GaWx

0Z Euro: Similar position to GFS/CMC:

0Z GEFS mean (10:1) through Feb 21st

I since edited my wording about the 0Z CMC because it is actually about as far SE as the 0Z GFS. The reason the CMC’s wintry precip is centered further NW is that it’s Arctic high isn’t as strong/cold.

The latest Euro Weeklies got even colder for these two weeks (what would be coldest last half of Feb since 2010 for many) with a strong +PNA/-AO to start with +PNA continuing and suggests a crazy Feb with a mainly mild 1st half and mainly cold 2nd half, something not seen since 1999 in much of the SE: Feb 17-23 Feb 24-Mar 2:

0Z CMC fwiw: much less cold Arctic high than GFS

The GFS rang?

Hopefully Brick is in bed. If he sees this before bed, a good night’s sleep for him may be in jeopardy. But I’d still be in favor of a 2nd Brick storm thread. So, he needs to get plenty of rest beforehand.

It looks amazing for many in the SE and would be the biggest storm of the winter to date for most of NC/SC and far N GA. But always be wary about the favored NW trend, especially because this is still 8-9 days away. Any thoughts about that? Will the preceding potential -5 AO combined with a solid +PNA minimize any NW trend? Whereas Jan 10-11 had a typical NW trend, Jan 21-2 did not due to the massive Arctic high.

In addition to the snow on the 0Z GFS, check out the sleet and ZR:

Today’s high of 61 was the coolest high at KSAV since Jan 27, the last daily mean BN. Today’s mean was still slightly AN.

To their credit, the GEFS and EPS means never came that close to a 60N 10 mb wind reversal. The Euro Weeklies dropped several days in a row and got to as low as +15 on Feb 15th (Feb 2nd run) but that was it. Then it quickly headed back up. Several GFS ops had a major SSW and that in combo with the EPS falling to +15 and realizing that the GFS twice lead the way the prior 2 winters along with Joe D’Aleo’s study showing a high correlation of high solar/W QBO got me thinking there was a decent chance. Did Jim Hughes rule out a mid Feb major SSW two weeks ago? If so, kudos to him. But if not he’s just stating what’s obvious now.

Today’s GEFS based AO forecast is even more impressive for 2/15-18 as it suggests a dip to ~-5 is quite possible then! That would be lowest daily AO since 2/10-11/2021! Other Feb sub -5 AOs since 1950 were only these: -2/10-11/2021 (-5.285 on 2/10) (weak +PNA, MJO strong 7) -2/14/2010 (-5.132) (moderate +PNA, MJO moderate 8) -2/6-7/2010 (-5.205 on 2/6) (strong +PNA, MJO moderate 7) -2/5-6/1978 (-5.291 on 2/5, lowest Feb AO on record) (strong +PNA, MJO strong 7) -2/13-16/1969 (-5.282 on 2/13)(neutral PNA, MJO unknown) At the same time the PNA could be nearing +1: At same time, MJO could be in moderate phase 8:

12Z Euro for day 9: kuchera 24 hour snow (fwiw since day 9) ZR for day 9 (excludes the ZR in NW NC/VA):

12Z GFS: total ZR through day 10: -much of this is not til day 9-10 and thus still pretty far out and therefore very highly subject to major changes obviously -some of this over especially NW NC, far N NC, and in VA is from earlier storms….see 2nd image: This 2nd image is only for earlier storms. But that still means the first image’s heavy amounts in much of Triad to Charlotte area to upstate SC to NE GA are all from the day 9-10 storm.

I’ve seen in ATL bad icestorms where the temp was mainly 30-31. Not really bad on roads at those temps but bad on elevated surfaces. Especially if the ZR wasn’t pouring and winds were on lighter side. So many variables I guess. Tony @dsaurtold the forum many times about the terrible Jan 1973 icestorm in Buckhead portion of N ATL. He said the temp was mainly 31-32 in that one and the ZR was heavy at times. I think he said roads were bad, too. But there may have been some snow and sleet preceding the ZR contributing to road problems. So, you never know. How far temp aloft gets above 32 is important variable.

