Cozumel weather in September

In September, Cozumel sees average daytime highs of 29°C and overnight lows near 27°C, with 180 mm of rain across 21.5 wet days and about 12.1 hours of daylight. It is the 2nd-warmest and 2nd-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 32% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 24 min at the start of September to 11 h 48 min by month's end. Set against the rest of the year, September is Cozumel's 11th-clearest and 12th-windiest month. For the whole year in context, see Cozumel's year-round climate.

Daytime high
29°
2nd warmest
Overnight low
27°
10th coldest
Rainfall
180 mm
21.5 wet days
Daylight
12 h 06 min
5:39 AM – 5:46 PM
Cloud cover
60%
11th clearest
Wind
17 km/h
12th windiest
Solar energy
5.38 kWh/m²
Travel score
4.2
out of 10

Cozumel is municipal seat of Cozumel, State of Quintana Roo, Mexico.

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical September day in Cozumel reaches about 29°C in the afternoon and slips back to 27°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 29°C. Set against its neighbours, September runs on par with August and on par with October.

24°26°28°30°32°151015202530
Avg high (°C)Avg low (°C)
12927
22927
32927
42927
52927
62927
72927
82927
92927
102927
112927
122927
132927
142927
152927
162927
172927
182927
192827
202827
212827
222827
232827
242827
252826
262826
272826
282826
292826
302826

How September really feels in Cozumel

Once humidity and wind are folded in, September averages 30 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Cozumel weather by month

How September compares with the rest of the year at a glance. September is the 2nd-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan25° / 24°6411.610.96.9
Feb26° / 24°286.811.37.6
Mar26° / 24°265.711.97.8
Apr27° / 25°295.812.57.6
May28° / 26°8511136.5
Jun28° / 27°16817.513.25.0
Jul29° / 27°8214.213.15.3
Aug29° / 27°10716.612.75.0
Sep29° / 27°18021.512.14.2
Oct28° / 26°21419.811.55.0
Nov27° / 25°10312.5116.4
Dec26° / 24°6611.910.86.7

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 32% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 52%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15149
25149
35149
45050
55050
64951
74951
85050
95050
105050
115050
125050
135050
144951
154951
164951
174852
184753
194753
204753
214753
224654
234654
244456
254456
264456
274357
284357
294357
304357

Chance of precipitation in September

Any precipitation

Cozumel gets around 180 mm of rain over 21.5 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 71% and peaks near 78% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%151015202530
Rain chance (%)
164
264
365
465
566
666
766
866
967
1067
1167
1268
1368
1469
1570
1671
1772
1873
1974
2075
2176
2276
2377
2477
2578
2678
2778
2878
2978
3077

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels miserable — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the miserable band about 81% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)Miserable (%)
101387
201387
301486
401486
501486
601486
701585
801585
901585
1001585
1101585
1201585
1301585
1401684
1501684
1601684
1701783
1801783
1901882
2001981
2102080
2202179
2302278
2412376
2512475
2612574
2712673
2822771
2922771
3022870

Wind in September

Winds average 17 km/h in September, the calmest month.

Across September, daily wind ranges from about 17 km/h on the calmest days to 17 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
117light breeze
217light breeze
317light breeze
417light breeze
517light breeze
617light breeze
717light breeze
817light breeze
917light breeze
1017light breeze
1117light breeze
1217light breeze
1317light breeze
1417light breeze
1517light breeze
1617light breeze
1717light breeze
1817light breeze
1917light breeze
2017light breeze
2117light breeze
2217light breeze
2317light breeze
2417light breeze
2517light breeze
2617light breeze
2717light breeze
2817light breeze
2917light breeze
3017light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 24 min at the start of September to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 36 minutes over September. Sunrise moves from 5:35 AM to 5:42 AM, and sunset from 6:00 PM to 5:32 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:356:00
212.45:355:59
312.45:365:58
412.45:365:57
512.35:365:56
612.35:365:55
712.35:375:54
812.35:375:53
912.35:375:52
1012.25:375:51
1112.25:375:50
1212.25:385:49
1312.25:385:48
1412.25:385:48
1512.15:385:47
1612.15:395:46
1712.15:395:45
1812.15:395:44
1912.15:395:43
2012.05:405:42
2112.05:405:41
2212.05:405:40
2312.05:405:39
2412.05:415:38
2511.95:415:37
2611.95:415:36
2711.95:415:35
2811.95:425:34
2911.95:425:33
3011.85:425:32

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.38 kWh/m².

