Alert archive / Texas / Flash Flood Warnings in 2016

Flash Flood Warning 21, NWS Houston/Galveston, TX

April 18, 201620 counties in Texas

NWS Houston/Galveston, TX issued this flash flood warning at Apr 18, 2016, 8:55 AM CDT for 20 counties in Texas. It was in force for 4 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 18, 2016, 8:55 AM CDT (13:55 UTC)
Expired: Apr 18, 2016, 1:00 PM CDT
In force: 4 hr
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon
Flood severity: None

Counties Austin County, TX, Brazoria County, TX, Brazos County, TX, Chambers County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Grimes County, TX, Harris County, TX, Houston County, TX, Liberty County, TX, Madison County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Trinity County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 78 km from the middle of the area, began a volume at 13:54 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.

What was reported inside it

Time	Report	Where	Remark
Apr 18, 10:23 AM CDT	FLASH FLOOD	Galveston, TX	WATER INUNDATING NUMEROUS ROADWAYS WITHIN THE CITY OF GALVESTON.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 1.9 hours before the alert went out and 214 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: 283 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 517 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 174 m²/s²
0-3 km storm-relative helicity: 231 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

As transmitted.

713 
WGUS54 KHGX 181355
FFWHGX
TXC015-039-041-071-089-157-167-185-201-225-291-313-339-373-407-455-
471-473-477-481-181800-
/O.NEW.KHGX.FF.W.0021.160418T1355Z-160418T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
855 AM CDT MON APR 18 2016

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL WHARTON COUNTY IN SOUTHEASTERN TEXAS...
  WASHINGTON COUNTY IN SOUTHEASTERN TEXAS...
  HARRIS COUNTY IN SOUTHEASTERN TEXAS...
  WALKER COUNTY IN SOUTHEASTERN TEXAS...
  WALLER COUNTY IN SOUTHEASTERN TEXAS...
  GALVESTON COUNTY IN SOUTHEASTERN TEXAS...
  CHAMBERS COUNTY IN SOUTHEASTERN TEXAS...
  GRIMES COUNTY IN SOUTHEASTERN TEXAS...
  NORTHERN BRAZORIA COUNTY IN SOUTHEASTERN TEXAS...
  FORT BEND COUNTY IN SOUTHEASTERN TEXAS...
  TRINITY COUNTY IN SOUTHEASTERN TEXAS...
  CENTRAL HOUSTON COUNTY IN SOUTHEASTERN TEXAS...
  COLORADO COUNTY IN SOUTHEASTERN TEXAS...
  LIBERTY COUNTY IN SOUTHEASTERN TEXAS...
  SAN JACINTO COUNTY IN SOUTHEASTERN TEXAS...
  MONTGOMERY COUNTY IN SOUTHEASTERN TEXAS...
  SOUTHEASTERN BRAZOS COUNTY IN SOUTHEASTERN TEXAS...
  POLK COUNTY IN SOUTHEASTERN TEXAS...
  EASTERN MADISON COUNTY IN SOUTHEASTERN TEXAS...
  AUSTIN COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 100 PM CDT

* AT 853 AM CDT...DOPPLER RADAR AND AUTOMATED RAIN GAUGES INDICATED
  THUNDERSTORMS PRODUCING HEAVY RAIN ACROSS THE WARNED AREA.
  WIDESPREAD 4 TO 12 INCHES OF RAIN HAVE FALLEN ACROSS THE WARNED
  AREA. FLASH FLOODING IS ONGOING ACROSS A LARGE PORTION OF
  SOUTHEAST TEXAS.

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  PASADENA...PEARLAND...LEAGUE CITY...SUGAR LAND...BAYTOWN...MISSOURI
  CITY...CONROE...GALVESTON ISLAND WEST END...GALVESTON CAUSEWAY...TEXAS
  CITY...HUNTSVILLE...FRIENDSWOOD...LA PORTE...DEER PARK...ROSENBERG...
  ALVIN...NORTHERN ANGLETON...DICKINSON...STAFFORD AND SOUTH HOUSTON.

