Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 59, NWS Norman, OK

April 9, 2021Greer County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 9, 2021, 3:28 PM CDT for Greer County, Oklahoma. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 9, 2021, 3:28 PM CDT (20:28 UTC)
Expired
Apr 9, 2021, 3:51 PM CDT
In force
23 min
Issued by
NWS Norman, OK
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Greer County, OK

The radar

The Altus AFB radar (KFDR), 84 km from the middle of the area, began a volume at 20:30 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 nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 8.5 hours before the alert went out and 193 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-pSkew-T log-p diagram, Amarillo Airport, TX at 12:00Z on 2021-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Amarillo Airport, TX at 12:00Z on 2021-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -45 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3442 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
-45 m²/s²
0-3 km storm-relative helicity
16 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

297 
WUUS54 KOUN 092028
SVROUN
OKC055-092115-
/O.NEW.KOUN.SV.W.0059.210409T2028Z-210409T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
328 PM CDT Fri Apr 9 2021

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Central Greer County in southwestern Oklahoma...

* Until 415 PM CDT.

* At 328 PM CDT, a severe thunderstorm was located 11 miles northeast
  of Vinson, moving southeast at 25 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Mangum and Hester. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3508 9970 3491 9934 3478 9943 3472 9955
      3473 9957 3473 9959 3492 9973 3494 9973
      3495 9975 3499 9978
TIME...MOT...LOC 2028Z 315DEG 21KT 3500 9970 

HAIL...1.00IN
WIND...60MPH
 
$$

Mahale
2 follow-up statements
932 
WWUS54 KOUN 092037
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
337 PM CDT Fri Apr 9 2021

OKC055-092115-
/O.CON.KOUN.SV.W.0059.000000T0000Z-210409T2115Z/
Greer OK-
337 PM CDT Fri Apr 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM CDT
FOR CENTRAL GREER COUNTY...

At 337 PM CDT, a severe thunderstorm was located 9 miles northwest of
Mangum, moving southeast at 25 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Mangum and Hester. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3491 9934 3478 9943 3472 9955 3473 9957
      3473 9959 3492 9973 3494 9973 3495 9975
      3503 9959
TIME...MOT...LOC 2037Z 314DEG 21KT 3495 9964 

HAIL...1.00IN
WIND...60MPH
 
$$

Mahale
565 
WWUS54 KOUN 092051
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
351 PM CDT Fri Apr 9 2021

OKC055-092101-
/O.CAN.KOUN.SV.W.0059.000000T0000Z-210409T2115Z/
Greer OK-
351 PM CDT Fri Apr 9 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL GREER COUNTY IS
CANCELLED...
                 
The storm which prompted the warning has weakened below severe
limits, therefore the warning has been cancelled.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 3491 9934 3478 9943 3472 9955 3473 9957
      3473 9959 3492 9973 3494 9973 3495 9975
      3503 9959
TIME...MOT...LOC 2050Z 315DEG 21KT 3489 9957 

$$

Mahale

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 9, 2:57 AM CDTWind AdvisoryOUNAlfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 31 more20 hr
Apr 9, 10:21 AM CDTSpecial Weather StatementOUNBryan24 min
Apr 9, 10:32 AM CDTSpecial Weather StatementOUNBryan28 min
Apr 9, 3:21 PM CDTSpecial Weather StatementOUNGreer24 min
Apr 9, 3:35 PM CDTSpecial Weather StatementOUNWashita40 min
Apr 9, 3:39 PM CDTSpecial Weather StatementOUNKingfisher36 min
Apr 9, 3:49 PM CDTSpecial Weather StatementOUNCanadian26 min
Apr 9, 3:52 PM CDTSpecial Weather StatementOUNGreer23 min
Apr 9, 3:57 PM CDTSevere Thunderstorm WarningOUNCaddo, Canadian, Grady48 min
Apr 9, 4:12 PM CDTSpecial Weather StatementOUNLogan33 min
Apr 9, 4:13 PM CDTSpecial Weather StatementOUNWashita32 min
Apr 9, 4:23 PM CDTSpecial Weather StatementOUNGrant37 min
Apr 9, 4:25 PM CDTSevere Thunderstorm WarningOUNLogan, Payne50 min
Apr 9, 4:29 PM CDTSevere Thunderstorm WarningOUNKiowa, Washita16 min
Apr 9, 4:36 PM CDTSevere Thunderstorm WarningOUNCaddo, Canadian, Grady39 min
Apr 9, 4:52 PM CDTSpecial Weather StatementOUNKingfisher23 min
Apr 9, 4:53 PM CDTSevere Thunderstorm WarningOUNKingfisher52 min
Apr 9, 5:06 PM CDTSevere Thunderstorm WarningOUNGrady39 min
Apr 9, 5:17 PM CDTSevere Thunderstorm WarningOUNLogan, Noble, Payne43 min
Apr 9, 5:18 PM CDTSevere Thunderstorm WarningOUNKingfisher, Logan, Oklahoma42 min
Apr 9, 5:25 PM CDTSevere Thunderstorm WarningOUNLincoln, Logan, Payne50 min
Apr 9, 5:31 PM CDTSevere Thunderstorm WarningOUNGrady, McClain44 min
Apr 9, 5:36 PM CDTSpecial Weather StatementOUNPottawatomie24 min
Apr 9, 5:39 PM CDTSpecial Weather StatementOUNLincoln36 min
Apr 9, 5:48 PM CDTSpecial Weather StatementOUNLincoln27 min
Apr 9, 5:51 PM CDTSevere Thunderstorm WarningOUNPottawatomie, Seminole39 min
Apr 9, 5:57 PM CDTSevere Thunderstorm WarningOUNLincoln, Logan, Oklahoma48 min
Apr 9, 6:05 PM CDTSevere Thunderstorm WarningOUNGarvin, Grady, McClain, Stephens40 min
Apr 9, 6:09 PM CDTSpecial Weather StatementOUNLincoln36 min
Apr 9, 6:22 PM CDTSevere Thunderstorm WarningOUNPottawatomie, Seminole27 min
Apr 9, 6:34 PM CDTSevere Thunderstorm WarningOUNLincoln56 min
Apr 9, 6:38 PM CDTSpecial Weather StatementOUNPottawatomie52 min
Apr 9, 6:58 PM CDTSpecial Weather StatementOUNPottawatomie, Seminole47 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2021Every severe thunderstorm warning in 2021

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.