Carvers Gap

The 12z RGEM now has the system in range and has healthy bands of snow, rain/snow mix, and rain showers over the eastern half of the forum area - just like the Euro has had run-after-run for days. I am honestly surprised to see the Euro hold after missing so much last season and it being shoulder season.

The 12z CMC now brings the backside energy in the form of heavy snow showers on NW flow...complete cave by it.

Pretty interesting development on the 12z GFS and a fair amount of change. It pops a low over the Piedmont of North Carolina as opposed the northern stream dominate solutions it previously had. If true, the Euro(if it doesn't flip at 12z) has scored a "1 vs everybody" coup.

The November Euro seasonals are in. January looks decent. December could likely be colder than what it depicts, ESPECIALLY if the Euro weeklies from today are correct. Those weeklies look frigid through mid month. Warm Feb-April. But if we get Dec-Jan, we take it an run.

With snow cover in the foothills and higher elevations, most models(not the GFS) have temps 25 to almost 40 degrees below normal on those days.

The Euro is a bit deeper with this. The GFS deterministic is still further north but trending south. Interestingly, the GEFS lockstep with the Euro. Either way, this is a quick cold shot which means business. If the winter remembers what happens in November, we should see this reoccur.

The 12z Euro is leading the way on this 9-10th system. I can't say that gives me a lot of comfort as I have grown to trust the GFS in handling systems a bit better over the SE. I would guess this might amp up as we get closer and IF the system continues to create this type of energy in the lee of the Apps.

During the 70s, 80s, and 90s I rarely saw snow before Christmas. But my parents remember lots of snows in the 60s which were early. It certainly seems that early arriving winters are more normal now with February being less storm - kind of traded one for the other. Just a quick update so I don't have to post twice. The Euro continues to advertise a rather vigorous wave w/ the 9-11th cold shot. The GFS and CMC not so much. The Euro makes the most sense as that is a very common occurrence when cold are arrives which is that strong. Something to continue watching.

We had a forum prior to AmWx. It was basically the people from this site, but closed down. We were in the SE forum then. When we switched, the owners of this site graciously gave us our own forum. There are lots of storm threads in SE forum thread of the other site, even for our area. Eastern Weather I "think" was its name. I do think they archived it, but I am not sure where it is. It would be great to archive our stuff for the TN Valley and make it like a library. I am not sure how proprietary rights would work with that. But at least we would have a backup. Eastern just went off line one day, and never came back. Lost all of it.

The 18z GEFS 500 sigma has it yet again, and is now stronger. Something to watch. I have prob posted too much about it, but these types of systems can be potentially fun to track. Need to get inside of four days to really get a good feel for this. Sometimes northern stream energy will trend northward over time, and the phase is missed. Right now, we want the trend on the GFS operational to be slower and a bit deeper. The GFS being too fast is a bias just as much as the Euro being too slow.

Sure looks like the 18z has held back the energy on this run and sped up the energy flowing underneath. It probably won't get to 12z Euro levels, but that is a big step at 500.

@Mr Bob, @PowellVolzis locked out of his account again. If you can give him a hand, it would be hugely appreciated by Powell. Thank you!

MRX from this afternoon.... Ridging builds back in Thursday afternoon with warmer temperatures and quasi-zonal flow in the mid and upper levels of the atmosphere.. A more progressive trough will approach the Mississippi Valley by late Friday with an associated surface low pressure near the Great Lakes. A cold front will move eastward across the forecast area Friday night into Saturday morning with widespread showers and thunderstorms expected. A few rounds of shortwaves will strengthen the upper-level trough across the region Sunday night into Monday. Deterministic and ensemble members are in good agreement even this far out from the weekend. The LREF indicates about a 70+ percent chances of temperatures less than 32 degrees across the valley next Monday night, which is a fairly strong signal this far out for a widespread freeze. With northwest orographic flow and 850mb temperatures below 0C, some light snowfall will be possible for higher elevations above 4000 ft across the mountains. A significant return of cold air appears likely early to mid next week bringing an early taste of winter.

Noticeable trend southward on 12z ensembles. Something to watch, but it is a great example of why looking at 500 maps tells the story. IF(stress IF) that holds, somebody would likely get hammered by that. Definitely will be watching this for a few days. Huge grains of salt as climatology really doesn't support snow this early, but Fountain mentioned a great example above of this actually occurring. It is uncanny how close those maps look. I will be interested to see the trends. Also interesting, 2014-15 turned out to be a great winter. I bet the QBO dipped around then off the top of my head.

Compare that GFS ensemble sigma to the Euro operational at the same range....

@fountainguy97, that is uncanny. The 12z Euro drops 16" over the same high elevations spots as it did in 2014. Good find.

Hmmm. Well....

Looks to me like the GFS and CMC at 12z are quicker w/ the energy over the GL. The Euro slows it down and drops it into the backside of the trough. That might be an error by that model as it tends to hold energy back. I'd feel better if the GFS had it. I need to check the ensembles. But...if that were legit, that is a lot of energy to crank to our SE. The sigma maps on Weatherbell are impressive at 500 for the Euro operational.

Not many other models are showing this much development, but man....that will leave a mark. Partial phase, but doesn't get neutral in time for us. There are some nice upslope snows for those in the best spots.

We really need to start looking at a way to archive these threads and save them as an online library. It would be a huge loss to lose these. This forum is probably the best library of weather events dating back to 2014 for the Tenn Valley.

Fountain, if you go to the Oct 24th or 25th(2014 thread above) post by @tnweathernut, there is some good discussion by John, 1234, and tnweathernut. I have no idea what I was doing during that timeframe! I didn't post until a bit closer to the event which is unusual. Anyway, 1234 posted some maps of the event from about a week out. That was a fun one to track. Pretty sure there was snow in the Williams-Bryce Stadium stands in Columbia, SC, for that game.

Here are our threads: Tennessee fans had trouble getting to the game in South Carolina. This was part of a string of early season snows around that time frame. Pretty sure we were the bullseye, and it shifts SE. There are some good maps and discussion in our threads. The Capitol Weather Gang has some maps as well. Indeed, there are some photos of Erwin in our observations thread. Crazy storm.

https://www.washingtonpost.com/news/capital-weather-gang/wp/2014/11/01/incredible-early-season-snow-slams-the-southeast-impacts-felt-across-eastern-u-s/

Haha, no idea! That's hilarious. I figured it was you.