Alert archive / Oklahoma / Mesoscale Discussions in 2012

Mesoscale Discussion 423

April 2, 201219 counties in Oklahoma; 18 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 2, 2012, 9:12 PM CDT for 19 counties in Oklahoma; 18 counties in Texas. It was in force for 63 min.

The area

The outline as issued.

The facts

Issued
Apr 2, 2012, 9:12 PM CDT (02:12 UTC)
Expired
Apr 2, 2012, 10:15 PM CDT
In force
63 min
Issued by
the Storm Prediction Center
All 37 counties

Beaver County, OK, Beckham County, OK, Caddo County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Greer County, OK, Harmon County, OK, Harper County, OK, Jackson County, OK, Jefferson County, OK, Kiowa County, OK, Roger Mills County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Woodward County, OK, Archer County, TX, Baylor County, TX, Clay County, TX, Hardeman County, TX, Haskell County, TX, Hemphill County, TX, Jack County, TX, Knox County, TX, Lipscomb County, TX, Ochiltree County, TX, Palo Pinto County, TX, Shackelford County, TX, Stephens County, TX, Throckmorton County, TX, Wheeler County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Altus AFB radar (KFDR), 64 km from the middle of the area, began a volume at 02:16 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, 2.2 hours before the alert went out and 199 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 2012-04-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1334 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 2012-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 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
1334 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
1408 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
61 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

392 
ACUS11 KWNS 030212
SWOMCD
SPC MCD 030212 
TXZ000-OKZ000-KSZ000-030315-

MESOSCALE DISCUSSION 0423
NWS STORM PREDICTION CENTER NORMAN OK
0912 PM CDT MON APR 02 2012

AREAS AFFECTED...NERN TX PANHANDLE...WRN OK...TX BIG COUNTRY

CONCERNING...SEVERE THUNDERSTORM WATCH 129...

VALID 030212Z - 030315Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 129
CONTINUES.

REPLACEMENT OF PORTIONS OF WW 129 WILL LIKELY BE COORDINATED BY
03Z...PRIOR TO 04Z SCHEDULED EXPIRATION.

02Z SURFACE ANALYSIS PLACED A NEARLY STATIONARY CYCLONE OVER THE
NERN TX PANHANDLE WITH A PACIFIC COLD FRONT/DRYLINE ARCING SWD
TOWARDS THE TX BIG COUNTRY. TSTMS RAPIDLY GREW UPSCALE INTO A QLCS
AS THE COLD FRONT OVERTOOK THE DRYLINE ACROSS THE NERN TX PANHANDLE
INTO NWRN TX. LOW-LEVEL SELYS HAVE STRENGTHENED AHEAD OF THIS LINE
TO 30-40 KT PER FDR VWP DATA MAINTAINING A FEED OF LOWER TO MIDDLE
60S SURFACE DEW POINTS ACROSS WRN OK. FARTHER E...SURFACE DEW POINTS
HAVE FALLEN INTO MIDDLE 50S ACROSS S-CNTRL OK IN THE WAKE OF
CONVECTIVE OUTFLOW FROM THE DYING MCS OVER THE LOWER MS VALLEY. AS
SUCH...GREATEST SEVERE THREAT SHOULD EXIST DURING THE NEXT FEW HOURS
ACROSS MAINLY SWRN OK/NWRN TX. CONVECTIVE MODE WILL LARGELY MITIGATE
SIGNIFICANT HAIL...BUT THREATS FOR EMBEDDED SEVERE HAIL ALONG WITH
ISOLATED DAMAGING WINDS AND EVEN A BRIEF TORNADO WILL REMAIN
POSSIBLE.

..GRAMS.. 04/03/2012

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

ATTN...WFO...FWD...OUN...DDC...SJT...AMA...

LAT...LON   35690070 36120089 36530091 36890071 37150022 37159981
            35519821 34919785 33519771 32929797 32739821 32609860
            32639916 32939973 33219985 34199976 35060003 35690070

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 2, 7:17 PM CDTMesoscale DiscussionSPCBeaver, Ellis, Harper, Roger Mills, Texas58 min
Apr 2, 10:51 PM CDTSevere Thunderstorm WatchSPCAlfalfa, Blaine, Caddo, Canadian, Comanche, Cotton and 14 more5 hr
Apr 3, 1:14 AM CDTMesoscale DiscussionSPCCarter, Cleveland, Comanche, Cotton, Garfield, Garvin and 12 more2 hr
Apr 3, 3:32 AM CDTMesoscale DiscussionSPCCaddo, Canadian, Comanche, Cotton, Grady, Jefferson and 2 more88 min
Apr 3, 8:36 AM CDTMesoscale DiscussionSPCBryan, Carter, Jefferson, Johnston, Love, Marshall and 2 more84 min
Apr 3, 9:18 AM CDTSevere Thunderstorm WatchSPCAtoka, Bryan, Carter, Choctaw, Coal, Jefferson and 5 more8 hr
Apr 3, 11:47 AM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Jefferson, Johnston and 3 more118 min
Apr 3, 2:21 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Johnston, Love and 2 more84 min
Apr 3, 2:36 PM CDTTornado WatchSPCMcCurtain7 hr
Apr 3, 3:05 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Coal, Johnston and 5 more85 min
Apr 3, 3:43 PM CDTSevere Thunderstorm WatchSPCAtoka, Bryan, Choctaw, Haskell, Latimer, LeFlore and 3 more6 hr
Apr 2, 11:45 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Comanche, Concho, Eastland and 17 more2 hr
Apr 3, 12:08 PM CDTTornado WatchSPCAnderson, Bell, Bosque, Collin, Coryell, Dallas and 30 more9 hr
Apr 3, 1:12 PM CDTMesoscale DiscussionSPCBosque, Collin, Dallas, Denton, Ellis, Erath and 16 more93 min
Apr 3, 1:46 PM CDTMesoscale DiscussionSPCCamp, Cass, Cherokee, Franklin, Gregg, Harrison and 9 more89 min
Apr 3, 4:38 PM CDTMesoscale DiscussionSPCAustin, Bastrop, Brazos, Burleson, Caldwell, Fayette and 10 more67 min
Apr 3, 5:00 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Delta, Falls and 18 more60 min
Apr 3, 6:53 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Bastrop, Bowie, Brazos, Burleson and 24 more67 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.