Alert archive / Texas / Red Flag Warnings in 2011

Red Flag Warning 15, NWS Austin/San Antonio, TX

April 18, 201117 counties in Texas

NWS Austin/San Antonio, TX issued this red flag warning at Apr 18, 2011, 1:21 PM CDT for 17 counties in Texas. It took effect at Apr 19, 2011, 10:00 AM CDT. It was in force for 10 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 18, 2011, 1:21 PM CDT (18:21 UTC)
In effect from
Apr 19, 2011, 10:00 AM CDT
Expired
Apr 19, 2011, 8:00 PM CDT
In force
10 hr
Issued by
NWS Austin/San Antonio, TX

Counties Bandera County, TX, Blanco County, TX, Burnet County, TX, Dimmit County, TX, Edwards County, TX, Frio County, TX, Gillespie County, TX, Kendall County, TX, Kerr County, TX, Kinney County, TX, Llano County, TX, Maverick County, TX, Medina County, TX, Real County, TX, Uvalde County, TX, Val Verde County, TX, Zavala County, TX

The radar

The Laughlin AFB radar (KDFX), 90 km from the middle of the area, began a volume at 18:27 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 nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 6.4 hours before the alert went out and 137 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, Del Rio, TX at 12:00Z on 2011-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2447 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Del Rio, TX at 12:00Z on 2011-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 257 square meters per square second.193958Sfc1 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
2447 J/kg
Mixed-layer CIN
-310 J/kg
Mixed-layer LCL
656 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
257 m²/s²
0-3 km storm-relative helicity
302 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.

124 
WWUS84 KEWX 181821
RFWEWX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
121 PM CDT MON APR 18 2011

...A RED FLAG WARNING IS IN EFFECT FROM 10 AM CDT TUESDAY UNTIL
8 PM CDT FOR THE HILL COUNTRY...EDWARDS PLATEAU...AND RIO GRANDE
PLAINS DUE TO BREEZY AND VERY DRY CONDITIONS...

.AN UPPER LEVEL LOW PRESSURE SYSTEM MOVING EASTWARD ACROSS THE
GREAT PLAINS WILL CAUSE THE DRYLINE TO PUSH EASTWARD INTO SOUTH
CENTRAL TEXAS ON TUESDAY. VERY DRY AND BREEZY WEST TO SOUTHWEST
WINDS OF 15 TO 20 MPH WILL MIX DOWN TO THE SURFACE BEHIND THE
DRYLINE. AFTERNOON RELATIVE HUMIDITIES WILL FALL TO NEAR 25
PERCENT ALONG HIGHWAY 281...AND INTO THE SINGLE DIGITS ACROSS
WESTERN PORTIONS OF THE REGION. THIS WILL RESULT IN CRITICAL FIRE
WEATHER CONDITIONS LATE TUESDAY MORNING THROUGH TUESDAY EVENING.

TXZ171-172-183>190-202>204-217>219-228-191115-
/O.UPG.KEWX.FW.A.0007.110419T1500Z-110420T0100Z/
/O.NEW.KEWX.FW.W.0015.110419T1500Z-110420T0100Z/
LLANO-BURNET-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-GILLESPIE-
KENDALL-BLANCO-KINNEY-UVALDE-MEDINA-MAVERICK-ZAVALA-FRIO-DIMMIT-
121 PM CDT MON APR 18 2011

...RED FLAG WARNING IN EFFECT FROM 10 AM TO 8 PM CDT TUESDAY...

THE NATIONAL WEATHER SERVICE IN AUSTIN/SAN ANTONIO HAS ISSUED A
RED FLAG WARNING...WHICH IS IN EFFECT FROM 10 AM TO 8 PM CDT
TUESDAY. THE FIRE WEATHER WATCH IS NO LONGER IN EFFECT. 

