Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 6, NWS Norman, OK

February 28, 2021Bryan County, Marshall County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Feb 28, 2021, 10:02 AM CST for Bryan County, Marshall County, Oklahoma. It was in force for 43 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
Feb 28, 2021, 10:02 AM CST (16:02 UTC)
Expired
Feb 28, 2021, 10:45 AM CST
In force
43 min
Issued by
NWS Norman, OK
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Bryan County, OK, Marshall County, OK

The radar

The Dallas/Ft Worth radar (KFWS), 162 km from the middle of the area, began a volume at 16:04 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

Fort Worth, TX (KFWD), launched 12:00Z, 4.0 hours before the alert went out and 136 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, Fort Worth, TX at 12:00Z on 2021-02-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1316 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, Fort Worth, TX at 12:00Z on 2021-02-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 165 square meters per square second.1939587897117Sfc1 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
1316 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
165 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
1.2
Supercell composite
3.6

Open this sounding in Storm Lab

The text

As transmitted.

876 
WUUS54 KOUN 281602
SVROUN
OKC013-095-281645-
/O.NEW.KOUN.SV.W.0006.210228T1602Z-210228T1645Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
1002 AM CST Sun Feb 28 2021

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Bryan County in southeastern Oklahoma...
  Southeastern Marshall County in southeastern Oklahoma...

* Until 1045 AM CST.

* At 1001 AM CST, a severe thunderstorm was located over southeastern
  Lake Texoma, moving northeast at 50 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...
  Durant, Colbert, Caddo, Bokchito, Achille, Kemp, Armstrong,
  Hendrix, Cartwright, Blue, Utica, Albany, eastern Lake Texoma,
  Calera and Wade.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

If on or near eastern Lake Texoma, get away from the water and move 
indoors or inside a vehicle. Remember, lightning can strike out to 
15 miles from the parent thunderstorm. If you can hear thunder, you 
are close enough to be struck by lightning. Move to safe shelter 
now!  Do not be caught on the water in a thunderstorm.

&&

LAT...LON 3384 9614 3375 9641 3378 9644 3377 9650
      3382 9653 3382 9658 3385 9667 3383 9672
      3386 9674 3389 9668 3387 9668 3385 9663
      3389 9659 3390 9663 3391 9665 3416 9624
      3389 9596
TIME...MOT...LOC 1601Z 243DEG 43KT 3383 9660 

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

03
3 follow-up statements
334 
WWUS54 KOUN 281616
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
1016 AM CST Sun Feb 28 2021

OKC013-095-281645-
/O.CON.KOUN.SV.W.0006.000000T0000Z-210228T1645Z/
Bryan OK-Marshall OK-
1016 AM CST Sun Feb 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM CST
FOR BRYAN AND SOUTHEASTERN MARSHALL COUNTIES...

At 1014 AM CST, a severe thunderstorm was located 4 miles northeast
of Achille, moving northeast at 45 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...
Durant, Colbert, Caddo, Bokchito, Achille, Kemp, Armstrong, Hendrix,
Cartwright, Blue, Utica, Albany, eastern Lake Texoma, Calera and
Wade.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 3384 9614 3375 9641 3378 9644 3377 9650
      3382 9653 3382 9658 3385 9667 3383 9672
      3386 9674 3389 9668 3387 9668 3385 9663
      3389 9659 3390 9663 3391 9665 3416 9624
      3389 9596
TIME...MOT...LOC 1614Z 239DEG 41KT 3388 9633 

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

03
295 
WWUS54 KOUN 281631
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
1031 AM CST Sun Feb 28 2021

OKC095-281641-
/O.CAN.KOUN.SV.W.0006.000000T0000Z-210228T1645Z/
Marshall OK-
1031 AM CST Sun Feb 28 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MARSHALL 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 3384 9614 3390 9634 3401 9632 3409 9616
      3389 9596
TIME...MOT...LOC 1631Z 249DEG 51KT 3396 9603 

$$

OKC013-281645-
/O.CON.KOUN.SV.W.0006.000000T0000Z-210228T1645Z/
Bryan OK-
1031 AM CST Sun Feb 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM CST
FOR CENTRAL BRYAN COUNTY...

At 1031 AM CST, a severe thunderstorm was located near Bennington,
moving northeast at 55 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

Locations impacted include...
Bokchito, Utica, Blue, Albany and Wade. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

&&

LAT...LON 3384 9614 3390 9634 3401 9632 3409 9616
      3389 9596
TIME...MOT...LOC 1631Z 249DEG 51KT 3396 9603 

HAIL...1.50IN
WIND...60MPH
 
$$

03
547 
WWUS54 KOUN 281641
SVSOUN

Severe Weather Statement
National Weather Service Norman OK
1041 AM CST Sun Feb 28 2021

OKC013-281650-
/O.EXP.KOUN.SV.W.0006.000000T0000Z-210228T1645Z/
Bryan OK-
1041 AM CST Sun Feb 28 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BRYAN COUNTY WILL
EXPIRE AT 1045 AM CST...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

Remember, a Severe Thunderstorm Warning still remains in effect for
extreme eastern Bryan County.

LAT...LON 3384 9614 3390 9634 3401 9632 3409 9616
      3389 9596
TIME...MOT...LOC 1640Z 243DEG 43KT 3400 9592 

$$

03

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 27, 9:08 PM CSTDense Fog AdvisoryOUNAtoka, Blaine, Bryan, Caddo, Canadian, Carter and 22 more8 hr
Feb 28, 9:49 AM CSTSpecial Weather StatementOUNBryan41 min
Feb 28, 10:29 AM CSTSevere Thunderstorm WarningOUNAtoka, Bryan26 min
Feb 28, 10:53 AM CSTSpecial Weather StatementOUNBryan52 min
Feb 28, 11:25 AM CSTSpecial Weather StatementOUNBryan20 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.