For context, solar energy here swings from a low near 3.82 kWh/m² to a high of 6.49 kWh/m² in July across the year — September's 5.38 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.8Bright
25.8Bright
35.8Bright
45.8Bright
55.7Bright
65.7Bright
75.7Bright
85.7Bright
95.6Bright
105.6Bright
115.6Bright
125.5Bright
135.5Bright
145.5Bright
155.4Bright
165.4Bright
175.3Bright
185.3Bright
195.3Bright
205.2Bright
215.2Bright
225.1Bright
235.1Bright
245.0Bright
255.0Bright
265.0Bright
275.0Bright
284.9Bright
294.9Bright
304.9Bright
Planning a trip in September

Hazard calendar for Cozumel

In seasonPeak

In September, Cozumel sits inside its atlantic hurricane and rainy season season. The full year is below, with each hazard's peak months called out.

Cozumel sits in the Atlantic hurricane belt; the season peaks August–October.

Cozumel's rainy season runs August–November, when most of the year's rain falls.

Atlantic hurricane
Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Cozumel?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

4.2
Sightseeing
12th-best month of the year
5.1
Beach & pool
12th-best month of the year

September is a reasonable time to visit Cozumel for sightseeing.

What to pack for Cozumel in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Cozumel sees daytime highs around 29°C and nights near 27°C. Pack light clothes and rain gear. Worth having: sun protection. About 22 days see rain.

light clothesrain gearsun protection

Sea temperature near Cozumel in September

The nearest coast averages about 29°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 16 km away) is warmest in September at about 29°C and coldest in February near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr27Warm
May28Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov28Tropical
Dec27Warm

UV index in Cozumel in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Cozumel peaks around April 18 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 7 (high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highHighApr 18UV 12Dec 16UV 7
UV index (midday)Level
Jan7Very high
Feb10Very high
Mar11Extreme
Apr12Extreme
May12Extreme
Jun12Extreme
Jul11Extreme
Aug12Extreme
Sep11Extreme
Oct10Very high
Nov7Very high
Dec6High

Air quality in Cozumel in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Cozumel is worst in June — around 26 µg/m³ PM2.5 (moderate), about 4.3× the cleanest month (November, 6 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJun 2126 µg/m³Nov 226 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb7Good
Mar8Good
Apr11Good
May15Moderate
Jun26Moderate
Jul24Moderate
Aug19Moderate
Sep13Moderate
Oct9Good
Nov6Good
Dec6Good
Location & terrain

Where is Cozumel?

Cozumel sits at 20.5°N, 86.9°W, 7 m above sea level, in Mexico. The nearest listed city is Playa del Carmen, 20 km away.

Topography around Cozumel

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Cozumel.

Within 3 km, the terrain around Cozumel has only modest variations in elevation — a maximum elevation change of 13 m around an average of 5 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 22 m; within 80 km, only modest variations in elevation — a maximum elevation change of 35 m.

The land around Cozumel is covered by trees (37%), artificial surfaces (30%) and water (22%) within 3 km, water (57%) and trees (38%) within 16 km, and water (53%) and trees (42%) within 80 km.

3 km
13 m
16 km
22 m
80 km
35 m
treesgrasslandartificial surfaceswatermangroves
September weather nearby: Playa del Carmen 20 km · Tulum 63 km · Cancun 76 km · Isla Mujeres 84 km · Valladolid 132 km · Tizimín 145 km · Felipe Carrillo Puerto 154 km · Chichen Itza 170 km

Mexico travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B
120 / 127 V · 60 Hz
Prices
≈ 54% of US
price level, 2025
GDP per capita
$13,889
2025
Happiness
7.0 / 10
World Happiness, 2025
Safe drinking water
43%
of population, 2024
Homicide rate
24.9
per 100k, 2023
Road deaths
12.8
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 440
Religion
Catholic 78%no religion 11%other Evangelical Churches 8%Jehovah Witness 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Cozumel (20.5004°, -86.9427°, elevation 7 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).