Winter in November

To the men, women, and families of those who serve: Thank you.

Tonight – A Little Rain, Then The Big Cold Front Arrives – Temps Falling Into the 30°s Overnight

At noon, the big cold front was about to cross the MS River into Tennessee:

Expect light rain off and on through midnight. The HRRR expects the bulk of the rain around 7 PM:

Which is right around the time we expect temperatures to start to tumble toward the 30°s:

Wednesday — Much Colder — Wake Up 37° (Wind Chill 31°), High 47°

The rain will depart, but an intense high pressure system to our west will transport very cold air into Middle Tennessee on Wednesday, Thursday, and Friday.

Temps will hover near freezing around kickoff Friday night, then dip below freezing for the second half.

What About S–w?

Before digging into this, our standard disclaimer:

It’s that time of year where if you look far enough out on some of the global weather models (GFS, Euro), you can find snow. Those models aren’t always wrong, but they are far from a reliable indicator of snow, which is one of the most difficult things to forecast in Middle Tennessee. It’s hard to get a good snow forecast inside 12 hours of the expected event. Trying to nail it down 72, 144, or 200+ hours away is, as @spann says, voo-doo science.

But, the models aren’t totally worthless that far away, so just remember to use them for entertainment value only and rough/general guidance. These models can be pretty good for picking up broad patterns and trends, but are awful at pinpointing the existence/timing/intensity of a snow event 3+ days into the future. 

Saturday Night. We expect to see an increasing clouds on Saturday, with highs only in the low to mid 40°s. A weak surface front combined with upper level disturbances are expected to scoot through Saturday night. As light precip falls on Saturday night, it will drag down the temperature (evaporating water cools the air), and maybe deliver some freezing temps at the surface. We could see a brief period of mixed precip, but that’s more likely the closer you live to the KY border. The period of mixed precip would be short-lived, and certainly wouldn’t survive past sunrise Sunday, when temps are expected to begin to rebound into the 40°s.

The GFS model paints a rather snow-optimistic portrait for Sunday at 5 AM. It’s a little hard to believe. You’d be wise to view this with a lot of skepticism.

Sunday Night. More arctic air is expected with yet another rain/snow mix possible overnight Sunday and into Monday morning. Just like the day before, temps will begin to warm above freezing after sunrise Monday, before settling in at a high temp in the low/mid 40°s.

The GFS model doesn’t think we’ll see much, if anything, snow-wise. Here is 1 AM Monday:

The 12z11Nov14 run of the Euro model thinks snow will miss us both Sunday and Monday. You’ll have to go to KY to see it.

This website supplements @NashSevereWx on Twitter.