Heavy Rain Update - September 17th, 2021 7 AM

Click HERE for an update concerning what is now Post-Tropical Cyclone (remnant low) Nicholas and the heavy rain threat for tonight through the weekend.

Changes from the previous update:

• No major changes

Overview:

WHAT: SLIGHT to MARGINAL RISK of Heavy Rain today and tonight. A marginal risk for excessive rainfall for Saturday and Saturday night.

WHEN:  Today through Saturday night.

WHERE: Entire area

CONFIDENCE: 

• We are confident that additional bands of showers and thunderstorms will bring minor to moderate impacts in the form of locally heavy rainfall to portions of SE LA and coastal MS.

Impacts:

Rainfall/Flash Flooding:

• Additional rainfall of 1 to 3 inches is currently forecast with locally higher amounts possible through the weekend. The highest rain rates of 1 to 2 inches per hour.

• Expect ponding of water in low-lying areas and some localized flash flooding due to the very saturated grounds and high rainfall rates.

• Numerous rivers are in or going to minor to moderate flood stages, mainly along with the Northshore areas and Mississippi coastal areas

Flash Flood Watch in effect until 7 PM this evening:

• Rainfall amounts of 1 to 2 inches will be possible with locally higher amounts,

• Flash Flooding will be possible as well as and ongoing river flooding due to recent heavy rains and additional heavy rainfall through today.

• Flash Flood watch might be extended later today through Saturday.

The attached briefing highlights the threats associated with this system.

Additional Information and Resources:

NWS New Orleans Website: www.weather.gov/neworleans

NWS New Orleans DSS Website: https://www.weather.gov/lix/embrief

River Gauges and Forecasts: http://water.weather.gov/ahps2/index.php?wfo=lix

NWS New Orleans Facebook: www.facebook.com/NWSNewOrleans

NWS New Orleans Twitter: https://twitter.com/NWSNewOrleans

Online Weather Reporting: https://www.weather.gov/lix/submit_storm_report

Request for information: Please relay any reports of flash flooding to our office ASAP.  You can send reports via NWSChat or by phone.  If emailing pictures, please send them to <sr-lix.forecasters@noaa.gov>.