GaWx

Here’s the GEFS NAO: week 2 of this and the EPS have gotten much more negative just since 24 hours earlier and are now close to the strongest -NAOs of all runs at least since Oct 31st per WxBell’s history that goes back that far:

Chuck, The strongest Jan +PNAs for +ENSO were these: 1977: +1.8 from +0.5 in Dec 1983: +1.2 from +0.8 in Dec 1987: +1.0 from +1.4 in Dec 1992: +1.3 from +0.5 in Dec 2003: +1.3 from +1.6 in Dec 2010: +1.3 from +0.3 in Dec 2016: +2.0 from +0.8 in Dec So, avg Dec preceding +1+ +ENSO Jan PNA was +0.8. But avg Jan following +1+ +ENSO Dec PNA was only +0.5 though it was skewed by 1954.

Chuck, Let’s see. I’m looking now at +ENSO 1+ PNA Decembers to Januaries: there were 8 cases: - 1953-4 +1.3 to -1.1: drop of 2.4 - 1963-4 +1.8 to +0.2: drop of 1.6 - 1969-70 +1.8 to +0.6: drop of 1.2 - 1986-7 +1.4 to +1.0: drop of 0.4 - 1997-8 +1.2 to +0.7: drop of 0.5 - 2002-3 +1.6 to +1.3: drop of 0.3 - 2006-7 +1.9 to +0.7: drop of 1.2 - 2023-4 +1.2 to +0.5: drop of 0.7 - avg drop 1.0 - avg drop much higher for 1st 3 cases (1.7) vs last 5 (0.6) ———— Your thoughts?

Hey Chuck, Here’s a post I made on Friday going all of the way back to 1950 that shows that for some reason (possibly randomness) the sharpest rises from a sub -1 PNA Dec to Jan have occurred since 1984-5 (CC related?): “This implies the realistic chance for a sub -1 Dec PNA. Whereas that’s bad news for those wanting E US cold in the 2nd half of Dec in the MidAtlantic/OH Valley south, it isn’t necessarily bad news for January prospects. That’s because in the vast majority of cases for -ENSO, the PNA in January rose sharply from Dec: PNA Dec/Jan for -ENSO for strongly -PNA in Dec - 1955-6: -2.1/-1.3 (rose 0.8) - 1961-2: -1.2/-0.1 (rose 1.1) - 1964-5: -1.7/-0.2 (rose 1.5) - 1971-2: -1.5/-1.4 (rose 0.1) - 1984-5: -1.6/+1.6 (rose 3.2) - 1996-7: -1.2/+0.6 (rose 1.8) - 2008-9: -1.4/+0.6 (rose 2.0) - 2010-1: -1.8/+1.3 (rose 3.1) - 2012-3: -1.0/+0.6 (rose 1.6) - 2013-4: -0.9/+1.0 (rose 1.9) - 2021-2: -2.6/+1.0 (rose 3.6) So, average PNA rise Dec to Jan for these was a whopping 1.9!

Today’s GEFS is progging ~-1.7 PNA for Dec as a whole. That would be ~5th strongest -PNA since 1950. But what were similarly strong -PNA Dec followed by in Jan since 1984-5 during -ENSO? 1984-5: from -1.6 to +1.6 2008-9: from -1.4 to +0.6 2010-1: from -1.8 to +1.3 2021-2: from -2.6 to +1.0 All 4 of these Januaries were cold in the E US.

The radiational cooling in much of the SE has been quite impressive the last 4 hours!

This afternoon’s walk was another pleasant one due to still pretty dry air (dewpoints mid 30s), blue skies, and light winds though it was ~20 warmer (60 vs 40). So, though it was pleasant, it felt better and more invigorating yesterday.

Natural gas is down still another 3% today making it a total of a whopping 29% just since the high of Dec 4th!

The two forums are very intertwined between many (probably a majority) of its members also being members and former posters here as well as some currently posting at both (in some cases with different names). I’m sure many read both boards daily.

For me it wouldn’t be “suffering”. It isn’t anything like, say, bad health/getting sick. “Suffering” is too harsh a word from my standpoint even though it’s not at all what I prefer as I want it colder than normal at any point in the year. The good thing is that it’s my favorite season of the year and warmer than normal in winter is still much colder than, say, below normal in summer. In addition, this warmer period will be following one of the coldest 3 week periods from Thanksgiving through the first 17 or so days of December I’ve ever experienced and easily the coldest since 2010. Even if it’s going to be mild for awhile, forecast discussions would still be interesting in the most volatile season of all, winter.

Ray, If you mean the link to the site that produces the graphs of 10 hPa/60N mean zonal wind back to 1978-9, those could be produced by going in here: https://acd-ext.gsfc.nasa.gov/Data_services/met/ann_data.html#ncep_clim_stats_nh

Also, Dec of 2016 had a +WPO and Dec of 2022 had a neutral WPO unlike the -WPO of Dec of 2025 fwiw.