2024-5 has a good chance to end up with the strongest +PNA for a non-El Nino winter since at least 1949-50. Edit: Current highest +PNA DJFs back to 1949-50 are El Niño winters of 1976-7 and 2015-6. It actually isn’t out of the realm of realistic possibilities for 2024-5 to even exceed those and become the new highest!

The GEFS mean is forecasting AO gets down to ~-4.5 on Feb 14-15: that’s pretty impressive Edit: This would mean the strongest period of +PNA within Feb since 2017 and potentially a top 5 +PNA for all of Feb back to 1950; also, 2024-5 has a good shot to end up the most +PNA DJF for a non-Nino since at least 1949-50:

What a sharp wedge front! At noon it was 48 at Monck’s Corner 25 miles N of CHS, 56 at CHS, and 76 at Beaufort MCAS, which is 50 mi SW of CHS! At ~1PM it was 80 at Hunter, 78.9 here, and 78 at KSAV! So, winter in CHS area while mid spring holds on in SAV area for no more than a couple more hours. The short term/mesoscale models missed pretty badly the extent of the warmth preceding the wedge front Beaufort to SAV. NAMs/WRFs were awful HRRR was a bit closer. 2:20PM update: wedge front came through, winds increased/shifted, and temps fell 9F here within just a short period. But at 2PM it was still 80 at Hunter and up to 79 at KSAV. Edit: KSAV ended up with another 80+ high with 80, 7th 80+ in 11 days! This one was not at all predicted as only mid 70s had been expected. At 2PM it was 79 at KSAV. At 7PM it was all the way down to 53!

The new Euro Weeklies for 2/24-3/2 are cooler with a stronger signal for a +PNA. There’s also a hint for a Gulf Miller A. No, this isn’t Jan all over again but it is a hint there may be a tamer version and at the very least the idea that winter isn’t over:

Today’s Euro Weeklies for 2/10-16 has the largest area yet of 5”++ (its common to have largest anomalies in an ensemble mean when forecast lead time is shorter):

After a Feb 1-15 dominated at H5 by a strong SE ridge (common in Feb La Niña), the 12Z and other recent GEFS/EPS have more of a mix with a lean toward more days BN than AN at H5 in the SE for the remainder of the month. So, look for more freezes, probably including some hard well inland, in most of the SE on some days within 2/16-28. No we’re not headed back to the persistent strong cold of the amazing Jan. But we’re likely headed back to much more normal for winter. It’s been like mid spring in much of the SE so far this month! Furthermore, much of NC is headed toward a preview of that this week thanks to cold wedging.

From WxBell/JB: The 2025 Hurricane Season February 7, 2025 The 2025 Hurricane Season should have fewer impacts than 2024. 2018 is the closest analog. Unlike last year, there are currently no clear landfall signals. The high-impact forecast area map will be issued with the April update. An El Niño may develop but likely won't be a huge factor if it does. Forecast according to the Power & Impact Scale Named Storms: 15-19 ( Saffir Simpson, same) Category 1 or greater hurricanes: 7-9 ( Saffir Simpson, same) Category 2.5 (start of Power & Impact major hurricane classification): 3 Saffir-Simpson Hurricane Wind Scale Forecast Named Storms: 15-19 Total Hurricanes: 7-9 Major Hurricanes: 2-3 ACE Index: 120-150 Impact Forecast and this is what I am most concerned with, the number game above is window dresing Tropical Storm Conditions: 5-7. Total Hurricanes: 3-4 Major Hurricanes: 1-2 Commentary The forecast is based on the overall cooling of SSTs in the Atlantic and forecasted warming in the ENSOareas of the Pacific. Even now, the Main Development Region is much cooler than last year at this time. I believe the Euro has the right idea on the ENSO region, which is the opposite of last year when the strong El Niño collapsed. This year, the Euro is forecasting a weak La Niña reversing to an El Niño by the hurricane season.

-KSAV today hit 81. That makes 80+ for 6 of the last 10 days! We’re probably headed to warmest 1st half of Feb since at least way back in 1957! -There will be 2 more shots at 80+ this week (Wed and Thu). Then hopefully no more for awhile. It’s been like mid April for most of the last 10 days here!