Weather in Antigua in September

How September compares

September is the 2nd warmest month of the year in Antigua and ranks 38th of 134 destinations we compare for September - see where else is hot in September. Against London's average high of 18.6°C in September, Antigua is 10.2°C warmer by day and 15.0°C warmer at night.

Daytime and night-time in September

The typical September day in Antigua peaks at 28.8°C, but that is an average: the warmest 10% of days reach 29.8°C or more. About 100% of days top 25°C and 1 in 13 pass 30°C. Nights average 26.2°C; one night in ten drops to 25.2°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest September day here reached 31.9°C (2019-09-13) and the coldest night 24.1°C (2018-09-25).

Rain in September

Wet (more than 8 rainy days): about 19 days with 1 mm or more, 124 mm in total. Year to year it varies a lot - the wettest September was 1995 with 397 mm, the driest 2015 with 36 mm. Humidity averages 79%, which makes the heat feel heavier than the thermometer suggests.

Sea temperature in September

The sea averages 28.9°C - warm enough to swim (22°c+). Depending on the year it ranges from 28.3°C to 29.4°C. This is the warmest the sea gets here all year.

Sunshine and daylight

Around 4.8 hours of sunshine a day (estimated from cloud cover), 12.1 hours of daylight: the sun rises about 05:56 and sets about 18:10 local time in mid-September. Average cloud cover is 60%.

Is September a good time to visit Antigua?

It is a reasonable choice: hot days but expect showers. The best months for Antigua on our scoring are March, February, April; months averaging 25°C or more: Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec.

Warm swimming, with little relief from the heat

The sea averages around 29°C, making September a good fit if swimming is a priority and you dislike a chilly dip. The catch is that the water offers warmth rather than much cooling, while humidity of 79% can make the air feel sticky. Pack light, loose clothing and favour accommodation where you can cool down comfortably at night. Evening temperatures remain high, so do not expect sunset to bring much relief. Keep strenuous outdoor plans away from the midday heat and leave room for shade breaks. This is a better match for travellers comfortable with persistent warmth than those who prefer crisp evenings.

Plan for rain, not uninterrupted sunshine

September is a wet choice, so a holiday built around uninterrupted outdoor time carries a clear catch. There is about 4.8 hours of sunshine within 12.1 hours of daylight each day on average: warmth does not mean clear skies throughout the day. Keep plans movable, carry a light waterproof and choose somewhere you would be comfortable spending time when it rains. Avoid relying on a particular part of the day staying dry. If your holiday dates are flexible and you want a stronger overall weather choice, March, February and April are better options. September makes more sense when hot air and warm water matter more than reliable sunshine.