Alert archive / Tennessee / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 154, NWS Nashville, TN

August 23, 2014Robertson County, Sumner County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Aug 23, 2014, 4:45 PM CDT for Robertson County, Sumner County, Tennessee. It was in force for 45 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 23, 2014, 4:45 PM CDT (21:45 UTC)
Expired: Aug 23, 2014, 5:30 PM CDT
In force: 45 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon

Counties Robertson County, TN, Sumner County, TN

The radar

The Nashville radar (KOHX), 13 km from the middle of the area, began a volume at 21:45 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.

What was reported inside it

Time	Report	Where	Remark
Aug 23, 4:52 PM CDT	TSTM WND DMG	Hendersonville, TN	TREES AND POWER LINES ARE DOWN IN HENDERSONVILLE.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 7 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 9.8 hours before the alert went out and 26 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: 204 J/kg
Mixed-layer CIN: -164 J/kg
Mixed-layer LCL: 1079 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: -11 m²/s²
0-3 km storm-relative helicity: 8 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

684 
WUUS54 KOHX 232145
SVROHX
TNC147-165-232230-
/O.NEW.KOHX.SV.W.0154.140823T2145Z-140823T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NASHVILLE TN
445 PM CDT SAT AUG 23 2014

THE NATIONAL WEATHER SERVICE IN NASHVILLE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN ROBERTSON COUNTY IN MIDDLE TENNESSEE...
  SOUTHWESTERN SUMNER COUNTY IN MIDDLE TENNESSEE...

* UNTIL 530 PM CDT

* AT 445 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH. THE STORM WAS NEAR MILLERSVILLE...MOVING SOUTH AT 10
  MPH.

* LOCATIONS IMPACTED INCLUDE...
  HENDERSONVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEEK SHELTER IN A STURDY BUILDING AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3650 8652 3634 8644 3629 8653 3631 8654
      3632 8655 3628 8656 3625 8663 3646 8674
TIME...MOT...LOC 2145Z 348DEG 8KT 3639 8660

$$

FORECASTER: 31

1 follow-up statement

445 
WWUS54 KOHX 232225
SVSOHX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
525 PM CDT SAT AUG 23 2014

TNC147-165-232236-
/O.EXP.KOHX.SV.W.0154.000000T0000Z-140823T2230Z/
ROBERTSON TN-SUMNER TN-
525 PM CDT SAT AUG 23 2014

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN SUMNER AND
SOUTHEASTERN ROBERTSON COUNTIES WILL EXPIRE AT 530 PM CDT...

LAT...LON 3650 8652 3634 8644 3629 8653 3631 8654
      3632 8655 3628 8656 3625 8663 3646 8674
TIME...MOT...LOC 2226Z 348DEG 8KT 3630 8658

$$
31

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 Aug 23, 3:03 PM CDT, 1 hour 42 minutes earlier.

Area forecast discussion, Aug 23, 3:03 PM CDT, 1 hour 42 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
303 PM CDT SAT AUG 23 2014

.DISCUSSION...
EXTENSIVE CLOUDS THIS MORNING GAVE WAY TO PCLOUDY/MSUNNY SKIES
THIS AFTERNOON ALONG WITH ISOLATED SHOWERS/STORMS. SFC DEWPOINTS
ARE A COUPLE DEGREES HIGHER THAN 24 HOURS AGO...AND WITH AIR TEMPS
MAINLY IN THE 90S...HEAT INDEX VALUES SO FAR THIS AFTERNOON HAVE
BEEN IN THE 99 TO 105 RANGE ACROSS ALL OF MIDDLE TN EXCEPT FOR
THE EAST THIRD/PLATEAU.

