Alert archive / Texas / Flash Flood Warnings in 2000

Flash Flood Warning 11, NWS Houston/Galveston, TX

May 20, 2000Harris County, Liberty County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at May 20, 2000, 4:59 AM CDT for Harris County, Liberty County, Texas. It was in force for 3 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
May 20, 2000, 4:59 AM CDT (09:59 UTC)
Expired
May 20, 2000, 8:00 AM CDT
In force
3 hr
Issued by
NWS Houston/Galveston, TX
Area
Whole counties

Counties Harris County, TX, Liberty County, TX

The radar

The Houston radar (KHGX), 59 km from the middle of the area, began a volume at 10:03 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, 10.0 hours before the alert went out and 183 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 2000-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 701 joules per kilogram.LCLLFCEL10008507005003002001001 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 2000-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -31 square meters per square second.19395878Sfc1 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
701 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1188 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-31 m²/s²
0-3 km storm-relative helicity
32 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS54 KHGX 201004
FFWHGX
TXC201-291-201300-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
459 AM CDT SAT MAY 20 2000

THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON TX HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  EASTERN HARRIS COUNTY IN SOUTHEAST TEXAS
  SOUTHERN LIBERTY COUNTY IN SOUTHEAST TEXAS

* UNTIL 800 AM CDT

* AT 456 AM CDT...RAINFALL WAS SLOWLY COMING TO AN END OVER THE
  FLASH FLOOD WARNING AREA.  ADDITIONAL 1/4 TO 1/2 INCH AMOUNTS
  MAY OCCUR. THE PREVIOUS HEAVY RAINFALL OF 6 TO 9 INCHES IN
  EASTERN HARRIS COUNTY AND THE 12 TO 19 INCHES ACROSS SOUTHERN
  LIBERTY COUNTY WILL TAKE TIME TO RECEDE.

* FLOODING IS EXPECTED TO CONTINUE IN EASTERN HARRIS AND SOUTHERN
  LIBERTY COUNTY...AREAS ESPECIALLY HARD HIT INCLUDE DAYTON...
  LIBERTY AND AMES.

STAY AWAY FROM SMALL CREEKS...STREAMS...BAYOUS...UNDERPASSES...AND
FEEDER ROADS. DO NOT CROSS ANY LOC;ATION WHERE WATER COVERS THE ROAD!

PLEASE REPORT FLOODING TO THE COUNTY SHERIFF...LOCAL POLICE...OR
DEPARTMENT OF PUBLIC SAFETY. THEY WILL RELAY YOUR REPORT TO THE
NATIONAL WEATHER SERVICE.

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 May 20, 2:41 AM CDT, 2 hours 18 minutes earlier.

Area forecast discussion, May 20, 2:41 AM CDT, 2 hours 18 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
241 AM CDT SAT MAY 20 2000

A RATHER BUSY NIGHT HERE AT HGX. AS OF 06Z...IAH RECEIVED 6.87
INCHES OF RAIN (NEW 24 HR RAINFALL RECORD)...HOOKS AIRPORT RECEIVED
4.81 INCHES BUT THE BIG WINNER (LOSER) WAS LIBERTY WHICH RECEIVED
18.3 INCHES OF RAIN SINCE ABOUT 830 PM LAST NIGHT...AND STILL
RAINING. IR IMAGERY SHOWS CLOUD TEMPS VERY COLD WITH A GRADUAL
WARMING TREND NOTED. WV IMAGERY SHOWS UPPER LOW MOVING EAST AS
UPSTREAM KICKER OFF THE WEST COAST PUSHES SE. AS THE UPPER LOW
PUSHES EAST...BEST UPPER LEVEL DIVERGENCE WILL ALSO SHIFT EAST.
CURRENT THINKING IS THAT THE MCS OVER THE REGION WILL PUSH OFFSHORE BY
10Z WITH PERIODS OF LIGHT TO MODERATE RAIN CONTINUING THROUGH THE
MORNING. SUBSIDENCE IN THE WAKE OF THIS SYSTEM WILL STABILIZE THE
ATMOSPHERE LATE THIS AFTERNOON AND TONIGHT. TEMPS TODAY WILL BE A
BIT TRICKY DUE TO CONVECTIVE CLOUD DEBRIS. IF SKIES CLEAR TONIGHT...
FOG PROBABLY A GOOD BET.

WILL DROP FFA AS CONVECTION WANES BUT FLOODING/RIVER FLOODING WILL
PERSIST. BE AWARE THAT AREAS NORTH OF I-10 FROM NORTHERN HARRIS TO
LIBERTY COUNTY WILL LIKELY REMAIN DANGEROUS.

