Alert archive / Tennessee / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 20, NWS Nashville, TN

April 3, 2007Cheatham County, Robertson County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Apr 3, 2007, 8:06 PM CDT for Cheatham County, Robertson County, Tennessee. It was in force for 39 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: Apr 3, 2007, 8:06 PM CDT (01:06 UTC)
Expired: Apr 3, 2007, 8:45 PM CDT
In force: 39 min
Issued by: NWS Nashville, TN
Area: Counties, with a storm outline in the text

Counties Cheatham County, TN, Robertson County, TN

What was reported inside it

Time	Report	Where	Remark
Apr 3, 8:21 PM CDT	HAIL 1	8 Se Springfield, TN	SPOTTER REPORTS QUARTER SIZE HAIL AT 821 CDT. REPORT RECEIVED AT 1015 PM CDT.

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 15 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 watch it was issued in

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

Issued	Product	Office	Lasted
Apr 3, 2:15 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Apr 3, 8:03 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 1.1 hours before the alert went out and 53 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: 1678 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 1714 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 200 m²/s²
0-3 km storm-relative helicity: 261 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 10.5

Open this sounding in Storm Lab

The text

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

000 
WUUS54 KOHX 040107
SVROHX
TNC021-147-040145-
/O.NEW.KOHX.SV.W.0020.070404T0106Z-070404T0145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NASHVILLE TN
806 PM CDT TUE APR 3 2007

THE NATIONAL WEATHER SERVICE IN NASHVILLE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN CHEATHAM COUNTY IN TENNESSEE...
  ROBERTSON COUNTY IN TENNESSEE...
  THIS INCLUDES THE CITY OF SPRINGFIELD...

* UNTIL 845 PM CDT

* AT 804 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING NICKEL SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS
  WERE LOCATED ALONG A LINE EXTENDING FROM 10 MILES NORTH OF
  SPRINGFIELD TO 12 MILES EAST OF CLARKSVILLE TO 13 MILES SOUTH OF
  CLARKSVILLE...AND MOVING EAST AT 40 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  SPRINGFIELD BY 830 PM CDT...
  CROSS PLAINS BY 840 PM CDT...
  GREENBRIER BY 845 PM CDT...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

LAT...LON 3664 8711 3650 8714 3633 8728 3632 8693
      3649 8663 3666 8653

$$
STEIGERWALDT

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 Apr 3, 4:50 PM CDT, 3 hours 16 minutes earlier.

Area forecast discussion, Apr 3, 4:50 PM CDT, 3 hours 16 minutes before

AREA FORECAST DISCUSSION...UPDATED TIMING
NATIONAL WEATHER SERVICE NASHVILLE TN
450 PM CDT TUE APR 3 2007

.DISCUSSION...
STG LOW CENTERED NEAR CHICAGO WITH A COLD FRONT STRETCHING SWWD
TO THE DALLAS AREA. FRONT IS MOVING TOWARD THE ESE AT 30 MPH.
STRONG THUNDERSTORMS ARE ARRAYED ALL ALONG THIS FRONT FROM SERN
MISSOURI NEWD. DAMAGING WINDS AND HAIL ARE EXPECTED WITH THIS
LINE OF CONVECTION AS WELL AS THE POSSIBILITY OF TORNADOES.
WHILE THERE WILL BE SCATTERED STORMS OUT AHEAD OF THE MAIN FRONT...
WE EXPECT THE ORGANIZED CONVECTION WITH THE FRONT TO ENTER NWRN
COUNTIES BETWEEN 7PM AND 8PM...INTO THE NASHVILLE AREA
AROUND 10 PM...AND CROSSVILLE AROUND 1 AM. MOST ACTIVITY SHOULD BE
OUT OF THE AREA BY 5 AM.

A STRONG SHOT OF COLD AIR BEHIND THIS FRONT WITH 850 MB TEMPS
DROPPING TO -10C BY EARLY SAT AM. THIS WILL LIKELY MEAN A
POSSIBILITY OF A FREEZE FOR THU AM THROUGH SUN AM...WITH SUN AM
BEING THE COLDEST MORNING. WILL CONSIDER LATER TONIGHT IF A FREEZE
WATCH/WARNINGS ARE NECESSARY.

&&

.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE    49  58  32  53 /  80  10  10   0
CLARKSVILLE  43  53  30  51 /  80  10  10   0
CROSSVILLE   47  56  27  49 /  80  10  10   0

&&

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

JLM

Hazardous weather outlook, Apr 3, 6:21 PM CDT, 1 hour 45 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
621 PM CDT TUE APR 3 2007

TNZ005>011-022>034-056>066-075-077>080-093>095-041200-
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-
621 PM CDT TUE APR 3 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF MIDDLE TENNESSEE.

.DAY ONE...TONIGHT

AREAS ALONG AND WEST OF INTERSTATE 65 ARE IN A MODERATE RISK FOR
SEVERE WEATHER TONIGHT. AREAS EAST OF I 65 ARE IN A SLIGHT RISK.
SEVERE THUNDERSTORMS ARE LIKELY BETWEEN 800 PM AND MIDNIGHT AHEAD
OF A VIGOROUS COLD FRONT. THE ATMOSPHERE HAS BECOME VERY
UNSTABLE...SO DAMAGING WINDS AND LARGE HAIL WILL BE LIKELY. A FEW
STORMS MAY HAVE ENOUGH ROTATION TO PRODUCE TORNADOES.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

MUCH COLDER AIR WILL BE USHERED IN BEHIND THE FRONT WEDNESDAY INTO
THE WEEKEND. A FREEZE IS LIKELY...ESPECIALLY OVER THE EASTER
WEEKEND. THIS WILL BE QUITE A SHOCK TO VEGETATION AFTER THE
PROLONGED WARM SPELL.

