Tropical Storm Sally Update - 09/14/2020 5:00am

Changes from previous update: 

• Only a few changes to surge

Port Fourchon to the mouth of the MS River now 3 to 5 feet

Ocean Springs to MS/AL border now 5 to 8 feet

Overview:

Tropical Storm Sally is forecast to move generally west-northwestward through today and slow down as it approaches the mouth of the MS River, then slowly turn more northerly early Tuesday. Sally is forecast to intensify to a hurricane prior to landfall. Where Sally eventually slows and turns north will be a big factor in impacts for the region.

Confidence:

• There is normal confidence in the track and intensity forecast. The expected impacts could still change depending on track and intensity.

Impacts:

Storm Surge:

• A Storm Surge Warning is in effect from the Port Fourchon to the MS/AL border.
• Possible storm surge inundation levels:
  • The Mouth of the MS River to Ocean Springs: 7 to 11 feet
  • Ocean Springs to MS/AL Border: 5 to 8 feet
  • Lake Pontchartrain and Maurepas: 4 to 6 feet
  • Port Fourchon to the mouth of the MS River: 3 to 5 feet
  • Morgan City to Port Fourchon: 1 to 3 feet

• Expect low-lying, coastal roads to become impassable due to flooding

• Some areas may become cut off or inaccessible 

Rainfall/Flooding:

• Flash Flood Watch in effect tonight through Wednesday afternoon.

• Rainfall of 8 to 16 inches with locally higher amounts of over 24 inches possible

• Depending on where the heavy rain falls in relation to river drainage basins, river flooding could develop.

• Possible slow movement of this system could create significant rainfall and associated flooding threats

Wind and tornado:

• Sustained tropical storm force winds with higher gusts are forecast with hurricane force wind gusts possible. Parts of SE LA may see sustained hurricane force winds especially along the coast east of the MS River.

• These winds could result in minor damage mainly to trees, power lines, and weaker structures. 

• A few tornadoes will be possible in the storm’s rain bands. Tornadoes in these situations are typically short-lived, but they move very quickly.

Additional Information and Resources:

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

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

NWS New Orleans Tropical Page: https://www.weather.gov/srh/tropical?office=lix

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

National Hurricane Center Website: https://www.nhc.noaa.gov/

Next Update and Contact Information:

The next update will be sent around 11 am CDT