Grand Case Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Grand Case.
Climate overview of Grand Case
The climate in Grand Case, Saint Martin, is remarkably consistent, with temperatures year-round averaging 28°C (82°F). The warmest month is August at 30°C (86°F), and the coolest is February at 27°C (81°F).
Grand Case sees a moderate amount of rainfall, totalling around 918 mm (36 in) per year. It experiences a distinct dry season from January to March, creating some seasonal variation. August is the sunniest month, averaging 9.5 hours of sunshine per day.
Grand Case Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Grand Case - and find the best time to visit.
Monthly Temperature in Grand Case
In Grand Case temperatures are generally consistent throughout the year. Average maximum daytime temperatures range from a comfortable 30°C (86°F) in August, the warmest time of the year, to a comfortable 27°C (81°F) during cooler months like February.
At night, you can expect temperatures ranging from 27°C (81°F) in August to around 24°C (75°F) during February.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Grand Case
On average, Grand Case receives a reasonable amount of rainfall, with an annual precipitation of 918 mm (36 in). Significant seasonal changes in precipitation occur throughout the year. In the wettest month, October it receives high rainfall, averaging 139 mm (5.5 in) of precipitation, recorded across 20 rainy days. In contrast, the driest month March brings less rainfall, with 32 mm (1.3 in) over 13 rainy days. For more details, please visit our Grand Case Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Grand Case
Year-round, Grand Case offers plenty of sunlight to enjoy during your holiday. The difference between the sunniest month, August, with 9.5 hours of daily sunshine, and September, the least sunny month, with 7.7 hours, is minimal.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Water Temperature in Grand Case
The mean water temperature over the year ranges from 26°C (79°F) in January to 29°C (84°F) in September.
Water temperature over the year
Humidity in Grand Case by Month
The relative humidity is high throughout the year in Grand Case.
The city experiences its highest humidity in October, reaching 80%. In February, the humidity drops to its lowest level at 75%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Wind Speed in Grand Case
The mean wind speed varies between 4 m/s (8 knots) and 5 m/s (10 knots) throughout the year. It is lowest in October and November and highest during January, February, March, April, May, June, July, August, September and December. What does this mean?
The mean monthly wind speed over the year (meters per second)
Best Time to Visit Grand Case
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: January, February, March, April, May, June, July and December
- Warmest weather: May, June, July, August, September, October and November
- Most sunshine: March and August
- Fewer rainy days: February, March, April, May and June
- Best for swimming: Any time of year. The sea stays pleasantly warm year-round.
- Wettest months: July, August, September, October and November, when rainfall is highest.
- Seasonal pattern: A distinct dry season from January to March
Frequently asked questions about the climate in Grand Case
What is the best time to visit Grand Case?
January, February, March, April, May, June, July and December typically offer the most optimal weather in Grand Case. In contrast, September tends to have less optimal conditions. Grand Case has a distinct dry season from January to March.
What temperatures can I expect in Grand Case?
Daytime highs range from 27°C (81°F) in February to 30°C (86°F) in August. Nighttime lows range from 24°C (75°F) to 27°C (81°F). Temperatures stay relatively stable year-round.
How much rain does Grand Case get?
Annual rainfall is around 918 mm (36 in). October is the wettest month with 139 mm (5.5 in), while March is the driest with 32 mm (1.3 in).
How sunny is Grand Case?
Grand Case receives around 3,023 hours of sunshine per year. August is the sunniest month with 285 hours, while September is the cloudiest with just 232 hours. Overall, Grand Case enjoys abundant sunshine.
Grand Case 3-Day Forecast
Grand Case 3-Day Forecast
Grand Case on the map
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