ADDITIONAL RAINFALL AMOUNTS OF 2 TO 4 INCHES OF RAIN ARE POSSIBLE IN
THE WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES. STAY OFF AREA ROADS.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES AS
WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...FARMLAND...AND OTHER LOW LYING
SPOTS.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNED AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY.

&&

LAT...LON 2947 9436 2913 9504 2929 9661 2933 9656
      2963 9687 2996 9657 3015 9665 3015 9672
      3046 9613 3109 9580 3137 9527 3113 9485
      3063 9457 3049 9454 3049 9473 3011 9460
      3011 9444 2956 9435

$$
39

1 follow-up statement

878 
WGUS74 KHGX 181548
FFSHGX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1048 AM CDT MON APR 18 2016

TXC015-039-041-071-089-157-167-185-201-225-291-313-339-373-407-455-
471-473-477-481-181800-
/O.CON.KHGX.FF.W.0021.000000T0000Z-160418T1800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WHARTON TX-WASHINGTON TX-HARRIS TX-WALKER TX-WALLER TX-GALVESTON TX-
CHAMBERS TX-GRIMES TX-BRAZORIA TX-FORT BEND TX-TRINITY TX-HOUSTON TX-
COLORADO TX-LIBERTY TX-SAN JACINTO TX-MONTGOMERY TX-BRAZOS TX-
POLK TX-MADISON TX-AUSTIN TX-
1048 AM CDT MON APR 18 2016

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 100 PM CDT FOR
CENTRAL WHARTON...WASHINGTON...HARRIS...WALKER...WALLER...
GALVESTON...CHAMBERS...GRIMES...NORTHERN BRAZORIA...FORT BEND...
TRINITY...CENTRAL HOUSTON...COLORADO...LIBERTY...SAN JACINTO...
MONTGOMERY...SOUTHEASTERN BRAZOS...POLK...EASTERN MADISON AND AUSTIN
COUNTIES...

AT 1041 AM CDT...DOPPLER RADAR AND AUTOMATED RAIN GAUGES INDICATED
THUNDERSTORMS PRODUCING HEAVY RAIN OVER THE WARNED AREA. WIDESPREAD
4 TO 12 INCHES OF RAIN HAVE ALREADY FALLEN ACROSS THE WARNED AREA.
FLASH FLOODING IS ONGOING ACROSS A LARGE PORTION OF SOUTHEAST TEXAS
AND MULTIPLE REPORTS OF STREET FLOODING HAVE BEEN RECEIVED FROM
AROUND THE WARNED AREA.

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
PASADENA...PEARLAND...LEAGUE CITY...SUGAR LAND...BAYTOWN...MISSOURI CITY...
CONROE...GALVESTON ISLAND WEST END...GALVESTON CAUSEWAY...TEXAS CITY...
HUNTSVILLE...FRIENDSWOOD...LA PORTE...DEER PARK...ROSENBERG...ALVIN...
NORTHERN ANGLETON...DICKINSON...STAFFORD AND SOUTH HOUSTON.

RAIN RATES ARE DECREASING IN THE WARNED AREA, BUT ADDITIONAL
RAINFALL AMOUNTS OF 2 TO 4 INCHES ARE POSSIBLE IN THE WARNED AREA
THROUGH THE AFTERNOON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES AS
WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNED AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY.

&&

LAT...LON 2947 9436 2913 9504 2929 9661 2933 9656
      2963 9687 2996 9657 3015 9665 3015 9672
      3046 9613 3109 9580 3137 9527 3113 9485
      3063 9457 3049 9454 3049 9473 3011 9460
      3011 9444 2956 9435

