Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 21, NWS Norman, OK

March 11, 2007Stephens County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Mar 11, 2007, 6:01 PM CDT for Stephens County, Oklahoma. It was in force for 29 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: Mar 11, 2007, 6:01 PM CDT (23:01 UTC)
Expired: Mar 11, 2007, 6:30 PM CDT
In force: 29 min
Issued by: NWS Norman, OK
Area: Counties, with a storm outline in the text

County Stephens County, OK

The radar

The Altus AFB radar (KFDR), 86 km from the middle of the area, began a volume at 23:02 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
Mar 11, 6:25 PM CDT	HAIL 0.75	6 S Duncan, OK

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

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 11.0 hours before the alert went out and 105 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: 235 J/kg
Mixed-layer CIN: -113 J/kg
Mixed-layer LCL: 861 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 196 m²/s²
0-3 km storm-relative helicity: 152 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

000 
WUUS54 KOUN 112301
SVROUN
OKC137-112330-
/O.NEW.KOUN.SV.W.0021.070311T2301Z-070311T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
601 PM CDT SUN MAR 11 2007

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  STEPHENS COUNTY IN SOUTHERN OKLAHOMA...

* UNTIL 630 PM CDT

* AT 601 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 5 MILES EAST OF CORUM...MOVING NORTH AT 20 MPH.
  HAIL UP TO THE SIZE OF QUARTERS REMAINS LIKELY.

* LOCATIONS IN THE WARNING INCLUDE CORUM...DUNCAN AND EMPIRE CITY.

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH NO ADVANCE WARNING.
MOVE IMMEDIATELY TO A STORM SHELTER... BASEMENT OR STURDY BUILDING IF
A TORNADO IS SIGHTED.

LAT...LON 3436 9813 3436 9799 3457 9789 3456 9810

$$

JAMES

1 follow-up statement

000 
WWUS54 KOUN 112315
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
614 PM CDT SUN MAR 11 2007

OKC137-112330-
/O.CON.KOUN.SV.W.0021.000000T0000Z-070311T2330Z/
STEPHENS OK-
614 PM CDT SUN MAR 11 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM CDT
FOR STEPHENS COUNTY...

AT 614 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR DETECTED A 
SEVERE THUNDERSTORM BETWEEN COMANCHE AND SUNRAY...MOVING NORTH 
NORTHEAST AT 15 MPH. HALF DOLLAR SIZE HAIL IS LIKELY.

* LOCATIONS IN THE WARNING INCLUDE DUNCAN AND EMPIRE CITY.

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH NO ADVANCE WARNING.
MOVE IMMEDIATELY TO A STORM SHELTER... BASEMENT OR STURDY BUILDING IF
A TORNADO IS SIGHTED.

LAT...LON 3436 9813 3436 9799 3457 9789 3456 9810

$$

JAMES

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 10, 7:58 PM CST	Severe Thunderstorm Warning	OUN	Ellis	62 min
Mar 11, 1:11 AM CST	Severe Thunderstorm Warning	OUN	Jackson	49 min
Mar 11, 1:53 AM CST	Severe Thunderstorm Warning	OUN	Jackson, Kiowa, Tillman	52 min
Mar 11, 4:53 PM CDT	Severe Thunderstorm Warning	OUN	Jefferson	37 min
Mar 11, 5:22 PM CDT	Severe Thunderstorm Warning	OUN	Stephens	38 min
Mar 11, 6:29 PM CDT	Severe Thunderstorm Warning	OUN	Stephens	28 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 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; radar from the NEXRAD Level II archive.