Monthly climate guide

Miami in September

In Miami, September sits in early autumn, a shoulder-season month where the conditions can shift as the season turns. Daytime heat stands out once the sun is up, and relatively steady temperatures through the day. Daylight is moderate, so steady pacing works well. Comfort is usually predictable, so a standard day plan works well.

Annual ranking snapshot

Ranked across 12 months

September in context

How it compares to the rest of the year in Miami.

Hottest (avg)
WARMER
#3 / 12

One of the warmer months.

Wettest (avg)
WETTER
#2 / 12

Among the wetter months.

Daylight Hours
IN-BETWEEN
#6 / 12

Around the yearly average.

Windiest (avg)
WIND
#9 / 12

Close to the yearly wind average.

Highest UV
UV
#6 / 12

Near the middle of the yearly UV range.

Most Humid
HUMID
#1 / 12

The muggiest month of the year.

Climate normals

Four planning pillars

Monthly climate breakdown

A detailed look at the typical climate conditions for September.

Thermal profile

Temperature

Typical daytime high

Nighttime low
Feels like (avg)

Light window

Sunshine

12.3 h

Average daylight

UV index (max)
9
Typical sun hours
06:06 - 18:23

Wet-day pattern

Rain & Snow

Typical rainfall

Rainy days
25 days
Cloud cover (avg)
66%

Air feel

Humidity & Wind

81%

Average humidity

Wind (avg)
Wind (max gusts)

Historical daily baseline

Daily climate explorer

Pick a day to inspect the usual conditions through September in Miami. Based on a 30-year historical climate baseline, not a forecast.

Primary control

Select a day

Scroll to compare daily conditions. The summary updates with your selection.

Secondary context

Monthly trend

Day 15 selected

Median daytime highs across the month, with a softer low line.

Daily climate explorer for SeptemberMonthly trend chart for the selected climate metric, with the chosen day marked.2025303511630°C
Median temperatureMedian lowTypical range

Day 15 selected for September. Temperature 29.9°C.

Historical disruption baseline

Typical disruptions in September

Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in September.

Humidity High impact

Muggy days Measures: Muggy days (dew point >=20C). Observed about 99% of days (29.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

29.7 days / month

Share of days
~99% of days
Upper edge
Up to ~25°C (P95)
Why this matters

Muggy conditions are possible on ~30 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Heat High impact

Hot feels-like days Measures: Hot feels-like days (>=32C). Observed about 88% of days (26.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

26.4 days / month

Share of days
~88% of days
Upper edge
Up to ~38°C (P95)
Why this matters

Feels-like heat >=32C is possible on ~26 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Heat High impact

Very hot feels-like Measures: Very hot feels-like days (>=35C). Observed about 43% of days (13.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

13.0 days / month

Share of days
~43% of days
Upper edge
Up to ~38°C (P95)
Why this matters

Very hot feels-like conditions are possible on ~13 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Heat High impact

Heat stress risk Measures: High heat stress days. Observed about 43% of days (13.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

13.0 days / month

Share of days
~43% of days
Upper edge
Up to ~38°C (P95)
Why this matters

Heat stress is possible on ~13 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Rain High impact

Rain disruption Measures: Likely rain disruption days. Observed about 37% of days (11.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

11.2 days / month

Share of days
~37% of days
Upper edge
Up to ~28mm (P95)
Why this matters

Rain disruption risk appears on ~11 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Rain High impact

Washout risk Measures: Washout day risk. Observed about 36% of days (10.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

10.7 days / month

Share of days
~36% of days
Upper edge
Up to ~29mm (P95)
Why this matters

Washout conditions are possible on ~11 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Show all disruptions (29 more)
Heat High impact

Hot days Measures: Hot days (>=30C). Observed about 34% of days (10.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

10.3 days / month

Share of days
~34% of days
Upper edge
Up to ~32°C (P95)
Why this matters

Hot days are possible on ~10 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Humidity High impact

Oppressive humidity Measures: Oppressive humidity days (dew point >=24C). Observed about 32% of days (9.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

9.5 days / month

Share of days
~32% of days
Upper edge
Up to ~25°C (P95)
Why this matters

Oppressive humidity is possible on ~9 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Rain High impact

Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 17% of days (5.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

5.2 days / month

Share of days
~17% of days
Upper edge
Up to ~36mm (P95)
Why this matters

Heavy rain is possible on ~5 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Rain High impact

Washout run Measures: Multi-day washout runs. Observed about 2.6 days/month in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

2.6 days / month

Share of days
Upper edge
Up to ~31mm (P95)
Why this matters

Multi-day washout runs are possible on ~3 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Wind High impact

Strong gusts Measures: Strong gust days (>=60 km/h). Observed about 3% of days (1.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

1.0 days / month

Share of days
~3% of days
Upper edge
Up to ~102km/h (P95)
Why this matters

Strong gusts are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Wind High impact

Stormy conditions Measures: Storm-impact proxy days. Observed about 3% of days (0.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.8 days / month

Share of days
~3% of days
Upper edge
Up to ~102km/h (P95)
Why this matters

Stormy conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Rain High impact

Very heavy rain Measures: Very heavy rain days (>=25mm). Observed about 3% of days (0.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.8 days / month

Share of days
~3% of days
Upper edge
Up to ~79mm (P95)
Why this matters

Very heavy rain is possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Wind High impact

Wind disruption Measures: Disruptive wind days. Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.4 days / month

Share of days
~1% of days
Upper edge
Up to ~139km/h (P95)
Why this matters

Disruptive wind is possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Wind High impact

Severe gusts Measures: Severe gust days (>=80 km/h). Observed about 1% of days (0.3 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.3 days / month

Share of days
~1% of days
Upper edge
Up to ~147km/h (P95)
Why this matters

Severe gusts are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Rain High impact

Extreme rain Measures: Extreme rain days (>=50mm). Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.2 days / month

Share of days
~1% of days
Upper edge
Up to ~124mm (P95)
Why this matters

Extreme rain is possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Wind High impact

Wind disruption run Measures: Multi-day wind disruption runs. Observed about 0.1 days/month in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.1 days / month

Share of days
Upper edge
Up to ~174km/h (P95)
Why this matters

Multi-day disruptive wind runs are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Heat Moderate

Feels-like heatwave Measures: Feels-like heatwave runs (>=3 days). Observed about 2.1 days/month in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

2.1 days / month

Share of days
Upper edge
Up to ~38°C (P95)
Why this matters

Feels-like heatwave runs are possible on ~2 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Heat Moderate

Heatwave run Measures: Heatwave runs (>=3 hot days). Observed about 1.2 days/month in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

1.2 days / month

Share of days
Upper edge
Up to ~32°C (P95)
Why this matters

Heatwave runs are possible on ~1 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Humidity Minor

Humid days Measures: Humid days (dew point >=18C). Observed about 100% of days (30.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

30.0 days / month

Share of days
~100% of days
Upper edge
Up to ~25°C (P95)
Why this matters

Humid conditions are possible on ~30 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.

Heat Minor

Warm nights Measures: Warm nights (min >=22C). Observed about 100% of days (30.0 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

30.0 days / month

Share of days
~100% of days
Upper edge
Up to ~27°C (P95)
Why this matters

Warm nights are possible on ~30 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Rain Minor

Wet days Measures: Wet days (>=0.1mm). Observed about 91% of days (27.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

27.4 days / month

Share of days
~91% of days
Upper edge
Up to ~19mm (P95)
Why this matters

Measurable rain is possible on ~27 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Rain Minor

Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 80% of days (24.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

24.1 days / month

Share of days
~80% of days
Upper edge
Up to ~21h (P95)
Why this matters

Several rainy hours are possible on ~24 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Humidity Minor

High humidity Measures: High humidity days (RH >=80%). Observed about 66% of days (19.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

19.8 days / month

Share of days
~66% of days
Upper edge
Up to ~88% (P95)
Why this matters

High humidity is possible on ~20 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.

