Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 514

April 13, 201230 counties in Oklahoma; Childress County, Collingsworth County, Hardeman County, Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2012, 7:35 PM CDT for 30 counties in Oklahoma; Childress County, Collingsworth County, Hardeman County, Texas. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued
Apr 13, 2012, 7:35 PM CDT (00:35 UTC)
Expired
Apr 13, 2012, 8:30 PM CDT
In force
55 min
Issued by
the Storm Prediction Center
All 33 counties

Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Cleveland County, OK, Comanche County, OK, Creek County, OK, Custer County, OK, Dewey County, OK, Garfield County, OK, Grady County, OK, Grant County, OK, Greer County, OK, Harmon County, OK, Jackson 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, Osage County, OK, Pawnee County, OK, Payne County, OK, Rogers County, OK, Tillman County, OK, Tulsa County, OK, Washita County, OK, Childress County, TX, Collingsworth County, TX, Hardeman County, TX

The radar

The Altus AFB radar (KFDR), 94 km from the middle of the area, began a volume at 00:35 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.

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 00:00Z, 0.6 hours before the alert went out and 112 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 2012-04-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2227 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 2012-04-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 269 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
2227 J/kg
Mixed-layer CIN
-11 J/kg
Mixed-layer LCL
617 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
269 m²/s²
0-3 km storm-relative helicity
389 m²/s²
Significant tornado parameter
3.5
Supercell composite
15.6

Open this sounding in Storm Lab

The text

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

399 
ACUS11 KWNS 140035
SWOMCD
SPC MCD 140035 
OKZ000-TXZ000-140130-

MESOSCALE DISCUSSION 0514
NWS STORM PREDICTION CENTER NORMAN OK
0735 PM CDT FRI APR 13 2012

AREAS AFFECTED...SOUTHWEST/CENTRAL/NORTHEAST OK AND PART OF
NORTHWEST TX

CONCERNING...TORNADO WATCH 160...

VALID 140035Z - 140130Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 160 CONTINUES.

TORNADO WATCH 160 CONTINUES UNTIL 02Z...WITH POTENTIAL FOR TORNADOES
AND LARGE HAIL. INDICATIONS ARE THAT A REPLACEMENT TORNADO WATCH
WILL BE NEEDED IN THE NEXT HOUR OR SO FOR PORTIONS OF OK AND PERHAPS
ADJACENT PARTS OF NORTHWEST TX/EASTERN TX PANHANDLE.

MOST CONCENTRATED/SUSTAINED SEVERE POTENTIAL IS EXPECTED TO REMAIN
ESPECIALLY FOCUSED ACROSS SOUTHWEST OK/ADJACENT NORTHWEST TX OVER
THE NEXT FEW HOURS. AN ONGOING SUPERCELL IN KIOWA COUNTY OK HAD
TEMPORARILY WEAKENED FROM ITS EARLIER PROLIFIC INTENSITY AS OF
0000Z...BUT A REINTENSIFICATION HAS OCCURRED WITHIN A RELATIVELY
FAVORABLE ENVIRONMENT ACROSS SOUTHWEST OK. THE AFOREMENTIONED STORM
HAS APPEARED TO FAVOR THE IMMEDIATE COOL SIDE OF AN OUTFLOW BOUNDARY
LEFT BY EARLIER STORMS. A MORE STABLE RAIN-COOLED AIRMASS CURRENTLY
EXISTS ACROSS CENTRAL OK...ALTHOUGH THE 00Z OBSERVED SOUNDING FROM
NORMAN WAS INDICATIVE OF ONLY A VERY SHALLOW STABLE LAYER /0.5 KM/.
AS SUCH...COLD POOL ABATEMENT/OUTFLOW MODIFICATION COULD YET OCCUR
THIS EVENING INTO CENTRAL OK AS A LOW LEVEL JET INTENSIFIES.

