Alert archive / Tennessee / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 331, NWS Nashville, TN

August 9, 2012Sumner County, Wilson County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Aug 9, 2012, 9:45 AM CDT for Sumner County, Wilson County, Tennessee. It was in force for 15 min. 2 reports 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 9, 2012, 9:45 AM CDT (14:45 UTC)
Expired: Aug 9, 2012, 10:00 AM CDT
In force: 15 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon

Counties Sumner County, TN, Wilson County, TN

The radar

The Nashville radar (KOHX), 8 km from the middle of the area, began a volume at 14:47 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 9, 9:50 AM CDT	TSTM WND DMG	4 Ne Gallatin, TN	SEVERAL TREES DOWN ON ROCKBRIDGE ROAD NEAR 31E.
Aug 9, 9:50 AM CDT	HAIL 0.5	Gallatin, TN	REPORTED VIA FACEBOOK

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

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 2.8 hours before the alert went out and 22 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: 2387 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 1138 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 14 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

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

919 
WUUS54 KOHX 091445
SVROHX
TNC165-189-091500-
/O.NEW.KOHX.SV.W.0331.120809T1445Z-120809T1500Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NASHVILLE TN
945 AM CDT THU AUG 9 2012

THE NATIONAL WEATHER SERVICE IN NASHVILLE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN SUMNER COUNTY IN MIDDLE TENNESSEE...
  NORTHWESTERN WILSON COUNTY IN MIDDLE TENNESSEE...

* UNTIL 1000 AM CDT

* AT 943 AM CDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH. THE STORM WAS NEAR HENDERSONVILLE...MOVING NORTH AT 45
  MPH.

* LOCATIONS IMPACTED INCLUDE...
  GALLATIN...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

VERY HEAVY RAIN WILL ALSO OCCUR WITH THIS SEVERE THUNDERSTORM...WHICH
COULD FLOOD LOW LYING AREAS QUICKLY AND COVER ROADS WITH WATER. DO
NOT DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 3644 8632 3620 8650 3623 8659 3624 8660
      3624 8662 3626 8664 3628 8665 3653 8662
TIME...MOT...LOC 1445Z 201DEG 39KT 3631 8651

$$

FORECASTER: ROSE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 7:34 AM CDT	Special Weather Statement	OHX	Sumner	26 min
Aug 9, 8:29 AM CDT	Areal Flood Advisory	OHX	Robertson, Sumner	3 hr
Aug 9, 9:12 AM CDT	Severe Thunderstorm Warning	OHX	Davidson, Rutherford, Wilson	33 min
Aug 9, 9:19 AM CDT	Special Weather Statement	OHX	Robertson, Sumner	86 min
Aug 9, 9:58 AM CDT	Severe Thunderstorm Warning	OHX	Macon, Sumner, Trousdale, Wilson	17 min
Aug 9, 10:13 AM CDT	Severe Thunderstorm Warning	OHX	Macon, Sumner, Trousdale	17 min
Aug 9, 11:29 AM CDT	Special Weather Statement	OHX	Putnam, Van Buren, White	61 min
Aug 9, 11:34 AM CDT	Severe Thunderstorm Warning	OHX	Cumberland, Putnam, White	26 min
Aug 9, 11:38 AM CDT	Special Weather Statement	OHX	Coffee	37 min
Aug 9, 11:48 AM CDT	Flash Flood Warning	OHX	Coffee	2 hr
Aug 9, 11:56 AM CDT	Flash Flood Warning	OHX	Putnam, Van Buren, White	3 hr
Aug 9, 12:23 PM CDT	Flash Flood Warning	OHX	Cumberland	3 hr

Nearby

Severe Thunderstorm Warnings in Tennessee, 2012 Every severe thunderstorm warning in 2012

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.