Climate averages 1991–2020
Basseterre weather
in September.
A hot, wet month: one of the warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a hot month in Basseterre: daytime highs average 28.5°C and nights cool to about 26.3°C. By daytime temperature it is one of the warmest months of the year.
Expect about 118 mm of rain on roughly 18 days, which makes September a wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 15 min on an average September day.
The nearest other city in this atlas is Saint John’s (96 km away). In September its highs average 28.7°C, about as warm as Basseterre, with 127 mm of rain.
From September to October, average highs fall by 0.4°C to 28.1°C, and monthly rainfall rises from 118 mm to 125 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Basseterre climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 25.9°C24.1°C | 24.1°C | 30 | 10.3 | 11.211 h |
| February | 25.8°C23.9°C | 23.9°C | 21 | 7.4 | 11.612 h |
| March | 26.1°C24.0°C | 24.0°C | 20 | 6.8 | 12.012 h |
| April | 26.8°C24.5°C | 24.5°C | 33 | 8.5 | 12.513 h |
| May | 27.5°C25.4°C | 25.4°C | 61 | 11.9 | 12.913 h |
| June | 28.2°C26.0°C | 26.0°C | 47 | 10.9 | 13.113 h |
| July | 28.3°C26.1°C | 26.1°C | 74 | 14.5 | 13.113 h |
| August | 28.5°C26.3°C | 26.3°C | 91 | 17.0 | 12.713 h |
| September, selected | 28.5°C26.3°C | 26.3°C | 118 | 17.6 | 12.212 h |
| October | 28.1°C26.0°C | 26.0°C | 125 | 17.8 | 11.812 h |
| November | 27.3°C25.4°C | 25.4°C | 105 | 15.8 | 11.311 h |
| December | 26.4°C24.7°C | 24.7°C | 54 | 13.2 | 11.111 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Saint John’s in SeptemberAntigua and Barbuda · 96 kmHigh 28.7°C · Low 26.2°C · 127 mm rain
- Basse-Terre in SeptemberGuadeloupe · 179 kmHigh 30.0°C · Low 26.7°C · 107 mm rain
- Roseau in SeptemberDominica · 264 kmHigh 28.3°C · Low 26.2°C · 113 mm rain
- Fort-de-France in SeptemberMartinique · 347 kmHigh 29.0°C · Low 26.2°C · 138 mm rain
- Carolina in SeptemberPuerto Rico · 363 kmHigh 30.9°C · Low 24.6°C · 131 mm rain
- Caguas in SeptemberPuerto Rico · 367 kmHigh 30.1°C · Low 24.6°C · 168 mm rain
- San Juan in SeptemberPuerto Rico · 381 kmHigh 31.2°C · Low 24.5°C · 131 mm rain
- Bayamón in SeptemberPuerto Rico · 383 kmHigh 31.1°C · Low 24.6°C · 122 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Basseterre) is explained once on the Basseterre year overview and on the Sources, method and limits page.