Our airport had a low of 25 for the 2nd morning in a row. My lowest was likely ~30 vs 26.6 yesterday. But the freeze last night was radiational rather than advective/windy with a much longer duration of ~9 hours.

Thanks. That’s based on my 1st list, which is of those Decembers that had 1+ days dipping lower than -3.48. But those Decembers didn’t necessarily have a solid -WPO dominating through the entire month. One of those Decembers, 1996, actually averaged a +WPO overall. Also, 1983 and 1977 didn’t average a negative enough WPO. And there were a bunch of Decs left out of that 1st list that had a very -WPO with it dominating throughout but that didn’t have at least one day dip below -3.48 like 2013, 2010, 2009, 1995, 1980, 1961, and 1956 that make them good -WPO Dec analogs. OTOH, the 2nd list included some that weren’t -ENSO through the winter or at all like 2009, 1989, 1980, and 1956. In addition, 2005 and 1995 had a moderate or strong +PNA in Dec. So, what are we left with for the best analogs based on solid -WPO throughout Dec, -ENSO through the winter, and a moderate to strong -PNA in Dec? 2013, 2010, and 1961. Of these three, the PNA flipped to positive in Jan in 2014 and 2011 and to neutral in Jan of 1962. So, the closest -ENSO/Dec -WPO/Dec -PNA analogs are 2013, 2010, and 1961.

I’ll check now for December. These 9 were solidly -WPO Decembers dominating throughout the entire month: 2013, 2010, 2009, 2005, 1995, 1989, 1980, 1961, and 1956. Of these: 1) Cold in the S Plains? 2013, 2009, 2005, 1989, 1961 2) Near normal S Plains? 2010, 1995 3) Mild S Plains? 1980, 1956 So, strong -WPO Decembers leaned somewhat to the cold side in the S Plains, but only 5 of 9 averaged cold. It looks like this year may end up averaging near normal based on a cold 1st half and mild 2nd half. But we’ll see. PNA for these 9 Decembers: 2013: moderate -PNA 2010: strong -PNA 2009: weak +PNA 2005: strong +PNA 1995: moderate +PNA 1989: moderate +PNA 1980: weak -PNA 1961: strong -PNA 1956: weak -PNA So, PNA for these solidly -WPO Decembers is very mixed.

Well, as of Dec 13th, the MJO still hasn’t returned to phase 8! It was in 8 only Dec 3rd-7th. Dec 8th-13th have all been in very weak (essentially neutral) phases 5-7. I still think it has a good chance to get back into 8 very soon, but we’ll see:

The 12/13/25 WPO of -3.48 is the most negative WPO on any day in December since 12/25/1996! The only Decembers since 1948 with at least one day lower than -3.48 are: 1996, 1989, 1983, 1977, 1966, 1955

But the Euro Weeklies still look mainly mild in most of the E US S of the northern fringe with the torchiest still W of the E US.

I just took a walk in very refreshing and invigorating 40 degree single digit dewpoint air along with beautiful blue skies and light winds. I love this wx!

OHC has been rising sharply the last 30 days:

Yeah, unfortunately here’s the ugly truth for E US cold preferrers (NG is down another 1% today making it a whopping 26% drop from the peak 11 days ago): left graph has EPS HDD (latest out/0Z in purple); note the cliff dive it takes from today’s very cold 33 HDD, which is a whopping 10 above the normal of 23, to 12/18’s mild 18, which is 6 below the normal of 24! It later gets as low as 15 on 12/25, which is 10 below the normal of 25!

It looks like that’s the case (rotated quickly through and out) per 850 temps on the models: 7PM in degrees C last night near the coldest brrrrr! 1AM last night had already warmed some with coldest already rotating to E NC/VA: 7AM this morning had warmed a lot everywhere!

Indeed. The official RMM record always puts it in one of the 8 phases (6, 5, 6, 7, 7 per the bolded below for 12/8-12), but, regardless, this is about as bullseye/weak as you can get for a 5 day period: 2025 12 8 0.16185258 0.31161267 6 0.35113916 Gottschalk10_method:_OLR_&_ACCESS_wind 2025 12 9 0.23143651 0.18252292 5 0.29474986 Gottschalk10_method:_OLR_&_ACCESS_wind 2025 12 10 0.12193847 0.22910139 6 0.25953120 Gottschalk10_method:_OLR_&_ACCESS_wind 2025 12 11 -9.49310213E-02 0.16355878 7 0.18911207 Gottschalk10_method:_OLR_&_ACCESS_wind 2025 12 12 -2.23553125E-02 8.96196812E-02 7 9.23658386E-02 Gottschalk10_method:_OLR_&_ACCESS_wind https://www.bom.gov.au/clim_data/IDCKGEM000/rmm.74toRealtime.txt

MJO still hadn’t gone back into 8 as of 12/12 with it technically still in a very weak 7 per the record: so, 12/8-12 in very weak phases 5-7 essentially neutral with it not far from the center

No, I’ll pass lol. 26.6 is coldest I saw for here (at 7:40 AM) The official (airport) low was 25 as of 7AM.