OVERNIGHT LOW TEMPERATURES WILL DROP DOWN TO NEAR FREEZING WEDNESDAY
NIGHT THROUGH FRIDAY NIGHT. ON SATURDAY NIGHT...AS THE ARCTIC
SURFACE HIGH BUILDS IN...A KILLING FREEZE MAY OCCUR AS TEMPERATURES
MAY DROP DOWN INTO THE MID TO UPPER 20S BY EASTER MORNING.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF SPOTTER AND EMERGENCY MANAGERS WILL BE NEEDED
THROUGH THIS EVENING.

13

In the hours before

Local storm report, Apr 3, 4:05 PM CDT, 4 hours 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
405 PM CDT TUE APR 03 2007

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

0358 PM     HAIL             ALTAMONT                35.43N 85.73W
04/03/2007  M0.75 INCH       GRUNDY             TN   COUNTY OFFICIAL

&&

JCOHEN

Local storm report, Apr 3, 4:08 PM CDT, 3 hours 58 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
408 PM CDT TUE APR 03 2007

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

0340 PM     HAIL             COALMONT                35.34N 85.71W
04/03/2007  E1.75 INCH       GRUNDY             TN   STORM CHASER

&&

JCOHEN

Local storm report, Apr 3, 4:11 PM CDT, 3 hours 55 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
411 PM CDT TUE APR 03 2007

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

0400 PM     HAIL             ALTAMONT                35.43N 85.73W
04/03/2007  E1.75 INCH       GRUNDY             TN   STORM CHASER

&&

JCOHEN

Special weather statement, Apr 3, 4:22 PM CDT, 3 hours 44 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
422 PM CDT TUE APR 3 2007

TNZ080-032145-
VAN BUREN-
422 PM CDT TUE APR 3 2007

...STRONG THUNDERSTORM MOVING ACROSS EXTREME EASTERN VAN BUREN
COUNTY...

A STRONG THUNDERSTORM WILL MOVE ACROSS THE EXTREME EASTERN PART OF
VAN BUREN COUNTY THROUGH 445 PM. HAIL UP TO THE SIZE OF DIMES WILL
BE POSSIBLE. WIND GUSTS UP TO 35 MPH WILL ALSO BE POSSIBLE.

21

Local storm report, Apr 3, 6:08 PM CDT, 1 hour 58 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
608 PM CDT TUE APR 03 2007

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

0600 PM     HAIL             13 SE CROSSVILLE        35.82N 84.87W
04/03/2007  E0.88 INCH       CUMBERLAND         TN   UNKNOWN

            PUBLIC REPORTED THE HAIL.

&&

STEIGERWALDT

Local storm report, Apr 3, 7:46 PM CDT, 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
746 PM CDT TUE APR 03 2007

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

0729 PM     HAIL             8 N DOVER               36.60N 87.84W
04/03/2007  E1.75 INCH       STEWART            TN   LAW ENFORCEMENT

            SHERIFFS OFFICE REPORTED GOLF BALL SIZE HAIL AT BUMPUS
            MILLS.

&&

ORCHANIAN

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 3, 7:15 PM CDT	Severe Thunderstorm Warning	OHX	Benton, Houston, Humphreys	60 min
Apr 3, 7:45 PM CDT	Severe Thunderstorm Warning	OHX	Montgomery, Stewart	30 min
Apr 3, 8:26 PM CDT	Severe Thunderstorm Warning	OHX	Dickson	34 min
Apr 3, 8:28 PM CDT	Severe Thunderstorm Warning	OHX	Cumberland, White	32 min
Apr 3, 8:32 PM CDT	Severe Thunderstorm Warning	OHX	Perry	28 min
Apr 3, 8:41 PM CDT	Severe Thunderstorm Warning	OHX	Hickman	49 min
Apr 3, 8:57 PM CDT	Severe Thunderstorm Warning	OHX	Davidson, Williamson, Wilson	48 min
Apr 3, 9:00 PM CDT	Severe Thunderstorm Warning	OHX	Cumberland	45 min
Apr 3, 9:07 PM CDT	Severe Thunderstorm Warning	OHX	Maury	23 min
Apr 3, 9:12 PM CDT	Tornado Warning	OHX	Cumberland	33 min
Apr 3, 9:34 PM CDT	Severe Thunderstorm Warning	OHX	Marshall, Maury	26 min
Apr 3, 9:38 PM CDT	Severe Thunderstorm Warning	OHX	Cannon, Rutherford	37 min
Apr 3, 9:44 PM CDT	Severe Thunderstorm Warning	OHX	Cumberland	31 min
Apr 3, 9:55 PM CDT	Severe Thunderstorm Warning	OHX	Bedford, Coffee	35 min
Apr 4, 2:46 AM CDT	Freeze Watch	OHX	Bedford, Benton, Cannon, Cheatham, Clay, Coffee and 33 more	24 hr
Apr 4, 2:46 AM CDT	Freeze Warning	OHX	Bedford, Benton, Cannon, Cheatham, Clay, Coffee and 33 more	29 hr

Nearby

Severe Thunderstorm Warnings in Tennessee, 2007 Every severe thunderstorm warning in 2007

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.