SUNDAY IS A BIT TRICKY AS WELL. AT FIRST GLANCE...SUNDAY LOOKS
FAIRLY DRY BUT THE ETA/AVN BRINGS A FAIRLY POTENT S/WV THROUGH THE
REGION BETWEEN 18-00Z. FCST MDL SOUNDINGS INDICATE K INDICES AROUND
30 AND PWS BEGIN TO POOL AND INCREASE TO 1.5 TO 1.6 INCHES.
SOUNDINGS ALSO SHOW THAT THE AREA IS UNCAPPED. THINK TSTM CHANCES
WILL INCREASE SUNDAY AFTERNOON AS THIS NEXT S/WV APPROACHES.

EXTENDED: RIDGE BUILDS INTO THE REGION AND EXPECT A BIT OF A DRYING
TREND WITH WARMER TEMPERATURES. LOOKING AHEAD TO MEMORIAL DAY
WEEKEND...AN UPPER LOW MOVES TOWARD TEXAS WITH INCREASING RAIN
CHANCES SAT-SUN.

.KHGX...NONE.

43/45/41/36/48/DEB

CLL BB 085/066 087/067 089 3-4
IAH EB 083/066 088/066 089 5-4
GLS EB 081/068 082/067 082 6-3

In the hours before

Local storm report, May 20, 3:01 AM CDT, 1 hour 58 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
301 AM CDT SAT MAY 20 2000

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0600 PM    (IAH)HOUSTON INTL ARPT    TX   FLOOD
05/19/00   HARRIS                         ONE FOOT OF WATER IN
                                          IAH APPROACH CONTROL
                                          FACILITY REPORTED BY
                                          CWSU.

1050 PM    5 E DANCIGER              TX   TSTM WIND
05/19/00   BRAZORIA                       SHERIFF'S OFFICE
                                          REPORTED TREES UPROOTED
                                          ALONG FM 1301 BETWEEN
                                          DANCIGER AND WEST
                                          COLUMBIA.

1105 PM    DAYTON                    TX   FLOOD
05/19/00   LIBERTY                        EXTENSIVE STREET
                                          FLOODING REPORTED BY
                                          SHERIFF'S OFFICE.

1150 PM    LIBERTY                   TX   FLOOD
05/19/00   LIBERTY                        MEDIA REPORTED 1 TO 2
                                          FEET OF WATER ON 50
                                          PERCENT OF AREA ROADS.

1210 AM    1 E WALLER                TX   FLOOD
05/20/00   WALLER                         SHERIFF'S OFFICE
                                          REPORTED 10 INCHES OF
                                          WATER AT HWY 290 BYPASS
                                          AND FM 1098 AND ON
                                          FM 362 AND KICKAPOO ROAD.

1230 AM    LIBERTY                   TX   FLOOD
05/20/00   LIBERTY                        MEDIA REPORTED NUMEROUS
                                          VEHICLES FLOODED.

1230 AM    DAYTON                    TX   FLOOD
05/20/00   LIBERTY                        SHERIFF'S OFFICE
                                          REPORTED WATER IN HOMES.

1230 AM    DAYTON                    TX   TSTM WIND
05/20/00   LIBERTY                        SHERIFF'S OFFICE
                                          REPORTED POWER LINES
                                          DOWN.

1230 AM    LIBERTY                   TX    MPH TSTM GUST
05/20/00   LIBERTY                        SHERIFF'S OFFICE
                                          REPORTED POWER LINES
                                          DOWN.

N

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 7:25 PM CDTSevere Thunderstorm WarningHGXHarris35 min
May 19, 8:46 PM CDTTornado WarningHGXLiberty59 min
May 19, 8:49 PM CDTFlash Flood WarningHGXHarris, Liberty116 min
May 19, 9:20 PM CDTFlash Flood WarningHGXWaller3 hr
May 19, 10:35 PM CDTFlash Flood WarningHGXHarris, Liberty, Montgomery100 min
May 19, 10:45 PM CDTTornado WarningHGXBrazoria45 min
May 19, 11:17 PM CDTSevere Thunderstorm WarningHGXLiberty43 min
May 19, 11:25 PM CDTTornado WarningHGXBrazoria50 min
May 19, 11:30 PM CDTTornado WarningHGXLiberty30 min
May 19, 11:33 PM CDTFlash Flood WarningHGXBrazoria3 hr
May 20, 12:00 AM CDTFlash Flood WarningHGXBrazoria, Chambers, Fort Bend, Harris, Liberty, Waller and 1 more5 hr
May 20, 12:25 AM CDTTornado WarningHGXChambers, Liberty65 min
May 20, 2:02 AM CDTSevere Thunderstorm WarningHGXGalveston28 min
May 20, 2:22 AM CDTTornado WarningHGXChambers, Galveston38 min

Nearby

Flash Flood Warnings in Texas, 2000Every flash flood warning in 2000

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.