GaWx

The above noted colder GEFS trend for early Dec continued with the 12Z run.

That ext Euro phase 8 lasts 11 days, which would be the longest in Dec since 1975. I just hope it actually gets there and stays for awhile rather than curl back to 7 to stay.

1. No, ext for same run comes out a day later. —————— 2. GEFS 2 days ago: GEFS yesterday: gets to phase 8 five days earlier than any other GEFS as of then: GEFS today: curled back very slightly vs yesterday (E US cold lovers wouldn’t want a curl back into phase 7) but very similar to yesterday/look how different it is vs 2 days ago!

Yesterday’s Euro: phase 8 starts 12/14: Today’s Euro: phase 8 starts 10 days earlier, 12/4, (with a 6+day long phase 8 implied) although I’d want to make sure it isn’t curling back into 7 and staying there: last time Dec had a 6+ day long phase 8 was way back in 1995 (12/20-5):

Euro Weeklies 2m temps for 11/24-30 and this is before the very recent cooldown for early Dec: 11/17 run: 11/24 run:

The colder trend for early Dec is happening on all ensembles including GEFS: these are all for a week from today at 7PM: watch the SER disappear: @donsutherland1@bluewave

I’m wondering if despite the clear warming trend of the Euro Weeklies related to its insistence of a stubborn potent SER along with the current progged switch to a +AO if there’s lower than normal confidence due to a combo of the MJO taking a track that’s often cold (though far from always as we know) and the current very weak SPV, which typically takes 2+ weeks to bring the E US persistent dominating cold.

I didn’t pick up on this earlier and don’t know if anyone else posted this. Today’s GEFS has phase 8 starting on Dec 8th, which is about 5 days earlier than any other run:

Your post shows yesterday’s ext EPS predicting an 11 day long phase 8 for 12/14-24 averaging ~2.0 amplitude. The ext GFS is predicting a 12++ day long phase 8 for 12/13-24++ but with a much lower avg amp that with extrapolation would likely be headed to a sub 1.5 amp for the full phase 8 avg. Regarding the EPS prog, there hasn’t been an 11+ day phase 8 since back in Feb of 2010 (2/7-17). Regarding the GEFS prog of 12++ days, there hasn’t been a 12+ day long one since way back in Dec ‘75-Jan ‘76 (12/19-1/5)! There have been only two on record of 12+ days: the just mentioned one of 18 days and a 13 day long one 1/19-31/75. Also, the 15 long phase 8s (8+ days) have followed long phase 7s (9+ days) only twice out of the 15 cases although the two that did were two of the coldest. So, needless to say, I’m taking these very long phase 8 progs with a huge grain for now. Of the 15 long phase 8s at Baltimore, the ones averaging an amp of <1.8 (like GEFS has) were significantly colder in the E US on avg than those with an avg amp >1.8 (like EPS has). The GEFS-like sub 1.8 amp cases include the very cold outbreaks of Jan of 1985, Jan of 1988, Dec of 1989, and Feb of 2010 with 3+” snows (including historic snow in 2010) for all 4 in Baltimore for example. The other 3 sub 1.8 amp phase 8s had either BN (1) or NN (2) temps at Baltimore. So, even a GEFS-like moderate long phase 8 hasn’t always been cold at Baltimore but rather in most cases and with no mild cases. But half of the >1.8 amp long phase 8s were warmer than normal! So, if there’s actually a very long phase 8, I’ll be rooting for one closer to the lower amp of GEFS than the higher amp of EPS due to better prospects for cold per long phase 8 history.

There has been a +PNA in Jan for all 11 cold ENSO winters that had a -PNA in Dec since 1983-4: -1983-4: -0.31 to +0.97 -1984-5: -1.60 to +1.63 -1996-7: -1.23 to +0.63 -1998-9: -0.09 to +0.16 -2008-9: -1.41 to +0.61 -2010-11: -1.78 to +1.29 -2012-3: -1.01 to +0.55 -2013-4: -0.86 to +0.97 -2016-7: -0.35 to +0.28 -2021-2: -2.56 to +1.01 -2022-3: -0.66 to +0.22 ———— What kind of PNA are you expecting in Jan?

