Louisiana, 2020

Flash Flood in Louisiana, September 23, 2020

September 23, 2020 · NWS SHV · 1 event in 1 county or zone

Post-Tropical Cyclone Beta moved ashore across portions of extreme Southeast Texas during the morning hours of September 23rd, with deep tropical moisture associated with this system continuing to spread northeast across much of Louisiana from the 21st to the 23rd. 50 to 3 inches falling over this area as the remnants of Beta tracked northeast across Central Louisiana and Western Mississippi.

Where it happened

Every event with a place to put it. 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

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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
1

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 SHV wrote it up.

Post-Tropical Cyclone Beta moved ashore across portions of extreme Southeast Texas during the morning hours of September 23rd, with deep tropical moisture associated with this system continuing to spread northeast across much of Louisiana from the 21st to the 23rd. Periods of showers and embedded thunderstorms developed and spread across North Louisiana from the 21st through the 22nd ahead of Beta, resulting in widespread rainfall amounts of 1.50 to in excess of 3 inches, with additional rainfall amounts of 1.50 to 3 inches falling over this area as the remnants of Beta tracked northeast across Central Louisiana and Western Mississippi. Given the saturated grounds due to rains over the prior few days, localized flooding was observed in Sterlington in Northern Ouachita Parish.

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 Shreveport, LA wrote its last area forecast discussion before the first event at Sep 23, 11:41 AM CST, 52 minutes earlier.

Area forecast discussion, Sep 23, 11:41 AM CST, 52 minutes before
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Hazardous weather outlook, Sep 23, 12:04 PM CST, 29 minutes before
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The radar

The Shreveport radar (KSHV), 166 km away, was scanning. The volume nearest the first event began at 18:33 UTC.

Open the radar archive at this moment

Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, Ouachita

When
September 23, 12:33 PM CST to 1:45 PM CST
Where
Ouachita County, 0.97 mi SSW of Sterlington to 0.4 mi S of Sterlington
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
32.688, -92.088

Street flooding was reported throughout the city of Sterlington.

What these are

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.

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

The same day elsewhere

More

Every storm in Louisiana in 2020Every state in 2020This day in weather historyWarnings in Louisiana, September 2020

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 2026-09-24. Each event’s entry at NCEI: 913737.