September in Portmore averages a daily high of 33.2°C with nights around 25.1°C. Expect roughly 7.5 wet days totalling 136.8mm. Generally workable, with some weather to plan around.
Across the year, the best time to visit Portmore is December–April.
Based on NORMAN MANLEY INTERNATIONAL, JM (11.2km), 1995–2024. 15 years of September data.