2:42 PM – The National Weather Service issued a Special Weather Statement for both Davidson and Williamson Counties for Monday into Tuesday morning.
2:30 PM – The Storm Prediction Center put out a Mesoscale Discussion that included Middle Tennessee. It has confirmed, however, that the system has missed us to the east.
Summary —- At least one strong storm cluster expected Sunday afternoon with tiny tornado chance – Windy Monday – Squall line producing torrential rain, damaging winds, and maybe an isolated tornado late Monday night
Current Radar Loops:
Sunday – Afternoon Strong, Possibly Severe, Storms – High 76
We aren’t expecting measurable rainfall for several hours. Instead, how would you like some patchy fog and drizzle?
A warm front is lifting back over Middle Tennessee. By this afternoon and evening, “some strong to severe storms are likely…with wind damage being the main concern. Localized heavy downpours could cause some brief standing water.” (NWS Morning Forecast Discussion).
The Storm Prediction Center has included us in its 2% probability that these storms may produce a tornado within 25 miles of us:
That EF-1 tornado in Hickman County Friday night came inside a 2% tornado risk — the first one I can remember coming out of a 2% tornado risk in a long time. So, just know the tornado threat is “not zero.”
The HRRR thinks those storms will start rolling in around 4 PM. Don’t fixate on that timing; it could be earlier or later than then.
Monday – Damaging Winds, Flash Flooding, Tornado(es) All Possible Late Monday Night – High 81
Overview. Here’s a cut-and-paste from the NWS morning forecast discussion: THE MAIN FOCUS THIS FORECAST PERIOD CONTINUES TO BE ON MONDAY EVENING…WHEN A BAND OF THUNDERSTORMS IS EXPECTED TO MOVE INTO MID TN WITH WIND DAMAGE AND FLASH FLOODING. THIS EVENT WILL ALSO BRING THE POTENTIAL FOR ISOLATED TORNADOES.
(The ALL CAPS is not them yelling at us. It’s just how their forecast discussion is written)
When. We’ll start the day windy, with winds sustained at 20-25 MPH, gusting to 30 MPH. A Wind Advisory may be issued to account for that.
Meanwhile, a squall line will be forming to our west, thanks to some impressive severe-weather-making ingredients you don’t want me to nerd out about here. The entire system will start marching east in our direction through the day.
Weather models don’t agree on the exact arrival of this line in Davidson & Williamson Counties. Our NWS thinks the squall line will reach the Tennessee River by Monday evening. This may arrive here late Monday night or — GULP — the wee hours of Tuesday morning.
What. The main threat will be damaging straight line winds inside — and just ahead of — the storms.
“Due to the impressive winds and shear profiles…bowing segments along the line could contain isolated tornadoes.” (NWS Morning Forecast Discussion).
Torrential rainfall is expected Monday night, totaling 1.5″ to 3″, with locally heavier amounts. A Flash Flood Watch will likely be issued before Monday evening.
Please don’t ignore the flash flooding potential. We got a lot of rain this past week. We’ll get more today. The biggest danger this storm presents is the water it’ll produce. If you don’t have to drive when this storm arrives, don’t. The winds will be crazy high, with visibility almost nil.
Confidence. “Although the line is expected to lose some punch as it crosses Middle Tennessee Monday night…This system looks powerful…and could produce severe weather across all of our area…including the Plateau.” (NWS Morning Forecast Discussion). Translation: there’s no such thing as certainty in a 36+ hour forecast, but this storm is expected to weaken and still produce 58+ mph wind gusts and isolated tornadoes.
The Storm Prediction Center’s Outlook for Monday has us within a 15% probability for a severe weather event. Additionally, the SPC has moved us out of the Hatched area that denotes a 10% or greater probability of a “significant severe weather event” happening no further than 25 miles away from us:
It appears the SPC is beginning to think the line of thunderstorms will begin to loose some of it’s intensity just before reaching Nashville.
Remember — no warnings are ever posted to this website. Consult multiple sources for severe weather information. This website supplements @NashSevereWx on Twitter.
Categories: Forecast Blogs