Alert archive / Texas / Flash Flood Warnings in 2021
Flash Flood Warning 40, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this flash flood warning at Oct 1, 2021, 9:19 AM CDT for Grimes County, Waller County, Washington 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 outline as issued.
The facts
- Issued
- Oct 1, 2021, 9:19 AM CDT (14:19 UTC)
- Expired
- Oct 1, 2021, 12:00 PM CDT
- In force
- 3 hr
- Issued by
- NWS Houston/Galveston, TX
- Area
- Storm-based polygon
- Flood severity
- None
Counties Grimes County, TX, Waller County, TX, Washington County, TX
The radar
The Houston radar (KHGX), 116 km from the middle of the area, began a volume at 14:22 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 12:00Z, 2.3 hours before the alert went out and 272 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
- 1808 J/kg
- Mixed-layer CIN
- -10 J/kg
- Mixed-layer LCL
- 585 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 57 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.2
The text
As transmitted.
022
WGUS54 KHGX 011419
FFWHGX
TXC185-473-477-011445-
/O.NEW.KHGX.FF.W.0040.211001T1419Z-211001T1445Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Houston/Galveston TX
919 AM CDT Fri Oct 1 2021
The National Weather Service in League City has issued a
* Flash Flood Warning for...
South Central Grimes County in southeastern Texas...
Northwestern Waller County in southeastern Texas...
Southeastern Washington County in southeastern Texas...
* Until 945 AM CDT.
* At 919 AM CDT, Local law enforcement reported water-covered roads,
at least one impassable, due to thunderstorms producing heavy
rain. Between 4 and 7 inches of rain have fallen. The expected
rainfall rate of continued rainfall is up to 1 to 2 inches in 1
hour. Flash flooding is ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Law enforcement reported.
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...
Hempstead, Prairie View and Pine Island.
This includes the following Low Water Crossings...
US 290 @ FM 1098, Farm to Market 362 at Beason Creek, Blinka Road at
Mound Creek, Brooks Road at Ponds Creek, Fields Store Road at Spring
Creek, Scroggins Lane at Three Mile Creek, Howell Road at Three Mile
Creek and Robinson Road at Three Mile Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3015 9621 3029 9607 3026 9595 3017 9589
3014 9589 3012 9590 3014 9593 3014 9594
3016 9596 3008 9593 2997 9603 2997 9607
3000 9609 3001 9608 3003 9609 3003 9611
3005 9611 3006 9614
FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR
$$2 follow-up statements
616
WGUS54 KHGX 011420
FFWHGX
TXC185-473-477-011700-
/O.EXT.KHGX.FF.W.0040.000000T0000Z-211001T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Houston/Galveston TX
920 AM CDT Fri Oct 1 2021
The National Weather Service in League City has extended the
* Flash Flood Warning for...
South Central Grimes County in southeastern Texas...
Northwestern Waller County in southeastern Texas...
Southeastern Washington County in southeastern Texas...
* Until noon CDT.
* At 920 AM CDT, local law enforcement reported thunderstorms
producing heavy rain in FM 1488 and Wyatt Chapel Rd. Between 4 and
7 inches of rain have fallen. The expected rainfall rate is 1 to 2
inches in 1 hour. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Law enforcement reported.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Hempstead, Prairie View and Pine Island.
This includes the following Low Water Crossings...
US 290 @ FM 1098, Farm to Market 362 at Beason Creek, Blinka Road at
Mound Creek, Brooks Road at Ponds Creek, Fields Store Road at Spring
Creek, Scroggins Lane at Three Mile Creek, Howell Road at Three Mile
Creek and Robinson Road at Three Mile Creek.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3015 9621 3029 9607 3026 9595 3017 9589
3014 9589 3012 9590 3014 9593 3014 9594
3016 9596 3008 9593 2997 9603 2997 9607
3000 9609 3001 9608 3003 9609 3003 9611
3005 9611 3006 9614
FLASH FLOOD...OBSERVED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR
$$832
WGUS74 KHGX 011702
FFSHGX
Flash Flood Statement
National Weather Service Houston/Galveston TX
1202 PM CDT Fri Oct 1 2021
TXC185-473-477-011712-
/O.EXP.KHGX.FF.W.0040.000000T0000Z-211001T1700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Grimes TX-Waller TX-Washington TX-
1202 PM CDT Fri Oct 1 2021
...FLASH FLOOD WARNING FOR SOUTH CENTRAL GRIMES, NORTHWESTERN WALLER
AND SOUTHEASTERN WASHINGTON COUNTIES IS REPLACED BY A FLOOD
WARNING...
The heavy rain has ended. Flooding is no longer expected to pose an
imminent threat. However, continued light to moderate rain will slow
or prevent current floodwaters from receding. Please continue to
heed remaining road closures.
LAT...LON 3015 9621 3029 9607 3026 9595 3017 9589
3014 9589 3012 9590 3014 9593 3014 9594
3016 9596 3008 9593 2997 9603 2997 9607
3000 9609 3001 9608 3003 9609 3003 9611
3005 9611 3006 9614
$$The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 1, 5:37 AM CDT | Areal Flood Advisory | HGX | Chambers, Harris, Liberty | 27 min |
| Oct 1, 5:57 AM CDT | Areal Flood Advisory | HGX | Austin, Grimes, Waller, Washington | 2 hr |
| Oct 1, 6:04 AM CDT | Flash Flood Warning | HGX | Harris | 3 hr |
| Oct 1, 6:52 AM CDT | Areal Flood Advisory | HGX | Harris | 113 min |
| Oct 1, 7:23 AM CDT | Areal Flood Advisory | HGX | Fort Bend, Harris, Waller | 67 min |
| Oct 1, 7:40 AM CDT | Areal Flood Advisory | HGX | Austin, Grimes, Harris, Waller, Washington | 99 min |
| Oct 1, 8:29 AM CDT | Flash Flood Warning | HGX | Fort Bend, Harris, Waller | 3 hr |
| Oct 1, 8:34 AM CDT | Areal Flood Advisory | HGX | Harris, Montgomery | 65 min |
| Oct 1, 8:38 AM CDT | Flash Flood Warning | HGX | Polk, San Jacinto, Trinity | 3 hr |
| Oct 1, 9:01 AM CDT | Areal Flood Warning | HGX | Chambers, Harris, Liberty | 5 hr |
| Oct 1, 9:25 AM CDT | Areal Flood Advisory | HGX | Fort Bend | 3 hr |
| Oct 1, 9:37 AM CDT | Areal Flood Advisory | HGX | Harris | 3 hr |
| Oct 1, 10:57 AM CDT | Areal Flood Warning | HGX | Fort Bend, Harris, Waller | 3 hr |
| Oct 1, 11:01 AM CDT | Areal Flood Advisory | HGX | Liberty, San Jacinto | 3 hr |
| Oct 1, 11:08 AM CDT | River Flood Warning | HGX | Harris | 4 hr |
| Oct 1, 11:54 AM CDT | Areal Flood Advisory | HGX | Polk, San Jacinto, Trinity | 2 hr |
| Oct 1, 12:02 PM CDT | Areal Flood Warning | HGX | Austin, Grimes, Harris, Waller, Washington | 2 hr |
| Oct 1, 12:42 PM CDT | Areal Flood Advisory | HGX | Fort Bend, Harris, Montgomery | 78 min |
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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.