Alert archive / Texas / Mesoscale Discussions in 2003
Mesoscale Discussion 540
The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2003, 10:30 AM CDT for 10 counties in Oklahoma; 47 counties in Texas. It was in force for 90 min.
The area
The outline as issued.
The facts
- Issued
- Apr 23, 2003, 10:30 AM CDT (15:30 UTC)
- Expired
- Apr 23, 2003, 12:00 PM CDT
- In force
- 90 min
- Issued by
- the Storm Prediction Center
All 57 counties
Beckham County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kiowa County, OK, Roger Mills County, OK, Washita County, OK, Armstrong County, TX, Baylor County, TX, Borden County, TX, Briscoe County, TX, Childress County, TX, Coke County, TX, Collingsworth County, TX, Concho County, TX, Cottle County, TX, Crosby County, TX, Dickens County, TX, Donley County, TX, Fisher County, TX, Floyd County, TX, Foard County, TX, Garza County, TX, Glasscock County, TX, Gray County, TX, Hall County, TX, Hardeman County, TX, Haskell County, TX, Hemphill County, TX, Howard County, TX, Irion County, TX, Jones County, TX, Kent County, TX, King County, TX, Knox County, TX, Lipscomb County, TX, Menard County, TX, Mitchell County, TX, Motley County, TX, Nolan County, TX, Ochiltree County, TX, Reagan County, TX, Roberts County, TX, Runnels County, TX, Schleicher County, TX, Scurry County, TX, Shackelford County, TX, Sterling County, TX, Stonewall County, TX, Taylor County, TX, Throckmorton County, TX, Tom Green County, TX, Wheeler County, TX, Wilbarger County, TX
The radar
The Lubbock radar (KLBB), 106 km from the middle of the area, began a volume at 15:33 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
Amarillo Airport, TX (KAMA), launched 12:00Z, 3.5 hours before the alert went out and 211 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.
- Mixed-layer CAPE
- 131 J/kg
- Mixed-layer CIN
- -181 J/kg
- Mixed-layer LCL
- 498 m above ground
- 0-6 km bulk shear
- 62 kt
- 0-1 km storm-relative helicity
- 230 m²/s²
- 0-3 km storm-relative helicity
- 254 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.7
The text
As transmitted, in the capitals the NWS used until 2016.
789 ACUS11 KWNS 231530 SWOMCD SPC MCD 231530 OKZ000-TXZ000-231700- MESOSCALE DISCUSSION 0540 NWS STORM PREDICTION CENTER NORMAN OK 1030 AM CDT WED APR 23 2003 AREAS AFFECTED...TX PANHANDLE SWD INTO WRN TX CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 231530Z - 231700Z STORMS WILL CONTINUE TO INCREASE IN INTENSITY THIS MORNING OVER THE TX PANHANDLE...WITH ADDITIONAL STORMS DEVELOPING SWD ALONG A SURFACE BOUNDARY INTO WRN TX. ONE OR MORE WW/S MAY BE NEEDED BY MIDDAY OR EARLY AFTERNOON. TRENDS IN WV IMAGERY/12Z UPPER AIR ANALYSIS SHOW AN UPPER CLOSED LOW IN THE VICINITY OF THE FOUR CORNERS REGION WITH LARGE SCALE ASCENT OVER WRN KS/WRN OK WWD TO WRN TX...WHERE UPPER LEVEL /500-250 MB/ FLOW IS DIVERGENT. SURFACE ANALYSIS/VIS IMAGERY SHOW A WELL DEFINED BOUNDARY EXTENDING FROM FAR SWRN KS SWD TO JUST W OF AMA TO NEAR INK...WITH SURFACE DEWPOINTS FALLING INTO THE 20S AND 30S TO THE WEST OF THIS BOUNDARY. A WARM FRONT EXTENDED EWD TO JUST S OF CDS AND INTO