WEST OF THE LEAD STORM ACROSS KIOWA COUNTY...ADDITIONAL SUSTAINED
SUPERCELL DEVELOPMENT CAN BE EXPECTED JUST NORTH OF THE CHILDRESS TX
AREA INTO FAR SOUTHWEST/EVENTUALLY WEST-CENTRAL OK...WITH THESE
STORMS ALSO LIKELY TO FAVOR THE PERPETUALLY-REINFORCED WEST-EAST
OUTFLOW BOUNDARY AS A MODERATELY UNSTABLE /2000-2500 J PER KG
MLCAPE/ BOUNDARY LAYER REMAINS ALONG/SOUTH OF IT. REGIONAL WIND
PROFILERS/WSR-88D DERIVED WINDS ARE INDICATIVE OF A
STRENGTHENING/BACKING TREND WITHIN THE LOWEST FEW KM DURING THE PAST
SEVERAL HOURS...WITH THE FREDERICK OK WSR-88D VWP ALREADY INDICATIVE
OF 200+ M2/S2 0-1 KM SRH. THIS SAME TREND IS EXPECTED TO CONTINUE
THIS EVENING AND HELP MAINTAIN A SUPERCELL/TORNADO THREAT
TONIGHT...ESPECIALLY ACROSS MUCH OF SOUTHWEST OK/ADJACENT PARTS OF
TX.

..GUYER.. 04/14/2012

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

ATTN...WFO...TSA...OUN...LUB...AMA...

LAT...LON   34209999 34580050 35370004 36829775 36499535 35489648
            34179897 34209999

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 13, 8:36 PM CDTTornado WatchSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 31 more7 hr
Apr 13, 9:58 PM CDTMesoscale DiscussionSPCBeckham, Blaine, Caddo, Canadian, Cleveland, Comanche and 19 more92 min
Apr 13, 11:45 PM CDTMesoscale DiscussionSPCBeckham, Blaine, Caddo, Canadian, Cleveland, Comanche and 20 more90 min
Apr 14, 2:40 AM CDTMesoscale DiscussionSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 31 more65 min
Apr 14, 3:42 AM CDTTornado WatchSPCCraig, Creek, Delaware, Kay, Lincoln, Logan and 11 more5 hr
Apr 14, 7:11 AM CDTMesoscale DiscussionSPCCraig, Delaware, Kay, Logan, Mayes, Noble and 8 more64 min
Apr 14, 9:42 AM CDTMesoscale DiscussionSPCBeaver, Beckham, Ellis, Harper, Roger Mills, Texas93 min
Apr 14, 10:43 AM CDTTornado Watch PDSSPCAlfalfa, Beckham, Blaine, Custer, Dewey, Ellis and 12 more7 hr
Apr 14, 11:44 AM CDTMesoscale DiscussionSPCAlfalfa, Beaver, Ellis, Garfield, Grant, Harper and 3 more61 min
Apr 14, 12:11 PM CDTMesoscale DiscussionSPCGrant, Kay, Noble, Osage, Pawnee, Washington64 min
Apr 14, 1:23 PM CDTMesoscale DiscussionSPCBeaver, Beckham, Blaine, Caddo, Canadian, Carter and 21 more2 hr
Apr 14, 3:01 PM CDTMesoscale DiscussionSPCAlfalfa, Beckham, Custer, Dewey, Ellis, Greer and 9 more29 min
Apr 14, 3:48 PM CDTMesoscale DiscussionSPCAlfalfa, Beckham, Blaine, Custer, Dewey, Ellis and 10 more57 min
Apr 14, 4:54 PM CDTMesoscale DiscussionSPCAlfalfa, Dewey, Ellis, Grant, Harper, Major and 3 more66 min
Apr 14, 5:24 PM CDTTornado Watch PDSSPCAlfalfa, Beaver, Beckham, Blaine, Custer, Dewey and 18 more9 hr
Apr 13, 9:23 PM CDTMesoscale DiscussionSPCBriscoe, Childress, Collingsworth, Cottle, Donley, Hall and 1 more97 min

Nearby

Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Texas, 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.