John1122

That, I don't know. I've never thought that time frames would make a difference, but that's possible. I'm trying to remember what resolution the GFS runs at now. The Euro is 9k, the ICON 13.

To me, the ICON is the middle ground between the Euro and GFS. The Euro is dry, the GFS loaded. The ICON is close to the middle. RGEM is as well. That's discounting the oddball NAM runs for now.

GFS was fantastic.

It's actually a pretty decent model for these set ups. It's got a higher resolution than the GFS at 13k, not dissimilar to the NAM 12k

I just generally have very little faith in the NAM beyond 24 hours, even less so when it's throwing out something pretty wild that no other model is showing. In the end, they basically have until around 7pm tonight to make a decision, as that is 12 hours before they think this starts in Chattanooga. I'd expect they'll make a decision after the 12z runs come in.

The biggest thing to me is, even those are massively impactful winter storms because they have so much freezing rain/sleet/snow. It's a winter storm for most regardless. Heck, they even said my area was basically good for 4-6 inches regardless and didn't put the warning out here.

They generally only ever use the American models and the Euro. Never really the Canadian/ICON etc.

ICON was a better version of the RGEM. So far it's HRRR/RGEM/ICON vs NAM 12k/NAM 3k.

ICON looks fairly similar to the RGEM so far.

RGEM ended slightly better than 0z. Much better thermals and no crazy secondary low traveling from Alabama to WVA.

RGEM cold, but dryish so far. To get the juice of the NAM, you have to have the insane secondary low that develops and is a plateau runner (literally never even seen that before in all my years of model viewing)

12z Euro Ai Copy/Paste of every run the last 5 days. .4 to .7 QPF, area wide sub-freezing temps and 850s.

06z suite so far. HRRR almost no freezing rain, issues along the GA border in the East. Everyone from the Plateau/Eastern Rim gets some totals cut by sleet. SE areas are dry slotted and have less QPF overall. Even with the sleet 40 and north gets 5-8 inches with N Miss and N Bama doing well in the mid and west areas. 12k NAM a slightly worse version of the HRRR. Big time ZR in the central valley of East Tennessee 3k NAM all the problems of the 12k but magnified. Big dry slot, mixing issues for all. East of 75, especially east of 81 and south of 40 in Eastern areas aren't great. 1-2 inches of snow. .15 to .25 freezing rain in those areas. ZR is an issue south of 40 all the way to Nashville. But Plateau and West still manage 3-6 inches of snow.

It's frustrating, for sure. The 12k NAM is super QPF heavy for everyone almost. 1 inch of precip in Knox, about .5 is snow, .3 is freezing rain, .2 is sleet and there's a little rain in there too.

The HRRR is much better than the NAM 12/3k. Didn't help the counties in the far SE/E but was better for everyone else than either NAM.

Titanic dry slot on the NAM 3k. Mixing. Mountain rain issues etc. The works basically. All the hi-res American models are having those issues now. 3k is bad for anywhere in East Tennessee, especially so East of 81 or south of 40.

03z RAP is amped with the Apps low. SE/Polk gets screwed but it's way out at range so I don't expect it to be great.

EURO sucked for me that run, but no mixing issues once again for Tennessee. It's on the weak edge still of all the models.

UKIE around the same qpf, all snow in Tennessee.

Canadian. I think it went up around an inch or 1.5 in areas along 40.

7 inches here, it was an epic front end thump that switched to rain and 33 degrees.

GFS was basically a reprint of 18z. Maybe more snow around Knoxville. Heavy sleet in Chattanooga but several inches of snow falls there too.

December of 81 was a good bit colder and had a big snow just before Christmas. It was dry, about 60 percent of normal precip.

18z AI Euro just finished a bit ago. QPF up, no mixing/amping issues.