National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Galliano, South Lafourche Airport (KGAO)

Lat: 29.44°NLon: 90.26°WElev: 0ft.

Overcast

93°F

34°C

Humidity 49%
Wind Speed Calm
Barometer 30.10 in
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Heat Index100°F (38°C)
Last update 17 Aug 1:35 pm CDT
Extended Forecast for

Grand Isle LA

Heat Advisory August 18, 11:00am until August 18, 08:00pm
Extreme Heat Warning August 17, 01:44pm until August 17, 08:00pm
Click here for hazard details and duration
Heat Advisory
Extreme Heat Warning
  •  
    Extreme Heat Warning August 17, 01:44pm until August 17, 08:00pm

    NOW until 8:00pm Mon

    Extreme Heat Warning

  • This Afternoon

    High: 89 °F

    Mostly Sunny

  • Tonight

    Tonight: Partly cloudy, with a steady temperature around 87. Southwest wind around 10 mph.

    Low: 87 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 90. Heat index values as high as 105. West wind 5 to 10 mph.

    High: 90 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 84. West wind around 10 mph.

    Low: 84 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 90. Southwest wind around 10 mph.

    High: 90 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 83. West wind around 10 mph.

    Low: 83 °F

    Partly Cloudy

  • Thursday

    Thursday: Sunny, with a high near 90. West wind 5 to 10 mph.

    High: 90 °F

    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 83. West wind 10 to 15 mph.

    Low: 83 °F

    Partly Cloudy

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 89. Southwest wind 5 to 10 mph.
Tonight
Partly cloudy, with a steady temperature around 87. Southwest wind around 10 mph.
Tuesday
Mostly sunny, with a high near 90. Heat index values as high as 105. West wind 5 to 10 mph.
Tuesday Night
Partly cloudy, with a low around 84. West wind around 10 mph.
Wednesday
Mostly sunny, with a high near 90. Southwest wind around 10 mph.
Wednesday Night
Partly cloudy, with a low around 83. West wind around 10 mph.
Thursday
Sunny, with a high near 90. West wind 5 to 10 mph.
Thursday Night
Partly cloudy, with a low around 83. West wind 10 to 15 mph.
Friday
A slight chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 90. West wind 5 to 10 mph.
Friday Night
Partly cloudy, with a low around 83. West wind around 10 mph.
Saturday
A chance of showers and thunderstorms. Mostly sunny, with a high near 90. West wind 5 to 10 mph.
Saturday Night
Partly cloudy, with a low around 83. West wind 5 to 10 mph.
Sunday
A chance of showers and thunderstorms. Sunny, with a high near 90. Northwest wind 5 to 10 mph.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Grand Isle LA
 29.23°N 89.99°W
Last Update:
1:25 pm CDT Aug 17, 2026
Forecast Valid:
1pm CDT Aug 17, 2026-6pm CDT Aug 23, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation