GaWx

Despite my more optimistic posts in recent days, I always still try to be objective and show everything, good or bad. The Euro Weeklies remain steadfast on a warmer than average SE and Mid-Atlantic westward/solid -PNA through almost the entire run. The torchiest still remains well to the west of the E/SE US thanks to occasional cool-offs likely largely related to CAD saving the day. The NE is not far from normal. It tries to cool off in general in the E US toward normal the last week (1/19-25), but it isn’t really exciting looking. I continue to hope that just like the models have performed in many cases for the last 3.5 weeks, that they keep busting too warm in the E US.

This has been going on a lot since the Nov 20th and earlier runs were too warm for Thanksgiving week in much of the E US.

Official totals: NYC 2.7” LGA 2.6” JFK 4.6” Newark 4.1” Islip 5.8” Upton 7.3” Based on these numbers, this storm on its own is bullish for the rest of the season there imho.

Anything to keep any torch short-lived rather than long-lived would be a win for me. Considering that the SE will have had a very enjoyably cold dominated 11/27-12/16: IF the SE can somehow manage for 12/17-31 to be only slightly warmer than normal thanks largely to cool wedges, I’ll consider it a win. Models are already significantly colder than they were just a couple of days ago for this weekend (12/20-1), which is continuing the trend of them being mainly too warm since ~Nov 20th. Is this going to extend this too warm trend through 12/21? If so, can we even trust the longer range of the ensembles? Fwiw, the 12Z GFS has 4 warm periods but all last only ~24 hours with the cool to cold days at least as prevalent.

So, your high end of 25” is near my new low end as I’m essentially 25”+ for the entire season based on today’s storm (I had no prior prediction). Are you going to raise your prediction from your 15-25” range?

Plus the indicator benchmark actually has worked better for 3” (15 out of 15) than for 4” (14 out of 15). Considering what you said (although I think the indicator has value if used correctly…this storm should more than be enough) and that 3” actually has worked better, I feel that this should already be more than enough (and we still have half the month to go, besides) to consider this a bullish indicator for NYC’s coming Jan+ snowfall to be in the vicinity of or above the 30 year normal of 24” for Jan+. Thus, I’m now predicting NYC will have at the very least 21” from Jan onward on top of whatever the Dec total ends up at: Season…Dec NYC SN...Jan+ NYC SN 20-21…..10.5”….28.1” 17-18……7.7”……33.2” 16-17……3.2”……27.0” 10-11…..20.1”…..41.8” 08-09…..6.0”…..21.6” 05-06…..9.7”…..30.3” 00-01…..13.4”…..21.6” 95-96…..11.5”……64.1” @bluewave@donsutherland1

The 48 hour trend on GEFS has been to a -NAO. Keep in mind what we just saw for last week, when the Nov 28th forecast had a +NAO and it ended up as a strong -NAO. Dec 12th GEFS: Dec 14th GEFS:

Any chance LGA can beat 3.6”? If so, it would mean their heaviest single storm total in nearly 4 years (Jan of 2022) and heaviest in Dec in 5 years.

On Nov. 4th, I made airline reservations with some friends to arrive this morning at LaGuardia from Savannah at 11:14AM for my first NYC trip since the summer of 2011 and their first trip there ever. Due to unexpected issues that suddenly came up with my friends, we had to cancel the very next day (fully refunded back to CC immediately). This had been emailed to me from what I had booked: Sunday 14 Dec 25 Flight Information Delta Air Lines /Republic Airways Delta Connection DL 5603 Savannah, New York La Guardia, 09:05 AM 11:14 AM Terminal C It’s a good thing we canceled this trip because this originally scheduled departure of 9:05AM from SAV has still not taken off and as of now isn’t scheduled to depart til 12:30PM! SAV Airport info 2h 9m flight. 2h 9m LGA Airport info Savannah · Sun, Dec 14 Estimated departure 12:30 PM Originally scheduled departure: 9:05 AM 9:05 AM Terminal - Gate 9 New York · Sun, Dec 14 Estimated arrival 2:27 PM Originally scheduled arrival: 11:14 AM 11:14 AM Terminal C Gate 98

LE 7-10AM: LGA 0.13” JFK 0.17” These compare to the NYC 0.14”.

CPK station picked up 0.14” of liquid equivalent 7-10AM since the 7AM 1.1” measurement per the link below. When adding what they got since 10AM with it still falling, they could approach 0.20” liquid equivalent since the 1.1” measurement. https://forecast.weather.gov/data/obhistory/KNYC.html

The 1.1” at NYC was as of 7AM when it was having “light snow” (vis 1 mile). Since then, the vis dropped to 0.75 miles vis (still called light snow) at 8 AM followed by moderate snow at both 9AM and 10AM with only 1/2 mile vis. One would think they’ll have much more than 1.1” when this is done (shortly).

Chris, So, your data shows that 3”+ actually worked better with a perfect 15 out of 15 with regard to predicting snowfall Jan+. Why not consider using 3” as the cutoff instead of 4”? @donsutherland1

Well, I just saw it updated for Dec 11th. It, indeed, looks like it finally was headed back toward phase 8. Technically, they’re calling 12/11 a very weak phase 7. Good chance I think that it returned to phase 8 on 12/12 (inside the circle)! We should know by tomorrow evening about 12/12.

A 4” snow seems like it would be considered quite a notable and impactful snow there and in most places. I understand that it’s not considered “major” up north, but down south it sure is in most areas like Atlanta. In Savannah, that would easily be in the historic category like the absolutely amazing and unheard of nearly 3” of mainly sleet (some snow finally fell pretty late into the storm) I got in January. Will NYC reach 4”? That’s the magic amount for a total in Dec that @bluewaveand @donsutherland1have said is an excellent predictor in La Niña winters for above average for Jan+.

The 12/8-10 MJO were all in very weak 5-6 (essentially neutral):

In the interest of showing objectivity, I expect the 12Z Euro, which is about to be released, to not be as cold as the 0Z that I posted 3 temp anom maps from. But the overall trends toward not as warm, more CAD, and instability of models within just a week seems real to me and tells me not to bet the farm at least yet on a mainly mild 12/18-31 mid-Atlantic south like has been suggested by ens. means. We’ll see. Edit for 12:55 update on 12Z Euro vs 0Z: -12/20 map not quite as cold but still BN -12/22 and 12/25 maps much warmer ————— I expected this because 0Z was such a cold run and thus appeared to go too far. But regardless, 12/20 is overall still trending colder in model consensus and models remain unstable telling me to not bet too heavily on late month mild domination.

The dreaded 0Z Euro E US torch: awful! 12/20: 12/22: 12/25:

I remain on “hope the Euro Weeklies for Jan fail miserably mode” because not only did today’s hold onto the mild pattern (though consistent blowtorch still well W of the E US thanks probably to refreshing CAD at times), they warmed that final week of the run (1/19-25) vs yesterday: H5 yesterday’s run for 1/19-25: H5 today’s run for 1/19-25: 2m yesterday’s run for 1/19-25: 2m today’s run for 1/19-25: Edit: Lakes to NE still average near normal temps almost every week of the run.

NG bulls want the opposite of this EPS HDD trajectory (see left graph): the cold part through 12/15 was dialed in to prices many days ago:

https://s2s.worldclimateservice.com/climatepanel/ Then click on 2nd map on right.

WCS: Pretty steady for now but still within a longer term (6 month) rise:

Today’s GEFS PNA forecast is the most negative for this Dec that I can recall: 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: -1.6/+1.0 (rose 2.6) So, average PNA rise Dec to Jan for these was a whopping 1.8! Dec temperature anomalies: coldest N Rockies to N Plains/mild much of SE 1/3: Jan temp. anomalies: coldest shifts 1,000 miles SE and warmth gone https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table

Natural gas is down still another 3% on the day, which brings the total drop since the peak of 8 days ago to a very steep 25% on an anticipated much warmer E US pattern (though maybe not to a torch in the means as I stated in my prior post) starting mid to late next week and continuing for the foreseeable future! At least that’s some good news for future heating bills. @Stormchaserchuck1

The Euro Weeklies suggest the most intense and persistent torching will actually be concentrated well to the W and SW of the E coast. So, whereas a big warmup vs the current very cold pattern is coming on all models, that big warmup in the E US appears to take it to only moderately warmer than normal instead of downright torchy when averaged out.