The highest day temperature in September 2023 was 89°F. The lowest night temperature was 86°F. The average values for day and night temperatures during September were 88.1°F и 87.6°F respectivly.

The average sea surface temperature in September 2023 for Willemstad was 88.8°F. The maximum and minimum values were 87.4°F and 90.0°F respectively.

Most of the days in September are sunny but you can also expect cloudy and gloomy days.

Precipitation total in September for Willemstad is 2.1 in.

The average wind speed in September is 18.1 mph. It makes September one of the most windless months of the year for Willemstad.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Willemstad in September is 9.0 hours.