NRN TX. VIS IMAGERY ALSO SHOWS TCU BUILDING SWD FROM THE ONGOING STORMS OVER THE TX PANHANDLE...ALONG THE SURFACE BOUNDARY INTO WRN TX /WNW OF LBB/. AIR MASS WITHIN THE WARM SECTOR CONTINUES TO DESTABILIZE AS VIS IMAGERY SHOWS CLEARING SOUTH OF A LINE FROM LBB-DYS AND SURFACE DEWPOINTS RISING INTO THE LOWER 60S...RESULTING IN 100 MB MLCAPE VALUES OF 1000 J/KG. AS UVVS INCREASE OVER WRN TX INTO THE EARLY AFTERNOON WITH THE APPROACHING UPPER LOW...CONVERGENCE WILL INCREASE ALONG THE BOUNDARY OVER WRN TX TO SUPPORT DEEP CONVECTION. STRONG DEEP LAYER SHEAR AND MODERATE INSTABILITY WILL SUPPORT ORGANIZED SEVERE STORMS. SHEAR VECTORS NEARLY PARALLEL TO THE BOUNDARY OVER THE TX PANHANDLE INTO SWRN KS WILL FAVOR A LINE OF STORMS...WHILE A GREATER CHANCE FOR DISCRETE STORMS FARTHER S WHERE SHEAR VECTORS CROSS THE SURFACE BOUNDARY. ..PETERS.. 04/23/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...OUN...SJT...LUB...AMA...MAF... 30980196 33070177 35560125 36560079 36329895 34029893 30729983
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 23, 2:58 AM CDT | Mesoscale Discussion | SPC | Harmon | 2 hr |
| Apr 23, 9:55 AM CDT | Mesoscale Discussion | SPC | Alfalfa, Blaine, Caddo, Canadian, Cleveland, Creek and 17 more | 65 min |
| Apr 23, 11:50 AM CDT | Tornado Watch | SPC | Comanche, Cotton, Harmon, Jackson, Tillman | 6 hr |
| Apr 23, 1:20 PM CDT | Severe Thunderstorm Watch | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Custer and 15 more | 6 hr |
| Apr 23, 1:26 PM CDT | Mesoscale Discussion | SPC | Comanche, Cotton, Harmon, Jackson, Tillman | 94 min |
| Apr 23, 2:44 PM CDT | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Custer and 15 more | 91 min |
| Apr 23, 3:08 PM CDT | Mesoscale Discussion | SPC | Carter, Comanche, Cotton, Garvin, Jackson, Jefferson and 5 more | 97 min |
| Apr 23, 4:00 PM CDT | Tornado Watch | SPC | Atoka, Bryan, Carter, Jefferson, Johnston, Love and 3 more | 6 hr |
| Apr 23, 5:36 PM CDT | Mesoscale Discussion | SPC | Cotton, Tillman | 54 min |
| Apr 23, 5:47 PM CDT | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Comanche and 16 more | 88 min |
| Apr 23, 6:00 PM CDT | Tornado Watch | SPC | Comanche, Cotton, Stephens, Tillman | 4 hr |
| Apr 22, 7:32 PM CDT | Mesoscale Discussion | SPC | Gaines, Martin | 88 min |
| Apr 23, 12:04 AM CDT | Mesoscale Discussion | SPC | Andrews, Armstrong, Bailey, Borden, Briscoe, Carson and 27 more | 116 min |
| Apr 23, 1:05 AM CDT | Severe Thunderstorm Watch | SPC | Bailey, Castro, Cochran, Dallam, Deaf Smith, Hartley and 10 more | 6 hr |
| Apr 23, 3:59 AM CDT | Mesoscale Discussion | SPC | Bailey, Castro, Cochran, Deaf Smith, Hale, Hartley and 13 more | 2 hr |
| Apr 23, 2:12 PM CDT | Mesoscale Discussion | SPC | Bandera, Crockett, Edwards, Kerr, Kimble, Kinney and 7 more | 93 min |
| Apr 23, 2:35 PM CDT | Severe Thunderstorm Watch | SPC | Crockett, Edwards, Kimble, Kinney, Mason, Menard and 4 more | 5 hr |
| Apr 23, 4:02 PM CDT | Mesoscale Discussion | SPC | Crockett, Edwards, Kimble, Kinney, Mason, Menard and 5 more | 88 min |
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.