Storm Surge and Flash Flooding in Texas, September 21 to 23, 2020

Name: Storm Surge and Flash Flooding in Texas, September 21 to 23, 2020
Start: 2020-09-21T00:00
End: 2020-09-23T23:59
Location: Texas

September 21 to 23, 2020 · NWS HGX · 14 events in 8 counties and zones

Where it happened

Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $950,000
Crop damage: None recorded
Events: 14

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS HGX wrote it up.

Tropical Storm Beta made landfall near Matagorda bay on September 21. As the system pushed slowly inland, portions of SE Texas experienced flash flooding from heavy rain bands, storm surge, and some strong wind gusts. Storm surge was enhanced by long fetch of northeast winds over Gulf behind a cold front. 20 to 25 homes were damaged from high water along portions of Clear Creek and Lower Brays Bayous.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Sep 20, 11:15 PM CST, 45 minutes earlier.

Area forecast discussion, Sep 20, 11:15 PM CST, 45 minutes before

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In the hours before

Local storm report, Sep 20, 9:57 PM CST, 2 hours 3 minutes before

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Local storm report, Sep 20, 11:04 PM CST, 56 minutes before

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Local storm report, Sep 20, 11:28 PM CST, 32 minutes before

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The radar

The Houston radar (KHGX), 32 km away, was scanning. The volume nearest the first event began at 00:50 UTC.

Open the radar archive at this moment

Event by event

6 flash flood, 5 storm surge/tide, 2 flood, 1 astronomical low tide. Local standard time, as filed.

Storm Surge/Tide, Galveston Island and Bolivar Peninsula

When: September 21, 12:00 AM CST to September 23, 11:59 PM CST
Where: Galveston Island and Bolivar Peninsula forecast zone
Reported by: Emergency Manager
Coordinates: 29.298, -94.811 (the zone’s center; the record gives no point)

Significant beach erosion occurred along the Bolivar Peninsula and Galveston Island. A fishing pier at 61st St. in Galveston was damaged. Numerous roads were flooded from high storm tides. Some garages were inundated with water. Maximum water heights reached 3.77 ft above MHHW at the Galveston Fishing Pier and 3.56 above MHHW at the Galveston Bay entrance.

Storm Surge/Tide, Coastal Galveston

When: September 21, 12:00 AM CST to September 23, 11:59 PM CST
Where: Coastal Galveston forecast zone
Reported by: Emergency Manager
Coordinates: 29.298, -94.811 (the zone’s center; the record gives no point)

Widespread coastal flooding occurred across coastal Galveston County. Flooding was observed in San Leon, Bayou Vista, Clear Lake Shores, and Kemah. The Kemah Boardwalk was flooded. Numerous instances of street flooding and road closures were reported. Heavy rain from the storm resulted in bayou and creek flooding, including Clear Creek.

Storm Surge/Tide, Coastal Harris

When: September 21, 12:00 AM CST to September 23, 11:59 PM CST
Where: Coastal Harris forecast zone
Reported by: Emergency Manager
Coordinates: 29.857, -95.392 (the zone’s center; the record gives no point)

Several roads were impassable in Seabrook due to storm surge flooding, including Todville Rd, Hammer St, Main St, and 10th St. A fishing pier and kayak launch were damaged in Shoreacres. At Manchester, a maximum water level of 4.58 ft above MHHW was observed.

Storm Surge/Tide, Coastal Matagorda

When: September 21, 12:00 AM CST to September 23, 11:59 PM CST
Where: Coastal Matagorda forecast zone
Reported by: Emergency Manager
Coordinates: 28.786, -96.004 (the zone’s center; the record gives no point)

Several roads were impassable due to storm surge flooding in the Sargent area. In Matagorda, a maximum water level of 3.56 ft above MHHW was observed.

Astronomical Low Tide, Matagorda Islands

When: September 21, 12:00 AM CST to September 23, 11:59 PM CST
Where: Matagorda Islands forecast zone
Reported by: Emergency Manager
Coordinates: 28.786, -96.004 (the zone’s center; the record gives no point)

Roads were impassable due to storm surge flooding near Matagorda Beach. Beach erosion occurred along Matagorda Beach.