SHORT WAVE THAT HELPED TRIGGER MCS LAST NIGHT OVER THE NORTHERN
PLAINS WAS STILL GOING STRONG THIS AFTERNOON AS IT CRESTED THE H5
RIDGE AXIS THAT EXISTS ALONG THE MS RIVER VALLEY. WILL KEEP CHC
POPS IN FORECAST FOR MOST AREAS ALL NIGHT TONIGHT TO ACCOUNT FOR
LEFTOVER EVENING CONVECTION PLUS POTENTIAL FOR MCS REMNANTS TO
APPROACH FROM THE NORTH. WITH H5 RIDGE AXIS TO OUR WEST...STORMS
IN OUR AREA WILL MOVE TO THE SOUTH AT 10 TO 15 MPH.

H5 PATTERN WILL NOT CHANGE TOO MUCH SUNDAY OR MONDAY AS RIDGE AXIS
REMAINS TO OUR WEST WITH LIGHT NORTHERLY FLOW ALOFT. THIS
FLOW...COMBINED WITH VERY RICH MOISTURE AND STRONG INSOLATION
SHOULD RESULT IN TWO MORE DAYS LIKE TODAY...IE...HOT/HUMID WITH
20 TO 30 PERCENT POPS. TEMPS AND HUMIDITY WILL STAY HIGH ENOUGH
ON SUNDAY FOR CONTINUED BORDERLINE HEAT ADVISORY SO WILL EXTEND
THE ADVY UNTIL 02Z MONDAY. TEMPS SHOULD EDGE SLIGHTLY LOWER ON
MONDAY SO NO NEED TO EXTEND THE ADVY THAT FAR.

EXPECT SUBTLE CHANGES IN THE H5 PATTERN BY MIDWEEK AS RIDGE AXIS
BECOMES ORIENTED ALONG THE OH VALLEY RATHER THAN THE MS VALLEY.
THIS WILL SHUT OFF THE NORTHERLY MID LEVEL FLOW OVER MID TN AND
REDUCE OUR RAIN CHANCES FOR TUESDAY AND WEDNESDAY. TEMPS AND
DEWPOINTS SHOULD BE SLIGHTLY LOWER THAN CURRENT NUMBERS...BUT IT
WILL STILL BE HOT AND HUMID.

BOTH EXTENDED MODELS SHOW POTENTIAL FOR H5 WEAK TROF TO MOVE FROM
THE WESTERN U.S. TOWARD THE EASTERN U.S. DURING THE LATTER PART OF
NEXT WEEK. THIS SHOULD ALLOW TEMPS TO GRADUALLY LOWER TO NEAR
AVERAGE LEVELS FOR LATE AUGUST WHILE ALSO PROVIDING A SLIGHT
CHANCE FOR AFTERNOON/EVENING STORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE      75  95  73  92 /  30  30  30  30
CLARKSVILLE    73  95  71  93 /  30  30  20  30
CROSSVILLE     71  88  68  84 /  40  40  40  30
COLUMBIA       72  96  73  93 /  30  30  30  30
LAWRENCEBURG   72  96  72  92 /  20  30  20  30
WAVERLY        73  96  72  94 /  20  30  20  30

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 9 PM CDT SUNDAY FOR TNZ005>009-023>030-
056>064-075-077-093>095.

&&

49

Hazardous weather outlook, Aug 23, 4:24 PM CDT, 21 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
424 PM CDT SAT AUG 23 2014

TNZ005>009-023>030-056>064-075-077-093>095-241045-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-HOUSTON-HUMPHREYS-
DICKSON-CHEATHAM-DAVIDSON-WILSON-TROUSDALE-SMITH-PERRY-HICKMAN-
LEWIS-WILLIAMSON-MAURY-MARSHALL-RUTHERFORD-CANNON-DE KALB-BEDFORD-
COFFEE-WAYNE-LAWRENCE-GILES-
424 PM CDT SAT AUG 23 2014

...HEAT ADVISORY IN EFFECT UNTIL 9 PM CDT SUNDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TONIGHT.

