GaWx

I see that now on the Euro Weeklies. H5 has risen significantly in the Arctic, especially over Greenland, over the last 3 days. Is this an adjustment due to the decreasing mean 60N 10 mb wind? Today’s mean low on Mar 13th dropped from yesterday’s -18 to -20, lowest EW yet. That’s a very strong reversal to either a major SSW or FW. 2m temps in the E US are still strongly favoring AN to NN over BN but are somewhat less mild than yesterday most weeks. Today’s Euro Weeklies favor a very early FW: all members sink to -10 or lower.

I’ll now look at current Nino 1+2 anomalies: way up there due to 2.3 to 2.5 C of warming just since late Jan! CDAS: +1.46 CRW: +1.63 OISST: +1.54 Feb OISST came in at +0.69. Mar looks to be aiming for well over +1. Per history what might that portend for 2025-6 ENSO? First of all, a reduction of ~0.5 may be recommended to take into account GW/relative global tropical temps. But even so, an adjusted Mar might still have a good shot at +1+. -3/2023 Nino 1+2 (on the way to El Nino) was way up at +1.52! Back then RONI was ~0.3 cooler than ONI. So, the relative equiv 3/2023 1+2 may have been ~+1.2. For Mar 2025 to reach that, the actual 1+2 may need to be way up at +1.7. That does seem possible with the current OISST already up at +1.54. Feb 2023’s 1+2 of +0.71 was similar to Feb of 2025’s +0.69. -But OTOH, Feb/Mar of 2017 were way up at +1.14/1.83 and that didn’t head to El Niño as instead 2017-8 was a 2nd year La Niña. -Feb/Mar 1998/1983 strong warmth were leftover from just ending super El Niños. So, they’re not comparable. So, which of 2023 (incoming El Niño) and 2017 (no incoming El Niño) is more likely?

I had thought that the daily cyclonicwx OISST Nino 3.4 SSTs had stopped updating on Jan 5th. It turns out that that wasn’t the case and that the link had changed. So, here is the OISST 3.4 anom as of March 2nd, which is up to +0.043 and is almost as warm as the CRW’s +0.086:

Modoki La Niña? Also, isn’t that +1.1 overdone due to GW? Same reason RONI better than ONI? On a RONIlike basis, Nino 1+2’s +1.1 may be the equivalent of only, say, +0.6.

I’m sure you know NG is +7% today. I doubt that that big of a rise is mainly due to colder models (even if they are colder), especially this late in the heating season, and am instead educatedly guessing it is due to seasonals due to the background state of a 238 bcf deficit vs 5 year avg storage compared to above avg storage as recently as midwinter. This seems more like a delayed effect from last week’s record breaking draw for so late in the season that of course was a result of the prior week’s extreme cold.

Why not just go by RONI? It dipped way down to moderate (-1.09 in NDJ) and that was the 7th straight -0.5- trimonth (starting with the rounded -0.46 of MJJ). Isn’t that enough?

The 12Z EPS mean has increased from about nothing to very light snow that is near the 12Z GEFS amounts in NC: But the EPS mean temp anom map doesn’t even have a Barney Rubble! Looks more like a Pebbles Flintstone. Good luck with that in March:

12Z Euro fwiw has a little snow on Mar 9 outside of the mtns in NW SC/SC NC: This is at the far N end of the qpf: It has just a mini-Barney (Barney Rubble?) during a time of year that daddy-Barney may be needed as one of our posters previously sort of put it:

For NC, 12Z GEFS has reverted to mainly a mountain upslope event: Compare this to the 18Z GEFS, which had 1-2” in the Triangle/Triad. Now it is only 0.2”-0.3”.

But per RONI and MEI v2 it will be an unofficial La Niña, right?

Feb 30 mb QBO fell to +10.55 from Jan’s +12.11 and the recent peak in Nov of +13.78. It will likely be negative by summer with very likely early autumn at the latest per historical patterns: https://psl.noaa.gov/data/correlation/qbo.data

WCS PDO just rose to -0.18 on 3/1/25, its highest daily since 3/22/24!

OHC and Nino 3.4 SSTs have recently been pretty rapidly rising with slightly warm biased CRW up to +0.086, cold biased CDAS up to -0.222, and OHC up to just above -0.6 from ~-1.25 late Jan (OISST dailies graph hasn’t been available since Jan 5th!):

KSAV (official station at airport) had a low of 32 while Hunter AAF (close to the city and not as far inland) had 34. KSAV has had an average of 1 freeze in March. That could very well end up being the last and only one. Brunswick, GA, a traditional cold spot on radiational cooling nights got down to at least 31. The contrast between inland and coastal stations was quite large due to a lack of near calm winds on the coast, with a partial onshore component from the NNE to NE. Coastal waters temps are mainly 55-56. St. Simons only got down to the upper 40s vs Brunswick’s ~31! Charleston downtown/Harbor got down only to ~44 vs well inland CHS’s 29! Ft. Pulaski likely only got down to ~49 and possibly as high as 50 vs Hunter’s 34 and KSAV’s 32! Sapelo Island, one of the traditionally colder island locations got at least down to 41.

0Z GEFS 10:1 24 hour snow: lower amounts vs 18Z GEFS but still decent signal

Not gone at 0Z. Still there and similar:

The 0Z 3/2/25 GFS/GEPS had a min of -21 on 3/12 and 3/13, respectively. 0Z GEFS had -17 on 3/13 with 100% of members having a reversal to -5 or lower. And the 0Z Euro had -18 on 3/13 as we know. So, it is unanimous for a substantial reversal.

Yeah, 18Z GEFS strongly for an ensemble mean followed the 18Z GFS fwiw (thus I don’t expect this to hold up on the 0Z):

I already posted the link there yesterday after seeing it here. Andy H being fired was kind of a shock.

Today’s Euro Weeklies mean has an even stronger reversal next week with low mean of -18 vs -10 on yesterday’s run and 100% of members having a reversal that goes at least down to -8!

NYC had these winters with both sub 32 F DJFs and <20” of total seasonal snowfall: -1967-8: 19.5” -1962-3: 16.3” -1958-9: 13.0” -1900-01: 9.1” -1871-2: 14.4” https://www.weather.gov/wrh/Climate?wfo=okx

Ready or not it is now evident that either a major SSW or a very early FW is very likely on the way within ~10 days. This (today’s Euro Weeklies) shows ~95 of 100 members reversing by Mar 14th. The mean gets way down to -10 on 3/14. Today’s has the strongest signal yet. This would be consistent with Joe D’Aleo’s study showing a strong tendency for a major SSW during +QBO/strong winter solar. Solar for DJF came out to ~148: *Edit: there’s no indication this will lead to increased snow. There’s always some chance this kind of thing will lead to BN temps in 15+ days. But as of now the models don’t even show that. Even if it were to do so, that may not mean much, if any, snow for the NE US since it will be so late in the season. @snowman19 Kudos to @40/70 Benchmarkfor predicting this for some point in the late season with confidence.

New Euro Weeklies: mild to warm Mar 10th through Apr 14th

Here’s the 12Z Euro snowfall at 10:1 through the same time:

Yesterday’s Euro Weeklies and 0Z extended GEFS (today’s not out yet) actually had the highest chances yet of any of these runs for a mid-Mar major SSW or FW fwiw: