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Grand Isle, LA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Grand Isle, a town in Jefferson County, Louisiana.

Overnight
81°F
Mostly Clear
Mostly clear. Low around 81, with temperatures rising to around 83 overnight. Southeast wind 0 to 5 mph.

7-day forecast for Grand Isle

WhenTempForecastWindPrecip
Overnight 81°F Mostly Clear 0 to 5 mph SE 1%
Sunday 87°F Sunny 0 to 10 mph E 4%
Sunday Night 81°F Mostly Clear 0 to 5 mph SW 2%
Monday 88°F Slight Chance Showers And Thunderstorms 5 to 10 mph NE 23%
Monday Night 81°F Mostly Clear 0 to 5 mph E 14%
Tuesday 88°F Sunny 5 to 10 mph NE 13%
Tuesday Night 81°F Mostly Clear 0 to 10 mph E 12%
Wednesday 88°F Sunny 5 to 15 mph NE 12%
Wednesday Night 81°F Mostly Clear 5 to 10 mph E 12%
Thursday 87°F Sunny 15 mph NE 7%
Thursday Night 80°F Mostly Clear 10 to 15 mph E 7%
Friday 87°F Mostly Sunny 15 mph E 8%
Friday Night 80°F Partly Cloudy 5 to 10 mph E 8%
Saturday 86°F Mostly Sunny 10 to 15 mph E 8%

Forecast source: National Weather Service (api.weather.gov) for Grand Isle (29.213, -90.029). Updated through the day.

Growing snapshot for Grand Isle

Last spring frost
Feb 8
First fall frost
Dec 19
Growing season
311 days
Hardiness zone
10a

More local growing data for Grand Isle: nearby ZIP 70358 weather · frost dates · planting calendar · Louisiana frost dates

Nearby towns & communities

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Climate data from the nearest NOAA station, Galliano, La (24 mi from Grand Isle). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.