Annual mean 22°C · wettest around September · prevailing wind NE
Warmest
28.7 °C
Coldest
23.5 °C
Wettest
90%
Windiest
3.7 m/s
Prevailing
NE
3.0 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 22°C. April is the hottest month, with highs of about 28°C; January is the coldest, with lows of about 16°C. The rainy (wet) season in San Juan runs from April to October, peaking in September with a 59% chance of rain on a given day. The dry season is November to March; February is the driest month, at 17%. Winds in San Juan are highest in January, averaging 2.7 m/s (10 km/h), and lightest in June, at 1.5 m/s (5 km/h). The prevailing wind is from the NE. The clearest skies in San Juan come in January, when the sky is typically 46% covered; June is the cloudiest month, at 71%.
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
24°C
16°C
23°C
23%
46%
2.7 m/s
61
32
45
February
25°C
16°C
24°C
17%
48%
2.7 m/s
58
38
39
March
27°C
17°C
26°C
28%
46%
2.4 m/s
52
44
29
April
28°C
18°C
28°C
40%
51%
2.2 m/s
43
47
19
May
28°C
20°C
29°C
50%
62%
1.6 m/s
38
47
14
June
27°C
20°C
28°C
57%
71%
1.5 m/s
42
43
18
July
27°C
19°C
28°C
45%
60%
2.1 m/s
46
40
23
August
27°C
19°C
28°C
54%
64%
1.9 m/s
43
43
19
September
27°C
19°C
29°C
59%
66%
1.5 m/s
40
44
16
October
26°C
19°C
27°C
54%
65%
1.8 m/s
50
39
26
November
24°C
18°C
25°C
38%
59%
2.4 m/s
59
32
39
December
24°C
17°C
24°C
24%
50%
2.6 m/s
62
31
45
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 24°C at their warmest in December, its coolest month, and 28°C in April, its warmest; the coolest hours of the day run from 16°C to 20°C through the year, and the average temperature over the year is 22°C around the clock. Rain is most likely around September and least likely around February. 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 winterDecember to February
High 24°CLow 16°CRain 22%
Winter in San Juan has typical daily highs of about 24°C and lows of about 16°C, with a 22% chance of rain on a given day.
San Juan weather in springMarch to May
High 28°CLow 18°CRain 39%
Spring in San Juan has typical daily highs of about 28°C and lows of about 18°C, with a 39% chance of rain on a given day.
San Juan weather in summerJune to August
High 27°CLow 19°CRain 52%
Summer in San Juan has typical daily highs of about 27°C and lows of about 19°C, with a 52% chance of rain on a given day.
San Juan weather in autumnSeptember to November
High 26°CLow 19°CRain 50%
Autumn in San Juan has typical daily highs of about 26°C and lows of about 19°C, with a 50% chance of rain on a given day.
When is the rainy season in San Juan?
The rainy (wet) season in San Juan runs from April to October, peaking in September with a 59% chance of rain on a given day. The dry season is November to March; February is the driest month, at 17%.
What time of year is San Juan windiest?
Winds in San Juan are highest in January, averaging 2.7 m/s (10 km/h), and lightest in June, at 1.5 m/s (5 km/h). The prevailing wind is from the NE.
What is the average temperature in San Juan year round?
The average temperature in San Juan over the whole year is 22°C. April is the hottest month, with highs of about 28°C; January is the coldest, with lows of about 16°C.