This isn’t a new report but I just saw it and it has the latest Jamaica death toll: Death toll from Hurricane Melissa rises to 45 in Jamaica, with 15 others still missingThe death toll is expected to rise, with officials still trying to reach two towns that remain cut off since the catastrophic Category 5 storm made landfall in western Jamaica on Oct. 28. Helicopters have been dropping food and other basic supplies in those two communities, said Alvin Gayle, director general of Jamaica’s emergency management office. He said the storm has displaced 30,000 households, with 1,100 people still living in 88 emergency shelters that remain open. https://apnews.com/article/jamaica-hurricane-melissa-haiti-cuba-killed-deaths-77db005a55d415ae84b74f6680769273

I took your advice to find out instead of assuming. Since he doesn’t post here, I knew I had to ask him how he’s done with snow in NM. His answer: We’ve done okay ish I would say overall, we have yet to have any snow though. Just had our first precipitation event since early October a few days ago. Earlier this year it snowed on my birthday so that was nice. Our last 4” winter storm warning worthy storm was back in 2015, tho Feb 2021 got close in a few spots. Any accumulating snow is a really big deal down in the Desert Lowlands & people go crazy over it here like they do in the southeast. The climatology here since the early 2000s is roughly about the same as places like Charlotte, NC. It used to snow a lot more here several decades ago but our average has cratered. ———— So, it wasn’t bad like I thought, but by no means has he been racking it up either. It sounds in between. He hasn’t gotten that much, but they normally don’t there.

I don’t think met. Eric Webb has been happy with how his abode in NM has done in recent years (since he moved there) based on his posts.

Check this out regarding 8+ day long MJO phase 8 since 1974-5: Fifteen 8+ day winter phase 8 periods back to 1974-5 in # of days, amp, (practical) # days of preceding phase 7; Balt snow/temps: -1/19-31/75: 13; amp 2.1; 3; 3.5”/MA -12/19/75-1/5/76: 18; amp 1.0; 2; 0.5”/B -1/27-2/3/76: 8; amp 2.3; 4; 1.3”/N -2/8-15/76: 8; amp 1.8; 4; T/A -2/20-28/1978: 9; amp 1.8; 3; T/B -2/17-26/82: 10; amp 1.1; 0; 5.2”/N -1/21-30/83: 10; amp 1.5; 0; T/N -1/12-22/85: 11; amp 1.6; 9; 2.8”/MB -12/31/87-1/7/88: 8; amp 1.2; 6; 4.3”/MB -2/21-29/88: 9; amp 3.2; 5; T/B -12/9-18/89: 10; amp 1.1; 4; 5.5”/MB -1/2-9/97: 8; amp 1.9; 6; 2.4”/MA -2/16-24/99: 9; amp 2.1; 4; 0.6”/B -2/7-17/10: 11; amp 1.7; 16; 19.6”/MB -2/15-23/19: 9; amp 1.9; 1 (5); 4.5”/A ——————— Analysis of above: - The # of days of phase 7 preceding these long phase 8 periods have a large majority of the time been <7 days (counterintuitive?). - Consistent with the great post today of @bluewave, look how sharply the frequency has dropped off: 5 in the 2nd half of 70s, 6 in the 80s, 2 in the 90s, none in the 00s, 2 in the 10s, and none in the 1st half of the 20s. -So, from 1974-5 through 1989-90, there was an avg. of 0.7/winter. But since 1990-1, there has been a mere 0.1/winter or only 1/7 the frequency! -But when they occur, they still have been leaning pretty hard on snow and cold based on Baltimore: Temps: MA: 2 A: 2 N: 3 B: 4 MB: 4 - So, twice as many cold as mild - Total snowfall 50.2” over these 151 days, which means an average of 0.33” per day. That’s almost 150% of the Jan-Feb 1974-2025 average daily snow of 0.23”. - So, although they’ve been much harder to come by, lengthy phase 8 periods remain highly desirable for a winter lover in the E US. @donsutherland1 *Edit 6:30PM: On average, the <1.8 median amplitudes of these long phase 8 periods have been colder and snowier than the 1.8+ amps: There were 7 phase 8 amps <1.8: -4 of the 7 lower amps were the only four MBs while all 4 of the A to MA were when the amp was 1.8+. -All but one of the 4”+ snows were during an amp <1.8.

Today’s Euro Weeklies aren’t what you want to see if you don’t want them to be warmer than yesterday: the most intense cold on the run is W and SW of Chicago and perhaps near ME. I personally hate them because the colder the better and I hate sweating in winter when I take my walks. Note that the warmest anomalies in the US are in the deep SE: Dec 1-7: very slightly warmer/strong SER: Dec 8-14: slightly warmer/stronger SER lingering: Dec 15-21: warmer/SER won’t give up Dec 22-28: SER finally weakened but slightly warmer NE vs yesterday Dec 29-Jan 4: SER staying weak but slightly warmer NE vs yesterday: