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Warming Up. Looking Ahead to Mid/Late Week Storms

Current Official Hourly Observation (taken at :53 on the hour)

Current Radar Loop

Temp & Rain Probabilities Next 36 Hours (auto-updating)

Saturday – Too Cold 10 PM 43

Winds will begin the taper off after sunset.

We’ll have to wait until tomorrow to see any meaningful sun.

Sunday – Cooler, Sunny – Morning Low 35 / Afternoon High 62

That’s better.

Monday – More Sunshine – Morning Low 40 / Afternoon High 72

Very, very nice.

Official Extended NWS Forecast:

Severe Weather Outlook

The concern for severe weather Thursday/Friday remains.

In Tuesday’s post we talked about how important the track of a low “L”pressure center can be. That’s one of several ingredients necessary for severe weather. It looks like the ingredients just MIGHT come together next week. The “L” may track through AR, MO, IL, which would be particularly concerning for Middle Tennessee.

What I’m about to go over are only two big ingredients needed for strong/severe storms. There is are more, but I don’t want to nerd this up too much.

All thunderstorms need “fuel.” That fuel is moisture, which is measured by the dew point (humidity). Dew points in the 60s (yellow and orange colors on the map) are enough fuel for big, bad storms.

GFS dew point model Thursday 1 am – Saturday 7 am:

Canadian dew point model Thursday 7 am – Saturday 1 pm:

The European model (not pictured) brings in more moisture further north. Not all three of models “agree” on the exact timing of the arrival of the 60s dew points, but they generally agree we’ll see dew points in the 60s late next week.

Ignition. That’s the low pressure system. Attached to the “L” is a dry-air-toting cold front, which will collide into the warm, wet air already in place. This will create instability, and set off the storms.

Remember, the closer the “L” moves to us (with it on the north side, us on the south side), the higher the severe potential.

Watch the tiny red “L” move on the maps below:

GFS model Thursday 1 am – Saturday 7 am:

The track for this low has been further south than some of the previous model runs, which would be more conducive for severe weather. It’s not the strongest low pressure in the world, but it’s certainly enough to cause problems. If the low actually ends up tracking a little further south, I’ll be more concerned about this possible severe weather setup.

Canadian model Thursday 7 AM – Saturday 1 PM:

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This model has the track of the low a little further north than GFS, but overall, the tracks are similar.

European model (not pictured) wants to push the worst of the weather in Friday morning, which would be the best news for us because the atmosphere would be most stable. The track of the low is almost a hybrid of the Canadian and GFS model.

The SPC (Storm Prediction Center) does not have anyone outlooked this far out because the models are not agreeing with each other enough for them to confidently outline an area:

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However, SPC expects they will reissue an outlook area if/when the models become more consistent.

This website supplements info @NashSevereWx on Twitter.

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