Alert archive / Texas / Flash Flood Warnings in 2013

Flash Flood Warning 12, NWS Houston/Galveston, TX

September 20, 2013Fort Bend County, Harris County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Sep 20, 2013, 10:11 PM CDT for Fort Bend County, Harris County, Texas. It was in force for 2 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
Sep 20, 2013, 10:11 PM CDT (03:11 UTC)
Expired
Sep 21, 2013, 12:15 AM CDT
In force
2 hr
Issued by
NWS Houston/Galveston, TX
Area
Storm-based polygon
Flood severity
None

Counties Fort Bend County, TX, Harris County, TX

The radar

The Houston radar (KHGX), 54 km from the middle of the area, began a volume at 03:12 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

Lake Charles Mun, LA (KLCH), launched 00:00Z, 3.2 hours before the alert went out and 234 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, Lake Charles Mun, LA at 00:00Z on 2013-09-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2607 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 00:00Z on 2013-09-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 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
2607 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
600 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
147 m²/s²
Significant tornado parameter
1.5
Supercell composite
8.8

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Houston/Galveston, TX wrote its last area forecast discussion before this flash flood warning went out at Sep 20, 9:29 PM CDT, 42 minutes earlier.

Area forecast discussion, Sep 20, 9:29 PM CDT, 42 minutes before
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Hazardous weather outlook, Sep 20, 4:46 AM CDT, 17 hours 25 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
446 AM CDT FRI SEP 20 2013

TXZ163-164-176>179-195>200-210>212-226-227-211200-
AUSTIN-BRAZOS-BURLESON-COLORADO-FORT BEND-GRIMES-HOUSTON-LIBERTY-
MADISON-MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-
WASHINGTON-WHARTON-
446 AM CDT FRI SEP 20 2013

...LOCALLY HEAVY RAINFALL POSSIBLE THROUGH SATURDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

EXPECT INCREASING SHOWER AND THUNDERSTORM COVERAGE AS HIGH MOISTURE
LEVELS PERSIST AND A SLOW MOVING COLD FRONT SAGS SOUTHWARD ACROSS THE
AREA. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE...ESPECIALLY LATER THIS
AFTERNOON THROUGH TONIGHT...AND A FLASH FLOOD WATCH MIGHT BE NEEDED.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SHOWERS AND THUNDERSTORMS ALONG WITH SOME LOCALLY HEAVY RAINFALL ARE
EXPECTED ON SATURDAY MORNING AS A SLOW MOVING COLD FRONT SAGS SOUTHWARD
TOWARD THE COAST. FOR THIS FRIDAY THROUGH SATURDAY EVENT...RAINFALL
TOTALS OF 2 TO 4 INCHES CAN BE EXPECTED WHERE THE BEST CELL TRAINING
SETS UP...AND SOME AMOUNTS GREATER THAN 5 INCHES WILL BE POSSIBLE THAT
COULD LEAD TO SOME LOCALIZED FLOODING.

WE WILL CONTINUE TO MONITOR THE TROPICAL DISTURBANCE IN THE BAY OF
CAMPECHE FOR POSSIBLE TROPICAL DEVELOPMENT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON THROUGH
SATURDAY MORNING.

GMZ330-335-350-355-370-375-TXZ213-214-235>238-211200-
BRAZORIA-CHAMBERS-GALVESTON-GALVESTON BAY-HARRIS-JACKSON-
MATAGORDA-MATAGORDA BAY-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM-
WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM-
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM-
446 AM CDT FRI SEP 20 2013

...LOCALLY HEAVY RAINFALL POSSIBLE THROUGH SATURDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

EXPECT INCREASING SHOWER AND THUNDERSTORM COVERAGE AS HIGH MOISTURE
LEVELS PERSIST AND A SLOW MOVING COLD FRONT SAGS SOUTHWARD ACROSS
THE AREA. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE...ESPECIALLY LATER
THIS AFTERNOON UP NORTH AND THEN AREA WIDE TONIGHT...AND A FLASH
FLOOD WATCH MIGHT BE NEEDED. ABOVE NORMAL TIDE LEVELS ARE EXPECTED
TO PERSIST...AND WATER MAY APPROACH THE LOWEST AND MOST SUSCEPTIBLE
BEACHFRONT ROADS RIGHT AROUND HIGH TIDE TODAY. LARGER SURF AND
STRONGER RIP CURRENTS CAN ALSO BE EXPECTED.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SHOWERS AND THUNDERSTORMS ALONG WITH SOME LOCALLY HEAVY RAINFALL ARE
EXPECTED ON SATURDAY MORNING AS A SLOW MOVING COLD FRONT SAGS SOUTHWARD
TOWARD THE COAST. FOR THIS FRIDAY THROUGH SATURDAY EVENT...RAINFALL
TOTALS OF 2 TO 4 INCHES CAN BE EXPECTED WHERE THE BEST CELL TRAINING
SETS UP...AND SOME AMOUNTS GREATER THAN 5 INCHES WILL BE POSSIBLE
THAT COULD LEAD TO SOME LOCALIZED FLOODING.

TIDES WILL BE RUNNING AROUND 1.5 FEET ABOVE NORMAL ON SATURDAY AT
BEACHFRONT LOCATIONS. AT THESE LEVELS...WATER MAY APPROACH THE LOWEST
AND MOST SUSCEPTIBLE BEACHFRONT ROADS RIGHT AROUND HIGH TIDE ON SATURDAY
EVENING. LARGER SURF AND STRONGER RIP CURRENTS CAN ALSO BE EXPECTED.

WE WILL CONTINUE TO MONITOR THE TROPICAL DISTURBANCE IN THE BAY OF
CAMPECHE FOR POSSIBLE TROPICAL DEVELOPMENT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON THROUGH
SATURDAY MORNING.

The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 20, 8:52 PM CDTAreal Flood AdvisoryHGXFort Bend, Harris, Montgomery113 min
Sep 20, 10:11 PM CDTSmall Craft AdvisoryHGX7 hr
Sep 20, 10:22 PM CDTRiver Flood WarningHGXHarris6 days
Sep 20, 11:05 PM CDTSpecial Marine WarningHGX40 min
Sep 21, 5:05 AM CDTSmall Craft AdvisoryHGX44 hr

Nearby

Flash Flood Warnings in Texas, 2013Every flash flood warning in 2013

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.