San José de Mayo weather in September

In September, San José de Mayo sees average daytime highs of 19°C and overnight lows near 9°C, with 85 mm of rain across 7.6 wet days and about 11.8 hours of daylight. It is the 9th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 18°C in the first days to 20°C by the end. The sky is clear or mostly clear about 34% 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 San José de Mayo's 8th-clearest and 1st-windiest month. For the whole year in context, see San José de Mayo's year-round climate.

Daytime high
19°
9th warmest
Overnight low
4th coldest
Rainfall
85 mm
7.6 wet days
Daylight
11 h 48 min
7:48 AM – 7:35 PM
Cloud cover
57%
8th clearest
Wind
14 km/h
1st windiest
Solar energy
4.42 kWh/m²
Travel score
6.4
out of 10

San José de Mayo is city in Uruguay, departmental capital of San José.

Density
2,117/km²
people per km²
Founded
1783

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 18°C in the first days to 20°C by the end.

A typical September day in San José de Mayo reaches about 19°C in the afternoon and slips back to 9°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 13°C and 24°C. Set against its neighbours, September runs about 2°C warmer than August and about 3°C cooler than October.

10°15°20°25°151015202530
Avg high (°C)Avg low (°C)
1189
2189
3189
4189
5189
6189
7189
8189
9189
10189
11189
12189
13189
14199
15199
16199
17199
18199
19199
20199
21199
22199
23199
24199
25199
261910
271910
282010
292010
302010

San José de Mayo weather by month

How September compares with the rest of the year at a glance. September is the 9th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 18°857.9145.9
Feb28° / 18°1028.213.36.4
Mar26° / 16°1038.112.37.1
Apr22° / 13°101811.27.1
May19° / 10°836.710.26.4
Jun16° / 797.59.85.2
Jul15° / 787.49.94.8
Aug17° / 917.710.75.8
Sep19° / 857.611.86.4
Oct22° / 11°1169.812.96.7
Nov25° / 14°1057.813.87.3
Dec28° / 16°888.314.36.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 34% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 13% of September, with mostly cloudy or overcast conditions the remaining 53%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14555
24555
34654
44654
54654
64654
74852
84852
94951
104951
115050
125149
135050
145050
155149
165149
175149
185050
195050
204951
214852
224951
234753
244753
254555
264555
274456
284357
294357
304456

Chance of precipitation in September

Any precipitation

San José de Mayo gets around 85 mm of rain over 7.6 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 26% and peaks near 28% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
127
227
327
427
527
627
727
827
926
1026
1126
1225
1325
1424
1524
1624
1724
1824
1924
2024
2124
2224
2324
2425
2525
2626
2726
2827
2927
3028

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 81% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
1801451
2811351
3811351
4811351
5811351
6821251
7821251
8811261
9811261
10811261
11811261
12821161
13821161
14821161
15821161
16821161
17821161
18831151
19831151
20831151
21821251
22831241
23821341
24811441
25811441
26801541
27791641
28781741
29781741
30771841

Wind in September

Winds average 14 km/h in September, the windiest month of the year.

Across September, daily wind ranges from about 14 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
114light breeze
214light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3014light breeze

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 8:09 AM to 7:27 AM, and sunset from 7:24 PM to 7:45 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.28:097:24
211.38:087:25
311.38:067:25
411.48:057:26
511.48:047:27
611.48:027:28
711.58:017:28
811.57:597:29
911.57:587:30
1011.67:567:30
1111.67:557:31
1211.67:537:32
1311.77:527:33
1411.77:507:33
1511.87:497:34
1611.87:487:35
1711.87:467:36
1811.97:457:36
1911.97:437:37
2011.97:427:38
2112.07:407:38
2212.07:397:39
2312.07:377:40
2412.17:367:41
2512.17:347:41
2612.27:337:42
2712.27:317:43
2812.27:307:44
2912.37:297:44
3012.37:277:45

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.42 kWh/m².

For context, solar energy here swings from a low near 2.23 kWh/m² to a high of 7.42 kWh/m² in December across the year — September's 4.42 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
13.7Moderate
23.8Moderate
33.8Moderate
43.9Moderate
53.9Moderate
64.0Moderate
74.0Bright
84.1Bright
94.1Bright
104.2Bright
114.2Bright
124.3Bright
134.3Bright
144.4Bright
154.4Bright
164.5Bright
174.5Bright
184.6Bright
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 San José de Mayo?

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

6.4
Sightseeing
6th-best month of the year
2.6
Beach & pool
9th-best month of the year

September is a reasonable time to visit San José de Mayo for sightseeing.

What to pack for San José de Mayo in September

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

In September, San José de Mayo sees daytime highs around 19°C and nights near 9°C. Little to plan around — just the basics. About 8 days see rain.

Sea temperature near San José de Mayo in September

The nearest coast averages about 14°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 35 km away) is warmest in January at about 24°C and coldest in July near 11°C.

It's comfortable for a long swim from Nov 17 to Apr 9 — about 4.7 months when the water holds above 20°C.

10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan24Warm
Feb24Warm
Mar23Refreshing
Apr19Cool
May16Cool
Jun13Bracing
Jul11Bracing
Aug12Bracing
Sep14Bracing
Oct17Cool
Nov20Refreshing
Dec23Refreshing

UV index in San José de Mayo 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 San José de Mayo peaks around January 16 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 18 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 11 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateHighVery highExtremeJan 16UV 13Jun 18UV 3
UV index (midday)Level
Jan13Extreme
Feb11Extreme
Mar10Very high
Apr6High
May4Moderate
Jun3Moderate
Jul3Moderate
Aug4Moderate
Sep6High
Oct8Very high
Nov11Extreme
Dec11Extreme
Location & terrain

Where is San José de Mayo?

San José de Mayo sits at 34.3°S, 56.7°W, 53 m above sea level, in Uruguay. The nearest listed city is Santa Lucía, 32 km away.

Santa LucíaCanelonesFloridaDelta del TigreProgresoLas PiedrasLa PazMontevideo

Topography around San José de Mayo

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of San José de Mayo.

Within 3 km, the terrain around San José de Mayo has only modest variations in elevation — a maximum elevation change of 50 m around an average of 37 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 85 m; within 80 km, only modest variations in elevation — a maximum elevation change of 202 m.

The land around San José de Mayo is covered by grassland (40%), artificial surfaces (23%) and trees (21%) within 3 km, cropland (51%) and grassland (37%) within 16 km, and grassland (39%), cropland (33%) and water (21%) within 80 km.

3 km
50 m
16 km
85 m
80 km
202 m
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Santa Lucía 32 km · Canelones 45 km · Florida 53 km · Delta del Tigre 57 km · Progreso 58 km · Las Piedras 63 km · La Paz 65 km · Montevideo 79 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 San José de Mayo (-34.339°, -56.7134°, elevation 53 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).