$$

HUFFMAN

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 17, 7:30 PM CDT	Special Weather Statement	HGX	Colorado	45 min
Apr 17, 8:10 PM CDT	Special Weather Statement	HGX	Colorado	65 min
Apr 17, 8:33 PM CDT	Special Weather Statement	HGX	Fort Bend, Waller	57 min
Apr 17, 8:53 PM CDT	Areal Flood Advisory	HGX	Colorado, Wharton	3 hr
Apr 17, 9:28 PM CDT	Areal Flood Advisory	HGX	Austin, Fort Bend, Harris, Waller	2 hr
Apr 17, 9:38 PM CDT	Flash Flood Warning	HGX	Fort Bend, Harris, Waller	112 min
Apr 17, 10:36 PM CDT	Flash Flood Warning	HGX	Austin, Colorado, Harris, Waller	3 hr
Apr 17, 11:11 PM CDT	River Flood Warning	HGX	Harris, Waller	7 days
Apr 17, 11:15 PM CDT	Special Weather Statement	HGX	Harris	45 min
Apr 17, 11:17 PM CDT	Special Weather Statement	HGX	Waller	43 min
Apr 17, 11:22 PM CDT	Flash Flood Warning	HGX	Grimes, Harris, Montgomery, Waller	3 hr
Apr 17, 11:29 PM CDT	Severe Thunderstorm Warning	HGX	Harris, Montgomery	31 min
Apr 17, 11:57 PM CDT	Severe Thunderstorm Warning	HGX	Harris, Montgomery	63 min
Apr 18, 12:04 AM CDT	Flash Flood Warning	HGX	Austin, Fort Bend, Harris, Montgomery, Waller	3 hr
Apr 18, 12:07 AM CDT	Tornado Warning	HGX	Harris, Montgomery	38 min
Apr 18, 12:39 AM CDT	River Flood Warning	HGX	Harris	45 hr
Apr 18, 12:48 AM CDT	River Flood Warning	HGX	Harris	45 hr
Apr 18, 1:04 AM CDT	River Flood Warning	HGX	Harris	69 hr
Apr 18, 1:15 AM CDT	Flash Flood Warning	HGX	Harris, Montgomery	3 hr
Apr 18, 1:23 AM CDT	Hydrologic Statement	HGX	Harris	6 days
Apr 18, 1:37 AM CDT	Flash Flood Warning	HGX	Austin, Colorado, Waller, Washington	3 hr
Apr 18, 1:44 AM CDT	Flash Flood Warning Emergency	HGX	Grimes, Harris, Waller	3 hr
Apr 18, 1:47 AM CDT	Flash Flood Warning	HGX	Grimes, Montgomery, San Jacinto, Walker	3 hr
Apr 18, 2:04 AM CDT	Flash Flood Warning Emergency	HGX	Harris	3 hr
Apr 18, 2:09 AM CDT	River Flood Warning	HGX	Harris, Montgomery	44 hr
Apr 18, 2:09 AM CDT	River Flood Warning	HGX	Harris, Montgomery	4 days
Apr 18, 2:09 AM CDT	Hydrologic Statement	HGX	Harris, Montgomery	6 days
Apr 18, 2:09 AM CDT	Hydrologic Statement	HGX	Harris	6 days
Apr 18, 2:09 AM CDT	Hydrologic Statement	HGX	Harris	6 days
Apr 18, 2:31 AM CDT	Flash Flood Warning	HGX	Grimes, Harris, Montgomery, Waller	2 hr
Apr 18, 3:03 AM CDT	Severe Thunderstorm Warning	HGX	Harris	27 min
Apr 18, 3:13 AM CDT	Tornado Warning	HGX	Harris	32 min
Apr 18, 3:14 AM CDT	River Flood Warning	HGX	Fort Bend, Harris	6 days
Apr 18, 3:14 AM CDT	River Flood Warning	HGX	Harris	6 days
Apr 18, 3:14 AM CDT	River Flood Warning	HGX	Harris	6 days
Apr 18, 3:14 AM CDT	River Flood Warning	HGX	Harris	6 days
Apr 18, 3:14 AM CDT	River Flood Warning	HGX	Harris	4 days
Apr 18, 3:14 AM CDT	River Flood Warning	HGX	Harris, Montgomery	4 days
Apr 18, 3:22 AM CDT	River Flood Warning	HGX	Colorado, Wharton	3 days
