Alert archive / Oklahoma / Mesoscale Discussions in 2011

Mesoscale Discussion 925

May 24, 201127 counties in Oklahoma; 13 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 24, 2011, 12:18 PM CDT for 27 counties in Oklahoma; 13 counties in Texas. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued
May 24, 2011, 12:18 PM CDT (17:18 UTC)
Expired
May 24, 2011, 1:45 PM CDT
In force
87 min
Issued by
the Storm Prediction Center
All 40 counties

Blaine County, OK, Caddo County, OK, Canadian County, OK, Carter County, OK, Cleveland County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Garfield County, OK, Garvin County, OK, Grady County, OK, Greer County, OK, Jackson County, OK, Jefferson County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, Major County, OK, McClain County, OK, Noble County, OK, Oklahoma County, OK, Payne County, OK, Pottawatomie County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Archer County, TX, Baylor County, TX, Clay County, TX, Foard County, TX, Hardeman County, TX, Haskell County, TX, Jack County, TX, Knox County, TX, Montague County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Altus AFB radar (KFDR), 51 km from the middle of the area, began a volume at 17:24 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 5.3 hours before the alert went out and 122 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 12:00Z on 2011-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2178 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 12:00Z on 2011-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 422 square meters per square second.19395878Sfc1 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
2178 J/kg
Mixed-layer CIN
-195 J/kg
Mixed-layer LCL
573 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
422 m²/s²
0-3 km storm-relative helicity
490 m²/s²
Significant tornado parameter
0.0
Supercell composite
6.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

987 
ACUS11 KWNS 241718
SWOMCD
SPC MCD 241718 
OKZ000-TXZ000-241845-

MESOSCALE DISCUSSION 0925
NWS STORM PREDICTION CENTER NORMAN OK
1218 PM CDT TUE MAY 24 2011

AREAS AFFECTED...NW TX...WRN AND CNTRL OK

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY 

VALID 241718Z - 241845Z

STORM INITIATION IS EXPECTED ACROSS WRN OK AND NW TX OVER THE NEXT
HOUR. SUPERCELLS SHOULD RAPIDLY DEVELOP WITH A THREAT FOR LARGE HAIL
AND TORNADOES. A TORNADO WATCH WILL LIKELY NEED TO BE ISSUED BY 18Z.


SFC ANALYSIS SHOWS A 997 MB LOW IN THE NRN TX PANHANDLE WITH A
DRYLINE EXTENDING SWD FROM THE LOW ACROSS FAR WRN OK INTO WEST TX.
THE DRYLINE IS STARTING TO ADVANCE EWD WITH VISIBLE SATELLITE
IMAGERY SHOWING AN EXPANDING FIELD OF CUMULUS FROM I-40 IN WRN OK
SWD TO NEAR SAN ANGELO IN WCNTRL TX. AS FURTHER DESTABILIZATION
OCCURS THIS AFTERNOON AND THE CAP WEAKENS...RAPID CELL INITIATION IS
EXPECTED TO OCCUR ALONG THIS CORRIDOR. AS THIS OCCURS...A 50 TO 65
KT MID-LEVEL JET EJECTING NEWD TOWARD THE SRN PLAINS WILL CREATE
STRONG DEEP LAYER SHEAR PROFILES VERY FAVORABLE FOR SUPERCELLS. AS
STORMS INTENSIFY...VERY LARGE HAIL GREATER THAN 2 INCHES IN DIAMETER
WILL BECOME LIKELY. IN ADDITION...A 30 TO 40 KT LOW-LEVEL JET IS IN
PLACE ACROSS NW TX AND WRN OK. AS THIS FEATURE
STRENGTHENS...LOW-LEVEL SHEAR WILL BECOME VERY FAVORABLE FOR
TORNADOES. WITH 0-3 KM STORM RELATIVE HELICITIES INCREASING INTO THE
450 TO 600 M2/S2 RANGE...LONG-TRACK STRONG TORNADOES ARE EXPECTED TO
OCCUR LATE THIS AFTERNOON INTO EARLY THIS EVENING.

..BROYLES.. 05/24/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...TSA...FWD...OUN...SJT...LUB...

LAT...LON   36359864 35549906 34789972 34469989 33560003 32959970
            32809942 32789855 33159793 33799761 34609702 35689660
            36409722 36629823 36359864

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 23, 7:50 PM CDTMesoscale DiscussionSPCComanche, Cotton, Jackson, Jefferson, Stephens, Tillman55 min
May 23, 9:22 PM CDTMesoscale DiscussionSPCAdair, Blaine, Canadian, Cherokee, Creek, Haskell and 15 more23 min
May 23, 9:42 PM CDTSevere Thunderstorm WatchSPCBlaine, Caddo, Canadian, Cleveland, Creek, Grady and 18 more6 hr
May 24, 2:08 AM CDTMesoscale DiscussionSPCCherokee, Creek, Haskell, LeFlore, McIntosh, Muskogee and 5 more97 min
May 24, 12:47 PM CDTTornado Watch PDSSPCAlfalfa, Atoka, Blaine, Bryan, Caddo, Canadian and 51 more11 hr
May 24, 2:35 PM CDTMesoscale DiscussionSPCAlfalfa, Grant, Kay, Woods85 min
May 24, 4:48 PM CDTMesoscale DiscussionSPCCaddo, Canadian, Carter, Cleveland, Cotton, Creek and 21 more87 min
May 24, 6:43 PM CDTMesoscale DiscussionSPCBryan, Carter, Cleveland, Coal, Creek, Garvin and 17 more62 min
May 24, 2:15 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coke, Coleman, Comanche, Concho and 28 more90 min

Nearby

Mesoscale Discussions in Oklahoma, 2011Mesoscale Discussions in Texas, 2011Every mesoscale discussion in 2011

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.