John1122

The very worst part of any rain to snow system is the wait. We had one last year and it seemed to take forever.

Rain finally picked up here. Just drove home and it has that splattery look to it. It's 43 degrees though, so I expect the 11pm or later changeover.

Just got home from Hixon. It was 57 when I left there but you could feel the cooler air moving in then. It's 46 here at home. Hopefully I'm not stuck in the middle, too far east for the transferring low and too far west for the trowel.

I couldn't be more baffled by the NWS disco from MRX and BNA. They mention several inches of snow possibly melting by day break with a low in the low to mid 20s? The ground is warm but if that happens it will be something I have never seen, even in April snow events. I don't know what they are looking at to bump totals in some areas but suppress totals in others. Especially around Crossville/Central Plateau which is showing up with 4-7 inches across basically all guidance.

Latest RAP. You can see the lighter areas south of Frozenhead/Cross Mtn and South of High Knob that Daniel Boone mentioned. Even they are filling in as we go forward. Looks like the sleet area is about 1 County wide in western areas with heavy snow right behind that.

The 17z HRRR is also coming in a bit less snow holey but it still has some of them. Overall it's a pretty good run for us. I actually think they could be under modeling the NW quadrant for such a track so close to the mountains.

Final Euro call.

17z RAP further closed snow holes except right over Chattanooga. Looks more uniform across the state.

16z RAP closing the snow hole a bit. It's still snowing in the East at this time.

I'd guess it's more what Holston says. Down sloping off Cross Mountain and Frozenhead when a LP takes a certain angle.

I've seen the snow hole you're referring to play out several times before. I'm not 100 percent sure what causes it. It really tends to hit Anderson County.

06z GFS and 09z RAP are just huge. The RAP gets us all.

Very rare sight, the entire forum area is under winter weather products this morning except for far NE Arkansas. Looks like every county in Tennessee is under a WWA or WSW. In addition to the not from above, MRX disco did mention they may need to expand the WSW to the west.

Lots of warnings and advisories issued by MRX. They are basically saying this is an East based event. Winter Storm Warning for areas East of Knox. Have my area with less snow than Knox and central Valley areas. Possible for sure but it definitely doesn't line up with most modeling for the Plateau vs the valley.

The final 06z NAM map may quite literally get everyone who posts here. Memphis, NE Arkansas, SWVa, North Miss, North Alabama, Chattanooga, SE Kentucky, we all got snow with it.

Under 24 hours and the NAM is also holding steady. The exact areas of heaviest snow will move around some but it looks like we are all in line for fast and furious thumping. I expect the issuance of winter products with the morning package

I will be stunned if they aren't but man I sure hope they are right or even 50 percent right.

This will be an unusual event as far as days leading into the potential snow. About as close as I can remember right off the bat was March into April 1987. Temps were 68-77 for highs from around March 20th to March 31st. It did get cold a couple days before the snow hit. However the day of the snow was 50 for the high. Temps crashed that afternoon and heavy rain changed to heavy snow and 8-12 inches fell in the area. I don't know if we will see those dynamics with this system but that was huge silver dollar sized flakes that just ripped down for several hours. It coated the ground quickly. We had about 2 or 3 inches in a late April event that was similar as far as heavy rates quickly overcoming ground temps. Rates basically trump all. Especially with a lower sun angle or at night.

Its rare to see NW Tennessee and NE Tennessee included in a snow cover map. It's slightly more common to see Memphis and Bristol with snow from a clown.

I've found it best to take those clown maps and shave off 40-60 percent for wet snows that aren't falling onto frozen ground. Sometimes you'll get over performance and they'll match up. You can snow board, clean it off and add the measurements up and you'll get closer to the clowns.

Depth is estimated taking into account compacting, ground temps, etc.

If we get low amp 8-1 into the heart of winter (Jan 15th-Feb 20th) I like our odds for more cold in the future.

GFS has ensemble support. Big uptick.

If the RAP was legit we'd have one of the best Memphis to Bristol events in many years.

It sounds counterintuitive but having wet ground when it's warmer actually aids in snow fall but if it approaches the rates modeled it will pile up and fast.