Alert archive / Texas / Mesoscale Discussions in 2003

Mesoscale Discussion 1069

May 19, 200316 counties in Oklahoma; 18 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 19, 2003, 6:58 PM CDT for 16 counties in Oklahoma; 18 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 19, 2003, 6:58 PM CDT (23:58 UTC)
Expired
May 19, 2003, 9:00 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 34 counties

Carter County, OK, Cleveland County, OK, Cotton County, OK, Garvin County, OK, Grady County, OK, Hughes County, OK, Jefferson County, OK, Lincoln County, OK, Love County, OK, McClain County, OK, Murray County, OK, Oklahoma County, OK, Pontotoc County, OK, Pottawatomie County, OK, Seminole County, OK, Stephens County, OK, Archer County, TX, Brown County, TX, Callahan County, TX, Clay County, TX, Coleman County, TX, Comanche County, TX, Eastland County, TX, Jack County, TX, Montague County, TX, Palo Pinto County, TX, Runnels County, TX, Shackelford County, TX, Stephens County, TX, Taylor County, TX, Throckmorton County, TX, Wichita County, TX, Wise County, TX, Young County, TX

The radar

The Altus AFB radar (KFDR), 100 km from the middle of the area, began a volume at 00:03 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

Fort Sill, OK (KFSI), launched 12:00Z, 12.0 hours before the alert went out and 125 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, Fort Sill, OK at 12:00Z on 2003-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 196 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Sill, OK at 12:00Z on 2003-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 330 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
196 J/kg
Mixed-layer CIN
-776 J/kg
Mixed-layer LCL
1418 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
330 m²/s²
0-3 km storm-relative helicity
360 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.

888 
ACUS11 KWNS 192359
SWOMCD
SPC MCD 192358 
OKZ000-TXZ000-200200-

MESOSCALE DISCUSSION 1069
NWS STORM PREDICTION CENTER NORMAN OK
0658 PM CDT MON MAY 19 2003

AREAS AFFECTED...CNTRL/SRN OK...NWRN TX

CONCERNING...SEVERE THUNDERSTORM WATCH 415...

VALID 192358Z - 200200Z

ISOLATED SUPERCELLS HAVE DEVELOPED ACROSS NRN PORTIONS OF THE WW
ALONG WIND SHIFT...ESPECIALLY OVER STEPHENS COUNTY.  DESPITE VERY
MOIST BOUNDARY LAYER AND SUPERCELL STRUCTURE...IT APPEARS THIS
ACTIVITY IS ROOTED VERY NEAR OR SLIGHTLY NORTH OF WIND SHIFT AS WEAK
WARM ADVECTION SEEMS TO BE REQUIRED TO INITIATE CONVECTION.  LARGE
HAIL IS LIKELY WITH THIS ACTIVITY.

VERY DEEP BOUNDARY LAYER ACROSS TX SUGGESTS CONVECTIVE MODE IS
SLIGHTLY DIFFERENT WITH VERY HIGH BASED ACTIVITY DUE TO EXTREME SFC
HEATING.  MUCH WEAKER SHEAR IS RESULTING IN MORE MULTICELL STRUCTURE
WITH CONVECTIVE OUTFLOW STRONGLY INFLUENCING STORM PROPAGATION. 
RELATIVELY DRY SUB CLOUD LAYER FAVORS POTENTIAL FOR DAMAGING WINDS
IN ADDITION TO LARGE HAIL.

..DARROW.. 05/19/2003

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

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

31780050 33489910 34979803 36139682 35169611 31459881

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 19, 2:44 PM CDTMesoscale DiscussionSPCCaddo, Canadian, Cleveland, Comanche, Cotton, Garvin and 10 more91 min
May 19, 3:55 PM CDTMesoscale DiscussionSPCKay, Logan, Noble, Nowata, Osage, Pawnee and 2 more95 min
May 19, 4:05 PM CDTSevere Thunderstorm WatchSPCCarter, Cleveland, Coal, Cotton, Garvin, Grady and 12 more6 hr

Nearby

Mesoscale Discussions in Texas, 2003Mesoscale Discussions in Oklahoma, 2003Every 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.