THUNDERSTORMS WILL BE SCATTERED THROUGH THIS EVENING. A FEW STORMS
COULD BE STRONG AND CAUSE ISOLATED MINOR WIND DAMAGE. OTHERWISE IT WILL
BE WARM AND VERY MUGGY TONIGHT.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

IT WILL BE HOT AND VERY HUMID AGAIN ON SUNDAY. AFTERNOON HEAT
INDEX VALUES WILL RANGE FROM 100 TO AROUND 105 DEGREES OVER ALL OF
THE MID STATE EXCEPT FOR THE CUMBERLAND PLATEAU AREA.

MORE INFORMATION IS AVAILABLE ON THE INTERNET AT WEATHER.GOV OR
BY LISTENING TO NOAA WEATHER RADIO.

TNZ010-011-031>034-065-066-078>080-241045-
CLAY-PICKETT-JACKSON-PUTNAM-OVERTON-FENTRESS-WHITE-CUMBERLAND-
WARREN-GRUNDY-VAN BUREN-
424 PM CDT SAT AUG 23 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

49

In the hours before

Special weather statement, Aug 23, 3:38 PM CDT, 1 hour 7 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
338 PM CDT SAT AUG 23 2014

TNZ007-232115-
ROBERTSON-
338 PM CDT SAT AUG 23 2014

...SIGNIFICANT WEATHER ADVISORY FOR ROBERTSON COUNTY...

AT 338 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM NEAR SPRINGFIELD...MOVING SOUTHEAST AT 20 MPH.

NICKEL SIZE HAIL...WINDS AROUND 50 MPH....BRIEF HEAVY
DOWNPOURS...ALONG WITH NUMEROUS CLOUD TO GROUND LIGHTNING STRIKES
ARE POSSIBLE WITH THIS STORM.

LAT...LON 3653 8694 3639 8682 3637 8687 3637 8688
      3639 8690 3638 8695 3649 8705

31

Local storm report, Aug 23, 3:59 PM CDT, 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
359 PM CDT SAT AUG 23 2014

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

0339 PM     TSTM WND DMG     3 SW SPRINGFIELD        36.47N  86.92W
08/23/2014                   ROBERTSON          TN   EMERGENCY MNGR

            EMERGENCY MANAGEMENT REPORTED A FREW TREES DOWN ON
            HEADS CHURCH RD.

&&

EVENT NUMBER OHX1400563

10

Special weather statement, Aug 23, 4:06 PM CDT, 39 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
406 PM CDT SAT AUG 23 2014

TNZ007-008-232145-
ROBERTSON-SUMNER-
406 PM CDT SAT AUG 23 2014

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

AT 405 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM NEAR CROSS PLAINS...MOVING EAST AT 10 MPH.

SOME LOCATIONS IN THE PATH INCLUDE ORLINDA...CROSS PLAINS...BLACK
JACK AND MITCHELLVILLE.

WINDS 40 TO 50 MPH ARE EXPECTED WITH THIS STORM WHICH MIGHT CAUSE
SMALL TREES TO FALL DOWN...BRIEF HEAVY DOWNPOURS...AND NUMEROUS
CLOUD TO GROUND LIGHTNING STRIKES.

LAT...LON 3665 8658 3664 8657 3665 8653 3665 8649
      3644 8662 3651 8680 3665 8674 3666 8673

31

Special weather statement, Aug 23, 4:27 PM CDT, 18 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
427 PM CDT SAT AUG 23 2014

TNZ024-057-232200-
HICKMAN-HUMPHREYS-
427 PM CDT SAT AUG 23 2014

...SIGNIFICANT WEATHER ADVISORY FOR HICKMAN AND HUMPHREYS COUNTIES...

AT 426 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM 10 MILES NORTHWEST OF CENTERVILLE...MOVING
SOUTHEAST AT 10 MPH.

SOME LOCATIONS IN THE PATH INCLUDE NUNNELLY AND CENTERVILLE.

NICKEL SIZE HAIL...WINDS 40 TO 50 MPH ARE EXPECTED WITH THIS STORM
WHICH MIGHT CAUSE SMALL TREES TO FALL DOWN...BRIEF HEAVY
DOWNPOURS...AND NUMEROUS CLOUD TO GROUND LIGHTNING STRIKES.

LAT...LON 3600 8759 3582 8722 3561 8766 3577 8773
      3584 8772 3584 8777 3588 8779

31

Local storm report, Aug 23, 4:29 PM CDT, 16 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
429 PM CDT SAT AUG 23 2014

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

0425 PM     LIGHTNING        NASHVILLE               36.17N  86.78W
08/23/2014                   DAVIDSON           TN   EMERGENCY MNGR

            LIGHTNING STRUCK A TRANSFORMER AT 7867 STEEPLECHASE
            LANE...CAUSING A FIRE

&&

EVENT NUMBER OHX1400564

MROSE

Special weather statement, Aug 23, 4:39 PM CDT, 6 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
439 PM CDT SAT AUG 23 2014

TNZ023>027-057-059-232200-
CHEATHAM-DAVIDSON-DICKSON-HICKMAN-HOUSTON-HUMPHREYS-WILLIAMSON-
439 PM CDT SAT AUG 23 2014

...SIGNIFICANT WEATHER ADVISORY FOR CHEATHAM...DAVIDSON...DICKSON...
HICKMAN...HOUSTON...HUMPHREYS AND WILLIAMSON COUNTIES...

AT 434 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A LINE OF STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM MCEWEN TO
NEAR DICKSON...AND FRANKLIN...MOVING SOUTH AT 15 MPH.

SOME LOCATIONS IN THE PATH INCLUDE NATCHEZ TRACE AT HIGHWAY 96...
KINGSTON SPRINGS...WHITE BLUFF...CHARLOTTE...DICKSON...FRANKLIN...
BURNS...FAIRVIEW...MCEWEN...LEIPERS FORK...BON AQUA AND THOMPSONS
STATION.

WIND GUSTS TO AROUND 40 MPH ARE EXPECTED WITH THESE STORMS...ALONG
WITH TORRENTIAL DOWNPOURS...AND DANGEROUS LIGHTNING STRIKES.

LAT...LON 3601 8662 3572 8670 3606 8778 3632 8762

19

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 23, 5:23 AM CDT	Heat Advisory	OHX	Bedford, Cannon, Cheatham, Coffee, Davidson, DeKalb and 21 more	40 hr
Aug 23, 3:14 PM CDT	Special Weather Statement	OHX	Cheatham	46 min
Aug 23, 3:24 PM CDT	Special Weather Statement	OHX	Houston, Humphreys, Stewart	36 min
Aug 23, 3:35 PM CDT	Special Weather Statement	OHX	Dickson	40 min
Aug 23, 3:38 PM CDT	Special Weather Statement	OHX	Robertson	37 min
Aug 23, 4:06 PM CDT	Special Weather Statement	OHX	Sumner	39 min
Aug 23, 4:10 PM CDT	Severe Thunderstorm Warning	OHX	Robertson, Sumner	35 min
Aug 23, 4:16 PM CDT	Severe Thunderstorm Warning	OHX	Robertson, Sumner	44 min
Aug 23, 4:27 PM CDT	Special Weather Statement	OHX	Hickman	33 min
Aug 23, 4:31 PM CDT	Severe Thunderstorm Warning	OHX	Macon, Sumner	29 min
Aug 23, 4:33 PM CDT	Severe Thunderstorm Warning	OHX	Hickman, Humphreys	27 min
Aug 23, 4:39 PM CDT	Special Weather Statement	OHX	Dickson, Williamson	21 min
Aug 23, 5:03 PM CDT	Special Weather Statement	OHX	Hickman, Perry, Williamson	42 min
Aug 23, 5:14 PM CDT	Special Weather Statement	OHX	Wilson	31 min
Aug 23, 5:37 PM CDT	Special Weather Statement	OHX	Hickman, Lewis, Maury, Perry, Rutherford	38 min
Aug 23, 5:51 PM CDT	Special Weather Statement	OHX	Cannon, Rutherford, Wilson	39 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2014 Every severe thunderstorm warning in 2014

Sources

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