.4 0.7 29.5 1.0 27NOV2019 22.5 0.4 25.4 0.4 27.0 0.4 29.3 0.8 04DEC2019 22.5 0.1 25.3 0.2 26.9 0.3 29.4 0.9 11DEC2019 23.1 0.5 25.5 0.4 27.1 0.5 29.5 1.0 18DEC2019 23.3 0.4 25.5 0.3 27.2 0.6 29.5 1.1 25DEC2019 23.6 0.3 25.5 0.2 27.0 0.4 29.5 1.0 01JAN2020 23.7 0.1 25.7 0.3 27.2 0.7 29.6 1.2 08JAN2020 24.3 0.2 25.9 0.4 27.1 0.5 29.3 1.0 15JAN2020 24.2-0.2 25.6-0.1 27.0 0.4 29.2 0.9 22JAN2020 24.6-0.2 25.8 0.0 26.9 0.3 29.1 0.9 29JAN2020 25.3 0.2 26.1 0.2 27.4 0.8 29.3 1.1 05FEB2020 26.4 0.8 26.1 0.0 26.9 0.2 29.3 1.2 12FEB2020 26.1 0.1 26.6 0.3 26.8 0.1 28.9 0.9 19FEB2020 26.5 0.3 26.7 0.2 27.4 0.6 29.2 1.1 26FEB2020 27.2 1.0 27.1 0.4 27.4 0.5 29.1 1.0 04MAR2020 27.5 1.1 27.0 0.1 27.5 0.5 29.3 1.1 11MAR2020 26.7 0.3 27.5 0.5 27.7 0.5 29.3 1.2 18MAR2020 26.9 0.5 27.6 0.4 28.1 0.8 29.4 1.2 25MAR2020 27.0 0.8 27.5 0.3 27.9 0.5 28.9 0.6 01APR2020 26.8 0.8 27.9 0.6 28.1 0.6 29.1 0.7 08APR2020 26.5 0.8 28.0 0.6 28.2 0.6 29.4 1.0

Also, the European has Nino 3 warming quite a bit the next few months, with Nino 3.4 in El Nino conditions in April. The decay of warmth is forecast to be roughly west to east, with 4 dropping fastest, then 3.4, then 3.

Euro has been showing a pretty good snow storm for New Mexico on its last few runs. The timing is pretty consistent with the huge SOI crash early month, and also the 3.5 month lag to the late December system. Still amazes me that since I've lived in Albuquerque we've had more snow in the city in April than in March, but, it looks like 1-3" is possible here if temps are cold enough and the wind cooperates. Haven't looked in detail yet though, since location for the precip shield will continue to change.

The JISAO PDO value is in for March 2020 - Nate Mantua sent it out today. -0.82 is lowest in a very long time - since October 2013 https://oceanview.pfeg.noaa.gov/erddap/tabledap/cciea_OC_PDO.htmlTable?time,PDO

The European has been showing a pretty big snow storm for mid-April for New Mexico. It does coincide pretty well with the huge SOI crash 4/1 to 4/3 - big storms over the SW tend to follow big crashes. The crash was +5 to -16 in two days.

Actually think May will be pretty active, even for the time of year.