Alert archive / Oklahoma / Mesoscale Discussions in 2003

Mesoscale Discussion 472

April 15, 200322 counties in Oklahoma; 6 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 15, 2003, 8:35 PM CDT for 22 counties in Oklahoma; 6 counties in Texas. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued: Apr 15, 2003, 8:35 PM CDT (01:35 UTC)
Expired: Apr 15, 2003, 10:30 PM CDT
In force: 115 min
Issued by: the Storm Prediction Center

All 28 counties

Carter County, OK, Cleveland County, OK, Creek County, OK, Garvin County, OK, Grady County, OK, Jefferson County, OK, Johnston County, OK, Lincoln County, OK, Logan County, OK, Love County, OK, Marshall County, OK, McClain County, OK, Murray County, OK, Noble County, OK, Okfuskee County, OK, Oklahoma County, OK, Pawnee County, OK, Payne County, OK, Pontotoc County, OK, Pottawatomie County, OK, Seminole County, OK, Stephens County, OK, Clay County, TX, Cooke County, TX, Grayson County, TX, Jack County, TX, Montague County, TX, Wise County, TX

The radar

The Norman radar (KTLX), 65 km from the middle of the area, began a volume at 01:37 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, 1.6 hours before the alert went out and 49 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 15 J/kg
Mixed-layer CIN: -337 J/kg
Mixed-layer LCL: 1137 m above ground
0-6 km bulk shear: 65 kt
0-1 km storm-relative helicity: 380 m²/s²
0-3 km storm-relative helicity: 627 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

023 
ACUS11 KWNS 160136
SWOMCD
SPC MCD 160135 
OKZ000-TXZ000-160330-

MESOSCALE DISCUSSION 0472
NWS STORM PREDICTION CENTER NORMAN OK
0835 PM CDT TUE APR 15 2003

AREAS AFFECTED...OK...NORTH CENTRAL TX

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 160135Z - 160330Z

...SEVERE THUNDERSTORMS WILL SOON MOVE INTO PORTIONS OF
CENTRAL/SRN OK...AND PARTS OF NORTH CENTRAL TX.  WW WILL BE
ISSUED SHORTLY...

WELL DEFINED UPPER SHORTWAVE TROUGH IS EJECTING NEWD ACROSS NM
INTO THE SRN PLAINS THIS EVENING.  AHEAD OF THIS FEATURE...VERY
STRONG LOW LEVEL SHEAR AND FOCUSED PRESSURE FALLS FAVOR CONTINUED
EWD MOVEMENT OF ONGOING SEVERE THUNDERSTORM ACTIVITY.  ALTHOUGH
DIAGNOSED INSTABILITY IS SOMEWHAT MARGINAL...ORGANIZATION OF
CONVECTION AND STRENGTH OF SHEAR SUGGEST SEVERE THREAT WILL
INCREASE ACROSS MUCH OF CENTRAL OK...SWD INTO NORTH TX OVER THE
NEXT FEW HOURS.  WW WILL BE ISSUED SOON.

..DARROW.. 04/16/2003

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

ATTN...WFO...TSA...FWD...OUN...

33999825 35989779 36789738 36529594 33459670 32799832

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 15, 7:11 PM CDT	Mesoscale Discussion	SPC	Comanche, Harmon, Jackson, Tillman	2 hr
Apr 15, 9:00 PM CDT	Tornado Watch	SPC	Carter, Cleveland, Coal, Creek, Garvin, Grady and 15 more	5 hr
Apr 15, 9:04 PM CDT	Mesoscale Discussion	SPC	Alfalfa, Blaine, Caddo, Canadian, Comanche, Cotton and 10 more	86 min
Apr 15, 11:00 PM CDT	Mesoscale Discussion	SPC	Canadian, Carter, Cleveland, Coal, Cotton, Creek and 21 more	2 hr
Apr 15, 11:20 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Cherokee, Craig, Creek, Delaware, Haskell and 17 more	6 hr
Apr 16, 2:01 AM CDT	Mesoscale Discussion	SPC	Adair, Cherokee, Craig, Delaware, Haskell, Latimer and 12 more	119 min
Apr 16, 1:41 AM CDT	Mesoscale Discussion	SPC	Brown, Comanche, Coryell, Erath, Hamilton, Kimble and 8 more	2 hr

Nearby

Mesoscale Discussions in Oklahoma, 2003 Mesoscale Discussions in Texas, 2003 Every mesoscale discussion in 2003

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.