Apr 18, 3:23 AM CDT	Flash Flood Warning	HGX	Fort Bend, Harris, Waller	97 min
Apr 18, 3:28 AM CDT	Flash Flood Warning	HGX	Austin, Colorado	92 min
Apr 18, 3:38 AM CDT	Tornado Warning	HGX	Harris	27 min
Apr 18, 3:55 AM CDT	River Flood Warning	HGX	Harris	42 hr
Apr 18, 3:55 AM CDT	River Flood Warning	HGX	Harris	6 days
Apr 18, 3:55 AM CDT	River Flood Warning	HGX	Harris	6 days
Apr 18, 3:55 AM CDT	River Flood Warning	HGX	Harris	12 hr
Apr 18, 3:55 AM CDT	River Flood Warning	HGX	Harris	40 hr
Apr 18, 3:55 AM CDT	River Flood Warning	HGX	Harris	34 hr
Apr 18, 4:39 AM CDT	Flash Flood Warning Emergency	HGX	Austin, Colorado, Grimes, Harris, Montgomery, Waller	4 hr
Apr 18, 4:39 AM CDT	Flash Flood Warning	HGX	Austin, Colorado, Fort Bend, Grimes, Harris, Liberty and 7 more	4 hr
Apr 18, 4:51 AM CDT	River Flood Warning	HGX	Harris	41 hr
Apr 18, 4:51 AM CDT	River Flood Warning	HGX	Harris	41 hr
Apr 18, 4:51 AM CDT	River Flood Warning	HGX	Harris	41 hr
Apr 18, 4:52 AM CDT	Tornado Warning	HGX	Harris	23 min
Apr 18, 5:16 AM CDT	Coastal Flood Advisory	HGX	Brazoria, Matagorda	20 hr
Apr 18, 5:17 AM CDT	Severe Thunderstorm Warning	HGX	Chambers, Harris, Liberty	43 min
Apr 18, 5:39 AM CDT	Tornado Warning	HGX	Liberty	36 min
Apr 18, 5:57 AM CDT	Flash Flood Warning Emergency	HGX	Harris, Montgomery	3 hr
Apr 18, 5:59 AM CDT	River Flood Warning	HGX	Harris	40 hr
Apr 18, 5:59 AM CDT	River Flood Warning	HGX	Harris	40 hr
Apr 18, 5:59 AM CDT	River Flood Warning	HGX	Harris	40 hr
Apr 18, 5:59 AM CDT	River Flood Warning	HGX	Harris	26 hr
Apr 18, 6:12 AM CDT	River Flood Warning	HGX	Fort Bend, Harris	10 days
Apr 18, 6:12 AM CDT	River Flood Warning	HGX	Harris	10 days
Apr 18, 6:12 AM CDT	River Flood Warning	HGX	Harris	10 days
Apr 18, 6:12 AM CDT	River Flood Warning	HGX	Harris	10 days
Apr 18, 6:25 AM CDT	River Flood Warning	HGX	Harris	40 hr
Apr 18, 6:25 AM CDT	River Flood Warning	HGX	Harris	40 hr
Apr 18, 6:25 AM CDT	River Flood Warning	HGX	Harris	28 hr
Apr 18, 6:25 AM CDT	River Flood Warning	HGX	Harris	31 hr
Apr 18, 6:25 AM CDT	River Flood Warning	HGX	Harris	28 hr
Apr 18, 6:30 AM CDT	Flash Flood Warning Emergency	HGX	Austin, Colorado, Fort Bend, Harris, Waller	3 hr
Apr 18, 6:42 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 6:42 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 6:42 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 6:42 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 6:42 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 6:42 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 6:51 AM CDT	River Flood Warning	HGX	Harris	39 hr
Apr 18, 7:05 AM CDT	Flash Flood Warning Emergency	HGX	Fort Bend, Harris	115 min

Nearby

Flash Flood Warnings in Texas, 2016 Every flash flood warning in 2016

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.