NWS Nashville – “Special Weather Statement”
A powerful storm system will move across the Tennessee Valley this weekend, bringing much warmer temperatures to Middle Tennessee today and especially by Saturday. Showers and a few thunderstorms are also anticipated Saturday afternoon and into the evening. Some storms may be strong to possibly severe. Saturday night, an arctic cold front will sweep across Middle Tennessee, bringing much colder air back into the area. As this occurs, rain may changeover to a wintry mix of freezing rain or sleet late Saturday night into Sunday morning before precipitation ends. However, only light ice accumulation amounts look possible at this time.
Act 1 – Temperature Climb and T-Storms
Increasing pressure fields will lead to gusty winds (20-25 mph) beginning overnight and continuing into Saturday. Also, some showers are anticipated after midnight, modeled by the latest high resolution model:
The low temperature of 45° will come shortly after midnight as temperatures rise into the morning hours ahead of the main cold front. We are forecasting 70° for Saturday PM.
Let’s talk about Saturday afternoon…
Showers and a few rumbles of thunder will be with us through a good portion of the day on Saturday. Stronger storms are expected to develop to our west associated with an increase in rising motion characteristics ( this helps storms grow). The storms, as they progress to the east, could pose a damaging wind threat to middle Tennessee. Higher resolution models, like the NAM, pick up on this feature quite nicely.
NAM 9PM Saturday
In lieu of this, the Storm Prediction Center has placed Davidson and Williamson counties under a marginal risk for severe weather:
We will be keeping a close eye on any storms that are looking to misbehave on Saturday night.
Act 2 – Potential Wintry Mix
Following the bumpy storms Sat. evening, temps will drop quite substantially.
…from 64° at 9PM Saturday to 29° by 6AM Sunday. That’s impressive.
Now, depending on how much moisture is left over Sunday morning, our area could experience a little changeover to a wintry mix (freezing rain, then sleet/snow). It is very uncertain as to how much precipitation will fall behind the cold front. However, it appears that accumulations will be small to none and any wintry mix that does develop will quickly move east of our area by midday Sunday. Here’s how the GFS plays it out:
If anything, this will give us an inkling as to what may come later this winter.
Act 3 – A Break In the Action
Some quiet time will restore normalcy with temps a few degrees below average to start the week. We’ll warm back into the 40s before another storm system looks to eject out of the West by Thursday and into next weekend.
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