Holston_River_Rambler

6z Euro:

This may not be a huge deal, but height fields are a little less suppressed on the 6z Euro over the TN Valley and at hr 84: 6z on left, 0z on right:

Just have to keep it together: EDIT (running joke about thunder in the mountains = snow; below is the GOES derived lightning product)

IMO they seemed more optimistic for early next week than usual. Not sure if that is a good or a bad thing for my very weird snow superstitions at his range: Clouds increase on Sunday night into Monday, and light precipitation is forecast to overspread the region during the day on Monday. This will be in response to divergence associated with a strengthening 300mb 140 kt upper jet across the Central Appalachians through the Mid-Atlantic. Low-level convergent 850mb flow will increase and overrun the cold air at the surface. GFS forecast soundings for Monday show a saturated profile through the DGZ with temperatures below freezing through the entire atmosphere. Surface temperatures would likely be in the mid 20s while precipitation is falling which would result in higher SLRs. Deterministic models and ensembles are in good agreement with the setup for Monday. The big question is the exact amounts of QPF. The ECMWF is showing closer to 0.1 inch, the GFS is near 0.3 inch, and the GDPS is around 0.3 inch. With colder temperatures resulting in higher SLR of 12:1 to 16:1 according to the NBM on Monday afternoon through Tuesday morning, any small changes in liquid QPF will create large changes to expected snow totals. At this time, we will continue with around 0.2 inch QPF for this system which is producing a mean of 2 to 3 inches of snow. The NBM probabilities for 1 inch of snow in CHA is around 40 percent, at both TYS and TRI the probability is around 70 percent. As we head into Tuesday, bigger questions arise. The GFS and GDPS are more progressive and negatively tilted with the approaching shortwave and upper trough while the ECMWF is less progressive with this shortwave and results in a weaker surface low. While the deterministic ECMWF shows the weaker solution, many of its ensembles continue to show a stronger system with higher QPF and potential snow on Tuesday. For this reason, there is still a lot of uncertainty on Tuesday about any potential wrap around moisture with this southern low pressure system. With the stronger solution, we likely get another 0.1 to 0.3 QPF, and with the weaker solution, we get near nothing. The GFS ensembles are consistent with the stronger solution which would keep precip, and snow, around through Tuesday night, and perhaps Wednesday morning. These details won`t be resolved for several days.

You and I are on a similar wave length. I was just reading the AFD too, lol.

An ancient weenie rule, so prepare your bodies. The NAVGEM used to be considered to have the most progressive bias, so if it was more amped than some of the more reliable global OPs, it was a good bet that they would adjust to a more amped solution:

Even the ever stingy NBM is looking acceptable this morning:

It's a unique set up IMO

18z : 12z:

The 18z control was definitely a bad run for Nashville, but better for east TN folks. I would say it was on its own at 12z but if we count the Euro ensemble control as a low resolution version of the operational, that run was much better for eastern areas than 12z.

If we count the control as having any bearing on the Euro OP that run was a small scootchle towards the GFS

18z Euro control is definitely producing more precip over east TN than the 12z control. little less press from the TPV in Canada.

I think for everybody east of Nashville its sketchy.

My silliness aside, like some of you have said, there is still upside to even that run (it could trend better) and downside or it could trend much worse (viz. Euro)

I think that's a Title IX violation.

Here is the run:

I'll post a gif of the system and snow totals for posterity when its over

Out to 105 and three areas of LP are trying to form in the Gulf, S GA, and the Atlantic

Def looked good for western areas.

I think there may still be some shifts until the cutter works its way through by Saturday.

18z GFS is rolling. Time to spin the wheel of fortune.

Don't forget posting some long range hi-res precip output to get hopes up:

At least we still have the storm tomorrow to run into and change up that big low.

There’s a lot riding on how much thunder we get tomorrow.

At least we still have one of the Euro machine learning models: