Tornado Watch (TN)

 So the squall line has started to enter Western and Northern Tennessee now. 

8:39 PM - And now is a great example of how forecast soundings help us out in real time. This was taken from a balloon launch at 7 PM CDT (00 UTC). It looks like the warm, unstable air is enough to overcome the capping inversion that was in place earlier in the day, as the squall line approaches now. Temperature of 70, dewpoint of 64. Moderate to strong instability with CAPE values at the surface at 1,585 j/kg. Lifted Index between -3 and -5. Bulk shear between 40-60 knots. Helicity over 200 units at both 3 km and 1 km. Lapse rates in 5-7 range. Supercell composite of 7, significant tornado parameter about 1-2. So the Nashville area is ripe for large hail, damaging winds, or even a tornado developing as these storms move in over the next few hours. It's a good example in real time. 

Birmingham already has CAPE at the surface above 1,000 joules and Lifted Index of -5. So that's certainly ample instability to work with. And that capping inversion looks like it is struggling to hang on. We don't have the wind shear in place yet, but things on the Alabama side should be ripe for severe weather too by Midnight or so. 

9:39 PM - We do have a low risk of flash flooding from some of the storms tonight in this squall line. 

But the main threat is damaging winds. You can see severe thunderstorm warnings all up and down this squall line in Tennessee up into Kentucky. The tornado warning for the storm moving into Clarksville was cancelled early because the storm was no longer showing the rotation on radar. There were a lot of damaging wind and hail reports earlier today in the Midwest into the Ohio Valley. 

9:44 - Tornado reports have been sparse so far, but one was seen by the public in Naylor, Missouri. Or actually it looks like that's the information for the one near Croton, Michigan. Looks like no info yet for the one reported in Missouri. This has still been quite an event already just in terms of wind damage and large hail reports. 

9:57 - There are a few storms within this squall line showing rotation at times though. We've got a Tornado Warning for a storm coming out of Waverly, TN and also one that is headed up toward Bowling Green, Kentucky. 

10:13 PM - And now there is a third such storm headed for Lexington, TN. Folks down around Waynesboro or Hohenwald, definitely watch these storms closely. Because I remember yesterday it was really looking like a potential hot spot. And then NWS Nashville even mentioned that in their discussion tonight. 

10:16 - Okay and this tornado East of Waverly was confirmed by a debris signature earlier. Doesn't look like much at the moment, but showing the velocity signature since it does look fairly impressive. 

And actually right before I could take that screenshot, a new scan came in, so you see the very weak rotation above. Sometimes it's that way with squall lines. 

10:19 - But people in that path, from Tennessee City all the way up to Vanleer, should go to their tornado shelter. If you're in a sturdy site-built house, that's a small interior room on the lowest floor, away from windows. 

10:21 - And now a new tornado warning for Dickson, Humphrey's, and Hickman counties to the South of that other one. 

10:23 - One of the small communities in this latest polygon is actually called Bucksnort.

10:27 - And this squall line will likely enter Northwest Alabama between Midnight and 1 AM. 

10:39 - Ok from Humphreys County, emergency management reports the roof taken off a house by this tornado earlier. 

And that came from the centermost of these three Tornado Warnings in Middle Tennessee. 

10:43 - And the severe thunderstorm warnings issued ahead of this squall line now include the city of Nashville as well as some points to the South. 

10:45 - And it's going to continue to be a fun night, the Storm Prediction Center advises, especially for West Central and Southwest parts of Tennessee. 

10:49 - By the way, for this Severe Thunderstorm Warning that includes Nashville and Goodlettsville, 70 mph wind gusts are possible. That's almost getting up to hurricane force. 

10:50 - Just got a new Tornado Warning for Perry County. 

And that's for that storm coming out of Lexington, NWS Nashville giving plenty of advance warning for this storm. 

10:52 - And that's moving into that zone that looks the most favorable for tornadoes tonight, in Southwestern Middle Tennessee I guess you'd call it, getting close to Linden and Waynesboro. 

