Alert archive / Texas / Flash Flood Warnings in 2020
Flash Flood Warning 6, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this flash flood warning at May 15, 2020, 4:25 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
- May 15, 2020, 4:25 PM CDT (21:25 UTC)
- Expired
- May 15, 2020, 6:30 PM 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 21:30 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, 9.4 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.
- Mixed-layer CAPE
- 1341 J/kg
- Mixed-layer CIN
- -15 J/kg
- Mixed-layer LCL
- 509 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 64 m²/s²
- 0-3 km storm-relative helicity
- 118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.9
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 15, 4:25 PM CDT, 0 minutes earlier.
Area forecast discussion, May 15, 4:25 PM CDT, 0 minutes before
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Special weather statement, May 15, 1:12 PM CDT, 3 hours 13 minutes before
Special Weather Statement National Weather Service Houston/Galveston TX 112 PM CDT Fri May 15 2020 TXZ199-200-213-313-151900- Northern Liberty TX-Coastal Harris TX-Inland Harris TX-Montgomery TX- 112 PM CDT Fri May 15 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN MONTGOMERY... SOUTHWESTERN LIBERTY AND NORTHEASTERN HARRIS COUNTIES UNTIL 200 PM CDT... At 111 PM CDT, Doppler radar was tracking a strong thunderstorm 8 miles west of Dayton, moving southwest at 10 mph. Pea size hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Humble, Kingwood, Crosby, Lake Houston Dam, Lake Houston, Atascocita and Sheldon. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 3014 9501 3007 9493 2985 9513 3005 9531 TIME...MOT...LOC 1811Z 056DEG 10KT 3007 9504
Special weather statement, May 15, 2:23 PM CDT, 2 hours 2 minutes before
Special Weather Statement National Weather Service Houston/Galveston TX 223 PM CDT Fri May 15 2020 TXZ227-237-152000- Inland Brazoria TX-Fort Bend TX- 223 PM CDT Fri May 15 2020 ...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL FORT BEND AND NORTH CENTRAL BRAZORIA COUNTIES UNTIL 300 PM CDT... At 221 PM CDT, Doppler radar was tracking a strong thunderstorm over Arcola, or near Fresno, moving northwest at 5 mph. Pea size hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Southwestern Pearland, southeastern Missouri City, western Manvel, Fresno, Arcola, Iowa Colony, Sienna Plantation and Juliff. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 2958 9539 2941 9534 2942 9547 2952 9555 TIME...MOT...LOC 1921Z 137DEG 6KT 2949 9544
Special weather statement, May 15, 2:47 PM CDT, 1 hour 38 minutes before
Special Weather Statement National Weather Service Houston/Galveston TX 247 PM CDT Fri May 15 2020 TXZ199-213-152030- Inland Harris TX-Montgomery TX- 247 PM CDT Fri May 15 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN MONTGOMERY AND NORTH CENTRAL HARRIS COUNTIES UNTIL 330 PM CDT... At 246 PM CDT, Doppler radar was tracking a strong thunderstorm over Tomball, moving north at 15 mph. Winds in excess of 40 mph will be possible with this storm. Locations impacted include... Tomball, Pinehurst, The Woodlands, Magnolia, Stagecoach and Hooks Airport. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3006 9548 3003 9567 3026 9580 3031 9554 TIME...MOT...LOC 1946Z 165DEG 15KT 3009 9560 TJC
Local storm report, May 15, 2:57 PM CDT, 1 hour 28 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
257 PM CDT FRI MAY 15 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0246 PM MARINE TSTM WIND 2 ESE SHOREACRES 29.61N 94.98W
05/15/2020 E41 MPH GMZ335 TX MESONET
36 KNOT WIND GUST VIA WEATHER FLOW.
&&Special weather statement, May 15, 3:20 PM CDT, 1 hour 5 minutes before
Special Weather Statement National Weather Service Houston/Galveston TX 320 PM CDT Fri May 15 2020 TXZ213-237-238-313-337-338-152100- Inland Brazoria TX-Coastal Harris TX-Inland Galveston TX- Coastal Galveston TX-Inland Harris TX-Coastal Brazoria TX- 320 PM CDT Fri May 15 2020 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN GALVESTON... NORTHEASTERN BRAZORIA AND SOUTHERN HARRIS COUNTIES UNTIL 400 PM CDT... At 319 PM CDT, Doppler radar was tracking a strong thunderstorm over southeastern League City, moving southwest at 20 mph. Wind gusts of 50 to 55 mph will be possible with this storm. Locations impacted include... Southern Pasadena, League City, Texas City, Friendswood, Alvin, Dickinson, La Marque, Santa Fe, Webster, Hitchcock, southeastern Manvel, Kemah, southern Clear Lake, Nassau Bay, Taylor Lake Village, El Lago, Clear Lake Shores, Hillcrest, The Johnson Space Center and Bacliff. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 2960 9509 2946 9495 2927 9516 2944 9535 TIME...MOT...LOC 2019Z 048DEG 16KT 2949 9509 TJC
Local storm report, May 15, 3:48 PM CDT, 37 minutes before
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</html>The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 14, 7:21 PM CDT | Special Weather Statement | HGX | Madison | 24 min |
| May 15, 5:14 AM CDT | Flash Flood Watch | HGX | Austin, Brazoria, Chambers, Colorado, Fort Bend, Galveston and 9 more | 26 hr |
| May 15, 1:03 PM CDT | Special Weather Statement | HGX | Harris | 42 min |
| May 15, 1:07 PM CDT | Special Marine Warning | HGX | 38 min | |
| May 15, 1:12 PM CDT | Special Weather Statement | HGX | Harris | 48 min |
| May 15, 2:15 PM CDT | Areal Flood Advisory | HGX | Brazoria, Fort Bend, Harris | 3 hr |
| May 15, 2:23 PM CDT | Special Weather Statement | HGX | Fort Bend | 37 min |
| May 15, 2:34 PM CDT | Areal Flood Advisory | HGX | Harris | 116 min |
| May 15, 2:40 PM CDT | Special Marine Warning | HGX | 65 min | |
| May 15, 2:47 PM CDT | Special Weather Statement | HGX | Montgomery | 43 min |
| May 15, 3:03 PM CDT | Areal Flood Advisory | HGX | Galveston, Harris | 117 min |
| May 15, 3:05 PM CDT | Areal Flood Advisory | HGX | Fort Bend, Harris | 3 hr |
| May 15, 3:17 PM CDT | Flash Flood Warning | HGX | Harris | 118 min |
| May 15, 3:20 PM CDT | Special Weather Statement | HGX | Galveston | 40 min |
| May 15, 3:42 PM CDT | Flash Flood Warning | HGX | Galveston, Harris | 4 hr |
| May 15, 4:59 PM CDT | Special Weather Statement | HGX | Galveston | 46 min |
| May 15, 5:19 PM CDT | Areal Flood Advisory | HGX | Harris | 56 min |
| May 15, 6:01 PM CDT | Special Weather Statement | HGX | Brazoria, Galveston | 59 min |
| May 15, 6:03 PM CDT | Special Marine Warning | HGX | 57 min |
Nearby
Flash Flood Warnings in Texas, 2020Every flash flood warning in 2020
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.