GaWx

The SE portion of UK snowfall maps on Pivotal, just like the Icon snow maps on Tropical Tidbits, are beyond awful because they’re often way overdone. This map is likely counting much of the ZR as 10:1 snow.

I disagree. The Euro AI has been awful. For example, check out these insane snowfall amounts (and the model really had it as snow with 850s <0C):

0Z Euro: major snow far N GA/W NC/NC NC/VA and ice, ice, baby many of SE VA/NC big cities into N SC:

That would likely be the biggest winter storm in that area in La Niña in Feb since 1989.

Tony stuff: ZR:

0Z CMC: ice, ice, baby and Tony sleetstorm NC:

0Z CMC setting up to come in more suppressed/colder than 0Z GFS. Let’s see.

0Z GFS: Based on maps through hour 93, my guess is that this will unfortunately look more like the 12Z than the 18Z. We’ll see. I hope my guess is wrong. Edit: Indeed, I don’t think the 0Z GFS will be liked.

Way better run than yesterday’s 0Z, which had virtually no snow in NC/SC/GA but not nearly as good as 12Z especially in NW SC, N GA, and SW NC. So, an in betweener.

Thanks, Chuck. Why is there a discrepancy between your map and the CPC? The graph below shows all days within 1/15-2/11 to be either +PNA (1/15-17 and 2/6-11) or neutral (1/18-2/5). So, 9 days +PNA and 19 days neutral meaning a mean of weak +PNA.

Regardless of Mar, in the meantime some of the best climo of the winter is in the last half of Feb. We still have another 2 weeks before March. Granted, it isn’t normally as good when it is La Niña. El Niño has the best Feb climo as we know. However, the pattern is anything but Ninaish with the -5 AO about to hit along with a rising +PNA to a strong one (combo typically has lingering effects). Will there be a NW trend like is common and occurred for the 1/10-11 storm? Or will there not be one like was the case for the 1/21-2 storm? We’ll see! So far there’s no indication of an impending NW trend, which may be partially related to the rare very strong -AO.

Barney says hey to E NC: holy snowcover but very likely way overdone: single digits at 1PM? No, Barney, you’re being silly! GFS has a strong cold bias over fresh snowcover. Nothing new.

18Z GFS: Barney doing his cold thing at 2m and 850 mb. Preliminary maps showing the low over MX in combo with the cold may mean more suppressed than 12Z.

That doesn’t mean dry. It means drier than climo avg. for 2/17-23. For Marietta, it still is giving 0.70” (not dry at all but drier than climo avg of 1.1”).

Asheville is +9 for Feb 1-12. The forecast per the 12Z EPS mean (which is between the less cold GEFS and the typically colder GEPS) is for -7 the rest of the month. If the EPS mean verifies well, Asheville will end Feb very near average. I admit that the 12Z EPS mean may be overdoing the length of the BN to some extent. But fwiw, it literally has Asheville BN on Feb 14 and then the 12 day period Feb 17-28 implying high chances for a significantly longer than 4-5 day period BN. Here is the new Euro Weeklies (based on 0Z EPS) for Feb 17-23, coldest yet by a good margin: that’s ~11BN for Asheville. The entire SE other than FL is BN even for mid-Jan: Feb 17-23 qpf: keep in mind that NN or even slightly BN is still pretty wet in mid to late Feb: 0.85-1.5” NW to SE in much of GA/Carolinas (ATL/Charlotte 0.85”; Triad/Triangle 1”, Augusta/CAE/ILM 1.2”; CHS/SAV 1.5”)

