Riverside, CA Climate & Monthly Averages

California, United States 🇺🇸 · semi-arid climate
Annual avg
65°
Hottest month
August
Coldest month
January
Rainy days / yr
40
Sunshine
10.8 h/day
Right now: 77° and sunny - see live conditions

The climate of Riverside

Located in California, United States, Riverside experiences a semi-arid climate with big day-to-night temperature swings and modest rainfall. Afternoon temperatures peak near 96°F (35°C) in August and dip to about 65°F (18°C) in January, with around 14.7 inches (374 mm) of precipitation falling across the year.

Climate quick facts

  • Hottest month: August - highs near 96°F (35°C)
  • Coldest month: January - highs near 65°F (18°C)
  • Record high: 116°F (47°C) · Record low: 28°F (-2°C) (2015–2024)
  • Wettest month: January (6 rainy days) · Sunniest: July (13.7 h sun/day)
  • Climate type: semi-arid - big day-to-night temperature swings and modest rainfall

Temperatures through the year

The warmest stretch of the year centers on August. Highs average 96°F (35°C) and overnight lows stay near 67°F (19°C). The coolest month is January, with typical highs of 65°F (18°C) and lows around 44°F (7°C). Based on 2015–2024 weather data, temperatures have reached as high as 116°F (47°C) and dropped as low as 28°F (-2°C).

Rain, sun and snow

January is usually the wettest month. It brings about 3.4 inches (87 mm) of rain over 6 days, while June is the driest. July brings the most sunshine, averaging 13.7 hours of sun a day.

Monthly climate table

Monthly averages for Riverside based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 65° 44° 6 3.4 in 8.3 h/day 63%
February 68° 45° 6 2.6 in 9.0 h/day 58%
March 70° 47° 8 2.7 in 10.2 h/day 64%
April 77° 52° 3 0.8 in 11.3 h/day 57%
May 79° 54° 3 0.5 in 12.0 h/day 62%
June 89° 60° 0 0.0 in 13.3 h/day 55%
July 95° 65° 0 0.2 in 13.7 h/day 52%
August 96° 67° 1 0.2 in 12.7 h/day 51%
September 92° 64° 2 0.4 in 11.3 h/day 53%
October 84° 58° 2 0.6 in 10.3 h/day 49%
November 74° 49° 3 1.0 in 9.4 h/day 46%
December 66° 44° 5 2.4 in 8.2 h/day 56%

Riverside month by month

Riverside weather in January

January brings highs around 65°F (18°C), lows near 44°F (7°C), about 6 wet days - typically the coldest month and the wettest month of the year in Riverside.

Riverside weather in February

February brings highs around 68°F (20°C), lows near 45°F (7°C), about 6 wet days.

Riverside weather in March

March brings highs around 70°F (21°C), lows near 47°F (9°C), about 8 wet days.

Riverside weather in April

April brings highs around 77°F (25°C), lows near 52°F (11°C), about 3 wet days.

Riverside weather in May

May brings highs around 79°F (26°C), lows near 54°F (12°C), about 3 wet days.

Riverside weather in June

June brings highs around 89°F (32°C), lows near 60°F (16°C), about 0 wet days - typically the driest month of the year in Riverside.

Riverside weather in July

July brings highs around 95°F (35°C), lows near 65°F (18°C), about 0 wet days - typically the sunniest month of the year in Riverside.

Riverside weather in August

August brings highs around 96°F (35°C), lows near 67°F (19°C), about 1 wet days - typically the hottest month of the year in Riverside.

Riverside weather in September

September brings highs around 92°F (33°C), lows near 64°F (18°C), about 2 wet days.

Riverside weather in October

October brings highs around 84°F (29°C), lows near 58°F (14°C), about 2 wet days.

Riverside weather in November

November brings highs around 74°F (24°C), lows near 49°F (9°C), about 3 wet days.

Riverside weather in December

December brings highs around 66°F (19°C), lows near 44°F (7°C), about 5 wet days.

Seasons in Riverside

Spring (March through May)

Spring in Riverside is mild and warm, with daytime highs averaging 75°F (24°C) and nights around 51°F (11°C); rain falls on about 14 days over the three months.

Summer (June through August)

Summer in Riverside turns very hot, with daytime highs averaging 93°F (34°C) and nights around 64°F (18°C); precipitation is infrequent.

Fall (September through November)

Fall in Riverside is hot, with daytime highs averaging 83°F (29°C) and nights around 57°F (14°C); precipitation is infrequent.

Winter (December through February)

Winter in Riverside is mild, with daytime highs averaging 66°F (19°C) and nights around 44°F (7°C); rain falls on about 17 days over the three months.

Climate questions, answered

What is the average temperature in Riverside?
The year-round mean is 65°F (19°C). Days typically reach 80°F (26°C) and nights settle near 54°F (12°C).
Is Riverside hot in summer?
Summers here are serious heat: 96°F (35°C) is a normal August afternoon, with a recent record of 116°F (47°C).
Is Riverside cold in winter?
Winter is gentle here: 44°F (7°C) on a typical January night, and ice is rare.
How many rainy days does Riverside get in a year?
Roughly 40 wet days a year. January carries the most rain; June the least.

Best time to visit Riverside

The best time to visit Riverside is generally January to May and November, when temperatures are at their most comfortable before or after the peak heat. Daytime temperatures in that window typically sit near 72°F (22°C).

Pack for Riverside with lightweight, breathable clothing and strong sun protection for the hot months. Evenings can feel noticeably cooler than afternoons - August nights average 67°F (19°C).

Riverside temperature records (2015-2024)

Highest recorded
116°
in September
Lowest recorded
28°
in December
Annual precipitation
14.7"
Snowy days / yr
0

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.