Alert archive / Oklahoma / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 22

March 16, 2021Cowley County, Harper County, Sumner County, Kansas; 25 counties in Oklahoma; 7 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Mar 16, 2021, 7:49 PM CDT for Cowley County, Harper County, Sumner County, Kansas; 25 counties in Oklahoma; 7 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Mar 16, 2021, 7:49 PM CDT (00:49 UTC)
Expired
Mar 17, 2021, 3:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
60 kt
All 35 counties

Cowley County, KS, Harper County, KS, Sumner County, KS, Alfalfa County, OK, Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Garfield County, OK, Grant County, OK, Greer County, OK, Harmon County, OK, Harper County, OK, Jackson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, Major County, OK, Noble County, OK, Payne County, OK, Roger Mills County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Collingsworth County, TX, Donley County, TX, Gray County, TX, Hemphill County, TX, Lipscomb County, TX, Roberts County, TX, Wheeler County, TX

The radar

The Vance AFB radar (KVNX), 132 km from the middle of the area, began a volume at 00:54 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
10%
Ten or more severe wind reports
70%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
80%
One or more hailstones of 2 inches or more
60%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

46 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Mar 16, 8:02 PM CDTSevere Thunderstorm WarningAMACollingsworth33 min
Mar 16, 8:19 PM CDTSevere Thunderstorm WarningOUNBeckham26 min
Mar 16, 8:47 PM CDTSevere Thunderstorm WarningOUNGreer, Harmon, Jackson43 min
Mar 16, 8:49 PM CDTSevere Thunderstorm WarningAMAHemphill, Roberts41 min
Mar 16, 9:12 PM CDTSevere Thunderstorm WarningAMAHemphill, Lipscomb48 min
Mar 16, 9:27 PM CDTSevere Thunderstorm WarningAMALipscomb63 min
Mar 16, 9:29 PM CDTSevere Thunderstorm WarningOUNGreer, Kiowa46 min
Mar 16, 9:32 PM CDTSevere Thunderstorm WarningAMALipscomb58 min
Mar 16, 9:33 PM CDTSevere Thunderstorm WarningOUNEllis42 min
Mar 16, 9:43 PM CDTSevere Thunderstorm WarningAMACarson, Hutchinson, Moore, Ochiltree, Potter, Roberts62 min
Mar 16, 9:55 PM CDTSevere Thunderstorm WarningOUNEllis, Roger Mills35 min
Mar 16, 10:06 PM CDTSevere Thunderstorm WarningOUNBeckham, Greer, Kiowa, Washita39 min
Mar 16, 10:11 PM CDTSevere Thunderstorm WarningOUNEllis, Woodward64 min
Mar 16, 10:12 PM CDTSevere Thunderstorm WarningOUNGreer, Jackson, Kiowa48 min
Mar 16, 10:43 PM CDTSevere Thunderstorm WarningOUNBlaine, Caddo, Custer, Washita47 min
Mar 16, 10:45 PM CDTSevere Thunderstorm WarningOUNDewey, Ellis, Major, Woodward60 min
Mar 16, 10:56 PM CDTSevere Thunderstorm WarningOUNKiowa, Washita49 min
Mar 16, 11:01 PM CDTSevere Thunderstorm WarningAMACarson, Gray, Hemphill, Hutchinson, Ochiltree, Roberts and 1 more59 min
Mar 16, 11:08 PM CDTSevere Thunderstorm WarningAMAHemphill, Lipscomb, Ochiltree, Roberts67 min
Mar 16, 11:17 PM CDTTornado WarningOUNCaddo, Kiowa, Washita43 min
Mar 16, 11:32 PM CDTSevere Thunderstorm WarningOUNAlfalfa, Major, Woods, Woodward58 min
Mar 16, 11:40 PM CDTSevere Thunderstorm WarningOUNCaddo, Washita50 min
Mar 16, 11:47 PM CDTSevere Thunderstorm WarningOUNEllis, Harper, Roger Mills, Woodward58 min
Mar 16, 11:53 PM CDTSevere Thunderstorm WarningOUNGreer, Harmon, Jackson52 min
Mar 16, 11:53 PM CDTSevere Thunderstorm WarningAMAHemphill, Lipscomb, Ochiltree, Roberts52 min
Mar 16, 11:56 PM CDTSevere Thunderstorm WarningOUNCaddo, Washita49 min
Mar 17, 12:09 AM CDTSevere Thunderstorm WarningOUNDewey, Ellis, Roger Mills, Woodward51 min
Mar 17, 12:18 AM CDTSevere Thunderstorm WarningOUNBlaine, Kingfisher42 min
Mar 17, 12:20 AM CDTSevere Thunderstorm WarningOUNBlaine, Caddo, Custer, Washita40 min
Mar 17, 12:32 AM CDTSevere Thunderstorm WarningOUNBeckham, Greer, Kiowa, Washita43 min
Mar 17, 12:34 AM CDTSevere Thunderstorm WarningOUNBlaine, Dewey, Major, Woodward56 min
Mar 17, 12:42 AM CDTSevere Thunderstorm WarningOUNBlaine, Caddo, Canadian31 min
Mar 17, 12:44 AM CDTTornado WarningOUNDewey21 min
Mar 17, 12:54 AM CDTSevere Thunderstorm WarningOUNBlaine, Canadian51 min
Mar 17, 12:59 AM CDTSevere Thunderstorm WarningOUNBlaine, Garfield, Kingfisher, Major46 min
Mar 17, 1:14 AM CDTSevere Thunderstorm WarningOUNGreer, Kiowa, Washita33 min
Mar 17, 1:26 AM CDTSevere Thunderstorm WarningOUNBlaine, Dewey, Kingfisher, Major49 min
Mar 17, 1:27 AM CDTSevere Thunderstorm WarningOUNGarfield, Noble48 min
Mar 17, 1:30 AM CDTSevere Thunderstorm WarningOUNBlaine, Kingfisher45 min
Mar 17, 1:39 AM CDTSevere Thunderstorm WarningOUNBlaine, Kingfisher, Major37 min
Mar 17, 1:42 AM CDTSevere Thunderstorm WarningOUNGarfield16 min
Mar 17, 1:57 AM CDTSevere Thunderstorm WarningOUNBlaine, Custer, Dewey33 min
Mar 17, 2:11 AM CDTSevere Thunderstorm WarningOUNKay, Noble49 min
Mar 17, 2:13 AM CDTSevere Thunderstorm WarningOUNGarfield, Kingfisher, Logan47 min
Mar 17, 2:42 AM CDTFlash Flood WarningOUNBlaine, Kingfisher3 hr
Mar 17, 2:55 AM CDTSevere Thunderstorm WarningOUNGarfield, Grant, Kay, Noble65 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 0.8 hours before the alert went out and 196 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 2021-03-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 626 joules per kilogram.LCLLFCEL10008507005003002001001 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, Norman, OK at 00:00Z on 2021-03-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 square meters per square second.1939587897Sfc1 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
626 J/kg
Mixed-layer CIN
-54 J/kg
Mixed-layer LCL
1825 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
137 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted.

