Wet and Stormy 72 Hour Forecast

Current Radar

The Potential Stormy Stuff This Evening

The Wind

Let’s talk first about the wind…and oh my the wind. We are currently under a wind advisory through midnight tonight.

Sustained winds to start the day will be around 15-20 mph. This will increase to about 20-25 mph by the afternoon. Now these are just sustained winds. We could potentially see wind gusts upwards of 40 mph through the day. This wind is expected long before any stormy weather (which would bring even faster wind speeds).

To say the least, go ahead and secure all outdoor furniture especially trampolines (God’s frisbee as David likes to call it).

Timing

Generally speaking, most models are showing the strongest storm potential moving through around the early evening hours.

HRRR has showers moving through around the 7 PM hour.

You may notice the intense red line that develops around the late afternoon, this is referred to as a “squall line”. Along this line is where we will likely see the most potential for any type of severe weather. Everything looks to move out after midnight.

Severe Weather Potential

The Storm Prediction Center currently has us in the “Marginal Risk” category (think 1 on 0-5 scale) for severe weather. The “slight risk” area is just to our West and Southwest.tn_swody1-png-1000x750-google-chrome-2016-11-28-08-41-20

Overall Wind Probability – 5% probability of damaging winds within within 25 miles. Both Davidson and Williamson Counties appear to be included.

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*Update as of 10:25, we are no longer included in the Hail Outlook*

We are currently NOT included in the Tornado Outlook. The 2% and 5% remain to our Southwest. We currently do not appear to have enough ingredients. 

As David puts it “If making a tornado was like making an omelette, tonight we have the best chef, an awesome skillet, etc., but no eggs. No egg no omelette.”

So why are we only in the Marginal Risk Category? We still lack a few key ingredients in the production of severe weather.

We have PLENTY of shear (one of our needed ingredients)

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We greatly LACK any CAPE (Convective Available Potential Energy)

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The amount of shear we have alone could bring in some severe thunderstorms with damaging wind gusts at times. Any severe weather beyond that we would need a few more of the ingredients to line up.

Conclusions

This is an event that needs to be monitored very closely. We lack CAPE right now. If we begin to see CAPE increasing, we may need to have a different conversation about the severe weather potential. Damaging winds via straight line winds are the main concern. Large hail is also a concern. A spin-up tornado can not be ruled out at this time, but does appear to be very unlikely given the current atmospheric conditions.

Continue to stick with us on Twitter @NashSevereWx throughout the day for the most up to date information.

Brief Spell of Sunshine on Tuesday

Need to get something done outside? I’d suggest you do it Tuesday morning. If you don’t do it then, you’ll likely have to wait until Thursday to get much of anything done outside. Tuesday will be nice and sunny in the morning with clouds building through the day.

Tuesday Night Into Wednesday, Another Batch of Showers (Possibly Storms Too)

More rain is on the way for us late Tuesday night.

General Timing

Compared tonight’s showers/storms, this appears to be a late evening to early morning event. The majority of us will likely already be asleep when this moves through.

NAM has the showers making their way through our area around the 3 AM mark.

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Euro likes the idea of a few showers before midnight, with the majority reaching us after midnight as well.

All in all, Tuesday evening plans look good. Likely won’t see this batch of showers and storms until after the midnight hour. Depending on the arrival, we could see some showers during the AM commute on Wednesday.

So how much severe weather will we see?

As per usual, that seems to be the million dollar question right now. Most of the models seem to show the main line of showers and storms rolling through after midnight, but before the AM commute hours, so this will likely be an overnight event on the stormy side (if we end up seeing any).

The Storm Prediction Center currently has us in the “Marginal Risk” category for tomorrow night’s storms (this is like a 1 on a 0-5 scale).

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Main threat with these storms appears to be damaging wind gusts. We could see some strong to severe thunderstorms in the mix overnight.

This system needs to be watched over the next 24 hours very closely. Initially, models were showing the surface low (mastermind of all of this essentially) that would stay fairly southward, this would cause most of the severe stuff to go to our East. Latest runs have shown the surface low going northward, which brings the severe stuff closer to home.

As of right now, this does appear to be a low-end event with damaging winds once again being the main concern.  Due to the aforementioned unresolved surface low location for tomorrow, this round of showers and thunderstorms needs to be closely monitored into tomorrow.

At the End of it All…

The combination of these two events by no means is a drought buster (we would need 6+ inches of rain to do that), however, these events will likely help out our current drought situation. Between both today’s rain and tomorrow night’s rain, the majority of us can expect to see 2 to 3 inches of rain when all is said and done.

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Rest of the Week?

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Thursday and Friday look sunny and cool with temps in the 50s. This weekend looks uncertain, but we could see another round of showers.

This website supplements @NashSevereWx on Twitter, which you can find here.