Annual mean 17°C · wettest around March · prevailing wind W
Warmest
29.1 °C
Coldest
17.0 °C
Wettest
19%
Windiest
4.0 m/s
Prevailing
W
3.5 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 Marcos over the whole year is 17°C. August is the hottest month, with highs of about 28°C; January is the coldest, with lows of about 8°C. San Marcos has no sharply defined rainy season: the chance of rain on a given day runs from 4% in July, the driest month, to 18% in March, the wettest. Winds in San Marcos are highest in May, averaging 2.5 m/s (9 km/h), and lightest in December, at 1.8 m/s (6 km/h). The prevailing wind is from the W. The clearest skies in San Marcos come in November, when the sky is typically 23% covered; May is the cloudiest month, at 56%.
Month by month San Marcos 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
18°C
8°C
14°C
17%
32%
2.0 m/s
51
2
88
February
18°C
8°C
15°C
14%
34%
2.3 m/s
52
4
83
March
18°C
9°C
15°C
18%
43%
2.4 m/s
53
3
86
April
20°C
11°C
18°C
9%
41%
2.4 m/s
73
10
82
May
21°C
14°C
19°C
7%
56%
2.5 m/s
82
12
81
June
24°C
16°C
23°C
4%
47%
2.4 m/s
80
32
57
July
27°C
19°C
27°C
4%
32%
2.3 m/s
58
57
28
August
28°C
19°C
28°C
4%
30%
2.2 m/s
52
64
20
September
27°C
18°C
26°C
6%
34%
2.1 m/s
65
51
33
October
25°C
14°C
23°C
8%
29%
2.0 m/s
80
33
55
November
22°C
10°C
19°C
10%
23%
1.9 m/s
81
11
78
December
18°C
8°C
15°C
14%
29%
1.8 m/s
61
1
88
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 Marcos weather by season
Year round, San Marcos has days of about 18°C at their warmest in January, its coolest month, and 28°C in August, its warmest; the coolest hours of the day run from 8°C to 19°C through the year, and the average temperature over the year is 17°C around the clock. Rain is most likely around March 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 Marcos weather in winterDecember to February
High 18°CLow 8°CRain 15%
Winter in San Marcos has typical daily highs of about 18°C and lows of about 8°C, with a 15% chance of rain on a given day.
San Marcos weather in springMarch to May
High 20°CLow 11°CRain 11%
Spring in San Marcos has typical daily highs of about 20°C and lows of about 11°C, with a 11% chance of rain on a given day.
San Marcos weather in summerJune to August
High 27°CLow 18°CRain 4%
Summer in San Marcos has typical daily highs of about 27°C and lows of about 18°C, with a 4% chance of rain on a given day.
San Marcos weather in autumnSeptember to November
High 25°CLow 14°CRain 8%
Autumn in San Marcos has typical daily highs of about 25°C and lows of about 14°C, with a 8% chance of rain on a given day.
When is the rainy season in San Marcos?
San Marcos has no sharply defined rainy season: the chance of rain on a given day runs from 4% in July, the driest month, to 18% in March, the wettest.
What time of year is San Marcos windiest?
Winds in San Marcos are highest in May, averaging 2.5 m/s (9 km/h), and lightest in December, at 1.8 m/s (6 km/h). The prevailing wind is from the W.
What is the average temperature in San Marcos year round?
The average temperature in San Marcos over the whole year is 17°C. August is the hottest month, with highs of about 28°C; January is the coldest, with lows of about 8°C.