Annual mean 18°C · wettest around February · prevailing wind W
Warmest
33.3 °C
Coldest
15.6 °C
Wettest
33%
Windiest
3.9 m/s
Prevailing
W
3.1 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 Rancho Cucamonga over the whole year is 18°C. August is the hottest month, with highs of about 33°C; January is the coldest, with lows of about 7°C. The rainy (wet) season in Rancho Cucamonga runs from November to May, peaking in February with a 30% chance of rain on a given day. The dry season is June to October; July is the driest month, at 9%. Winds in Rancho Cucamonga are highest in May, averaging 3.1 m/s (11 km/h), and lightest in December, at 1.9 m/s (7 km/h). The prevailing wind is from the W. The clearest skies in Rancho Cucamonga come in August, when the sky is typically 14% covered; March is the cloudiest month, at 38%.
Month by month Rancho Cucamonga 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
16°C
7°C
13°C
29%
31%
2.1 m/s
40
1
80
February
17°C
8°C
14°C
30%
30%
2.4 m/s
46
4
77
March
18°C
9°C
15°C
30%
38%
2.6 m/s
51
6
77
April
22°C
11°C
19°C
23%
31%
2.9 m/s
73
16
72
May
24°C
14°C
21°C
21%
36%
3.1 m/s
78
23
65
June
29°C
18°C
26°C
13%
24%
3.1 m/s
58
56
29
July
33°C
20°C
31°C
9%
14%
3.0 m/s
22
69
4
August
33°C
20°C
31°C
18%
14%
2.8 m/s
19
70
4
September
30°C
18°C
28°C
12%
21%
2.5 m/s
47
59
19
October
27°C
14°C
24°C
19%
20%
2.2 m/s
69
42
45
November
22°C
10°C
18°C
23%
21%
2.0 m/s
72
14
73
December
17°C
8°C
14°C
27%
28%
1.9 m/s
48
1
82
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 Rancho Cucamonga weather by season
Year round, Rancho Cucamonga has days of about 16°C at their warmest in January, its coolest month, and 33°C in August, its warmest; the coolest hours of the day run from 7°C to 20°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.
Rancho Cucamonga weather in winterDecember to February
High 17°CLow 8°CRain 29%
Winter in Rancho Cucamonga has typical daily highs of about 17°C and lows of about 8°C, with a 29% chance of rain on a given day.
Rancho Cucamonga weather in springMarch to May
High 21°CLow 12°CRain 25%
Spring in Rancho Cucamonga has typical daily highs of about 21°C and lows of about 12°C, with a 25% chance of rain on a given day.
Rancho Cucamonga weather in summerJune to August
High 31°CLow 19°CRain 13%
Summer in Rancho Cucamonga has typical daily highs of about 31°C and lows of about 19°C, with a 13% chance of rain on a given day.
Rancho Cucamonga weather in autumnSeptember to November
High 26°CLow 14°CRain 18%
Autumn in Rancho Cucamonga has typical daily highs of about 26°C and lows of about 14°C, with a 18% chance of rain on a given day.
When is the rainy season in Rancho Cucamonga?
The rainy (wet) season in Rancho Cucamonga runs from November to May, peaking in February with a 30% chance of rain on a given day. The dry season is June to October; July is the driest month, at 9%.
What time of year is Rancho Cucamonga windiest?
Winds in Rancho Cucamonga are highest in May, averaging 3.1 m/s (11 km/h), and lightest in December, at 1.9 m/s (7 km/h). The prevailing wind is from the W.
What is the average temperature in Rancho Cucamonga year round?
The average temperature in Rancho Cucamonga over the whole year is 18°C. August is the hottest month, with highs of about 33°C; January is the coldest, with lows of about 7°C.