Heat Minor

Hot nights Measures: Hot nights (min >=25C). Observed about 66% of days (19.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

19.7 days / month

Share of days
~66% of days
Upper edge
Up to ~27°C (P95)
Why this matters

Hot nights are possible on ~20 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.

Rain Minor

Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 63% of days (18.8 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

18.8 days / month

Share of days
~63% of days
Upper edge
Up to ~22h (P95)
Why this matters

Wet-most-of-day conditions are possible on ~19 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.

Cloud Minor

Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 60% of days (18.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

18.1 days / month

Share of days
~60% of days
Upper edge
Up to ~100% (P95)
Why this matters

Cloudy skies are possible on ~18 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Cloud Minor

Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 42% of days (12.5 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

12.5 days / month

Share of days
~42% of days
Upper edge
Up to ~100% (P95)
Why this matters

Mostly cloudy skies are possible on ~13 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Humidity Minor

Convective risk Measures: Convective storm risk proxy. Observed about 37% of days (11.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

11.2 days / month

Share of days
~37% of days
Upper edge
Up to ~25°C (P95)
Why this matters

Convective risk signal appears on ~11 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Cloud Minor

Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 17% of days (5.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

5.2 days / month

Share of days
~17% of days
Upper edge
Up to ~100% (P95)
Why this matters

Overcast skies are possible on ~5 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Wind Minor

Gusty days Measures: Gusty days (>=40 km/h). Observed about 16% of days (4.7 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

4.7 days / month

Share of days
~16% of days
Upper edge
Up to ~87km/h (P95)
Why this matters

Gusty conditions are possible on ~5 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Wind Minor

Breezy days Measures: Breezy days (mean wind >=25 km/h). Observed about 4% of days (1.1 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

1.1 days / month

Share of days
~4% of days
Upper edge
Up to ~52km/h (P95)
Why this matters

Breezy conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Wind Minor

Windy days Measures: Windy days (mean wind >=35 km/h). Observed about 1% of days (0.4 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.4 days / month

Share of days
~1% of days
Upper edge
Up to ~62km/h (P95)
Why this matters

Strong mean winds are possible on ~0 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.

Visibility Minor

Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.2 days / month

Share of days
~1% of days
Upper edge
Up to ~90% (P95)
Why this matters

Fog-likely conditions are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Other Minor

Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 1% of days (0.2 days/month) in September. Historical risk signal only, not a day-by-day forecast.

Likely frequency

0.2 days / month

Share of days
~1% of days
Upper edge
Up to ~90 (P95)
Why this matters

Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.

Travel planning FAQ

Frequently asked questions

Quick answers to the weather questions you ask the most.

Is September a good time to visit Miami?

Typical September days in Miami reach highs of 29°C (84°F) with nights around 25°C (77°F). It usually feels hot by day and warm after dark. It is among the wetter months, so it is wise to have some indoor backup plans or flexible activities.

What are temperatures like in September?

Daytime temperatures in September typically peak near 29°C (84°F), while nights drop to around 25°C (77°F). Expect hot afternoons and warm evenings.

How much does it rain in September?

Rainfall in September averages 171 mm (6.7 in) across roughly 25 days. Overall it is a very wet time of year, so a light rain jacket and waterproof shoes are very handy.

How many hours of daylight are there in September?

You can expect about 12 hours of daylight in September. Sunrise is typically around 06:06 and sunset near 18:23. Daylight is fairly typical, with enough time for sightseeing.

How strong is the sun in September?

UV levels frequently reach very high levels (around 9), so strong sun protection is essential, especially around midday.

Is it windy in September?

In September, average wind speeds are around 12 km/h (7 mph), with gusts on the windiest days reaching about 44 km/h (27 mph). On the ground, it is it often feels breezy, especially in more exposed spots or along the coast.

Compare other months

Explore more