Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 484, NWS Norman, OK

September 7, 2021Blaine County, Custer County, Dewey County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Sep 7, 2021, 8:27 PM CDT for Blaine County, Custer County, Dewey County, Oklahoma. It was in force for 33 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
Sep 7, 2021, 8:27 PM CDT (01:27 UTC)
Expired
Sep 7, 2021, 9:00 PM CDT
In force
33 min
Issued by
NWS Norman, OK
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Blaine County, OK, Custer County, OK, Dewey County, OK

The radar

The Vance AFB radar (KVNX), 125 km from the middle of the area, began a volume at 01:27 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

Norman, OK (KOUN), launched 00:00Z, 1.5 hours before the alert went out and 139 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, Norman, OK at 00:00Z on 2021-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2037 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 00:00Z on 2021-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 square meters per square second.1939Sfc1 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
2037 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
1991 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
159 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.0

Open this sounding in Storm Lab

The text

As transmitted.

524 
WUUS54 KOUN 080127
SVROUN
OKC011-039-043-080200-
/O.NEW.KOUN.SV.W.0484.210908T0127Z-210908T0200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
827 PM CDT Tue Sep 7 2021

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Northeastern Custer County in western Oklahoma...
  Southwestern Blaine County in northwestern Oklahoma...
  Southeastern Dewey County in northwestern Oklahoma...

* Until 900 PM CDT.

* At 826 PM CDT, a severe thunderstorm was located near Thomas,
  moving south 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...
  Weatherford, Thomas, Custer City and Fay. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3587 9891 3589 9866 3556 9852 3556 9894
TIME...MOT...LOC 0126Z 350DEG 21KT 3577 9875 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

30
2 follow-up statements
197 
WWUS54 KOUN 080148
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
848 PM CDT Tue Sep 7 2021

OKC043-080158-
/O.CAN.KOUN.SV.W.0484.000000T0000Z-210908T0200Z/
Dewey OK-
848 PM CDT Tue Sep 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN DEWEY COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3579 9890 3580 9865 3557 9853 3557 9887
TIME...MOT...LOC 0148Z 342DEG 19KT 3564 9872 

$$

OKC011-039-080200-
/O.CON.KOUN.SV.W.0484.000000T0000Z-210908T0200Z/
Custer OK-Blaine OK-
848 PM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM CDT
FOR NORTHEASTERN CUSTER AND SOUTHWESTERN BLAINE COUNTIES...

At 848 PM CDT, a severe thunderstorm was located 7 miles south of
Thomas, moving south at 20 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...
Thomas and Custer City. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3579 9890 3580 9865 3557 9853 3557 9887
TIME...MOT...LOC 0148Z 342DEG 19KT 3564 9872 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

30
436 
WWUS54 KOUN 080156
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
856 PM CDT Tue Sep 7 2021

OKC011-039-080206-
/O.EXP.KOUN.SV.W.0484.000000T0000Z-210908T0200Z/
Custer OK-Blaine OK-
856 PM CDT Tue Sep 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CUSTER AND
SOUTHWESTERN BLAINE COUNTIES WILL EXPIRE AT 900 PM CDT...
                 
The storm which prompted the warning has weakened below severe
limits, therefore the warning will be allowed to expire.  However
gusty winds are still possible with this thunderstorm.

LAT...LON 3579 9890 3580 9865 3557 9853 3557 9887
TIME...MOT...LOC 0156Z 350DEG 21KT 3561 9871 

$$

30

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 7:15 PM CDTSpecial Weather StatementOUNRoger Mills30 min
Sep 7, 7:21 PM CDTSevere Thunderstorm Warning Considerable damage threatOUNBlaine, Dewey, Kingfisher, Major39 min
Sep 7, 7:43 PM CDTSpecial Weather StatementOUNNoble32 min
Sep 7, 7:51 PM CDTSevere Thunderstorm Warning Considerable damage threatOUNBlaine, Canadian, Custer, Dewey, Kingfisher39 min
Sep 7, 8:02 PM CDTSevere Thunderstorm WarningOUNLogan, Noble, Payne25 min
Sep 7, 8:21 PM CDTSpecial Weather StatementOUNCuster24 min
Sep 7, 8:46 PM CDTSpecial Weather StatementOUNCuster29 min
Sep 7, 9:11 PM CDTSpecial Weather StatementOUNBeckham34 min
Sep 7, 9:19 PM CDTSevere Thunderstorm WarningOUNBeckham, Greer41 min
Sep 7, 9:23 PM CDTSpecial Weather StatementOUNWashita37 min
Sep 7, 9:40 PM CDTSpecial Weather StatementOUNKay35 min
Sep 8, 12:40 AM CDTSpecial Weather StatementOUNCotton35 min
Sep 8, 4:55 AM CDTSpecial Weather StatementOUNBryan35 min
Sep 8, 5:31 AM CDTSpecial Weather StatementOUNBryan29 min
Sep 8, 6:10 AM CDTSpecial Weather StatementOUNBryan35 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.