Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 971

May 29, 20125 counties in Kansas; 38 counties in Oklahoma

The Storm Prediction Center issued this mesoscale discussion at May 29, 2012, 8:21 PM CDT for 5 counties in Kansas; 38 counties in Oklahoma. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued
May 29, 2012, 8:21 PM CDT (01:21 UTC)
Expired
May 29, 2012, 9:15 PM CDT
In force
54 min
Issued by
the Storm Prediction Center
All 43 counties

Barber County, KS, Clark County, KS, Comanche County, KS, Harper County, KS, Sumner County, KS, Alfalfa County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Carter County, OK, Cleveland County, OK, Coal County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Garfield County, OK, Garvin County, OK, Grady County, OK, Grant County, OK, Harper County, OK, Jefferson County, OK, Johnston County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, Major County, OK, McClain County, OK, Murray County, OK, Noble County, OK, Oklahoma County, OK, Payne County, OK, Pontotoc County, OK, Pottawatomie County, OK, Seminole County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Woods County, OK, Woodward County, OK

The radar

The Norman radar (KTLX), 99 km from the middle of the area, began a volume at 01:22 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 nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 1.4 hours before the alert went out and 92 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 2012-05-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2199 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 2012-05-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -23 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
2199 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
1607 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
192 m²/s²
Significant tornado parameter
0.5
Supercell composite
6.2

Open this sounding in Storm Lab

The text

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

996 
ACUS11 KWNS 300121
SWOMCD
SPC MCD 300121 
OKZ000-KSZ000-TXZ000-300215-

MESOSCALE DISCUSSION 0971
NWS STORM PREDICTION CENTER NORMAN OK
0821 PM CDT TUE MAY 29 2012

AREAS AFFECTED...CNTRL OK...FAR NW TX

CONCERNING...SEVERE THUNDERSTORM WATCH 317...

VALID 300121Z - 300215Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 317
CONTINUES.

SUMMARY...SEVERE THREAT CONTINUES ACROSS WW 317 WITH THE THREAT FOR
VERY LARGE AND DAMAGING HAIL DURING THE NEXT SEVERAL HOURS.

DISCUSSION...SEWD/SWD MOVING LINE OF SUPERCELL THUNDERSTORMS ACROSS
CNTRL OK WILL CONTINUE TO PRODUCE VERY LARGE AND DAMAGING HAIL AS
WELL AS STRONG WIND GUSTS. 00Z OUN SOUNDING DEPICTED NEAR 2500 J/KG
OF MLCAPE WITH 500-700 MB LAPSE RATE OF 7.7 C/KM.
ADDITIONALLY...SFC-3 KM LAPSE RATE WAS 8.1 C/KM. VERY MODEST WARM
LAYER BETWEEN 820-720 MB RESULTED IN SOME MLCINH.
HOWEVER...SUPERCELL STORMS SHOULD CONTINUE TO MOVE SEWD TOWARDS THE
OKC METRO AREA. A LEFT-MOVING SUPERCELL CURRENTLY MOVING ACROSS
CLEVELAND AND OKLAHOMA COUNTIES WILL LIKELY INTERACT WITH THE LINE
OF SEWD MOVING SUPERCELLS. BRIEFLY ENHANCED LOW-LEVEL VORTICITY
ASSOCIATED WITH OUTFLOW BOUNDARY INTERSECT MAY RESULT IN AN ENHANCED
TORNADO THREAT ACROSS CANADIAN AND OKLAHOMA COUNTIES.  

ADDITIONAL SUPERCELL ACROSS FAR NW TX IS ALSO EXPECTED TO PERSIST
WITH THE THREAT FOR VERY LARGE AND DAMAGING HAIL AS WELL AS STRONG
WIND GUSTS.

..MOSIER.. 05/30/2012

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

ATTN...WFO...TSA...ICT...OUN...DDC...AMA...

LAT...LON   34109899 37530044 37549735 34119603 34109899

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 30, 1:05 PM CDTMesoscale DiscussionSPCBarton, Edwards, Ellis, Ellsworth, Finney, Ford and 19 more85 min
May 30, 3:57 PM CDTSevere Thunderstorm WatchSPCAnderson, Barber, Barton, Butler, Chase, Chautauqua and 80 more7 hr
May 30, 6:57 PM CDTMesoscale DiscussionSPCAnderson, Barber, Barton, Butler, Chase, Chautauqua and 76 more2 hr
May 29, 7:33 PM CDTSevere Thunderstorm WatchSPCChoctaw, Creek, Haskell, Latimer, LeFlore, McIntosh and 11 more5 hr
May 29, 9:10 PM CDTMesoscale DiscussionSPCAtoka, Canadian, Carter, Cleveland, Coal, Garvin and 10 more95 min
May 29, 11:28 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Cleveland, Coal and 17 more62 min
May 30, 12:43 AM CDTSevere Thunderstorm WatchSPCMcCurtain7 hr
May 30, 2:43 AM CDTMesoscale DiscussionSPCCotton, Tillman92 min
May 30, 3:38 PM CDTTornado WatchSPCBeaver, Harmon5 hr
May 30, 5:47 PM CDTMesoscale DiscussionSPCBeckham, Blaine, Comanche, Custer, Dewey, Ellis and 10 more88 min
May 30, 6:13 PM CDTSevere Thunderstorm WatchSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Carter and 37 more8 hr

Nearby

Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Kansas, 2012Every mesoscale discussion in 2012

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.