Holston_River_Rambler

Euro recent run over run trends through 12z today I stole these, hopefully KyloG doesn't kill me. That person can steal some of mine later, lol

That back edge is right over my head in Roane county ATT

Maybe some of us get some radiational cooling this PM?

Hard to see on the gif, but it has 37 at the surface around Knoxville Looks similar to NAM 3k sounding

UKMET was the furthest north its been, but the eastern valley seem to have gotten warm nosed: going to look at the soundings on pivotal

WCOSS means weather and climate operational supercomputing system

@Carvers Gap SENIOR DUTY METEOROLOGIST NWS ADMINISTRATIVE MESSAGE NWS NCEP CENTRAL OPERATIONS COLLEGE PARK MD 1620Z WED FEB 19 2020 NCO is working to recover a WCOSS dissemination issue causing current model data to be delayed. Liddick/SDM/NCO/NCEP

Nice chilly ENE to NE down valley wind here in Oak Ridge 5 - 10mph It’s got a good feel to it.

Be interesting to see exactly where the precip. shield sets up as it slide ENE

Starting to look like this one has transitioned from a pure slider to more of a Miller A/ slider combo.

You're not missing anything, as far as I can tell. That's why I said it looks more like wet snow, than what the NAM was depicting as rain.

This is the sounding that 3km NAM is showing as rain for KTYS: To me, that looks like it might more likely be big old snowflakes

WBIR's in house model showing mostly rain in the valley until 9AM Maybe not the in house model, looks a lot like the 3km NAM:

I think they're lowballing it for now, with that bolded caveat at the end. Can't remember how to look at the GEFS plumes, but SREFs for Knoxville and TRI look fairly similar. Sorry that there are no totals on the screenshots I used, but the high end plume is around 7"

@PowellVolz They had an interesting AFD this AM and expressed a lot of uncertainty for areas 40 north to bust high or low. "A lot to discuss in the extended period with chances of rain and snow, some of which could be accumulating snowfall. Models are in good agreement regarding the overall synoptic pattern but differences are apparent in the overall thermal profiles with the NAM/EURO a bit colder than the GFS/CMC in the Thursday time frame. By 12Z Thursday, the h50 pattern will feature a trough extending from the Great Lakes westward into the Rockies. Nearly zonal h50 flow will traverse the Tennessee valley. At the surface an area of surface low pressure will develop across the Gulf coast with a frontal zone extending northeast and a strong high moving out of the northern plains. The eventual strength of this high will likely have a great influence on how far north the precip can move north and how quickly the cold air will arrive. Favorable upper level dynamics will overspread much of the southeast including the Tennessee valley 12Z onward which along with overrunning will lead to an expansive zone of precipitation from the TN/GA state line southward. It is expected that this precipitation will gradually make its way north through the day Thursday in response to a strengthening 850-700mb frontal zone as the surface low lifts northeast. However as mentioned above the strength of the surface high will play a role in the overall northward progression of the precipitation field. Forecast soundings, and 2-D planviews indicate the thermal profile will be sufficient for much of the precipitation to start as snow before warmer air moves north changing the snow to rain. Much uncertainty still resides in how cold the lower troposphere becomes during the day Thursday. The ECMWF and NAM12 show rather strong CAA as the surface high slides south into the Tennessee valley. This may actually offset the normal increasing diurnal temperature trend. This results in much lower confidence in snow accumulations in the southern and central valley, but believe if any accumulations would indeed occur they would be on grass and elevated surfaces. As far as model guidance is concerned the NAM/EURO are in agreement regarding overall max temperatures in the 925-700MB layer while the GFS and CMC mirror each other more. Decided to favor a model blend of the ECMWF/GFS along with the GEFS means. Ensemble plumes still show a great deal of spread regarding snow amounts but am seeing some clustering around a dusting to a half inch for locations such as CHA, and TYS. Even more spread is being observed across SW Virginia and extreme NE TN where no noticeable clustering can be seen indicating higher uncertainty across these areas. Nonetheless confidence is high enough that most locations will likely see snow fall especially from 12Z - 18Z Thursday as Omega and RH are most favorable in the DGZ during this time period. However, warming near surface temperatures and an increasing February sun angle will be working against heavier snow accumulations especially for the southern and central valley. Areas further north across SW Virginia, the Cumberland Plateau will likely see the snow last longer and could receive upwards of a dusting to a half inch of snow. The higher terrain of the Tennessee mountains will see the heaviest accumulations where 1-3 inches of snow could fall. Confidence in forecast snow amounts are still fairly low, and because of this, decided against issuing any winter weather advisories at this time. Additional changes to the forecast are most certainly going to occur and later shifts may need to issue an advisory across portions of the area."

Regardless of what happens, not a bad set up at the surface this AM: High nosing down and a surface front from New Orleans to the Outer Banks.

Not sure, but watching it over the past few days it has had one of the strongest HP depictions.

Yeah, kind of/ sort of worried given that. It was overzealous with the early December bit and here is only very gradually ticking north.

And I mean that wind howl up here in Morgan County. Front's through, wind's blowing, and the temp is falling.

I rolled the dice and started a thread.

To the tune of All along the Watchtower (Hendrix version) There must be some kind of way out of winter said the Rambler to met Jeff there's too much confusion can't get no relief The southeast ridge, it flexes north troughs dump in the west the Euro won't level with my mind will the NAM prove its worth? No reason to get excited nrgjeff he kindly spoke there are many in the valley, who think that snow is but a joke but you and I, we've been through that and this is not our fate so let us not trust the Euro the hour's getting late... All along the river valleys snowhounds kept their view while model runs came and went SREF plumes too outside and up to the north a big HP dropped down two shortwaves were approaching and the wind began to howl....

Good news is we will at least start to see reality on radar this time tomorrow.

3km NAM, while not a throat punch to the northern plateau, is at least a wicked jab.

18z Euro. Finally figured out how to make these on my phone: https://giphy.com/gifs/VeZ269fobmDUjSeJQL

Here's the radar loop from the storm(s) I think y'all are talking about.