Alert archive / Tennessee / Severe Thunderstorm Warnings in 2010

Severe Thunderstorm Warning 14, NWS Nashville, TN

January 21, 2010Robertson County, Sumner County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Jan 21, 2010, 5:54 PM CST for Robertson County, Sumner County, Tennessee. It was in force for 21 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jan 21, 2010, 5:54 PM CST (23:54 UTC)
Expired: Jan 21, 2010, 6:15 PM CST
In force: 21 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon

Counties Robertson County, TN, Sumner County, TN

The radar

The Nashville radar (KOHX), 29 km from the middle of the area, began a volume at 23:53 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jan 21, 3:16 PM CST	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 11.9 hours before the alert went out and 41 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 24 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 540 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 108 m²/s²
0-3 km storm-relative helicity: 73 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Nashville, TN wrote its last area forecast discussion before this severe thunderstorm warning went out at Jan 21, 3:06 PM CST, 2 hours 48 minutes earlier.

Area forecast discussion, Jan 21, 3:06 PM CST, 2 hours 48 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
306 PM CST THU JAN 21 2010

.DISCUSSION...
CURRENT...TOR WATCH IN EFFECT W 1/3 TIL 23Z...BUT SOME CELLS
LOOKING SEVERE TO THE E AS WELL...AS DRY SLOTTING AND SOME COOLING
TAKES PLACE AT MID LEVELS. TEMPS IN MID 50S TO LOWER 60S.

WILL KEEP MENTION OF SEVERE IN ZONES THRU 03Z...AFTER WHICH UPPER LO
(MOVING NE) OUTRUNS SURFACE LO AND WE LOSE OUR DYNAMIC SUPPORT.
WINDS HAVE GONE SOUTHERLY SO VEERING NOT QUITE AS STRONG...WOULD
SUSPECT MAINLY A HAIL THREAT BY EVE.

ASSCD SURFACE FRONT EXPECTED TO BE NEAR HOP BY 06Z TONITE...AND
NEAR PLATEAU BY 12Z. WILL CARRY HI CHANCE POPS (50%) FOR TONITE.
LO CLOUDS WILL LINGER IN AREA FOR QUITE SOME TIME...MAYBE INTO SAT.

SOME MORE RAIN ON HORIZON FOR SAT NITE AND SUN...AND ESF MENTIONS
POSSIBLE FLOOD PROBLEMS. STRONG FRONT MOVES E AS SURFACE LO
DEVELOPS OVER CNTRL PLAINS SAT...CHANCE RW- FAR W.

PRE-FRONTAL SQUALL LINE EXPECTED TO MOVE ACROSS SAT NITE AND THEN
OCCLUDED FRONT MOVES ACROSS SUN AFTERNOON OR EVE. SOME WRAP-AROUND
LO CHANCE FLURRIES/R- MON NITE AND TUE. BACK TO NEAR SEASONAL
TEMPS MON AND BEYOND.

BY THU...GFS DEVELOPS A SURFACE LO OVER E TX WITH A STRONG COLD FRONT
WITH MUCH COLDER AIR MOVING SE. DGEX EVEN FASTER WITH THIS
FEATURE...WHILE EURO SUPPRESES LO WELL TO SW. WILL GO WITH 50%
POPS FOR R- FOR NOW.
&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      45  52  43  61 /  50   0  10  10
CLARKSVILLE    42  48  41  59 /  50   0  10  30
CROSSVILLE     45  49  38  55 /  50  20  10  10
COLUMBIA       47  52  42  60 /  50   0  10  10
LAWRENCEBURG   47  51  42  61 /  50   0  10  10
WAVERLY        43  50  42  60 /  50   0  10  40
&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

17/MAG

Hazardous weather outlook, Jan 21, 9:06 AM CST, 8 hours 48 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NASHVILLE TN
906 AM CST THU JAN 21 2010

TNZ005>011-022>034-056>066-075-077>080-093>095-221130-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
HOUSTON-HUMPHREYS-DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-
SMITH-JACKSON-PUTNAM-OVERTON-FENTRESS-PERRY-HICKMAN-LEWIS-
WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DEKALB-WHITE-
CUMBERLAND-BEDFORD-COFFEE-WARREN-GRUNDY-VAN BUREN-WAYNE-LAWRENCE-
GILES-
906 AM CST THU JAN 21 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT

THERE IS A SLIGHT CHANCE OF SEVERE THUNDERSTORMS TODAY. THEY WILL BE
MOST FAVORABLE IN THE LATE MORNING AND AFTERNOON. LARGE HAIL AND
DAMAGING WINDS ARE THE MAIN THREAT BUT THE ATMOSPHERE WILL BECOME
CONDUCIVE FOR ISOLATED TORNADOES AS WELL.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER AND EMERGENCY MANAGER ACTIVATION MAY BE NEEDED.

17/MAG

In the hours before

Special weather statement, Jan 21, 4:53 PM CST, 1 hour 1 minute before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
453 PM CST THU JAN 21 2010

TNZ027-059-212330-
DAVIDSON-WILLIAMSON-
453 PM CST THU JAN 21 2010

...SIGNIFICANT WEATHER ADVISORY FOR DAVIDSON AND WILLIAMSON
COUNTIES...

AT 450 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR FAIRVIEW...OR 13 MILES WEST OF FRANKLIN...
MOVING NORTHEAST AT 50 MPH.

