GaWx

One of the best ways to learn imo is to study wx maps of storms of the past as well as station data and indices (like MJO, PNA, AO, NAO, EPO) to get a good idea for each person’s area. The study of climo is fascinating to me. It takes time but is worthwhile if you have enough spare time.

Aren’t you still getting multiple inches on all models?

This storm will occur during a rapidly retreating -AO toward neutral (4-5 days after a sub -5), a +PNA, a retreating -NAO moving to neutral, and a weak to moderate MJO phase 8.

12Z Euro 24 hour qpf:

12Z Euro: Big hit RDU kuchera 7.9”

Thanks, Brick. For Fayetteville, that 2.9” is really mainly 0.7” of ZR/icestorm with 850s +3+ and sfc temps starting near 32 and falling to high 20s.

UK snow map: 5-6” N Wake at 10:1 (further south not accurate especially well south because counts all wintry precip as snow) https://www.pivotalweather.com/model.php?m=ukmo_global&p=sn10_024h-imp&rh=2025021612&fh=93&r=us_ma&dpdt=&mc=

12Z UK: slightly colder vs 0Z with RDU area near snow/sleet line vs almost all sleet on 0Z early. Thus, the snow maps on Pivotal for N Wake county should be pretty accurate this time for 10:1. S Wake: not quite as accurate

The 12Z GFS and CMC have a pretty close call for wintry precip in the deep SE on Feb 24th from a coastal: GFS: CMC:

12Z CMC qpf: RDU 0.5-0.6” all wintry is a major winter storm there; it is mainly a major snow as Brick showed sleet: a lot parts of E NC

0.5-0.6” qpf for RDU as shown on the 12Z GFS would be a major winter storm for them since all is wintry precip (all with temps well below 32)

12Z GFS qpf

If RDU-GSO end up getting 3-6” of snow/sleet from this, it would be near a historic high for those cities for the last half of Feb during La Niña. It’s important to look at history to keep it in perspective. 6” would be a new record for this category: RDU La Niña 4”+ snows Feb 15-28: 2/16/1996: 5.6” 2/23-4/1989: 4.2” 2/17-8/1989: 4.9” 2/25/1894: 5.0” GSO had 5.7” just after Feb (3/1-2/2009). Furthermore, if a lot of the 3-6” is sleet, that’s much more impactful. Most of these weren’t majority sleet.

Wave #2 (2/22-23) on 0Z EPS:

EPS 10:1:

UK comparison of 0Z vs 12Z at RDU: 12Z UK RDU qpf 1.5”. Of this ~0.1” is snow, ~0.1” is sleet, ~1.1” is ZR (ouch), and 0.2” is rain. 0Z UK is colder than 12Z. RDU qpf 1.0”. Of this, ~0.05” is snow, ~0.75” is sleet, and ~0.2” is ZR. So, much more sleet and way less ZR due to colder aloft.

0Z Euro huge snow hit for many: Kuchera (WB Kuchera Euro are pretty accurate) Sleet underdone on WB Euro: ZR overdone on WB euro:

The 7.6” of RDU “snow” on this Pivotal snow map is way off. Pivotal UK snow maps are typically way overdone on the S side due to counting all wintry as snow. RDU gets a lot of qpf (1.0”) but it is mainly from sleet as ~0.75” falls with 850s +1 to +2. There’s ~0.2” falling as ZR when 850s/925s warm above that. There’s ~0.05” falling as snow. So, 0.75” qpf as sleet is ~2.25” of sleet. Add 0.5” of snow to get 2.75” of an overall dense accumulation….it wouldn’t go anywhere fast! It would have the staying power of 7.6” or more of snow. I had that much sleet here in Jan. It was awesome! @wncsnow knows about the problems with Pivotal UK snow maps

Agree 100%! A 4-6” late Feb storm in La Niña at RDU would be a rarity. RDU La Niña 4”+ snows Feb 15-28: 2/16/1996: 5.6” 2/23-4/1989: 4.2” 2/17-8/1989: 4.9” 2/25/1894: 5.0” GSO had 5.7” just after Feb (3/1-2/2009).

0Z GFS:

Plus it has a 1060 mb high.

The week 2/19-25 has a good chance to end up the coldest week of the winter at GSO (and at other NC cities). If so, it would be the latest coldest week there since way back in 1993! Then the coldest was 3/13-19/1993 due to the superstorm. Going back to 1959-60, the only two other winters with a later coldest week were 2/21-27/1967 and 3/4-10/1960.

The new Euro Weeklies for 2/17-23 is the coldest yet for that week in the SE. In terms of anomalies, this would be the coldest of the winter in most of NC if it were to verify. In terms of absolutes, it would be close to Jan 20-26 for coldest in much of NC. For S GA/SC, it would be either 2nd or 3rd coldest in terms of anomalies/3rd coldest in terms of absolutes. For N GA/upstate SC, it would be ~a tie with Jan 20-26 for coldest anomaly and would be 2nd or 3rd coldest in terms of absolutes:

In addition to 2/13-14/1960, it appears that the terrible 2/2/1996 icestorm was from a Miller A. I don’t even see a wedge! https://products.climate.ncsu.edu/weather/winter/event/?e=159 At the time it was the worst ever in Hickory and Statesville for outages: “By 1500 EST, many major population centers such as Hickory and Statesville were reporting 50 percent power outages. The storm became the "worst ice storm ever" in local power company records. By late night most customers had lost power. Many customers did not have power restored for up to a week during extremely cold weather.” @StantonParkHoya