Alert archive / Texas / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 21, NWS Corpus Christi, TX

April 18, 2009La Salle County, Webb County, Texas

NWS Corpus Christi, TX issued this severe thunderstorm warning at Apr 18, 2009, 6:07 AM CDT for La Salle County, Webb County, Texas. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Apr 18, 2009, 6:07 AM CDT (11:07 UTC)
Expired: Apr 18, 2009, 6:36 AM CDT
In force: 29 min
Issued by: NWS Corpus Christi, TX
Area: Storm-based polygon

Counties La Salle County, TX, Webb County, TX

The radar

The Laughlin AFB radar (KDFX), 144 km from the middle of the area, began a volume at 11:10 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 18, 4:21 AM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 11.1 hours before the alert went out and 190 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3645 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: -21 m²/s²
0-3 km storm-relative helicity: 109 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.

000 
WUUS54 KCRP 181107
SVRCRP
TXC283-479-181200-
/O.NEW.KCRP.SV.W.0021.090418T1107Z-090418T1200Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
607 AM CDT SAT APR 18 2009

THE NATIONAL WEATHER SERVICE IN CORPUS CHRISTI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN LA SALLE COUNTY IN SOUTH TEXAS
  NORTH CENTRAL WEBB COUNTY IN SOUTH TEXAS

* UNTIL 700 AM CDT

* AT 606 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 15
  MILES WEST OF ARTESIA WELLS...OR 16 MILES NORTHWEST OF ENCINAL...
  AND MOVING EAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ARTESIA WELLS BY 645 AM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1100 AM CDT
SATURDAY MORNING FOR CENTRAL TEXAS.

&&

LAT...LON 2821 9940 2849 9940 2851 9906 2807 9904
      2805 9962 2821 9964
TIME...MOT...LOC 1106Z 260DEG 20KT 2821 9953

$$

TM

1 follow-up statement

000 
WWUS54 KCRP 181136
SVSCRP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CORPUS CHRISTI TX
636 AM CDT SAT APR 18 2009

TXC283-479-181144-
/O.CAN.KCRP.SV.W.0021.000000T0000Z-090418T1200Z/
LA SALLE-WEBB-
636 AM CDT SAT APR 18 2009

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WEBB AND WESTERN
LA SALLE COUNTIES IS CANCELLED...

THUNDERSTORMS IN THE AREA HAVE WEAKENED TO BELOW SEVERE 
LIMITS...THEREFORE THE SEVERE THUNDERSTORM WARNING HAS BEEN 
CANCELLED. HEAVY RAINFALL...DANGEROUS CLOUD TO GROUND LIGHTNING AND 
WINDS GUSTING TO 40 MPH WILL REMAIN POSSIBLE AS SEVERAL STRONG 
STORMS CONTINUE TO MOVE EAST AT 25 MPH ACROSS LASALLE COUNTY.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1100 AM CDT
SATURDAY MORNING FOR CENTRAL TEXAS.

LAT...LON 2821 9940 2849 9940 2851 9906 2807 9904
      2805 9962 2821 9964
TIME...MOT...LOC 1134Z 260DEG 20KT 2824 9936

$$

MJG

The office that day

Everything else NWS Corpus Christi, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 17, 7:43 PM CDT	Severe Thunderstorm Warning	CRP	Duval	32 min
Apr 17, 10:13 PM CDT	Severe Thunderstorm Warning	CRP	Webb	47 min
Apr 17, 10:58 PM CDT	Severe Thunderstorm Warning	CRP	Webb	47 min
Apr 17, 11:23 PM CDT	Severe Thunderstorm Warning	CRP	La Salle	52 min
Apr 18, 12:04 AM CDT	Severe Thunderstorm Warning	CRP	La Salle, McMullen	56 min
Apr 18, 4:36 AM CDT	Severe Thunderstorm Warning	CRP	Webb	54 min
Apr 18, 5:33 AM CDT	Severe Thunderstorm Warning	CRP	Webb	42 min
Apr 18, 3:34 PM CDT	River Flood Warning	CRP	Calhoun, Victoria	4 days
Apr 18, 3:34 PM CDT	River Flood Warning	CRP	Calhoun, Victoria	5 days

Nearby

Severe Thunderstorm Warnings in Texas, 2009 Every severe thunderstorm warning in 2009

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.