Alert archive / Texas / Flash Flood Warnings in 2021
Flash Flood Warning 35, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this flash flood warning at Sep 14, 2021, 3:33 AM CDT for 4 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
- Sep 14, 2021, 3:33 AM CDT (08:33 UTC)
- Expired
- Sep 14, 2021, 7:30 AM CDT
- In force
- 4 hr
- Issued by
- NWS Houston/Galveston, TX
- Area
- Storm-based polygon
- Flood severity
- None
Counties Brazoria County, TX, Chambers County, TX, Galveston County, TX, Harris County, TX
The radar
The Houston radar (KHGX), 16 km from the middle of the area, began a volume at 08:36 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 |
|---|---|---|---|
| Sep 14, 7:15 AM CDT | FLASH FLOOD | 2 Nw Pasadena, TX | SH 225 FEEDER ROAD CLOSED AT RICHEY ST DUE TO FLOODING. |
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 00:00Z, 8.6 hours before the alert went out and 199 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.
- Mixed-layer CAPE
- 528 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 794 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 53 m²/s²
- 0-3 km storm-relative helicity
- 327 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 2.3
The text
As transmitted.
161
WGUS54 KHGX 140833
FFWHGX
TXC039-071-167-201-141230-
/O.NEW.KHGX.FF.W.0035.210914T0833Z-210914T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Houston/Galveston TX
333 AM CDT Tue Sep 14 2021
The National Weather Service in League City has issued a
* Flash Flood Warning for...
North Central Brazoria County in southeastern Texas...
West Central Chambers County in southeastern Texas...
Northwestern Galveston County in southeastern Texas...
Harris County in southeastern Texas...
* Until 730 AM CDT.
* At 333 AM CDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Pasadena, Pearland, northern League City, Baytown, Friendswood, La
Porte, Deer Park, Alvin, South Houston, Seabrook, Galena Park,
Manvel, Beach City, Kemah, South Belt / Ellington, Clear Lake,
Greater Hobby Area, Cloverleaf, Channelview and Highlands.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 2971 9524 2981 9518 2982 9508 2981 9479
2966 9488 2965 9492 2970 9496 2967 9498
2960 9497 2953 9499 2957 9512 2938 9536
2928 9544 2939 9550 2944 9548 2944 9546
2949 9545
FLASH FLOOD...RADAR INDICATED
$$The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 13, 7:32 PM CDT | Flash Flood Warning | HGX | Brazoria, Jackson, Matagorda | 3 hr |
| Sep 13, 9:46 PM CDT | Flash Flood Warning | HGX | Brazoria, Galveston, Matagorda | 4 hr |
| Sep 13, 10:06 PM CDT | Hurricane Warning | HGX | Brazoria, Jackson, Matagorda | 6 hr |
| Sep 13, 10:31 PM CDT | Flash Flood Warning | HGX | Matagorda | 3 hr |
| Sep 14, 1:43 AM CDT | Flash Flood Warning | HGX | Brazoria, Galveston, Harris, Matagorda | 4 hr |
| Sep 14, 3:57 AM CDT | Small Craft Advisory | HGX | 18 hr | |
| Sep 14, 4:04 AM CDT | Coastal Flood Advisory | HGX | Brazoria, Chambers, Galveston, Harris, Matagorda | 14 hr |
| Sep 14, 4:42 AM CDT | River Flood Warning | HGX | Galveston, Harris | 28 hr |
| Sep 14, 5:29 AM CDT | River Flood Warning | HGX | Galveston, Harris | 21 days |
| Sep 14, 5:31 AM CDT | River Flood Warning | HGX | Galveston, Harris | 21 days |
| Sep 14, 5:45 AM CDT | Flash Flood Warning | HGX | Brazoria, Chambers, Galveston, Harris | 3 hr |
| Sep 14, 8:11 AM CDT | Areal Flood Warning | HGX | Brazoria, Galveston, Harris | 3 hr |
Nearby
Flash Flood Warnings in Texas, 2021Every flash flood warning in 2021
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.