Koolbaai Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Koolbaai.
Climate overview of Koolbaai
Koolbaai, Sint Maarten, has a stable climate with little temperature variation across the year. Average daytime temperatures hover around 28°C (82°F), peaking in August at 30°C (86°F) and dipping in February to 27°C (81°F).
Annual rainfall is moderate at around 917 mm (36 in), with October being the wettest month. The city also has a distinct dry season from January to March. Sunshine peaks in August, when the city sees around 9.5 hours of sunshine per day.
Koolbaai Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Koolbaai - and find the best time to visit.
Monthly Temperature in Koolbaai
With minimal seasonal shifts, Koolbaai experiences a constant climate year-round. Average daytime temperatures reach a comfortable 30°C (86°F) in August. In February, the coolest month of the year, temperatures drop to a comfortable 27°C (81°F).
At night, temperatures range from around 27°C (81°F) in August to 24°C (75°F) in February.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Koolbaai
Generally, Koolbaai receives mid-range precipitation levels, with 917 mm (36 in) annually. Koolbaai can be quite wet during October, receiving approximately 139 mm (5.5 in) of precipitation over 20 rainy days.
In contrast, during the driest month (March), you will experience much drier conditions, with 32 mm (1.3 in) of precipitation spread across 13 rainy days. For more details, please visit our Koolbaai 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 Koolbaai
Despite minor fluctuations, Koolbaai enjoys a fairly consistent amount of sunshine throughout the year. In August, you can expect approximately 9.5 hours of daily sunshine, while even in September, Koolbaai still receives about 7.7 hours.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Water Temperature in Koolbaai
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 Koolbaai by Month
The relative humidity is high throughout the year in Koolbaai.
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 Koolbaai
The average wind speed over the year ranges from 4 m/s (8 knots) to 5 m/s (10 knots). It is lower in October and November and higher in 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 Koolbaai
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 Koolbaai
What is the best time to visit Koolbaai?
January, February, March, April, May, June, July and December typically offer the most optimal weather in Koolbaai. In contrast, September tends to have less optimal conditions. Koolbaai has a distinct dry season from January to March.
What temperatures can I expect in Koolbaai?
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 Koolbaai get?
Annual rainfall is around 917 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 Koolbaai?
Koolbaai 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, Koolbaai enjoys abundant sunshine.
Koolbaai 3-Day Forecast
Koolbaai on the map
Koolbaai is highlighted - select any city to see its climate.
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Cupecoy
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