Umán weather in September

In September, Umán sees average daytime highs of 33°C and overnight lows near 24°C, with 139 mm of rain across 19.6 wet days and about 12.1 hours of daylight. It is the 6th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 33°C through the month. The sky is clear or mostly clear about 22% of the time in September, and the air most often feels oppressive.

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 Umán's 12th-clearest and 12th-windiest month. For the whole year in context, see Umán's year-round climate.

Daytime high
33°
6th warmest
Overnight low
24°
8th coldest
Rainfall
139 mm
19.6 wet days
Daylight
12 h 06 min
5:50 AM – 5:57 PM
Cloud cover
65%
12th clearest
Wind
8 km/h
12th windiest
Solar energy
5.63 kWh/m²
Travel score
2.6
out of 10

Umán is city in Yucatán, Mexico.

Founded
1921

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 33°C through the month.

A typical September day in Umán reaches about 33°C in the afternoon and slips back to 24°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 31°C and 35°C. Set against its neighbours, September runs about 1°C cooler than August and about 2°C warmer than October.

20°25°30°35°40°151015202530
Avg high (°C)Avg low (°C)
13424
23424
33424
43424
53424
63424
73424
83424
93424
103424
113424
123424
133424
143324
153324
163324
173324
183324
193324
203324
213324
223324
233324
243324
253324
263324
273324
283324
293224
303224

How September really feels in Umán

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
23 feel dangerously hot (≥ 39°C)
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.

Umán weather by month

How September compares with the rest of the year at a glance. September is the 6th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 19°204.310.96.4
Feb31° / 19°153.311.35.6
Mar33° / 21°14311.94.3
Apr35° / 22°224.312.53.0
May36° / 24°507.8132.4
Jun35° / 25°12316.513.22.3
Jul34° / 24°8215.113.12.5
Aug34° / 24°991712.72.4
Sep33° / 24°13919.612.12.6
Oct32° / 23°8813.911.53.9
Nov30° / 21°306.4115.5
Dec29° / 19°234.310.86.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in September, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 24% of September, with mostly cloudy or overcast conditions the remaining 55%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14258
24258
34357
44357
54357
64258
74357
84357
94456
104456
114654
124654
134654
144654
154753
164753
174753
184852
194852
204753
214753
224753
234654
244654
254753
264654
274654
284555
294555
304456

Chance of precipitation in September

Any precipitation

Umán gets around 139 mm of rain over 19.6 wet days in September, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 65% and peaks near 66% on the wettest days.

0%20%40%60%80%151015202530
Rain chance (%)
163
263
364
464
564
665
765
865
965
1064
1164
1264
1363
1464
1564
1664
1764
1865
1965
2065
2165
2266
2366
2466
2566
2666
2766
2866
2965
3064

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 57% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1005941
2005842
3005842
4005842
5005743
6005743
7005743
8005743
9005743
10005743
11005842
12005842
13005842
14005842
15005842
16005842
17005842
18005842
19005842
20015742
21015742
22015742
23015742
24015742
25025741
26025741
27025741
28035641
29035641
30135640

Wind in September

Winds average 8 km/h in September, the calmest month.

Across September, daily wind ranges from about 8 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

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 5:46 AM to 5:53 AM, and sunset from 6:11 PM to 5:43 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:466:11
212.45:466:10
312.45:476:09
412.45:476:09
512.35:476:08
612.35:476:07
712.35:486:06
812.35:486:05
912.35:486:04
1012.25:486:03
1112.25:496:02
1212.25:496:01
1312.25:496:00
1412.25:495:59
1512.15:505:58
1612.15:505:57
1712.15:505:56
1812.15:505:55
1912.15:515:54
2012.05:515:53
2112.05:515:52
2212.05:515:51
2312.05:525:50
2412.05:525:49
2511.95:525:48
2611.95:525:47
2711.95:535:46
2811.95:535:45
2911.95:535:44
3011.85:535:43

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.63 kWh/m².

For context, solar energy here swings from a low near 3.95 kWh/m² to a high of 6.73 kWh/m² in May across the year — September's 5.63 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.0Intense
26.0Bright
36.0Bright
45.9Bright
55.9Bright
65.9Bright
75.9Bright
85.8Bright
95.8Bright
105.8Bright
115.8Bright
125.8Bright
135.7Bright
145.7Bright
155.7Bright
165.7Bright
175.6Bright
185.6Bright
195.5Bright
205.5Bright
215.5Bright
225.4Bright
235.4Bright
245.4Bright
255.3Bright
265.3Bright
275.3Bright
285.2Bright
295.2Bright
305.2Bright
Planning a trip in September

Hazard calendar for Umán

In seasonPeak

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

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

Umán's rainy season runs June–October, 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 Umán?

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

2.6
Sightseeing
8th-best month of the year
4.8
Beach & pool
12th-best month of the year

September is a weaker month for outdoor sightseeing in Umán.

What to pack for Umán in September

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

In September, Umán sees daytime highs around 33°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 20 days see rain.

light clothesrain gearsun protection

Sea temperature near Umán in September

The nearest coast averages about 28°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 48 km away) is warmest in September at about 28°C and coldest in January near 24°C.

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

22°24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan24Refreshing
Feb24Refreshing
Mar25Warm
Apr26Warm
May27Warm
Jun27Warm
Jul27Warm
Aug28Warm
Sep28Tropical
Oct28Warm
Nov26Warm
Dec25Warm

UV index in Umán 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 Umán peaks around June 16 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highHighJun 16UV 13Dec 17UV 6
UV index (midday)Level
Jan7High
Feb10Very high
Mar11Extreme
Apr12Extreme
May11Extreme
Jun13Extreme
Jul11Extreme
Aug12Extreme
Sep11Extreme
Oct10Very high
Nov7High
Dec6High

Air quality in Umán 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 Umán is worst in June — around 26 µg/m³ PM2.5 (moderate), about 3.4× the cleanest month (November, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJun 2025 µg/m³Nov 228 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb9Good
Mar11Good
Apr21Moderate
May20Moderate
Jun26Moderate
Jul24Moderate
Aug19Moderate
Sep15Moderate
Oct10Good
Nov8Good
Dec8Good
Location & terrain

Where is Umán?

Umán sits at 20.9°N, 89.7°W, 15 m above sea level, in Mexico. The nearest listed city is Merida, 16 km away.

Topography around Umán

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

Within 3 km, the terrain around Umán has only modest variations in elevation — a maximum elevation change of 13 m around an average of 10 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 33 m; within 80 km, only modest variations in elevation — a maximum elevation change of 152 m.

The land around Umán is covered by trees (69%) within 3 km, trees (79%) within 16 km, and trees (64%) and water (24%) within 80 km.

3 km
13 m
16 km
33 m
80 km
152 m
treesshrubsgrasslandartificial surfaceswatermangroves
September weather nearby: Merida 16 km · Hunucmá 20 km · Kanasín 21 km · Progreso 45 km · Motul 54 km · Ticul 58 km · Oxkutzkab 72 km · Izamal 76 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 Umán (20.8815°, -89.748°, elevation 15 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).