THIS STORM WILL BE NEAR...
  6 MILES NORTHWEST OF FRANKLIN BY 505 PM CST.
  FOREST HILLS BY 510 PM CST.
  OAK HILL BY 515 PM CST.

NICKEL SIZE HAIL IS EXPECTED WITH THIS STORM.

ROSE

Local storm report, Jan 21, 5:11 PM CST, 43 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
511 PM CST THU JAN 21 2010

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0455 PM     HAIL             9 N MCMINNVILLE         35.82N 85.78W
01/21/2010  E1.00 INCH       WARREN             TN   PUBLIC

&&

MD

Special weather statement, Jan 21, 5:21 PM CST, 33 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
521 PM CST THU JAN 21 2010

TNZ007-008-026-212345-
CHEATHAM-ROBERTSON-SUMNER-
521 PM CST THU JAN 21 2010

...SIGNIFICANT WEATHER ADVISORY FOR CHEATHAM...ROBERTSON AND SUMNER
COUNTIES...

AT 519 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A CLUSTER OF STRONG THUNDERSTORMS 6 MILES SOUTHWEST OF
SPRINGFIELD...MOVING NORTHEAST AT 25 MPH.

THIS STORM WILL BE NEAR...
  SPRINGFIELD BY 535 PM CST.
  6 MILES WEST OF CROSS PLAINS BY 545 PM CST.

NICKEL SIZE HAIL IS EXPECTED WITH THIS STORM.

ROSE

Special weather statement, Jan 21, 5:24 PM CST, 30 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
524 PM CST THU JAN 21 2010

TNZ010-011-032>034-220030-
CLAY-FENTRESS-OVERTON-PICKETT-PUTNAM-
524 PM CST THU JAN 21 2010

...SIGNIFICANT WEATHER ADVISORY FOR CLAY...FENTRESS...OVERTON...
PICKETT AND PUTNAM COUNTIES UNTIL 630 PM...

AT 519 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
STRONG THUNDERSTORMS NEAR LIVINGSTON...MOVING NORTHEAST AT 35 MPH.

PEOPLE IN EASTERN CLAY...FENTRESS...NORTHERN PUTNAM...OVERTON AND
PICKETT COUNTIES...INCLUDING THE CITY OF BYRDSTOWN...SHOULD MONITOR
THE WEATHER SITUATION CLOSELY. LISTEN FOR POSSIBLE WARNINGS AND BE
PREPARED TO TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN.

HALF INCH SIZE HAIL IS EXPECTED WITH THESE STORMS.

13

Local storm report, Jan 21, 5:47 PM CST, 7 minutes before

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Local storm report, Jan 21, 5:53 PM CST, 1 minute before

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      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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      <p id="message2">
        Please try again in a few minutes.
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The office that day

Everything else NWS Nashville, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 20, 9:00 PM CST	River Flood Warning	OHX	Bedford	12 hr
Jan 21, 2:22 PM CST	Severe Thunderstorm Warning	OHX	Marshall, Maury	23 min
Jan 21, 2:44 PM CST	Tornado Warning	OHX	Clay, Macon, Trousdale	31 min
Jan 21, 3:08 PM CST	Severe Thunderstorm Warning	OHX	Bedford, Marshall, Rutherford, Williamson	37 min
Jan 21, 3:31 PM CST	Severe Thunderstorm Warning	OHX	DeKalb, Rutherford, Smith, Wilson	29 min
Jan 21, 3:42 PM CST	Severe Thunderstorm Warning	OHX	Cannon, Rutherford	19 min
Jan 21, 3:44 PM CST	Severe Thunderstorm Warning	OHX	Stewart	31 min
Jan 21, 3:49 PM CST	Severe Thunderstorm Warning	OHX	Giles	26 min
Jan 21, 3:49 PM CST	Severe Thunderstorm Warning	OHX	Clay, Jackson, Overton, Putnam	26 min
Jan 21, 3:53 PM CST	Severe Thunderstorm Warning	OHX	Clay, DeKalb, Jackson, Macon, Smith	37 min
Jan 21, 3:56 PM CST	Tornado Warning	OHX	Giles	34 min
Jan 21, 4:10 PM CST	Tornado Warning	OHX	Clay, Jackson, Overton, Putnam	35 min
Jan 21, 4:19 PM CST	Tornado Warning	OHX	Clay, Overton, Pickett	26 min
Jan 21, 4:25 PM CST	Severe Thunderstorm Warning	OHX	Cannon, DeKalb, Warren, White	35 min
Jan 21, 4:28 PM CST	Tornado Warning	OHX	Giles, Lawrence, Maury	32 min
Jan 21, 4:42 PM CST	Severe Thunderstorm Warning	OHX	Clay, Fentress, Overton, Pickett, Putnam	33 min
Jan 21, 4:58 PM CST	Severe Thunderstorm Warning	OHX	White	14 min
Jan 21, 5:02 PM CST	Tornado Warning	OHX	Bedford, Giles, Marshall, Maury	28 min
Jan 21, 5:10 PM CST	Tornado Warning	OHX	Grundy	35 min
Jan 21, 5:27 PM CST	Tornado Warning	OHX	Bedford, Marshall	18 min
Jan 21, 5:39 PM CST	Severe Thunderstorm Warning	OHX	Coffee, Grundy	36 min
Jan 21, 5:46 PM CST	Severe Thunderstorm Warning	OHX	Bedford	14 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2010 Every severe thunderstorm warning in 2010

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.