10:56 - And we've got a new Tornado Warning now that includes the town of Fairview and the city of Franklin there in Williamson County. This is from the storm that produced damage earlier, tornado damage, in Humphreys County. So I'd definitely respect this warning. Get to that lowest, most central part of your house and cover your body, especially your head, if in this polygon. 

11:01 PM - We're down to two tornado warnings now, the one coming up on Linden in Perry County and the one moving toward Franklin in Williamson County. Anywhere in these polygons you need to be sheltered to be on the safe side. It's night, and tornadoes can change course quickly. The one coming up on Franklin had confirmed damage earlier, took a roof off a house. And at times it's tried to show that classic comma-head look you often see on reflectivity with a tornado. 

11:04 - the Nashville Severe Weather YT channel is streaming for this. 

11:05 - And here's a look at how that couplet is hanging together, showing fairly tight rotation in this storm still at times. 

11:06 - And here's our Tornado Watch down on the Alabama side. 

Will start a new post to detail that. 

SEL8

   URGENT - IMMEDIATE BROADCAST REQUESTED

   Tornado Watch Number 78

   NWS Storm Prediction Center Norman OK

   825 PM CDT Sun Mar 30 2025

   The NWS Storm Prediction Center has issued a

   * Tornado Watch for portions of 

     Central Kentucky

     Western and Middle Tennessee

   * Effective this Sunday night and Monday morning from 825 PM

     until 300 AM CDT.

   * Primary threats include...

     A few tornadoes likely with a couple intense tornadoes possible

     Scattered damaging wind gusts to 70 mph likely

     Scattered large hail and isolated very large hail events to 2

       inches in diameter possible

   SUMMARY...Strong to severe thunderstorms are ongoing within a

   convective line that extends from southern IN through western KY

   into western TN. This line is expected to continue eastward into the

   moist and moderately unstable airmass downstream across central KY

   and western/middle TN. The environment supports a continuation of

   the ongoing strong to severe storms. Persistent moderate to strong

   low-level shear will support the potential for tornadoes embedded

   within this line. Large hail and strong gusts are possible as well.

   The tornado watch area is approximately along and 60 statute miles

   east and west of a line from 45 miles northeast of Bowling Green KY

   to 105 miles southwest of Nashville TN. For a complete depiction of

   the watch see the associated watch outline update (WOUS64 KWNS

   WOU8).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Tornado Watch means conditions are favorable for

   tornadoes and severe thunderstorms in and close to the watch

   area. Persons in these areas should be on the lookout for

   threatening weather conditions and listen for later statements

   and possible warnings.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 72...WW 74...WW 75...WW

   76...WW 77...

   AVIATION...Tornadoes and a few severe thunderstorms with hail

   surface and aloft to 2 inches. Extreme turbulence and surface wind

   gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean

   storm motion vector 27040.

