All Countries
Weather & Climate in Grand Isle, LA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Grand Isle enjoys a temperate climate with an average annual temperature of 69°F (21°C). Winters average 54°F in January while summers reach 82°F in July. The area gets 317 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Annual precipitation totals 66.7 inches (wetter than the 38-inch national average). Air quality is rated Good with a median AQI of 42. The city sits at an elevation of 2 feet.
Temperature
54°F Jan (12°C)
82°F Jul (28°C)
| Annual Average | 69.4°F |
| 29% above US avg | |
| January Average | 54°F (12°C) |
| July Average | 82°F (28°C) |
| Sunny Days | 317 days/yr |
Geography
| Elevation | 2 ft (1 m) |
| Area | 8.2 sq mi (21.2 km²) |
| Population Density | 101/sq mi |
| Coordinates | 29.2129°N, 90.0291°W |
| Timezone | America/Chicago |
| County | Jefferson Parish County |
| Nearest Airport | Louis Armstrong New Orleans International (MSY) 56 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 42.0 |
| Rating | Good |
Natural Hazard Risk
| Overall Risk | Relatively High |
| Risk Score | 98.7 / 100 |
| Social Vulnerability | 68.4 / 100 |
| Community Resilience | 97.7 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Hurricane | Very High |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively High |
| Hail | Relatively High |
| Strong Wind | Relatively Moderate |
| Heat Wave | Relatively High |
| Winter Weather | Relatively High |
| Lightning | Very High |
| Ice Storm | Relatively High |
| Drought | Relatively Low |
| Cold Wave | Relatively High |
| Landslide | Very Low |
| Coastal Flood | Very High |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
3 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M4.3.
| Dec 9, 2000 | 135 km S of Grand Isle, Louisiana | M4.3 | 133 km | 10 km |
| Jun 30, 1994 | 148 km S of Grand Isle, Louisiana | M4.2 | 146 km | 10 km |
| Mar 16, 2001 | 106 km SSE of Venice, Louisiana | M3.6 | 136 km | 10 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Hurricane History
27 hurricanes (Category 1+) recorded within 500 km since 1980. Strongest on record: Category 5.
| Year | Name | Category | Max Wind | Closest |
| 2024 | Francine | Category 2 | 104 mph | 95 km |
| 2021 | Ida | Category 4 | 150 mph | 21 km |
| 2020 | Laura | Category 4 | 150 mph | 300 km |
| 2020 | Zeta | Category 3 | 115 mph | 55 km |
| 2020 | Delta | Category 2 | 98 mph | 294 km |
| 2020 | Sally | Category 2 | 109 mph | 187 km |
| 2019 | Barry | Category 1 | 75 mph | 182 km |
| 2017 | Nate | Category 1 | 92 mph | 82 km |
| 2012 | Isaac | Category 1 | 81 mph | 13 km |
| 2009 | Ida | Category 1 | 86 mph | 152 km |
| 2008 | Gustav | Category 2 | 109 mph | 53 km |
| 2005 | Katrina | Category 5 | 161 mph | 43 km |
| 2005 | Rita | Category 4 | 132 mph | 272 km |
| 2005 | Cindy | Category 1 | 75 mph | 7 km |
| 2004 | Ivan | Category 4 | 132 mph | 181 km |
| 2002 | Lili | Category 4 | 144 mph | 182 km |
| 1998 | Georges | Category 2 | 109 mph | 142 km |
| 1998 | Earl | Category 2 | 98 mph | 151 km |
| 1997 | Danny | Category 1 | 81 mph | 13 km |
| 1995 | Opal | Category 4 | 150 mph | 219 km |
Source: NOAA IBTrACS (Category 1+, 1980-2026).
Tornado History
197 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF4. Total: 30 fatalities, 419 injuries.
| Date | Rating | Distance | Path | Fatalities |
| Oct 3, 1964 | EF4 | 54 km | 1.5 mi | 22 |
| Mar 22, 2022 | EF3 | 75 km | 11.5 mi | 1 |
| Feb 7, 2017 | EF3 | 89 km | 10.1 mi | 0 |
| Jan 28, 1966 | EF3 | 84 km | 0.1 mi | 0 |
| Mar 21, 1957 | EF3 | 64 km | 2.0 mi | 0 |
| Dec 14, 2022 | EF2 | 98 km | 4.7 mi | 1 |
| Dec 14, 2022 | EF2 | 74 km | 10.6 mi | 0 |
| Feb 13, 2007 | EF2 | 89 km | 1.3 mi | 1 |
| Feb 13, 2007 | EF2 | 77 km | 8.7 mi | 0 |
| Feb 2, 2006 | EF2 | 86 km | 5.5 mi | 0 |
| Apr 6, 2005 | EF2 | 21 km | 2.0 mi | 0 |
| Mar 15, 2000 | EF2 | 80 km | 3.0 mi | 0 |
| Sep 10, 1998 | EF2 | 49 km | 4.0 mi | 1 |
| May 8, 1995 | EF2 | 82 km | 0.8 mi | 0 |
| Apr 8, 1993 | EF2 | 14 km | 6.0 mi | 3 |
| Apr 22, 1983 | EF2 | 77 km | 2.0 mi | 0 |
| Jun 22, 1981 | EF2 | 82 km | 2.3 mi | 0 |
| Apr 13, 1980 | EF2 | 93 km | 3.6 mi | 0 |
| Oct 29, 1974 | EF2 | 93 km | 0.2 mi | 0 |
| Mar 16, 1972 | EF2 | 93 km | 0.5 mi | 0 |
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Wildfire History
3 wildfires (100+ acres) recorded within 100 km. Largest: BAD ROMANCE (1,305 acres, 2011).
| Year | Name | Acres Burned | Distance |
| 2011 | BAD ROMANCE | 1,305 | 95 km |
| 2010 | UNNAMED | 904 | 97 km |
| 1996 | 1 B | 846 | 99 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 54°F (12°C) | 4.7 in | Coldest |
| February | 57°F (14°C) | 4.5 in | |
| March | 63°F (17°C) | 4.5 in | |
| April | 69°F (20°C) | 3.8 in | |
| May | 75°F (24°C) | 4.9 in | |
| June | 80°F (27°C) | 4.9 in | |
| July | 82°F (28°C) | 7.1 in | Warmest, Wettest |
| August | 82°F (28°C) | 7.0 in | |
| September | 80°F (27°C) | 6.3 in | |
| October | 72°F (22°C) | 3.4 in | Driest |
| November | 64°F (18°C) | 4.2 in | |
| December | 58°F (14°C) | 4.9 in |
Grand Isle has a seasonal temperature swing of 29°F / from 54°F in January to 82°F in July. Total annual precipitation is 60.2 inches, with July being the wettest month (7.1") and October the driest (3.4").