Montevideo weather in September

In September, Montevideo sees average daytime highs of 15°C and overnight lows near 12°C, with 92 mm of rain across 8.3 wet days and about 11.8 hours of daylight. It is the 9th-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 15°C through the month. The sky is clear or mostly clear about 36% of the time in September, and the air most often feels dry.

Daylight stretches from about 11 h 12 min at the start of September to 12 h 18 min by month's end. Set against the rest of the year, September is Montevideo's 8th-clearest and 1st-windiest month. For the whole year in context, see Montevideo's year-round climate.

Daytime high
15°
9th warmest
Overnight low
12°
4th coldest
Rainfall
92 mm
8.3 wet days
Daylight
11 h 48 min
7:46 AM – 7:33 PM
Cloud cover
56%
8th clearest
Wind
23 km/h
1st windiest
Solar energy
4.39 kWh/m²
Travel score
4.6
out of 10

Montevideo is capital and largest city of Uruguay.

Air quality
Moderate
PM2.5 12 µg/m³ · 2018
Density
1,741/km²
people per km²
Founded
1726

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 15°C through the month.

A typical September day in Montevideo reaches about 15°C in the afternoon and slips back to 12°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 12°C and 17°C. Set against its neighbours, September runs about 1°C warmer than August and about 3°C cooler than October.

10°15°20°151015202530
Avg high (°C)Avg low (°C)
11411
21411
31411
41411
51411
61411
71411
81411
91411
101411
111411
121411
131412
141412
151412
161512
171512
181512
191512
201512
211512
221512
231512
241512
251512
261512
271512
281512
291513
301513

Montevideo weather by month

How September compares with the rest of the year at a glance. September is the 9th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan24° / 21°675.814.18.0
Feb24° / 21°917.413.37.5
Mar22° / 20°977.812.37.3
Apr19° / 17°1078.411.16.5
May16° / 14°877.910.25.4
Jun14° / 11°908.69.74.0
Jul12° / 10°968.79.93.4
Aug13° / 11°978.410.73.9
Sep15° / 12°928.311.84.6
Oct17° / 14°1118.812.95.7
Nov20° / 17°1017.713.86.8
Dec22° / 19°736.814.37.5

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 50%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14555
24555
34555
44555
54654
64753
74753
84753
94951
104951
115050
125248
135248
145347
155347
165446
175347
185347
195347
205347
215347
225347
235149
245149
255050
265050
274852
284852
294852
304753

Chance of precipitation in September

Any precipitation

Montevideo gets around 92 mm of rain over 8.3 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 27% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
130
230
330
430
530
630
729
829
929
1028
1128
1227
1327
1426
1526
1625
1725
1825
1925
2025
2125
2225
2326
2426
2526
2626
2727
2827
2927
3027

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 86% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
18992
28992
38992
48992
58992
688102
788102
888102
987112
1087112
1187112
1287112
1387112
1486122
1586122
1686122
1786122
1887121
1987121
2087121
2186131
2286131
2385141
2485141
2584151
2683161
2782171
2881181
2980191
3078202

Wind in September

Winds average 23 km/h in September, the windiest month of the year.

Across September, daily wind ranges from about 23 km/h on the calmest days to 23 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202530
Wind speed (km/h)Feels
123breezy
223breezy
323breezy
423breezy
523breezy
623breezy
723breezy
823breezy
923breezy
1023breezy
1123breezy
1223breezy
1323breezy
1423breezy
1523breezy
1623breezy
1723breezy
1823breezy
1923breezy
2023breezy
2123breezy
2223breezy
2323breezy
2423breezy
2523breezy
2623breezy
2723breezy
2823breezy
2923breezy
3023breezy

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 12 min at the start of September to 12 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 66 minutes over September. Sunrise moves from 8:08 AM to 7:25 AM, and sunset from 7:21 PM to 7:43 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.28:087:21
211.38:067:22
311.38:057:23
411.38:037:24
511.48:027:24
611.48:007:25
711.47:597:26
811.57:577:27
911.57:567:27
1011.67:547:28
1111.67:537:29
1211.67:527:30
1311.77:507:30
1411.77:497:31
1511.77:477:32
1611.87:467:33
1711.87:447:33
1811.97:437:34
1911.97:417:35
2011.97:407:36
2112.07:387:36
2212.07:377:37
2312.07:357:38
2412.17:347:39
2512.17:327:39
2612.27:317:40
2712.27:297:41
2812.27:287:42
2912.37:267:43
3012.37:257:43

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.39 kWh/m².

For context, solar energy here swings from a low near 2.18 kWh/m² to a high of 7.54 kWh/m² in December across the year — September's 4.39 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
13.7Moderate
23.7Moderate
33.8Moderate
43.8Moderate
53.9Moderate
63.9Moderate
74.0Moderate
84.0Bright
94.1Bright
104.1Bright
114.2Bright
124.3Bright
134.3Bright
144.3Bright
154.4Bright
164.5Bright
174.5Bright
184.5Bright
194.6Bright
204.6Bright
214.7Bright
224.7Bright
234.7Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.9Bright
294.9Bright
304.9Bright
Planning a trip in September

Is September a good time to visit Montevideo?

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

4.6
Sightseeing
9th-best month of the year
0.1
Beach & pool
9th-best month of the year

September is a reasonable time to visit Montevideo for sightseeing.

What to pack for Montevideo in September

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

In September, Montevideo sees daytime highs around 15°C and nights near 12°C. Worth packing: a warm layer, rain gear and a windbreaker. About 8 days see rain.

a warm layerrain geara windbreaker

Sea temperature near Montevideo in September

The nearest coast averages about 13°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in February at about 24°C and coldest in July near 11°C.

It's comfortable for a long swim from Nov 27 to Apr 9 — about 4.4 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan23Refreshing
Feb24Refreshing
Mar22Refreshing
Apr19Cool
May16Cool
Jun13Bracing
Jul11Bracing
Aug12Bracing
Sep13Bracing
Oct16Cool
Nov19Cool
Dec22Refreshing

UV index in Montevideo in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Montevideo peaks around January 17 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 18 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateHighVery highExtremeJan 17UV 12Jun 18UV 2
UV index (midday)Level
Jan12Extreme
Feb11Extreme
Mar10Very high
Apr6High
May3Moderate
Jun2Moderate
Jul3Moderate
Aug4Moderate
Sep6High
Oct8Very high
Nov11Extreme
Dec11Extreme

Air quality in Montevideo 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 Montevideo is worst in August — around 16 µg/m³ PM2.5 (moderate), about 1.6× the cleanest month (February, 10 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Montevideo's WHO annual average of 12 µg/m³.

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodAug 1416 µg/m³Feb 2210 µg/m³
PM2.5 (µg/m³)Level
Jan12Good
Feb10Good
Mar10Good
Apr11Good
May12Moderate
Jun13Moderate
Jul15Moderate
Aug16Moderate
Sep14Moderate
Oct12Good
Nov10Good
Dec10Good
Location & terrain

Where is Montevideo?

Montevideo sits at 34.9°S, 56.2°W, 34 m above sea level, in Uruguay. The nearest listed city is Paso de Carrasco, 13 km away.

Canelones

Topography around Montevideo

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

Within 3 km, the terrain around Montevideo has only modest variations in elevation — a maximum elevation change of 56 m around an average of 16 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 130 m; within 80 km, significant variations in elevation — a maximum elevation change of 394 m.

The land around Montevideo is covered by artificial surfaces (55%) and water (38%) within 3 km, water (53%) and artificial surfaces (21%) within 16 km, and water (43%) and grassland (27%) within 80 km.

3 km
56 m
16 km
130 m
80 km
394 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: Paso de Carrasco 13 km · La Paz 16 km · Las Piedras 19 km · Delta del Tigre 22 km · Barros Blancos 24 km · Progreso 26 km · Pando 29 km · Canelones 43 km

Uruguay travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F / I / L
230 V · 50 Hz
Prices
≈ 66% of US
price level, 2025
GDP per capita
$25,216
2025
Happiness
6.6 / 10
World Happiness, 2025
Homicide rate
11.2
per 100k, 2023
Road deaths
14.8
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 542
Religion
none 47%Roman Catholic 37%Protestant 15%atheist 10%

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 Montevideo (-34.9033°, -56.1882°, elevation 34 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. 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).