Strong/Severe storms Possible Tuesday Night

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SUMMARY

We are certainly off to a foggy start this morning! A weak frontal boundary has drifted into Tennessee and it is bringing some very foggy conditions with it. The boundary will begin moving northward in the next few hours, as it transitions into a warm front. Once we’re south of the warm front, we’ll find ourselves in a very warm, humid airmass. This airmass will stay in place for Tuesday and will still be here when our next big cold front moves into the state. This will set the stage for possible strong to severe t-storms Tuesday night. Ahead of the front, winds will be quite gusty on Tuesday, at times possibly gusting to 40+ mph out of the south. This could bring down some shallow-rooted trees, especially with our saturated grounds. The greatest risk for severe storms will be in an area west of Nashville and north of I-40. However, some of these storms may still be packing a punch when they reach the plateau, with damaging straight-line winds being the primary threat.

Once the front passes, temps will drop considerably. By Wednesday morning we may only be in the mid 30s, and we’ll struggle to climb into the 40s during the day. With lots of sunshine of Thursday, we’ll warm up considerably, just in time for our next system that begins arriving Thursday night.

Below is the outlook for severe weather for Tuesday/Tuesday night issued by the Storm Prediction Center. Notice that the greatest threat is west of Nashville, though we are still in the slight risk along the plateau.

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I took this pic at the top of my driveway this morning. It was very foggy this morning!

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DISCUSSION

I’ll be watching the storms all day tomorrow, and posting updates on Facebook and here, as needed.  At this time, the tornado threat doesn’t look too impressive, but we can’t let our guard down. The wind fields are such that brief spin-ups are possible, especially to our west. Our greatest threat here on the plateau should be straight-line winds.

In order to get high tornado potential, there needs to be a lot of turning of the winds with height. For instance, if you have southeasterly winds here at the surface that quickly turn to the southwest as you go up into the atmosphere, you would have winds highly favorable for rotating t-storms with possible tornadoes. That’s a 90-degree turn with height. The quicker the winds make that turn as you go up, the greater the tornado potential. Tuesday evening’s winds are looking like they will be southwesterly here at the surface, turning to the west as you go up into the atmosphere. That is enough of a turn to get some brief spin-ups, but not enough to get widespread, damaging tornadoes. There is one model that suggests that our surface winds will be more out of the south, turning to westerly as you go up. That would, of course, mean a bit more of a turn to the winds, which would increase our tornado threat a bit. I’ll keep an eye on those wind fields tomorrow and let you now where we stand with that as we go through the day.

This does not look like a tornado outbreak for the plateau.

For those of you who completed the storm spotter classes, your activation may be needed tomorrow evening.  Those spotter reports are absolutely critical in getting out the most accurate warning information. I expect severe weather watches to be issued by sunset Tuesday that will run through the evening.

It looks like the severe weather threat will hold off until about 8:00 p.m. and will have ended by 2:00 a.m., but I’ll update timing tomorrow. The later the storms move in the weaker they will be. Earlier storms would be able to draw strength from daytime heating, whereas later storms would be moving into a cooler, more stable airmass.

The unsettled weather pattern continues right on into next week. On average, temps look to stay slightly below normal and precip should be above normal.

Be aware that Thursday morning temps could be in the mid 20s, just in case you have plants you need to protect from freezing temps.

I’ll keep an eye on your Tuesday night storms, as you all know I will!

This is a pic I took Easter morning out in our garden. The peach tree blossoms are getting very pretty! It’s definitely spring time on the plateau.

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