Carvers Gap

Yeah, he is about to post a dub for his seasonal forecast...went against most seasonals w/ a strong analog package and called the late January/early Feb storm track back in Oct/Nov. Just so I don't have to post twice(not that it stops me! LOL), here is where the 12z AIFS ends up. Weak comma head w/ a deepening coastal. I bet the 96 system looked a lot like this. I noticed that the flow backed a bit at the end of that first storm.

Think it was its usual bias of holding back energy?

And this would be the concern. Winter storm w/ ice followed by this...

Just an aside...the Euro Weeklies keep winter ongoing through Feb w/ a break between maybe Feb2-7th. Cosgrove said last night that the pattern may not break fully until the first week of March.

The @AMZ8990ice storm....this looks like it could be a redux of that bad storm you all had. Just not sure about E TN yet. What year was that, @AMZ8990? Temps were in the teens while freezing rain and sleet were falling.

As I have stated prior, the Jan 96 snows were wild. Knoxville would get lots of ice/snow. TRI just got slammed w/ heavy snow. It was wild driving home. @Holston_River_Ramblerand I were talking about that in this thread. I would see 4-5" of snow until around mile marker ~45 on I81. Then, it just started getting deeper. Knoxville's roads that winter were terrible. Knox Co ran out of snow days by quite a bit. I would guess areas of TRI got 30-40" of snow with those two storms. I will add...this gradient is most assuredly going to wobble north/south on modeling, and maybe right up to the event. Very tough to nail that down boundary. Cold has been over-modeled recently. I would guess the southern solutions do not verify. I would also guess someone in this forum is going to have frozen precip falling into temps which are in the teens...west TN would be my first pick. E TN is a toss-up, but ensembles really like snow/ice in E TN as well.

Yep. Legit scenario. With the 1040+ hp over the top...that gives me a bit more hope than normal for snow. But.... Very concerned about ice w/ that scenario. Textbook ice setup, and models wouldn't catch that until it was under way IMHO. That high would keep funneling low level cold down the valley as rain goes over the top...and up the valley. Basically(and I know you know this...but kicking around the idea), the cold wraps clockwise around an incoming hp over the western Mid-West. Then, the cold hits the Apps and funnels south. The scenarios where we get snow...cold is right over the top. The scenarios w/ the warm nose...the cold lags. But with both scenarios...the cold eventually catches up. The Euro AIFS EPS was very bullish on snow w/ many members as snow. I am leaning towards cold winning the day, but am not sold on it. So, I definitely like hearing the other side of the coin.

Day 6-10 CPC analogs: 20240118 20030123 20110113 20210210 20070207 19960202 20030114 20140208 20100130 20170204 Day 8-14 CPC analogs: 20030125 20160211 20160117 20100215 19950205 20030112 20070213 19950128 19960211 20060209

Back in the days of the NOGAPS and CPC being our only internet wx sources....you just had to use your imagination.

Agree for sure. The only thing that gives me pause is this past week looked great...and it went poof quickly. I would say I am cautiously optimistic for a winter storm....but ice is no bueno IMBY. And maybe these extra flights are helping some...IDK.

With the notable exception of the GDPS para(I called it the GEM para...same), most deterministic runs of this event have precip falling into temps which range from the low teens to lower 20s. The GEM para has temps in E TN only in the mid 30s, even w/ downlsope/warm nose/ etc. The 12z EPS manages to get cold air in place prior to the event. The 12z GEFS has a bit of a warm nose, but as soon as precip starts...the front crashes into the STJ. The GEPS is somewhere in between. Ensemble temps are mid20s to mid30s. The key will be getting a big high over the top(1040s are good) which feeds the north side of any potential STJ pulse.

The 12z EPS(normally very conservative and known as the ultimate Dr No) has this...big high over the top and active STJ. Definitely an eye opener from an ensemble at 150. By Tuesday evening, short range models should have this. Some streamers on the EPS arrive on Friday and the last does not depart E TN until Monday.

I think the 12z GEM para is very plausible as well and fits recent Nina climatology like a glove. This would be the northern side of modeling so far.

Definitely don't want to lose power with a potential Arctic front barreling down the Plains a few days later. I am sure the NWS will give this about 48 hours for modeling to get this into focus...and then put out the word. Still a lot of uncertainty right now.

I think initially, we want it suppressed at this range. The cold which pushes after this could be strong. I want to get this within about four days. I could still see this really surging warmth into the TN Valley if something cuts. I can definitely see a scenario where something cuts, draws cold down, and the second wave is snow/ice. But the slider scenario is plausible. For whatever reason, modeling this winter has found a way to be universally wrong from suite to suite. So, I expect a jog north...well north of the GFS as nearly all of the GEFS members are north of the deterministic. But the 12z GFS deterministic is almost to a range it can be trusted, but not quite yet. Fun discussion, but those tracks are gonna move some at this range for sure. I don't want ice either. Ensemble packages look good though at 12z.

My only caveat would be that modeling has struggled this winter. Right now though, this is at day 4-5 for far western areas of this forum. By tomorrow evening or Tuesday morning, short range models should begin to have this for portions of Arkansas.

If this actually occurs, the EURO AIFS and its ensembles had this days before other modeling did......

The 12z EPS has temps thirty degrees BN (over TRI and E TN...cold over the entire forum area and EC) from ten days out which is almost unheard of from that model. Again, I have my doubts, but just reporting what I see. The winter which shall not be named as an analog....is trying to sneak into the photo.

The 12z Euro ensemble individuals show strong support for the deterministic run.

It is again worth noting that wx models have done a much better job of identifying cold fronts during the last few weeks, but they have been over-doing cold almost across the board.

Just grabbing some maps. The temps are also a big story. Modeling is still picking up a sharp cold shot right around 300 which is after the rain/snow/ice/sleet we are looking at. Some of the seven day temp departures, undoubtedly enhanced by potential snow cover, are impressive. I also added the accumulation maps for the Euro run.

Yeah, man. We want none of that. The cold air looks vey likely. The wild card is whether the STJ gets its act together. We have seen "false positives" this winter with it. Like I said above though, this event is within five days for folks in Arkansas...and almost four.

The concern, and we have talked about this for at least a week...is that this potential cold air mass will form a gradient boundary which presses west to east. The cold air will submarine under warm air, and that creates the conditions needed for ice. We dodged one window this past week as the STJ didn't attack the base of the trough. The STJ looks to show some life right now at the worst possible time - and you all know I like winter, but not ice. Again, a lot will change and that should be noted in all caps. But it sure looks increasingly likely that somewhere between Birmingham and Lexington is gonna see a winter storm and maybe a bad one.

The 12z GEFS has at the first round of light mix into west TN by early Friday....and waves of rain, sleet, snow, and ice persist until the following Sunday - like ten days of waves along the gradient. No idea if it is right. I am just the messenger on this.

The ice amounts from the 12z Euro are pretty staggering. I want NONE of that - nada, zip, zero. Here are the 12z deterministic runs for next weekend. Things are going to change with this almost assuredly. Keep in mind though, Arkansas has this storm within five days now. Also, the frames below are only snapshots. The GEM frame is the second wave. Most models had a couple of waves.