GaWx

The Weeklies clearly moderated over the weekend vs those with a stronger cold signal late last week. Also, there are some signs of can kicking of the start of the good pattern.

Here's the 0Z ICON clown, which I'd obviously love to verify with its 3" of snow imby (would be biggest snow since Dec of 1989) but am not at all buying now considering how much warmer are the GFS/Euro suites, the general inferiority of this model vs those, how much colder this run is vs yesterday's 12Z ICON, it still being out a week, and the extreme rarity of snows like this here:

The 6Z EPS continues the 0Z Euro suite trend toward a further NE trough/less cold air available for this storm.

OTOH I just saw that the 0Z ICON was much colder than its 12Z run along with some snow and similar to the cold 18Z and prior GFS runs. (For whatever reason, the extended portion didn’t come out until much later.) This is very much a fwiw and I‘m not buying it considering the trend of the 0Z Euro and 0Z/6Z GFS suites, which will need to reverse course to revive any significant non-mountain SE wintry prospects from this storm.

The idea of there being much less cold air to the north in advance of any storm on the 0Z GFS suite was also on the 0Z Euro suite vs its 12Z run as well as on the 6Z GFS suite. Not a good trend on these last two GFS suites or the 0Z Euro suite for SE wintry prospects as they’re too warm. They’re going to need to reverse course or else that would be all she wrote for SE wintry prospects from this system.

The further north track and warming from recent GEFS runs to the 0Z GEFS is similar to the 0Z op GFS. The source of cold to the north in advance is much warmer than in recent runs.

Feb is setting up to be quite an interesting month this year in the SE as it often is during El Niño. Some and possibly many will ultimately be disappointed but hopefully many will instead be pleased. Regardless, the forecasting discussion threads should be quite interesting and busy as we speculate on possibilities!

Now look how low the OHC is: ~+0.25

Fixed your post.

-23, -22

Take it with a grain/don’t trust it, but fwiw the new Euro Weeklies run is easily the coldest overall yet for mid Feb through early Mar. Once the BN temperatures set in Feb 12-19, they remain through the end of the run (Mar 4-11). The week of Feb 19-26 is by far the coldest for that week of any run yet and may, when also considering El Niño climo, have the most winter storm potential in the SE of any single week per this run with Miller A/GOM potential written all over it (combo of Aleutian Low/+PNA, -NAO, -AO, and moist subtropical flow/split flow):

Indeed, we may. I had thought these last 3 days were going to be more negative than they ended up being. It may be close.

Not in the least bit. This is purely for fun, bragging rights, and contest purposes. It will be in the record. Don’t forget that we have a contest in another thread. Edit: In light of the next post, I want to restate that this would make a difference between strong and super on an UNROUNDED basis, which I go by since we have the unrounded available. I call +1.50 to +1.99 strong and +2.00+ super-strong. For those going by rounded (i.e., what shows in the well-known table), it will be quite difficult for it not to end up at +2.0 unless the ERSST/OISST relationship were to be far different in Jan vs the Aug-Dec average.

The 12Z GEFS starts to establish a strong Aleutian Low toward the end of the run (Feb 10-11), which would be right on schedule with regard to the longer term long modeled more favorable pattern getting established for mid to late month. I’m not trusting it but I’d rather see it than not. So far, no can kicking…fingers crossed.

The 12Z GEFS run suggests a good chance for no more widespread multiple day warmth for quite awhile in the bulk of the SE (including NC/VA lol) after this weekend. We’ll see though as ensemble means smooth out extremes due to timing differences. It wouldn’t surprise me if there are still a couple of warm ones sneaking in during Feb 1-10 before the hoped change to more sustained BN soon after.

-Jan 1-25 has averaged +1.86 on the cyclonicwx.com’s OISST. -The Nov and Dec ERSST combined averaged +2.045. That means that Jan ERSST needs to average +1.90+ to end up with a +2.00+ NDJ ONI (super Nino). -ERSST averaged 0.08 warmer than OISST Aug-Dec. -If I assume that ERSST/OISST relationship were to hold in Jan, that would mean that the Jan OISST would only need to average +1.82+ to end up with a +2.00+ NDJ ONI. Compare that to the +1.86 for Jan 1-25. -What is needed during Jan 26-31 to bring the full Jan OISST down to +1.81 or lower? That would require Jan 26-31 OISST to be cooler than ~+1.65, perhaps near +1.62. -The last week has averaged only ~+1.625 with yesterday’s +1.59 being the coolest in months. -If Jan 26-31 were to rise back to an average of +1.65, a pretty difficult task as of now, the Jan OISST would end up at +1.82. Under the assumption of the Jan ERSST being 0.08 warmer than OISST, that would mean a NDJ ONI right at +2.00 (super). But if Jan 26-31 OISST were to instead average only +1.60 (near where it is now), Jan OISST would end up at +1.81 and NDJ ONI would end up at +1.99 (a hair cooler than super). -So, it is literally down to the wire. These next 6 days could be crucial! Of course, if the ERSST/OISST relationship for Jan were to change much from the 0.08 difference of the prior 5 months, that could change things, too.

Indeed, at this link, DT’s quite different: https://wxrisk.com/operational-weather-forecasts/ The Middle Atlantic Operational Forecast includes coverage for the next two weeks. It is an all-purpose forecast that covers: West Virginia North Carolina Virginia Maryland Delaware

DT actually includes all of NC as Mid-Atlantic. For example, Charlotte is included. Also, I didn’t know that WPC includes NC in it. What a difference in what they consider SE vs what the SE includes here.

I just went to DT’s site and sure enough I see he has NC in what he calls the Mid Atlantic region. So, NC can now relax since he’s including it for wintry potential lol. He has DE as the most N state in the M.A. and excludes NJ, PA, and NY, which are normally included. I’ll just say that his definition of M.A. is highly unusual in that it is centered much further S than in any other case I’ve seen it used.

But our SE subforum of AmericanWx has not only NC but also VA. So, even VA is included in many other cases as SE, not mid Atlantic. Some do count VA as being in the southern Mid Atlantic. If DT’s considering NC as S Mid Atlantic, he’s off imo. The link below has VA in pink, which it is calling S Mid Atlantic: https://en.m.wikipedia.org/wiki/Mid-Atlantic_(United_States)

Regarding the bolded, that would just make the already frustrated NC folks that much madder as that’s exactly what happened in the middle of this month. The sanitarium thread would be overwhelmed!

1. Having 2009-10 as just moderate in that isn’t consistent as the ONI peaked at +1.6 and was still +1.5 during DJF. That’s a “strong” peak, not moderate. 2. That also has 1972-3 as only strong despite an ONI peak of +2.1, which means it actually had a “very strong” peak. So again not consistent.

The 12Z GEFS by a good margin has the lowest H5 hts, the coldest 850 mb/2M temperatures, and the heaviest qpf in the SE of any run to date for Feb 4-6. Unlike prior runs, it has many members with an E GOM low that then crosses the FL pen. To clarify, the run isn’t suggesting this would likely be cold enough for wintry precip. as the surface cold air supply is lacking. But it does suggest there’d likely be no warmth around this period if it were to verify. 18Z GEFS is similar to the 12Z

RDU 6 coldest Febs since 1980 were all during El Nino: 2015, 1980, 2010, 1987, 1983, 2007

I realize the 6Z GFS is a cold outlier and thus of course don't buy it, but fwiw it only barely gets RDU to just over 50 only one day after Jan 28. IF it were to somehow verify closely and considering the cold potential of mid to late Feb, the chances for the coldest SE US Feb overall since 2015 would be greatly increased. That was during another El Nino.