Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 481, NWS Norman, OK

September 7, 20214 counties in Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Sep 7, 2021, 7:21 PM CDT for 4 counties in Oklahoma. It was in force for 39 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: Sep 7, 2021, 7:21 PM CDT (00:21 UTC)
Expired: Sep 7, 2021, 8:00 PM CDT
In force: 39 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Damage threat: Considerable
Hail: 1.5 in
Wind: 70.0 mph

Counties Blaine County, OK, Dewey County, OK, Kingfisher County, OK, Major County, OK

The radar

The Vance AFB radar (KVNX), 84 km from the middle of the area, began a volume at 00:21 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
Sep 7, 7:30 PM CDT	TSTM WND GST 70	Longdale, OK
Sep 7, 7:55 PM CDT	HAIL 1	4 Nw Oakwood, 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 00:00Z, 0.4 hours before the alert went out and 151 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: 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.

568 
WUUS54 KOUN 080021
SVROUN
OKC011-043-073-093-080100-
/O.NEW.KOUN.SV.W.0481.210908T0021Z-210908T0100Z/

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

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Northwestern Kingfisher County in central Oklahoma...
  Northern Blaine County in northwestern Oklahoma...
  Eastern Dewey County in northwestern Oklahoma...
  Southern Major County in northwestern Oklahoma...

* Until 800 PM CDT.

* At 721 PM CDT, severe thunderstorms were located along a line
  extending from 4 miles southeast of Isabella to near Longdale to 4
  miles southwest of Seiling, moving south at 20 mph.

  HAZARD...70 mph wind gusts and ping pong ball size hail.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           considerable tree damage. Wind damage is also likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Watonga, Fairview, Taloga, Okeene, Seiling, Canton, Longdale, Ames,
  Hitchcock, Oakwood, Putnam, Canton Lake, Orion, Eagle City,
  Isabella, Homestead, Hucmac and Southard.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3628 9821 3601 9805 3583 9845 3581 9911
      3615 9906 3616 9901 3616 9896 3618 9896
      3629 9851
TIME...MOT...LOC 0021Z 352DEG 16KT 3620 9829 3610 9852 3612 9899 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

30

1 follow-up statement

572 
WWUS54 KOUN 080046
SVSOUN

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

OKC011-043-073-093-080100-
/O.CON.KOUN.SV.W.0481.000000T0000Z-210908T0100Z/
Kingfisher OK-Blaine OK-Dewey OK-Major OK-
746 PM CDT Tue Sep 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM CDT
FOR NORTHWESTERN KINGFISHER...NORTHERN BLAINE...EASTERN DEWEY AND
SOUTH CENTRAL MAJOR COUNTIES...

At 746 PM CDT, severe thunderstorms were located along a line
extending from 8 miles east of Okeene to 5 miles northeast of Eagle
City to 3 miles south of Taloga, moving south at 20 mph.

HAZARD...Golf ball size hail and 70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect 
         considerable tree damage. Wind damage is also likely to 
         mobile homes, roofs, and outbuildings.

Locations impacted include...
Watonga, Taloga, Okeene, Seiling, Canton, Longdale, Hitchcock,
Oakwood, Putnam, Canton Lake, Eagle City, Homestead, Hucmac and
Southard.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3601 9805 3583 9845 3581 9911 3615 9906
      3616 9901 3614 9896 3616 9894 3617 9852
      3617 9814
TIME...MOT...LOC 0046Z 353DEG 18KT 3610 9816 3598 9850 3600 9895 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

30

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 7:15 PM CDT	Special Weather Statement	OUN	Roger Mills	30 min
Sep 7, 7:43 PM CDT	Special Weather Statement	OUN	Noble	32 min
Sep 7, 7:51 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Blaine, Canadian, Custer, Dewey, Kingfisher	39 min
Sep 7, 8:02 PM CDT	Severe Thunderstorm Warning	OUN	Logan, Noble, Payne	25 min
Sep 7, 8:21 PM CDT	Special Weather Statement	OUN	Custer	24 min
Sep 7, 8:27 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Custer, Dewey	33 min
Sep 7, 8:46 PM CDT	Special Weather Statement	OUN	Custer	29 min
Sep 7, 9:11 PM CDT	Special Weather Statement	OUN	Beckham	34 min
Sep 7, 9:19 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Greer	41 min
Sep 7, 9:23 PM CDT	Special Weather Statement	OUN	Washita	37 min
Sep 7, 9:40 PM CDT	Special Weather Statement	OUN	Kay	35 min
Sep 8, 12:40 AM CDT	Special Weather Statement	OUN	Cotton	35 min
Sep 8, 4:55 AM CDT	Special Weather Statement	OUN	Bryan	35 min
Sep 8, 5:31 AM CDT	Special Weather Statement	OUN	Bryan	29 min
Sep 8, 6:10 AM CDT	Special Weather Statement	OUN	Bryan	35 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2021 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.