Storm Surge/Tide, Brazoria Islands

When: September 21, 12:00 AM CST to September 23, 11:59 PM CST
Where: Brazoria Islands forecast zone
Reported by: Emergency Manager
Coordinates: 29.168, -95.434 (the zone’s center; the record gives no point)

Road washout occurred along the Bluewater Highway. Significant beach erosion was observed. A water level of 4.15 ft above MHHW was observed at San Luis Pass.

Flash Flood, Harris

When: September 21, 6:50 PM CST to September 22, 6:50 AM CST
Where: Harris County, 8.05 mi ENE of Friendswood to 8.5 mi ENE of Friendswood
Cause: Heavy Rain
Property damage: $50,000
Reported by: Law Enforcement
Coordinates: 29.558, -95.290

High water, road impassable, Walnut Street between Veterans and Main.

Flash Flood, Harris

When: September 21, 7:14 PM CST to 10:00 PM CST
Where: Harris County, 1.75 mi SSW of East Haven to 0.22 mi N of Pearland
Cause: Heavy Rain
Property damage: $100,000
Reported by: Law Enforcement
Coordinates: 29.605, -95.278

Cars submerged, high water rescues near Sam Houston Parkway and Telephone Road.

Flood, Harris

When: September 21, 8:00 PM CST to September 22, 8:00 PM CST
Where: Harris County, 1.87 mi SSE of Minnetex to 2.02 mi ESE of Houston Clover Arpt
Cause: Heavy Rain
Property damage: $500,000
Reported by: Emergency Manager
Coordinates: 29.596, -95.356

Clear Creek flooded out of its banks from 288 to Clear Lake. Water in homes, low lying areas, near Pearland, Friendswood. Also few homes flooded near 610 loop and Cullen. Total of 20 to 25 homes total.

Flash Flood, Harris

When: September 21, 8:30 PM CST to 10:30 PM CST
Where: Harris County, 1.2 mi W of West Park to 0.54 mi SW of West Park
Cause: Heavy Rain
Property damage: $100,000
Reported by: Law Enforcement
Coordinates: 29.680, -95.590

Roads flooded, closed between Synott Rd, S Kirkwood, West Belford and Bissonet.

Flash Flood, Harris

When: September 21, 9:40 PM CST to 11:40 PM CST
Where: Harris County, 1.83 mi SE of Mykawa to 1.48 mi NNW of Cloverleaf
Cause: Heavy Rain
Property damage: $100,000
Reported by: Law Enforcement
Coordinates: 29.600, -95.300

Numerous streets flooded, closed around Brookside Village.

Flash Flood, Harris

When: September 21, 9:40 PM CST to 11:40 PM CST
Where: Harris County, 0.69 mi S of Jeannetta to 0.86 mi NE of Stafford
Cause: Heavy Rain
Property damage: $100,000
Reported by: Law Enforcement
Coordinates: 29.670, -95.530

Numerous roads flooded, closed from south of Bellaire to around Meadow's Place.

Flash Flood, Jackson

When: September 22, 3:00 AM CST to 4:00 AM CST
Where: Jackson County, 0.3 mi NNW of Matilda to 1.09 mi NW of Edna
Cause: Heavy Rain
Reported by: Department of Highways
Coordinates: 28.974, -96.682

US 59 Frontage roads in the Edna area were flooded.

Flood, Harris

When: September 22, 4:00 AM CST to 9:00 AM CST
Where: Harris County, 1.63 mi NE of Pierce Jct to 0.72 mi NE of Pierce Jct
Cause: Heavy Rain
Reported by: Law Enforcement
Coordinates: 29.689, -95.384

Route 288 at 610 closed in both directions due to flooding.

What these are

Storm Surge/Tide: Water pushed ashore above the normal tide by a storm’s winds and low pressure.
Astronomical Low Tide: Unusually low water from tides and offshore wind that caused impacts.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Texas in 2020 Every state in 2020 This day in weather history Warnings in Texas, September 2020 The 2020 hurricane season

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-30. Each event’s entry at NCEI: 920223, 920224, 920225, 920226, 920227, 920228, 921898, 921900, 922065, 922014, 922027, 922029, 920229, 922055.