May weather forecastGrand Isle, LA
May
Weather in May
The weather in Grand Isle in May bears the hallmark of the ensuing summer season as the temperature ascends, with averages peaking at 80.1°F (26.7°C). Daylight hours stretched to 13.6 hours, accompanied by a proportional expansion in sunshine duration, confirming the impending arrival of summer. A noticeable hike in sea temperature is well-aligned with the transition to summer, providing an ideal setup for water-based recreational activities. Despite slightly increased rainfall, the weather in May is a period of warm, sunny delight, making it an ideal time for visiting the city.Temperature
The shift from April to May in Grand Isle is marked by a slight increase in the average high-temperature, moving from 74.3°F (23.5°C) to a still moderately hot 80.1°F (26.7°C). Grand Isle sustains a near constant temperature throughout May, with nighttime averages of 73.2°F (22.9°C).Humidity
In Grand Isle, the average relative humidity in May is 76%.Rainfall
In Grand Isle, during May, the rain falls for 10 days and regularly aggregates up to 1.22" (31mm) of precipitation. Throughout the year, there are 151.9 rainfall days, and 22.01" (559mm) of precipitation is accumulated.Snowfall
In Grand Isle, snow does not fall in February through December.Ocean temperature
In May, the average ocean temperature is 78.4°F (25.8°C).Note: Water temperatures between 77°F (25°C) and 84.2°F (29°C) are ideal for all water activities, offering enjoyment without causing discomfort over extended periods.
Daylight
The average length of the day in May is 13h and 37min.On the first day of the month, sunrise is at 6:17 am and sunset at 7:36 pm. On the last day of May, sunrise is at 6:01 am and sunset at 7:54 pm CDT.
Sunshine
The average sunshine in May is 10.9h.UV index
The months with the highest UV index are May through September, with an average maximum UV index of 7. A UV Index reading of 6 to 7 represents a high threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: In May, the maximum UV index of 7 translates into these guidelines:
Adhere to precautions and respect sun safety doctrines. Avoiding sunburn is vital. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. Boost your sun resistance with garments that are densely woven yet spacious. Attention! The combination of sand and water reflections enhances UV ray intensity.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in May
Grand Isle, LA
- Average high temperature in May: 80.1°F
The warmest months (with the highest average high temperature) are July and August (86.9°F).
The month with the lowest average high temperature is January (61.7°F).
- Average low temperature in May: 73.2°F
The month with the highest average low temperature is August (81.3°F).
The coldest month (with the lowest average low temperature) is January (53.1°F).
Average pressure in May
Grand Isle, LA
- Average pressure in May: 29.99"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is September (29.96"Hg).
Average wind speed in May
Grand Isle, LA
- Average wind speed in May: 10.1mph
The windiest month (with the highest average wind speed) is January (12.4mph).
The calmest month (with the lowest average wind speed) is July (8mph).
Average humidity in May
Grand Isle, LA
- Average humidity in May: 76%
The months with the highest relative humidity are February and December (78%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Grand Isle, LA
- Average rainfall in May: 1.22"
The wettest month (with the highest rainfall) is August (4.72").
The driest months (with the least rainfall) are February and April (0.87").
Average rainfall days in May
Grand Isle, LA
- Average rainfall days in May: 10 days
The month with the highest number of rainy days is August (20.7 days).
The month with the least rainy days is November (7.5 days).
Average snowfall days in May
Grand Isle, LA
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (0.1 days).
The months with the least snowfall days are February, March, April, May, June, July, August, September, October, November and December (0 days).
Average sea temperature in May
Grand Isle, LA
- Average sea temperature in May: 78.5°F
The best month for swimming (with the highest average sea temperature) is August (87.5°F).
The coldest month (with the lowest average sea temperature) is January (61.4°F).
Average daylight in May /
Average sunshine in May
Grand Isle, LA
- Average daylight in May: 13h and 36min
The month with the longest days is June (Average daylight: 14h and 0min).
The month with the shortest days is December (Average daylight: 10h and 18min).
- Average sunshine in May: 10h and 54min
The month with the most sunshine is June (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 24min).
Average sunshine days in May
Grand Isle, LA
- Average sunshine days in May: 17.4 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is August (6.5 days).
Average UV index in May
Grand Isle, LA
- Average UV index in May: 7
The months with the highest UV index are May, June, July, August and September (UV index 7).
The months with the lowest UV index are January and December (UV index 4).
Average cloud cover in May
Grand Isle, LA
- Average cloud cover in May: 23
The month with the most cloud cover is December (Cloud cover 42).
The month with the least cloud cover is May (Cloud cover 23).
Average visibility in May
Grand Isle, LA
- Average visibility in May: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
