Alert archive / Oklahoma / Tornado Watches in 2019

Tornado Watch 203

May 20, 201924 counties in Oklahoma; 6 counties in Texas

The Storm Prediction Center issued this tornado watch at May 20, 2019, 10:07 PM CDT for 24 counties in Oklahoma; 6 counties in Texas. It was in force for 9 hr.

The area

The outline as issued.

The facts

Issued
May 20, 2019, 10:07 PM CDT (03:07 UTC)
Expired
May 21, 2019, 7:00 AM CDT
In force
9 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 30 counties

Carter County, OK, Cleveland County, OK, Coal County, OK, Comanche County, OK, Cotton County, OK, Creek County, OK, Garvin County, OK, Grady County, OK, Hughes County, OK, Jefferson County, OK, Johnston County, OK, Lincoln County, OK, Love County, OK, Marshall County, OK, McClain County, OK, Murray County, OK, Okfuskee County, OK, Okmulgee County, OK, Pontotoc County, OK, Pottawatomie County, OK, Seminole County, OK, Stephens County, OK, Tillman County, OK, Tulsa County, OK, Archer County, TX, Baylor County, TX, Clay County, TX, Knox County, TX, Wichita County, TX, Wilbarger County, TX

The radar

The Norman radar (KTLX), 74 km from the middle of the area, began a volume at 03:09 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
50%
One or more EF2 to EF5 tornadoes
30%
Ten or more severe wind reports
60%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 20, 10:07 PM CDTTornado WarningTSAOkmulgee, Tulsa, Wagoner38 min
May 20, 10:22 PM CDTSevere Thunderstorm WarningOUNComanche, Cotton, Tillman38 min
May 20, 10:32 PM CDTSevere Thunderstorm WarningTSAMayes, Rogers, Tulsa, Wagoner43 min
May 20, 10:40 PM CDTSevere Thunderstorm WarningOUNBaylor, Knox, Wilbarger50 min
May 20, 10:45 PM CDTSevere Thunderstorm WarningOUNCaddo, Canadian, Grady45 min
May 20, 10:45 PM CDTTornado WarningOUNKnox17 min
May 20, 10:53 PM CDTSevere Thunderstorm WarningOUNCaddo, Comanche, Cotton, Garvin, Grady, McClain and 1 more52 min
May 20, 11:14 PM CDTFlash Flood Warning EmergencyTSAOsage, Pawnee, Tulsa, Washington6 hr
May 20, 11:26 PM CDTSevere Thunderstorm WarningOUNTillman49 min
May 20, 11:28 PM CDTSevere Thunderstorm WarningOUNBaylor, Knox36 min
May 20, 11:30 PM CDTFlash Flood WarningOUNCleveland, Oklahoma4 hr
May 20, 11:41 PM CDTSevere Thunderstorm WarningOUNCleveland, Grady, McClain, Oklahoma, Pottawatomie37 min
May 20, 11:44 PM CDTFlash Flood Warning EmergencyTSAMayes, Osage, Rogers, Tulsa, Wagoner6 hr
May 20, 11:44 PM CDTFlash Flood WarningOUNKnox4 hr
May 21, 12:18 AM CDTSevere Thunderstorm WarningOUNKnox42 min
May 21, 1:00 AM CDTFlash Flood WarningOUNCanadian, Lincoln, Logan, Oklahoma, Payne4 hr
May 21, 1:03 AM CDTSevere Thunderstorm WarningOUNTillman42 min
May 21, 1:05 AM CDTFlash Flood WarningTSAMuskogee, Okmulgee, Tulsa, Wagoner6 hr
May 21, 1:38 AM CDTSevere Thunderstorm WarningTSACreek, Okmulgee27 min
May 21, 1:43 AM CDTSevere Thunderstorm WarningOUNComanche, Cotton, Jefferson, Stephens, Tillman47 min
May 21, 2:27 AM CDTSevere Thunderstorm WarningOUNGrady, Jefferson, Stephens48 min
May 21, 2:38 AM CDTFlash Flood WarningTSACreek, Tulsa6 hr
May 21, 3:47 AM CDTSevere Thunderstorm WarningOUNCleveland, McClain43 min
May 21, 4:08 AM CDTTornado WarningOUNCleveland14 min
May 21, 4:24 AM CDTSevere Thunderstorm WarningOUNCleveland, Lincoln, Oklahoma, Pottawatomie51 min
May 21, 4:26 AM CDTTornado Warning Tornado observedOUNCleveland, Oklahoma, Pottawatomie34 min
May 21, 4:45 AM CDTSevere Thunderstorm WarningOUNHughes, Lincoln, Pottawatomie, Seminole45 min
May 21, 4:52 AM CDTTornado WarningOUNLincoln23 min
May 21, 4:54 AM CDTFlash Flood WarningOUNLincoln3 hr
May 21, 4:59 AM CDTSevere Thunderstorm WarningTSACreek, Okfuskee46 min
May 21, 5:07 AM CDTFlash Flood WarningTSAOsage, Pawnee, Tulsa, Washington6 hr
May 21, 5:24 AM CDTSevere Thunderstorm WarningTSACreek, Okfuskee, Okmulgee, Tulsa51 min
May 21, 5:27 AM CDTFlash Flood WarningTSAMayes, Osage, Rogers, Tulsa, Wagoner6 hr
May 21, 6:00 AM CDTSevere Thunderstorm WarningTSACreek, Mayes, Muskogee, Okfuskee, Okmulgee, Osage and 4 more60 min
May 21, 6:15 AM CDTTornado WarningOUNAtoka, Bryan, Johnston, Love, Marshall30 min
May 21, 6:17 AM CDTTornado WarningTSARogers, Tulsa43 min
May 21, 6:22 AM CDTTornado WarningOUNHughes53 min
May 21, 6:38 AM CDTTornado WarningOUNAtoka, Bryan, Johnston, Marshall37 min
May 21, 6:43 AM CDTTornado WarningTSAMayes, Nowata, Rogers, Tulsa, Washington47 min
May 21, 6:52 AM CDTTornado WarningOUNCoal, Hughes45 min
May 21, 6:53 AM CDTFlash Flood WarningTSAMuskogee, Okmulgee, Tulsa, Wagoner3 hr
May 21, 6:54 AM CDTTornado WarningOUNAtoka, Coal, Johnston36 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, 3.1 hours before the alert went out and 61 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 2019-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3095 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 2019-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 420 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
3095 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
733 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
420 m²/s²
0-3 km storm-relative helicity
523 m²/s²
Significant tornado parameter
10.8
Supercell composite
43.6