AN UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE EASTWARD ACROSS THE
GREAT PLAINS CAUSING THE DRYLINE TO PUSH EASTWARD INTO SOUTH CENTRAL
TEXAS ON TUESDAY. VERY DRY AND BREEZY WEST TO SOUTHWEST WINDS WILL
MIX DOWN TO THE SURFACE BEHIND THE DRYLINE. RELATIVE HUMIDITIES
ARE EXPECTED TO FALL TO NEAR 20 PERCENT ACROSS WESTERN PORTIONS OF
THE REGION BY LATE TUESDAY MORNING. BY EARLY AFTERNOON...RELATIVE
HUMIDITIES WILL FALL TO 20 TO 25 PERCENT ALONG HIGHWAY 281...AND
INTO THE TEENS AND SINGLE DIGITS ACROSS WESTERN PORTIONS OF THE
REGION. WEST TO SOUTHWEST WINDS OF 15 TO 20 MPH WILL COMBINE WITH
THE VERY DRY CONDITIONS TO RESULT IN CRITICAL FIRE WEATHER CONDITIONS.
WINDS WILL GRADUALLY DECREASE THROUGH THE EVENING BUT RELATIVE
HUMIDITIES WILL BE SLOW TO RECOVER OVERNIGHT..

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS WEATHER CONDITIONS WILL PROMOTE FIRES
THAT ARE DIFFICULT TO CONTROL ACROSS THE WARNED AREA. A RED FLAG
WARNING IS COMPLETELY SEPARATE FROM A LOCAL BURN BAN WHICH IS
ISSUED BY LOCAL OFFICIALS.

&&

$$
3 follow-up statements
823 
WWUS84 KEWX 191112
RFWEWX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
612 AM CDT TUE APR 19 2011

...A RED FLAG WARNING IS IN EFFECT FROM 10 AM CDT TODAY UNTIL 8 PM
CDT TONIGHT FOR THE HILL COUNTRY...EDWARDS PLATEAU...AND RIO
GRANDE PLAINS DUE TO BREEZY AND VERY DRY CONDITIONS...

.AN UPPER LEVEL LOW PRESSURE SYSTEM MOVING EASTWARD ACROSS THE
GREAT PLAINS WILL CAUSE THE DRYLINE TO PUSH EASTWARD INTO SOUTH
CENTRAL TEXAS TODAY. VERY DRY AND BREEZY WEST TO SOUTHWEST
WINDS OF 15 TO 20 MPH WILL MIX DOWN TO THE SURFACE BEHIND THE
DRYLINE. AFTERNOON RELATIVE HUMIDITIES WILL FALL TO NEAR
25 PERCENT ALONG HIGHWAY 281...AND INTO THE SINGLE DIGITS ACROSS
WESTERN PORTIONS OF THE REGION. THIS WILL RESULT IN CRITICAL FIRE
WEATHER CONDITIONS LATE THIS MORNING THROUGH THIS EVENING.

TXZ171-172-183>190-202>204-217>219-228-192300-
/O.CON.KEWX.FW.W.0015.110419T1500Z-110420T0100Z/
LLANO-BURNET-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-GILLESPIE-
KENDALL-BLANCO-KINNEY-UVALDE-MEDINA-MAVERICK-ZAVALA-FRIO-DIMMIT-
612 AM CDT TUE APR 19 2011

...RED FLAG WARNING REMAINS IN EFFECT FROM 10 AM THIS MORNING TO
8 PM CDT THIS EVENING...

AN UPPER LEVEL LOW PRESSURE SYSTEM WILL MOVE EASTWARD ACROSS THE
GREAT PLAINS CAUSING THE DRYLINE TO PUSH EASTWARD INTO SOUTH
CENTRAL TEXAS TODAY. VERY DRY AND BREEZY WEST TO SOUTHWEST
WINDS WILL MIX DOWN TO THE SURFACE BEHIND THE DRYLINE. RELATIVE
HUMIDITIES ARE EXPECTED TO FALL TO NEAR 20 PERCENT ACROSS WESTERN
PORTIONS OF THE REGION BY LATE THIS MORNING. BY EARLY
AFTERNOON...RELATIVE HUMIDITIES WILL FALL TO 20 TO 25 PERCENT
ALONG HIGHWAY 281...AND INTO THE TEENS AND SINGLE DIGITS ACROSS
WESTERN PORTIONS OF THE REGION. WEST TO SOUTHWEST WINDS OF 15 TO
20 MPH WILL COMBINE WITH THE VERY DRY CONDITIONS TO RESULT IN
CRITICAL FIRE WEATHER CONDITIONS. WINDS WILL GRADUALLY DECREASE
THROUGH THE EVENING BUT RELATIVE HUMIDITIES WILL BE SLOW TO
RECOVER OVERNIGHT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS WEATHER CONDITIONS WILL PROMOTE FIRES
THAT ARE DIFFICULT TO CONTROL ACROSS THE WARNED AREA. A RED FLAG
WARNING IS COMPLETELY SEPARATE FROM A LOCAL BURN BAN WHICH IS
ISSUED BY LOCAL OFFICIALS.