The models remain unanimous with a low of sub -5 AO on/near Feb 15th. Below is the latest GEFS. Today (2/13) it was at -3.7, which is actually lower than the -3.25 this chart shows. That gives me extra confidence that it will go sub -5 in 2 days: Sub -5 AOs are pretty rare and have always been accompanied and/or immediately followed by intense cold and/or wintry in parts and often much of the SE. Here are the ones during DJF since 1950: 1. 2/10-11/2021: major ZR GSO 2/12-13 2. 12/18/2010: significant to big snow one week later much of inland SE and light on coast 3. 2/6-7/2010, 2/14/2010: two winter storms (2/5, 2/12-13) affecting most of SE between them including some on coast 2/12-13 4. 1/2-6/2010: light snow N GA/very cold SE 5. 12/20-25/2009: winter storm mainly NC 12/18-19 6. 1/18-20/1985: 1-2 mainly light snows much of inland SE 1/17-20 followed by historic cold 7. 2/5-6/1978: several mainly light snows SE 2/2-9 including some on coast 2/8-9; very cold 8. 1/11-17/1977: snow events almost all of SE during and soon after including Miami and parts of Bahamas 1/19; very cold 9. 12/28-29/1976: several wintry events then into first few days of Jan inland SE; cold 10. 2/13-16/1969: major winter storm 2/15-17 Charlotte to GSP/Asheville; wintry precip most other areas within 2/14-17 including light on coast 11. 1/28/1966: several wintry events 1/25-30 including on coast 1/27 and 1-2 majors much of NC; extreme cold 1/29-31 12. 1/21/1963: extreme cold the week following; several light wintry events inland

The models remain unanimous with a low of sub -5 AO on/near Feb 15th. Below is the latest GEFS. Today (2/13) it was at -3.7, which is actually lower than the -3.25 this chart shows. That gives me extra confidence that it will go sub -5 in 2 days: Sub -5 AOs are pretty rare and have always been accompanied and/or immediately followed by intense cold and/or wintry in parts and often much of the SE. Here are the ones during DJF since 1950: 1. 2/10-11/2021: major ZR GSO 2/12-13 https://climate.ncsu.edu/blog/2021/02/rapid-reaction-back-to-back-ice-storms-pound-the-northern-piedmont/#:~:text=February 12-13 Storm&text=Reports aggregated by the National,weakened ground%2C caused numerous outages. 2. 12/18/2010: significant to big snow one week later much of inland SE and light on coast 3. 2/6-7/2010, 2/14/2010: two winter storms (2/5, 2/12-13) affecting most of SE between them including some on coast 2/12-13 4. 1/2-6/2010: light snow N GA/very cold SE 5. 12/20-25/2009: winter storm mainly NC 12/18-19 6. 1/18-20/1985: 1-2 mainly light snows much of inland SE 1/17-20 followed by historic cold 7. 2/5-6/1978: several mainly light snows SE 2/2-9 including some on coast 2/8-9; very cold 8. 1/11-17/1977: snow events almost all of SE during and soon after including Miami and parts of Bahamas 1/19; very cold 9. 12/28-29/1976: several wintry events then into first few days of Jan inland SE; cold 10. 2/13-16/1969: major winter storm 2/15-17 Charlotte to GSP/Asheville; wintry precip most other areas within 2/14-17 including light on coast 11. 1/28/1966: several wintry events 1/25-30 including on coast 1/27 and 1-2 majors much of NC; extreme cold 1/29-31 12. 1/21/1963: extreme cold the week following; several light wintry events inland

12Z Euro is much better with much further SE track and major winter storm at least NC

12Z CMC looks like it may have two waves. First wave gives NC a mixed bag of SN/IP/ZR.

But almost no snow most of NC fwiw due to it not allowing deep enough cold air to get in there first/too fast with the low. There’s good bit of ZR:

12Z Icon almost all snow for precip type in ATL area with 3-4” of snow from ~0.5” qpf. Would mean ATL area total snow to date of mainly 6-8” from 2-3 measurable snows and biggest snow winter since the similar 2010-1! Before that, one has to go back to 1992-3 for the great March SOTC on northside of ATL (including Sandy Springs/Dunwoody) for about that much snow in a season although less fell in the city south and more fell in Marietta/Cobb. Also, this would mean two major snows (3.5”+) this winter city northward. Last time that happened northside of ATL probably at least back to 1959-60 thanks to March! 1894-5 had two major snows all of ATL area thanks to the great frigid Feb of 1895.

0Z EPS has finally resumed. It does have more snow (10:1) in NC, N SC, and N GA than recent runs:

1. 0Z EPS appears to look better than 12Z although it looks like it is stuck on hour 168 at WB/Pivotal. 2. 18Z Mogreps (UK ensemble) looks pretty good with the offshore track of the low. What a big contrast of that with the 0Z UKMET/Euro ops! Edit: 3. 0Z Mogreps doesn’t look as good as 18Z with mean low track not as far offshore and thus not as cold over the SE.

0Z UKMET is coming in well inland unfortunately for SE snow lovers.