Weather in Miami in September

How September compares

September is the 3rd warmest month of the year in Miami and ranks 28th of 134 destinations we compare for September - see where else is hot in September. Within United States it is 4th of 6 (United States in September). Against London's average high of 18.6°C in September, Miami is 10.7°C warmer by day and 14.3°C warmer at night.

Daytime and night-time in September

The typical September day in Miami peaks at 29.3°C, but that is an average: the warmest 10% of days reach 30.6°C or more. About 100% of days top 25°C and 1 in 4 pass 30°C. Nights average 25.5°C; one night in ten drops to 24.4°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest September day here reached 32.7°C (2020-09-04) and the coldest night 22.2°C (2019-09-25).

Rain in September

Wet (more than 8 rainy days): about 22 days with 1 mm or more, 158 mm in total. Year to year it varies a lot - the wettest September was 2017 with 298 mm, the driest 2002 with 73 mm. Humidity averages 81%, which makes the heat feel heavier than the thermometer suggests.

Sea temperature in September

The sea averages 29.3°C - warm enough to swim (22°c+). Depending on the year it ranges from 28.9°C to 29.8°C. For the warmest sea here, come in August (29.9°C).

Sunshine and daylight

Around 4.1 hours of sunshine a day (estimated from cloud cover), 12.1 hours of daylight: the sun rises about 07:07 and sets about 19:25 local time in mid-September. Average cloud cover is 66%.

Is September a good time to visit Miami?

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

Hot days, warm nights and little relief from the sea

September feels substantially warmer than early autumn at home: Miami's average daytime high is 10.7°C above London's. Humidity of 81% makes that warmth more demanding, so lightweight clothing and a relaxed pace are sensible choices. Avoid packing your most active plans into the middle of the day, and do not expect evenings to feel cool: the average night low is 25.5°C. The sea averages 29.3°C, making swimming an easy choice if you dislike cold water, though it will offer limited cooling. This is a better fit for heat lovers than for travellers who want crisp evenings or comfortable conditions for long walks.

Plan around wet weather, not guaranteed sunshine

Rain is the main catch. With about 22 rainy days, it makes sense to have indoor alternatives and carry a light waterproof rather than assume you can spend every day outside. That figure does not mean it rains all day, but it does make a completely dry holiday a poor expectation. Sunshine averages about 4.1 hours within 12.1 hours of daylight, so long days should not be confused with clear skies. Keep outdoor plans movable and take advantage of dry spells when they arrive. September works if warmth matters more than sunshine; it is harder to recommend if rain would spoil the trip.