Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 63, NWS Norman, OK

April 9, 2021Caddo County, Canadian County, Grady County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Apr 9, 2021, 4:36 PM CDT for Caddo County, Canadian County, Grady County, Oklahoma. It was in force for 39 min. 3 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: Apr 9, 2021, 4:36 PM CDT (21:36 UTC)
Expired: Apr 9, 2021, 5:15 PM CDT
In force: 39 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Caddo County, OK, Canadian County, OK, Grady County, OK

The radar

The Norman radar (KTLX), 73 km from the middle of the area, began a volume at 21:35 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
Apr 9, 4:53 PM CDT	HAIL 2	6 Sw Minco, OK
Apr 9, 4:56 PM CDT	HAIL 2.75	6 Sw Minco, OK
Apr 9, 5:19 PM CDT	HAIL 2	1 W Pocasset, OK	NORTH SIDE WINDOWS BROKEN ON HOMES

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 9, 3:55 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 9.6 hours before the alert went out and 62 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: 1068 J/kg
Mixed-layer CIN: -311 J/kg
Mixed-layer LCL: 1414 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 137 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.6

Open this sounding in Storm Lab

The text

As transmitted.

941 
WUUS54 KOUN 092136
SVROUN
OKC015-017-051-092215-
/O.NEW.KOUN.SV.W.0063.210409T2136Z-210409T2215Z/

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

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  Northwestern Grady County in central Oklahoma...
  East central Caddo County in southwestern Oklahoma...
  Southwestern Canadian County in central Oklahoma...

* Until 515 PM CDT.

* At 436 PM CDT, a severe thunderstorm was located 4 miles northwest
  of Cogar, moving southeast at 20 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...
  Union City, Minco, Pocasset, Cogar and Cedar Lake. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3534 9829 3545 9818 3538 9781 3519 9790
      3513 9799
TIME...MOT...LOC 2136Z 304DEG 18KT 3537 9819 

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

Mahale

4 follow-up statements

557 
WWUS54 KOUN 092142
SVSOUN

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

OKC015-017-051-092215-
/O.CON.KOUN.SV.W.0063.000000T0000Z-210409T2215Z/
Grady OK-Caddo OK-Canadian OK-
442 PM CDT Fri Apr 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM CDT
FOR NORTHWESTERN GRADY...EAST CENTRAL CADDO AND SOUTHWESTERN CANADIAN
COUNTIES...

At 441 PM CDT, a severe thunderstorm was located near Cogar, moving
southeast at 20 mph.

HAZARD...Golf 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...
Union City, Minco, Pocasset, Cogar and Cedar Lake. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

&&

LAT...LON 3534 9829 3545 9818 3538 9781 3519 9790
      3513 9799
TIME...MOT...LOC 2141Z 304DEG 18KT 3535 9816 

HAIL...1.75IN
WIND...60MPH
 
$$

Mahale

368 
WWUS54 KOUN 092148
SVSOUN

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

OKC015-017-051-092215-
/O.CON.KOUN.SV.W.0063.000000T0000Z-210409T2215Z/
Grady OK-Caddo OK-Canadian OK-
448 PM CDT Fri Apr 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM CDT
FOR NORTHWESTERN GRADY...NORTHEASTERN CADDO AND SOUTH CENTRAL
CANADIAN COUNTIES...

At 448 PM CDT, a severe thunderstorm was located over Cogar, moving
southeast at 20 mph.

HAZARD...Two inch 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...
Union City, Minco, Pocasset and Cogar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

&&

LAT...LON 3529 9822 3544 9812 3538 9781 3519 9790
      3513 9799
TIME...MOT...LOC 2148Z 304DEG 18KT 3533 9812 

HAIL...2.00IN
WIND...60MPH
 
$$

Mahale

392 
WWUS54 KOUN 092157
SVSOUN

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

OKC015-017-051-092215-
/O.CON.KOUN.SV.W.0063.000000T0000Z-210409T2215Z/
Grady OK-Caddo OK-Canadian OK-
457 PM CDT Fri Apr 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM CDT
FOR NORTHWESTERN GRADY...NORTHEASTERN CADDO AND SOUTH CENTRAL
CANADIAN COUNTIES...

At 457 PM CDT, a severe thunderstorm was located near Cogar, moving
southeast at 20 mph.

This is a very dangerous storm.

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

SOURCE...Trained weather spotters southwest of Minco.

IMPACT...People and animals outdoors will be severely injured. 
         Expect shattered windows, extensive damage to roofs, 
         siding, and vehicles.