597 
WWUS20 KWNS 170046
SEL2  
SPC WW 170046
KSZ000-OKZ000-TXZ000-170800-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 22
NWS Storm Prediction Center Norman OK
750 PM CDT Tue Mar 16 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  South Central Kansas
  Western and North-Central Oklahoma
  Eastern Texas Panhandle

* Effective this Tuesday night and Wednesday morning from 750 PM
  until 300 AM CDT.

* Primary threats include...
  Widespread large hail and isolated very large hail events to 3
    inches in diameter likely
  Scattered damaging wind gusts to 70 mph likely
  A tornado or two possible

SUMMARY...Thunderstorms are expected to intensify rapidly this
evening along a boundary over northwest Oklahoma and the northeast
Texas Panhandle.  Other isolated cells may develop slightly farther
south.  Storms will track northeastward across the watch, posing a
risk of very large hail, damaging winds, and perhaps a tornado or
two.

The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 90 miles west of
Clinton OK to Ponca City OK. For a complete depiction of the watch
see the associated watch outline update (WOUS64 KWNS WOU2).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.

&&

AVIATION...A few severe thunderstorms with hail surface and aloft to
3 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 450. Mean storm motion vector
24035.

...Hart

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 17, 12:45 AM CDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Butler, Chase, Chautauqua and 21 more90 min
Mar 17, 1:54 AM CDTSevere Thunderstorm WatchSPCAllen, Anderson, Bourbon, Butler, Chautauqua, Cherokee and 10 more6 hr
Mar 17, 4:38 AM CDTMesoscale DiscussionSPCMorton, Stevens6 hr
Mar 17, 5:18 AM CDTMesoscale DiscussionSPCBourbon, Cherokee, Crawford, Labette, Linn, Montgomery and 1 more87 min
Mar 17, 1:18 PM CDTMesoscale DiscussionSPCCherokee57 min
Mar 17, 1:32 AM CDTMesoscale DiscussionSPCLeFlore, McCurtain118 min
Mar 17, 1:56 AM CDTMesoscale DiscussionSPCBlaine, Custer, Garfield, Kay, Kingfisher, Logan and 3 more64 min
Mar 17, 4:04 AM CDTMesoscale DiscussionSPCBryan, Choctaw, McCurtain86 min
Mar 17, 4:37 AM CDTSevere Thunderstorm WatchSPCAtoka, Bryan, Choctaw, McCurtain, Pushmataha5 hr
Mar 17, 6:40 AM CDTMesoscale DiscussionSPCChoctaw, Latimer, LeFlore, McCurtain, Pushmataha95 min
Mar 17, 2:00 PM CDTTornado WatchSPCAdair, Cherokee, Craig, Creek, Delaware, Mayes and 5 more7 hr
Mar 17, 3:37 PM CDTMesoscale DiscussionSPCAdair, Cherokee, Craig, Delaware, Mayes, Nowata and 5 more83 min
Mar 16, 9:27 PM CDTMesoscale DiscussionSPCArcher, Baylor, Brown, Callahan, Coke, Coleman and 30 more93 min
Mar 16, 10:26 PM CDTSevere Thunderstorm WatchSPCBell, Bosque, Brown, Callahan, Coke, Coleman and 44 more7 hr
Mar 17, 2:20 AM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Comanche, Eastland, Erath and 6 more85 min
Mar 17, 8:43 AM CDTTornado WatchSPCAngelina, Nacogdoches, Sabine, San Augustine, Shelby4 hr
Mar 17, 11:35 AM CDTMesoscale DiscussionSPCAngelina, Brazoria, Chambers, Galveston, Hardin, Harris and 10 more85 min
Mar 17, 11:53 AM CDTTornado WatchSPCHardin, Jasper, Jefferson, Newton, Orange, Tyler6 hr

Nearby

Severe Thunderstorm Watches in Oklahoma, 2021Severe Thunderstorm Watches in Texas, 2021Severe Thunderstorm Watches in Kansas, 2021Every severe thunderstorm watch 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.