Open this sounding in Storm Lab

The text

As transmitted.

418 
WWUS20 KWNS 210305
SEL3  
SPC WW 210305
OKZ000-TXZ000-211000-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 203
NWS Storm Prediction Center Norman OK
1005 PM CDT Mon May 20 2019

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southern and East-Central Oklahoma
  Western North Texas

* Effective this Monday night and Tuesday morning from 1005 PM
  until 500 AM CDT.

* Primary threats include...
  A few tornadoes and a couple intense tornadoes possible
  Scattered damaging wind gusts to 70 mph likely
  Scattered large hail and isolated very large hail events to 2
    inches in diameter possible

SUMMARY...A mixed mode of storms including a few supercells and
bowing segments will continue to move east-northeastward across the
region into the overnight. A few tornadoes remain a possibility,
with damaging winds and isolated large hail a possibility.

The tornado watch area is approximately along and 60 statute miles
north and south of a line from 50 miles east southeast of Chandler
OK to 50 miles south southwest of Altus OK. For a complete depiction
of the watch see the associated watch outline update (WOUS64 KWNS
WOU3).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and 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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 200...WW 201...WW 202...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 600. Mean
storm motion vector 22030.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 7:38 PM CDTMesoscale DiscussionSPCCanadian, Greer, Harmon, Jackson, Kingfisher, Kiowa and 1 more97 min
May 20, 8:22 PM CDTMesoscale DiscussionSPCAtoka, Beckham, Blaine, Bryan, Caddo, Canadian and 40 more53 min
May 20, 10:30 PM CDTMesoscale DiscussionSPCAdair, Cherokee, Delaware, Haskell, Latimer, LeFlore and 10 more60 min
May 20, 11:06 PM CDTMesoscale DiscussionSPCDelaware24 min
May 21, 12:18 AM CDTTornado WatchSPCAdair, Cherokee, Delaware, Haskell, Latimer, LeFlore and 5 more5 hr
May 21, 2:24 AM CDTMesoscale DiscussionSPCCarter, Cleveland, Coal, Cotton, Garvin, Grady and 11 more96 min
May 21, 4:56 AM CDTMesoscale DiscussionSPCCreek, Hughes, Lincoln, McIntosh, Okfuskee, Okmulgee and 2 more64 min
May 21, 5:09 AM CDTTornado WatchSPCAdair, Cherokee, Craig, Creek, Delaware, Haskell and 14 more9 hr
May 21, 7:26 AM CDTMesoscale DiscussionSPCAdair, Atoka, Bryan, Cherokee, Choctaw, Coal and 21 more94 min
May 20, 8:53 PM CDTMesoscale DiscussionSPCBorden, Dawson, Fisher, Garza, Glasscock, Haskell and 15 more97 min
May 20, 9:52 PM CDTTornado WatchSPCBorden, Brown, Callahan, Coke, Coleman, Concho and 33 more6 hr
May 20, 11:31 PM CDTMesoscale DiscussionSPCBorden, Callahan, Coke, Coleman, Crane, Crockett and 25 more59 min
May 20, 11:41 PM CDTMesoscale DiscussionSPCBorden, Callahan, Coke, Coleman, Crane, Crockett and 25 more64 min

Nearby

Tornado Watches in Oklahoma, 2019Tornado Watches in Texas, 2019Every tornado watch in 2019

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.