Locations impacted include...
Minco, Pocasset and Cogar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

&&

LAT...LON 3529 9822 3540 9810 3534 9783 3519 9790
      3513 9799
TIME...MOT...LOC 2157Z 304DEG 18KT 3530 9807 

HAIL...2.75IN
WIND...60MPH
 
$$

Mahale

395 
WWUS54 KOUN 092159
SVSOUN

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

OKC015-017-051-092215-
/O.CON.KOUN.SV.W.0063.000000T0000Z-210409T2215Z/
Grady OK-Caddo OK-Canadian OK-
459 PM CDT Fri Apr 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM CDT
FOR NORTHWESTERN GRADY...NORTHEASTERN CADDO AND SOUTH CENTRAL
CANADIAN COUNTIES...

At 458 PM CDT, a severe thunderstorm was located 4 miles southeast of
Cogar, moving southeast at 20 mph.

This is a very dangerous storm.

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

SOURCE...Trained weather spotters reported baseball size hail 
         southwest of Minco. 

IMPACT...People and animals outdoors will be severely injured. 
         Expect shattered windows, extensive damage to roofs, 
         siding, and vehicles.

Locations impacted include...
Minco, Pocasset and Cogar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

&&

LAT...LON 3529 9822 3540 9810 3534 9783 3519 9790
      3513 9799
TIME...MOT...LOC 2158Z 304DEG 18KT 3530 9806 

HAIL...2.75IN
WIND...60MPH
 
$$

Mahale

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 9, 2:57 AM CDT	Wind Advisory	OUN	Alfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 31 more	20 hr
Apr 9, 10:21 AM CDT	Special Weather Statement	OUN	Bryan	24 min
Apr 9, 10:32 AM CDT	Special Weather Statement	OUN	Bryan	28 min
Apr 9, 3:21 PM CDT	Special Weather Statement	OUN	Greer	24 min
Apr 9, 3:28 PM CDT	Severe Thunderstorm Warning	OUN	Greer	23 min
Apr 9, 3:35 PM CDT	Special Weather Statement	OUN	Washita	40 min
Apr 9, 3:39 PM CDT	Special Weather Statement	OUN	Kingfisher	36 min
Apr 9, 3:49 PM CDT	Special Weather Statement	OUN	Canadian	26 min
Apr 9, 3:52 PM CDT	Special Weather Statement	OUN	Greer	23 min
Apr 9, 3:57 PM CDT	Severe Thunderstorm Warning	OUN	Caddo, Canadian, Grady	48 min
Apr 9, 4:12 PM CDT	Special Weather Statement	OUN	Logan	33 min
Apr 9, 4:13 PM CDT	Special Weather Statement	OUN	Washita	32 min
Apr 9, 4:23 PM CDT	Special Weather Statement	OUN	Grant	37 min
Apr 9, 4:25 PM CDT	Severe Thunderstorm Warning	OUN	Logan, Payne	50 min
Apr 9, 4:29 PM CDT	Severe Thunderstorm Warning	OUN	Kiowa, Washita	16 min
Apr 9, 4:52 PM CDT	Special Weather Statement	OUN	Kingfisher	23 min
Apr 9, 4:53 PM CDT	Severe Thunderstorm Warning	OUN	Kingfisher	52 min
Apr 9, 5:06 PM CDT	Severe Thunderstorm Warning	OUN	Grady	39 min
Apr 9, 5:17 PM CDT	Severe Thunderstorm Warning	OUN	Logan, Noble, Payne	43 min
Apr 9, 5:18 PM CDT	Severe Thunderstorm Warning	OUN	Kingfisher, Logan, Oklahoma	42 min
Apr 9, 5:25 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Logan, Payne	50 min
Apr 9, 5:31 PM CDT	Severe Thunderstorm Warning	OUN	Grady, McClain	44 min
Apr 9, 5:36 PM CDT	Special Weather Statement	OUN	Pottawatomie	24 min
Apr 9, 5:39 PM CDT	Special Weather Statement	OUN	Lincoln	36 min
Apr 9, 5:48 PM CDT	Special Weather Statement	OUN	Lincoln	27 min
Apr 9, 5:51 PM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	39 min
Apr 9, 5:57 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln, Logan, Oklahoma	48 min
Apr 9, 6:05 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, Grady, McClain, Stephens	40 min
Apr 9, 6:09 PM CDT	Special Weather Statement	OUN	Lincoln	36 min
Apr 9, 6:22 PM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie, Seminole	27 min
Apr 9, 6:34 PM CDT	Severe Thunderstorm Warning	OUN	Lincoln	56 min
Apr 9, 6:38 PM CDT	Special Weather Statement	OUN	Pottawatomie	52 min
Apr 9, 6:58 PM CDT	Special Weather Statement	OUN	Pottawatomie, Seminole	47 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.