Annual mean 18°C · wettest around February · prevailing wind SE
Warmest
32.9 °C
Coldest
13.3 °C
Wettest
8%
Windiest
5.2 m/s
Prevailing
SE
4.3 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in San Juan over the whole year is 18°C. January is the hottest month, with highs of about 32°C; July is the coldest, with lows of about 2°C. The rainy (wet) season in San Juan runs from October to April, peaking in February with a 19% chance of rain on a given day. The dry season is May to September; July is the driest month, at 3%. Winds in San Juan are highest in November, averaging 4.3 m/s (15 km/h), and lightest in May, at 2.5 m/s (9 km/h). The prevailing wind is from the SE. The clearest skies in San Juan come in August, when the sky is typically 29% covered; May is the cloudiest month, at 42%.
Month by month San Juan climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
32°C
23°C
30°C
19%
37%
4.0 m/s
28
57
12
February
31°C
21°C
29°C
19%
35%
3.8 m/s
36
56
16
March
28°C
18°C
25°C
13%
34%
3.4 m/s
54
53
30
April
23°C
12°C
20°C
13%
36%
2.9 m/s
74
22
62
May
18°C
7°C
15°C
5%
42%
2.5 m/s
53
2
81
June
15°C
3°C
10°C
6%
34%
2.5 m/s
20
0
72
July
15°C
2°C
10°C
3%
33%
2.5 m/s
17
0
72
August
18°C
5°C
13°C
5%
29%
3.0 m/s
41
1
78
September
22°C
10°C
17°C
10%
30%
3.5 m/s
60
10
72
October
25°C
15°C
20°C
13%
33%
4.0 m/s
66
26
58
November
29°C
20°C
25°C
15%
31%
4.3 m/s
56
53
30
December
31°C
22°C
27°C
16%
32%
4.3 m/s
42
56
21
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short San Juan weather by season
Year round, San Juan has days of about 15°C at their warmest in July, its coolest month, and 32°C in January, its warmest; the coolest hours of the day run from 2°C to 23°C through the year, and the average temperature over the year is 18°C around the clock. Rain is most likely around February and least likely around July. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
San Juan weather in winterJune to August
High 16°CLow 3°CRain 4%
Winter in San Juan has typical daily highs of about 16°C and lows of about 3°C, with a 4% chance of rain on a given day.
San Juan weather in springSeptember to November
High 25°CLow 15°CRain 13%
Spring in San Juan has typical daily highs of about 25°C and lows of about 15°C, with a 13% chance of rain on a given day.
San Juan weather in summerDecember to February
High 31°CLow 22°CRain 18%
Summer in San Juan has typical daily highs of about 31°C and lows of about 22°C, with a 18% chance of rain on a given day.
San Juan weather in autumnMarch to May
High 23°CLow 12°CRain 11%
Autumn in San Juan has typical daily highs of about 23°C and lows of about 12°C, with a 11% chance of rain on a given day.
When is the rainy season in San Juan?
The rainy (wet) season in San Juan runs from October to April, peaking in February with a 19% chance of rain on a given day. The dry season is May to September; July is the driest month, at 3%.
What time of year is San Juan windiest?
Winds in San Juan are highest in November, averaging 4.3 m/s (15 km/h), and lightest in May, at 2.5 m/s (9 km/h). The prevailing wind is from the SE.
What is the average temperature in San Juan year round?
The average temperature in San Juan over the whole year is 18°C. January is the hottest month, with highs of about 32°C; July is the coldest, with lows of about 2°C.