San Francisco weather in May

In May, San Francisco sees average daytime highs of 20°C and overnight lows near 11°C, with 47 mm of rain across 5.5 wet days and about 10.4 hours of daylight. It is the 9th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 22°C in the first days to 19°C by the end. The sky is clear or mostly clear about 39% of the time in May, and the air most often feels dry.

Daylight stretches from about 10 h 48 min at the start of May to 10 h 06 min by month's end. Set against the rest of the year, May is San Francisco's 12th-clearest and 8th-windiest month. For the whole year in context, see San Francisco's year-round climate.

Daytime high
20°
9th warmest
Overnight low
11°
5th coldest
Rainfall
47 mm
5.5 wet days
Daylight
10 h 24 min
7:52 AM – 6:17 PM
Cloud cover
54%
12th clearest
Wind
12 km/h
8th windiest
Solar energy
2.92 kWh/m²
Travel score
7.1
out of 10

San Francisco is city in Argentina.

Founded
1886

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 22°C in the first days to 19°C by the end.

A typical May day in San Francisco reaches about 20°C in the afternoon and slips back to 11°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 26°C. Set against its neighbours, May runs about 4°C cooler than April and about 3°C warmer than June.

10°20°30°151015202531
Avg high (°C)Avg low (°C)
12212
22212
32212
42212
52212
62212
72212
82212
92112
102111
112111
122111
132111
142111
152111
162011
172011
182011
192010
202010
212010
222010
231910
241910
251910
26199
27199
28199
29199
30199
31199

San Francisco weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 19°1199.113.85.3
Feb29° / 19°1159.113.15.8
Mar27° / 17°1389.212.26.8
Apr24° / 14°1008.211.37.4
May20° / 11°475.510.47.1
Jun18° / 304.3106.6
Jul17° / 203.510.26.7
Aug20° / 393.810.97.6
Sep22° / 11°515.411.87.8
Oct25° / 14°1169.612.87.2
Nov28° / 16°1198.913.66.6
Dec30° / 18°1289.6145.5

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 39% of the time in May, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 12% of May, with mostly cloudy or overcast conditions the remaining 48%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15842
25743
35743
45644
55644
65545
75545
85446
95446
105347
115248
125248
135149
145149
155149
164951
174951
184951
194852
204852
214852
224852
234852
244852
255050
265050
275050
285149
295149
305248
315347

Chance of precipitation in May

Any precipitation

San Francisco gets around 47 mm of rain over 5.5 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 18% and peaks near 23% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%151015202531
Rain chance (%)
123
223
322
422
521
621
720
820
919
1019
1119
1219
1318
1418
1518
1618
1718
1818
1917
2017
2117
2217
2316
2416
2515
2615
2715
2814
2914
3013
3113

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 67% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
154201691
255191691
355191691
457191581
557191581
658191571
759191471
861191361
961191361
1062201251
1162201251
1264201141
1364201141
1465201140
1565201140
1667191030
1768191030
1869181030
1969181030
2070171030
2171161030
2272151030
2372151030
247414930
257414930
267513930
277613830
287713820
297813720
307912720
317912720

Wind in May

Winds average 12 km/h in May.

Across May, daily wind ranges from about 12 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
112calm
212calm
312calm
412calm
512calm
612calm
712calm
812calm
912calm
1012calm
1112calm
1212calm
1312calm
1412calm
1512calm
1612calm
1712calm
1812calm
1912calm
2012calm
2112calm
2212calm
2312calm
2412calm
2512calm
2612calm
2712calm
2812calm
2912calm
3012calm
3112calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 10 h 48 min at the start of May to 10 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 42 minutes over May. Sunrise moves from 7:42 AM to 8:02 AM, and sunset from 6:29 PM to 6:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.87:426:29
210.87:436:28
310.77:436:27
410.77:446:26
510.77:456:25
610.77:456:25
710.67:466:24
810.67:476:23
910.67:486:22
1010.57:486:21
1110.57:496:20
1210.57:506:20
1310.57:506:19
1410.57:516:18
1510.47:526:17
1610.47:526:17
1710.47:536:16
1810.47:546:15
1910.37:546:15
2010.37:556:14
2110.37:566:14
2210.37:566:13
2310.37:576:13
2410.27:586:12
2510.27:586:12
2610.27:596:11
2710.28:006:11
2810.28:006:10
2910.28:016:10
3010.18:016:10
3110.18:026:09

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 2.92 kWh/m².

For context, solar energy here swings from a low near 2.55 kWh/m² to a high of 7.19 kWh/m² in December across the year — May's 2.92 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.3Moderate
23.3Moderate
33.3Moderate
43.3Moderate
53.2Moderate
63.2Moderate
73.2Moderate
83.1Moderate
93.1Moderate
103.1Moderate
113.0Moderate
123.0Moderate
133.0Moderate
143.0Moderate
152.9Moderate
162.9Moderate
172.9Moderate
182.8Moderate
192.8Moderate
202.8Moderate
212.8Moderate
222.7Moderate
232.7Moderate
242.7Moderate
252.7Moderate
262.7Moderate
272.7Moderate
282.6Moderate
292.6Moderate
302.6Moderate
312.6Moderate
Planning a trip in May

Is May a good time to visit San Francisco?

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

7.1
Sightseeing
5th-best month of the year
4.0
Beach & pool
9th-best month of the year

May is one of the better times to visit San Francisco for general sightseeing.

What to pack for San Francisco in May

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

In May, San Francisco sees daytime highs around 20°C and nights near 11°C. Little to plan around — just the basics. About 6 days see rain.

UV index in San Francisco in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 4 — 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 Francisco peaks around January 17 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 21 at about 3 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeModerateHighVery highExtremeJan 17UV 14Jun 21UV 3
UV index (midday)Level
Jan14Extreme
Feb13Extreme
Mar11Extreme
Apr7High
May4Moderate
Jun3Moderate
Jul3Moderate
Aug5Moderate
Sep7High
Oct10Very high
Nov11Extreme
Dec13Extreme
Location & terrain

Where is San Francisco?

San Francisco sits at 31.4°S, 62.1°W, 120 m above sea level, in Argentina. The nearest listed city is San Jorge, 57 km away.

Topography around San Francisco

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

Within 3 km, the terrain around San Francisco has only modest variations in elevation — a maximum elevation change of 13 m around an average of 114 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 24 m; within 80 km, only modest variations in elevation — a maximum elevation change of 103 m.

The land around San Francisco is covered by artificial surfaces (50%) and cropland (30%) within 3 km, cropland (94%) within 16 km, and cropland (88%) within 80 km.

3 km
13 m
16 km
24 m
80 km
103 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: San Jorge 57 km · Rafaela 60 km · Sunchales 73 km · Las Varillas 78 km · Morteros 80 km · Arroyito 92 km · Gálvez 106 km · Esperanza 109 km

Argentina travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / I
220 V · 50 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$14,898
2025
Happiness
6.4 / 10
World Happiness, 2025
Homicide rate
4.5
per 100k, 2023
Road deaths
14.1
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
High
EF EPI 575
Religion
Roman Catholic 63%none 19%Evangelical 15%Jehovah's Witness and Church of Jesus Christ 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 San Francisco (-31.425°, -62.084°, elevation 120 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. 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).