   ...Mosier

WOUS64 KWNS 310129

   WOU8

   BULLETIN - IMMEDIATE BROADCAST REQUESTED

   TORNADO WATCH OUTLINE UPDATE FOR WT 78

   NWS STORM PREDICTION CENTER NORMAN OK

   825 PM CDT SUN MAR 30 2025

   TORNADO WATCH 78 IS IN EFFECT UNTIL 300 AM CDT FOR THE

    FOLLOWING LOCATIONS

   KYC001-003-009-031-045-053-057-061-087-099-123-137-141-155-169-

   171-207-213-217-227-310800-

   /O.NEW.KWNS.TO.A.0078.250331T0125Z-250331T0800Z/

   KY 

   .    KENTUCKY COUNTIES INCLUDED ARE

   ADAIR                ALLEN               BARREN              

   BUTLER               CASEY               CLINTON             

   CUMBERLAND           EDMONSON            GREEN               

   HART                 LARUE               LINCOLN             

   LOGAN                MARION              METCALFE            

   MONROE               RUSSELL             SIMPSON             

   TAYLOR               WARREN              

   TNC005-017-021-023-027-037-039-043-055-069-071-077-079-081-083-

   085-087-099-101-109-111-113-117-119-125-135-147-149-159-161-165-

   169-181-187-189-310800-

   /O.NEW.KWNS.TO.A.0078.250331T0125Z-250331T0800Z/

   TN 

   .    TENNESSEE COUNTIES INCLUDED ARE

   BENTON               CARROLL             CHEATHAM            

   CHESTER              CLAY                DAVIDSON            

   DECATUR              DICKSON             GILES               

   HARDEMAN             HARDIN              HENDERSON           

   HENRY                HICKMAN             HOUSTON             

   HUMPHREYS            JACKSON             LAWRENCE            

   LEWIS                MACON               MADISON             

   MARSHALL             MAURY               MCNAIRY             

   MONTGOMERY           PERRY               ROBERTSON           

   RUTHERFORD           SMITH               STEWART             

   SUMNER               TROUSDALE           WAYNE               

   WILLIAMSON           WILSON              

   ATTN...WFO...LMK...OHX...MEG...

WATCH COUNTY NOTIFICATION FOR WATCHES 72/78

NATIONAL WEATHER SERVICE MEMPHIS TN

832 PM CDT SUN MAR 30 2025

ARC035-037-093-111-123-MOC155-TNC033-045-047-053-075-095-097-131-

157-167-183-310400-

/O.CON.KMEG.TO.A.0072.000000T0000Z-250331T0400Z/

TORNADO WATCH 72 REMAINS VALID UNTIL 11 PM CDT THIS EVENING FOR

THE FOLLOWING AREAS

IN ARKANSAS THIS WATCH INCLUDES 5 COUNTIES

IN EAST ARKANSAS

CRITTENDEN            CROSS                 MISSISSIPPI

POINSETT              ST. FRANCIS

IN MISSOURI THIS WATCH INCLUDES 1 COUNTY

IN SOUTHEAST MISSOURI

PEMISCOT

IN TENNESSEE THIS WATCH INCLUDES 11 COUNTIES

IN WEST TENNESSEE

CROCKETT              DYER                  FAYETTE

GIBSON                HAYWOOD               LAKE

LAUDERDALE            OBION                 SHELBY

TIPTON                WEAKLEY

THIS INCLUDES THE CITIES OF ALAMO, BARTLETT, BLYTHEVILLE,

BROWNSVILLE, CARUTHERSVILLE, COLLIERVILLE, COVINGTON, DRESDEN,

DYERSBURG, FORREST CITY, GERMANTOWN, HARRISBURG, HUMBOLDT,

MARTIN, MEMPHIS, MILAN, MILLINGTON, OAKLAND, RIPLEY TN,

SOMERVILLE, TIPTONVILLE, UNION CITY, WEST MEMPHIS, AND WYNNE.

$$

TORNADO WATCH OUTLINE UPDATE FOR WT 78

NWS STORM PREDICTION CENTER NORMAN OK

825 PM CDT SUN MAR 30 2025

TORNADO WATCH 78 IS IN EFFECT UNTIL 300 AM CDT FOR THE

 FOLLOWING LOCATIONS

TNC005-017-021-023-027-037-039-043-055-069-071-077-079-081-083-

085-087-099-101-109-111-113-117-119-125-135-147-149-159-161-165-

169-181-187-189-310800-

/O.NEW.KWNS.TO.A.0078.250331T0125Z-250331T0800Z/

TN

.    TENNESSEE COUNTIES INCLUDED ARE

BENTON               CARROLL             CHEATHAM

CHESTER              CLAY                DAVIDSON

DECATUR              DICKSON             GILES

HARDEMAN             HARDIN              HENDERSON

HENRY                HICKMAN             HOUSTON

HUMPHREYS            JACKSON             LAWRENCE

LEWIS                MACON               MADISON

MARSHALL             MAURY               MCNAIRY

MONTGOMERY           PERRY               ROBERTSON

RUTHERFORD           SMITH               STEWART

SUMNER               TROUSDALE           WAYNE

WILLIAMSON           WILSON

$$

ATTN...WFO...LMK...OHX...MEG...