Climate averages 1991–2020
Portmore weather
in September.
A hot, wet month: the 3rd 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 Portmore: daytime highs average 30.7°C and nights cool to about 25.0°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 139 mm of rain on roughly 19 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 Spanish Town (8 km away). In September its highs average 30.6°C, about as warm as Portmore, with 139 mm of rain.
Among the 4 cities listed in Jamaica, Portmore ranks 3rd of 4 for the warmest September highs and joint 2nd of 4 for the driest September (rainfall, lowest first). The mean September high of those 4 cities is 31.0°C; Portmore is 0.4°C cooler than that mean.
From September to October, average highs fall by 1.1°C to 29.6°C, and monthly rainfall rises from 139 mm to 140 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
Portmore climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 28.2°C22.2°C | 22.2°C | 17 | 4.4 | 11.211 h |
| February | 28.5°C22.1°C | 22.1°C | 17 | 4.7 | 11.512 h |
| March | 29.0°C22.3°C | 22.3°C | 31 | 6.5 | 12.012 h |
| April | 29.8°C23.2°C | 23.2°C | 48 | 9.4 | 12.513 h |
| May | 30.0°C24.2°C | 24.2°C | 119 | 15.4 | 13.013 h |
| June | 30.5°C25.2°C | 25.2°C | 68 | 11.0 | 13.213 h |
| July | 31.5°C25.3°C | 25.3°C | 52 | 9.4 | 13.113 h |
| August | 31.4°C25.4°C | 25.4°C | 86 | 14.5 | 12.713 h |
| September, selected | 30.7°C25.0°C | 25.0°C | 139 | 18.8 | 12.312 h |
| October | 29.6°C24.4°C | 24.4°C | 140 | 21.3 | 11.712 h |
| November | 28.9°C23.7°C | 23.7°C | 67 | 11.6 | 11.311 h |
| December | 28.4°C22.8°C | 22.8°C | 30 | 6.2 | 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
- Spanish Town in SeptemberJamaica · 8 kmHigh 30.6°C · Low 24.8°C · 139 mm rain
- Kingston in SeptemberJamaica · 10 kmHigh 31.2°C · Low 24.2°C · 124 mm rain
- Montego Bay in SeptemberJamaica · 122 kmHigh 31.7°C · Low 25.1°C · 205 mm rain
- Santiago de Cuba in SeptemberCuba · 254 kmHigh 31.2°C · Low 24.7°C · 115 mm rain
- Manzanillo, Cuba in SeptemberCuba · 265 kmHigh 32.3°C · Low 24.4°C · 157 mm rain
- Palma Soriano in SeptemberCuba · 266 kmHigh 31.3°C · Low 23.5°C · 135 mm rain
- Contramaestre in SeptemberCuba · 267 kmHigh 32.1°C · Low 23.7°C · 122 mm rain
- Bayamo in SeptemberCuba · 268 kmHigh 32.5°C · Low 23.3°C · 170 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 Portmore) is explained once on the Portmore year overview and on the Sources, method and limits page.
Spanish Town lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.