&&

$$
706 
WWUS84 KEWX 192057
RFWEWX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
357 PM CDT TUE APR 19 2011

...A RED FLAG WARNING CONTINUES IN EFFECT UNTIL 8 PM CDT TONIGHT
FOR THE HILL COUNTRY...EDWARDS PLATEAU...AND RIO GRANDE PLAINS DUE
TO BREEZY AND VERY DRY CONDITIONS...

.A DRY-LINE MOVING ACROSS THE NORTHERN PORTION OF THE HILL COUNTRY
AND THE UPPER RIO GRANDE PLAINS AREAS IS PRODUCING VERY DRY
CONDITIONS AND WEST TO SOUTHWEST WINDS OF 10 TO 20 MPH. THIS WILL
RESULT IN CRITICAL FIRE WEATHER CONDITIONS THROUGH THIS EVENING.

TXZ171-172-183>190-202>204-217>219-228-200100-
/O.CON.KEWX.FW.W.0015.000000T0000Z-110420T0100Z/
LLANO-BURNET-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-GILLESPIE-
KENDALL-BLANCO-KINNEY-UVALDE-MEDINA-MAVERICK-ZAVALA-FRIO-DIMMIT-
357 PM CDT TUE APR 19 2011

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS
EVENING...

A RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS WEATHER CONDITIONS WILL PROMOTE FIRES
THAT ARE DIFFICULT TO CONTROL ACROSS THE WARNED AREA. A RED FLAG
WARNING IS COMPLETELY SEPARATE FROM A LOCAL BURN BAN WHICH IS
ISSUED BY LOCAL OFFICIALS.

&&

$$
264 
WWUS84 KEWX 192123 CCA
RFWEWX

URGENT - FIRE WEATHER MESSAGE...CORRECTED
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
412 PM CDT TUE APR 19 2011

...A RED FLAG WARNING CONTINUES IN EFFECT UNTIL 8 PM CDT TONIGHT
FOR THE HILL COUNTRY...EDWARDS PLATEAU...AND RIO GRANDE PLAINS DUE
TO BREEZY AND VERY DRY CONDITIONS...

.A DRY-LINE MOVING ACROSS THE NORTHERN PORTION OF THE HILL COUNTRY
AND THE UPPER RIO GRANDE PLAINS AREAS IS PRODUCING VERY DRY
CONDITIONS AND WEST TO SOUTHWEST WINDS OF 10 TO 20 MPH. 

TXZ171-172-183>190-202>204-217>219-228-200100-
/O.COR.KEWX.FW.W.0015.000000T0000Z-110420T0100Z/
LLANO-BURNET-VAL VERDE-EDWARDS-REAL-KERR-BANDERA-GILLESPIE-
KENDALL-BLANCO-KINNEY-UVALDE-MEDINA-MAVERICK-ZAVALA-FRIO-DIMMIT-
412 PM CDT TUE APR 19 2011

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS
EVENING...

A DRY-LINE MOVING ACROSS THE NORTHERN PORTION OF THE HILL COUNTRY
AND THE UPPER RIO GRANDE PLAINS AREAS IS PRODUCING VERY DRY
CONDITIONS AND WEST TO SOUTHWEST WINDS OF 10 TO 20 MPH. CRITICAL
FIRE WEATHER CONDITIONS WILL REMAIN POSSIBLE OVER SOME AREAS
THROUGH EARLY THIS EVENING.

IN ADDITION TO THE BREEZY AND DRY CONDITIONS...ISOLATED
THUNDERSTORMS WITH VERY GUSTY WINDS WILL BE POSSIBLE THIS EVENING. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS WEATHER CONDITIONS WILL PROMOTE FIRES
THAT ARE DIFFICULT TO CONTROL ACROSS THE WARNED AREA. A RED FLAG
WARNING IS COMPLETELY SEPARATE FROM A LOCAL BURN BAN WHICH IS
ISSUED BY LOCAL OFFICIALS.

&&

$$

The office that day

Everything else NWS Austin/San Antonio, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 18, 4:19 AM CDTFire Weather WatchEWXBandera, Blanco, Burnet, Dimmit, Edwards, Frio and 11 more9 hr

Nearby

Red Flag Warnings in Texas, 2011Every red flag warning in 2011

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.