Carvers Gap

You can see the increase in snowfall from 6z to 12z for the GEFS. That is quite the storm if it verifies.

It could, but that low placement is well west of other guidance. That is definitely a downlsope. But it is important to remember that modeling is just now dialing this in. If that low were to deepen, that precip makes it across the mountains. Also, people west of 81 and 75 would likely be in the game. I rarely get downsloped here from a SE wind. It is a legit concern in the foothills unless the slp strengthens. I get downsloped when the system approaches from the west of Kingsport. With models moving around so much, doubt they are done.

To me the track is fairly consistent now. What is unknown is how much of a handoff will occur, ie how much of the remnant original low sneaks west of the Apps. Models differ greatly. In general, we have seen modeling trend well south today. Now that the track seems almost consolidated, let's see what happens. Modeling may stay with the same look or it may strengthen the slp in the coastal plain as the upstream unknown variables are solved. Definitely could bust, but a good run of the GFS for most of the state. If the Euro holds at 12z, that is a good look.

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.