Carvers Gap

Downlsoping could be a problem east of I-81. I think west 81, it would be less of an issue. Now, when it pass through initially, downslope could be a problem. SE return flow the west side of 81 benefits most of the time.

Yep. So you can compare the trend from 6z to 12z. Generally what I do.

Looks very much like the Euro.

The 12z GFS was just a massive snowstorm for TN. Surprised nobody has posted the maps. The GFS cave is almost complete....The Euro, if it holds and its track verifies, it retakes king of the hill status.

How big is the area for the regional average? TRI has already been in the teens 4x this month w/ an average low of 27 to date, and that includes two really warm days to start(out of 12 days)....I would think(no guarantees) that the timeframe after the 20th potentially could yield some pretty low numbers here. We have already hit 15 and 16 with just light snow cover. Edit: To define "pretty low," maybe low teens or slightly lower. That looks like a really cold air mass. If any storm to our east deepens, TRI can get pretty cold with those. Potential is there for lower with a big system. In 17-18, our rivers froze with no snowfall on the ground.

Auburn, with that big transfer from UNC, is Final Four caliber.

So this has trend so much south since last night that the risk is a whiff to the south. LOL. The GFS is either about to score a coup or has a big problem with old school NAM type amping.

And turn out the lights in the rest of the Valley - major ice storm.

Only issue is that is a weak, weak system being portrayed - speaking of mb. The downslope in E TN would be a big problem unless it starts to spin-up a bit better. Need rates to overcome the downslope. Chattanooga peeps say, "Bring me the NAM!!!" LOL

That is a HUGE move by the NAM. Looks like a Miller A if it doesn't slide off.

That NAM run is coming in so far south, it actually is bringing Chattanooga into play and whiffing above I40. Now let's see if it makes the turn or slides OTS.

That is so far south at 65, it doesn't even look like the same storm. LOL.

This is a fairly sizable change by the 12 NAM through 60. It is the NAM at range so that could be the case....

Looks colder across the forum area.

Greene is crazy. Used to have a poster over that way who posted a bunch @waltrip. Think @Math/Metis over there as well...or at least follows the wind situation at Camp Creek. Micro-climates galore in Greene Co.

Auburn is good. Don't even get me started about how the SEC pretty much forced UT to fire Pearl only to let him come back to Auburn after his show cause was over. So crooked. UT is feast or famine during games. Long scoring droughts and poor line-up rotations have kept us from winning some games. ZZ, Vescovi, and Chandler are the three we need getting time together, and consequently, the most minutes. We don't have a dominant post game, so we are going to have to be slashers, drivers, and push the tempo. They will need to rotate those guys around on defense so that they can manage their foul situations. We are missing some pieces right now in the post, or this team could go deep. Without consistent post play, our results will look similar to the LSU game.

Unless Arctic air is in place....pretty much the case at this latitude. GOM and mountains just add an extra degree of difficulty.

The 0z EPS control run wins the award for coldest run of the year. TRI barely makes it above zero on this particular run for this particular day. Temps the next night(after this hour) over the TRI region drop to -10 to -15F. Those temps would push for record lows. Now, this is just one map, but it does exemplify what can happen with so much cold waiting in the wings and a 500 pattern which supports it. Models are showing some hints of the colder pattern breaking down right at the end of the month, but could be a cold couple of weeks getting to that point. The ensemble snow runs are pretty massive.

Problem is that we don't have a ton of fresh, cold air in place. Really depending more on the track. This system has been on modeling since almost day 16(?). This is the beginning of a cold cycle within this pattern which is why. Normally(and this depends on where one live...but will use the eastern valley as an example), a track from New Orleans/Mobile into South Georgia to inside Hatteras...that is the money track. That is called an inland runner. The closer that gets to the coast, the more difficult it is to get precip to come over the mountains. The close that track gets to us(unless cold air is in place already), the more mixing becomes a problem - see the last two storms for that reference. Also depends on the strength of the system. Stronger - need it on the outside of the best track envelop. Weaker - need it closer like running along inside edge of the coastal plain. Middle TN actually benefits from a track through E TN or along the spine of the Apps or W NC. The exciting thing about the pattern after this, plenty of cold in reserve.

Downsloping could/will be an issue. Thing is, if the slp placement is wrong on the GFS....it should be less. My concern is that this starts as rain north of I-40, and the surface cools due to evaporation cooling (overnight onset). That could creat an ice situation on the west side of the eastern valley as cold air gets banked against the Cumberlands.

I am still not bought-in on this storm yet. Too many good forecasters say to be wary, but the 0z NAM was used by MRX to mention a non wintry solution. 6z changed. I am glad I am not in their shoes. This comparison is in no way a criticism of them as it came out AFTER their morning disco. Normally, I wouldn't use the NAM at range, but since it was mentioned in a disco, thought it was worth a look. The single frame is the end of the 12k 6z NAM. The double frame is a comparison of the last two runs. The 6z NAM is pretty much the same as the 6z Euro.

6z NAM went with the Euro.

Through 75 on the 6z Euro, definitely a jog south.

The 6z Euro through 72 is south with its precip shield through 72 which fits trends from overnight. We will see where it goes.

I normally wouldn't use the NAM at range, but that is a major winter storm on 6z - ice, sleet, snow. I got up this AM, and was expecting the "poof" deal. Just looking at modeling, this is a significant winter storm north of I-40. I The NAM actually keeps the primary slp along the GOM. I do think the warm nose is going to be a problem, especially in the eastern valley. So, my expectations are low...but this looks like a mess IMBY. Let's take a minute and look at timing. In the eastern valley, the GFS warm nose moves through in the very early morning ours while it is dark. I can tell you from experience, that brings all kinds of headaches. The low passes to our southeast during the morning hours Sunday. The Euro is slightly slower. One would think the Euro would have more mixing issues....but it has less. The 6z Euro is rolling. Colder through 63.