Alert archive / Texas / Mesoscale Discussions in 2003
Mesoscale Discussion 103
The Storm Prediction Center issued this mesoscale discussion at Feb 21, 2003, 3:53 AM CST for 19 counties in Texas. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 21, 2003, 3:53 AM CST (09:53 UTC)
- Expired
- Feb 21, 2003, 6:30 AM CST
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
Counties Aransas County, TX, Austin County, TX, Brazoria County, TX, Calhoun County, TX, Colorado County, TX, Fort Bend County, TX, Goliad County, TX, Harris County, TX, Jackson County, TX, Kleberg County, TX, Lavaca County, TX, Matagorda County, TX, Montgomery County, TX, Nueces County, TX, Refugio County, TX, San Patricio County, TX, Victoria County, TX, Waller County, TX, Wharton County, TX
The radar
The Corpus Christi radar (KCRP), 110 km from the middle of the area, began a volume at 09:54 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
Corpus Christi, TX (KCRP), launched 00:00Z, 9.9 hours before the alert went out and 104 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
- 962 J/kg
- Mixed-layer CIN
- -35 J/kg
- Mixed-layer LCL
- 623 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 98 m²/s²
- 0-3 km storm-relative helicity
- 140 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 2.7
The text
As transmitted, in the capitals the NWS used until 2016.
178 ACUS11 KWNS 210953 SWOMCD SPC MCD 210953 TXZ000-211230- MESOSCALE DISCUSSION 0103 NWS STORM PREDICTION CENTER NORMAN OK 0353 AM CST FRI FEB 21 2003 AREAS AFFECTED...MIDDLE TX COAST CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 210953Z - 211230Z THUNDERSTORMS FORECAST TO INCREASE INVOF THE MIDDLE TX COAST. DAMAGING WINDS AND AN ISOLATED TORNADO POSSIBLE WITH NEAR SURFACE-BASED STORMS CLOSE TO THE COAST...ALONG WITH HAIL THREAT WHICH EXTENDS FURTHER INLAND WHERE STORMS WILL REMAIN MORE ELEVATED. WW MAY BE REQUIRED BY 11Z. SHOWERS AND THUNDERSTORMS CONTINUE TO INCREASE ACROSS PARTS OF CENTRAL AND SRN TX AHEAD OF APPROACHING UPPER LOW NOW OVER NWRN MEXICO. STEEP MID-LEVEL LAPSE RATES ARE IN PLACE ACROSS THE REGION...AND CONTINUED LOW-LEVEL WARMING / MOISTENING ASSOCIATED WITH SLY LOW-LEVEL JET SHOULD ALLOW AIRMASS TO CONTINUE TO DESTABILIZE. ALTHOUGH BOUNDARY BETWEEN HIGH THETA-E GULF AIR AND COOLER CONTINENTAL AIRMASS APPEARS TO BE JUST OFFSHORE...SHALLOW COOL AIR ALONG THE COAST SUGGESTS THAT NEAR SURFACE-BASED STORMS MAY DEVELOP. ADDITIONALLY...SURFACE LOW APPEARS TO BE DEVELOPING SOUTH OF CRP WHICH MAY ALLOW THIS BOUNDARY TO CREEP INLAND INCREASING THE THREAT FOR SURFACE-BASED STORMS. DEEP-LAYER WIND FIELD IS SUPPORTIVE OF SEVERE STORMS / SUPERCELLS. LARGE HAIL WILL BE THE MAIN THREAT AWAY FROM THE COAST WHERE STORMS SHOULD REMAIN ELEVATED. HOWEVER...DAMAGING WINDS WILL BE POSSIBLE WITH LESS-ELEVATED STORMS NEARER THE COAST. AN ISOLATED TORNADO COULD ALSO OCCUR -- PARTICULARLY IF HIGHER THETA-E AIRMASS MOVES ONSHORE. ..GOSS.. 02/21/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... 27389741 27359763 27539785 28509752 29719690 30499561 29899509 28969528 28419633 27879703
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 21, 1:43 AM CST | Mesoscale Discussion | SPC | Chambers, Hardin, Jasper, Jefferson, Liberty, Newton and 1 more | 2 hr |
| Feb 21, 2:43 AM CST | Mesoscale Discussion | SPC | Dimmit, Edwards, Frio, Kinney, La Salle, Maverick and 5 more | 3 hr |
| Feb 21, 4:10 AM CST | Severe Thunderstorm Watch | SPC | Atascosa, Bandera, Bastrop, Bexar, Blanco, Brazos and 26 more | 6 hr |
| Feb 21, 4:25 AM CST | Tornado Watch | SPC | Austin, Brazoria, Brazos, Burleson, Calhoun, Colorado and 15 more | 6 hr |
| Feb 21, 5:58 AM CST | Mesoscale Discussion | SPC | Atascosa, Bandera, Bastrop, Bexar, Blanco, Brazos and 26 more | 2 hr |
| Feb 21, 6:16 AM CST | Mesoscale Discussion | SPC | Austin, Brazoria, Brazos, Burleson, Calhoun, Colorado and 17 more | 119 min |
| Feb 21, 9:02 AM CST | Mesoscale Discussion | SPC | Angelina, Brazoria, Chambers, Cherokee, Fort Bend, Galveston and 22 more | 58 min |
| Feb 21, 9:40 AM CST | Tornado Watch | SPC | Angelina, Austin, Brazoria, Brazos, Burleson, Chambers and 25 more | 6 hr |
| Feb 21, 11:47 AM CST | Mesoscale Discussion | SPC | Angelina, Brazoria, Chambers, Fort Bend, Galveston, Grimes and 18 more | 118 min |
| Feb 21, 1:30 PM CST | Mesoscale Discussion | SPC | Hardin, Harris, Jasper, Liberty, Montgomery, Newton and 3 more | 2 hr |
| Feb 21, 3:32 PM CST | Mesoscale Discussion | SPC | Hardin, Jasper, Liberty, Newton, Orange, Tyler | 118 min |
| Feb 21, 3:40 PM CST | Tornado Watch | SPC | Angelina, Chambers, Hardin, Jasper, Jefferson, Nacogdoches and 5 more | 6 hr |
| Feb 21, 5:50 PM CST | Mesoscale Discussion | SPC | Angelina, Chambers, Hardin, Jasper, Jefferson, Nacogdoches and 5 more | 115 min |
Nearby
Mesoscale Discussions in Texas, 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.