Simi Valley, CA Weather by Month and Climate Averages

How much rain does Simi Valley get?

Simi Valley gets 16.4 in of precipitation in an average year, spread over about 35 days with measurable rain. That is fewer rainy days than 90% of the US.

February is the wettest month, with 4.6 in. August is the driest, with 0.0 in. February has the most rainy days, about 7.

The longest dry spell in the last five years lasted 200 days, to November 1, 2024.

See where Simi Valley ranks: rainiest cities in the US, US cities with the most rainy days, rainiest cities in California.

Simi Valley weather by month

Simi Valley weather in January

In January, Simi Valley averages a high of 69°F and a low of 41°F. It gets 3.7 in of precipitation over about 6 rainy days. The sun is out about 56% of daylight hours. The January record high is 93°F (1975) and the record low is 20°F (2007). January is one of the most comfortable months to visit.

Simi Valley weather in February

In February, Simi Valley averages a high of 70°F and a low of 42°F. It gets 4.6 in of precipitation over about 7 rainy days. The sun is out about 64% of daylight hours. The February record high is 97°F (2026) and the record low is 18°F (1989).

Simi Valley weather in March

In March, Simi Valley averages a high of 74°F and a low of 44°F. It gets 2.7 in of precipitation over about 6 rainy days. The sun is out about 54% of daylight hours. The March record high is 102°F (2026) and the record low is 28°F (1976). March is one of the most comfortable months to visit.

Simi Valley weather in April

In April, Simi Valley averages a high of 78°F and a low of 46°F. It gets 0.8 in of precipitation over about 2 rainy days. The sun is out about 61% of daylight hours. The April record high is 105°F (1989) and the record low is 30°F (1999). April is one of the most comfortable months to visit.

Simi Valley weather in May

In May, Simi Valley averages a high of 82°F and a low of 51°F. It gets 0.4 in of precipitation over about 2 rainy days. The sun is out about 60% of daylight hours. The May record high is 113°F (1984) and the record low is 37°F (1974).

Simi Valley weather in June

In June, Simi Valley averages a high of 89°F and a low of 55°F. It gets 0.1 in of precipitation over about 0 rainy days. The sun is out about 66% of daylight hours. The June record high is 113°F (2016) and the record low is 40°F (1971).

Simi Valley weather in July

In July, Simi Valley averages a high of 95°F and a low of 59°F. It gets 0.0 in of precipitation over about 0 rainy days. The sun is out about 82% of daylight hours. The July record high is 119°F (2006) and the record low is 46°F (1998).

Simi Valley weather in August

In August, Simi Valley averages a high of 97°F and a low of 59°F. It gets 0.0 in of precipitation over about 0 rainy days. The sun is out about 82% of daylight hours. The August record high is 116°F (1985) and the record low is 45°F (1995).

Simi Valley weather in September

In September, Simi Valley averages a high of 94°F and a low of 56°F. It gets 0.1 in of precipitation over about 1 rainy days. The sun is out about 76% of daylight hours. The September record high is 120°F (2020) and the record low is 42°F (1971).

Simi Valley weather in October

In October, Simi Valley averages a high of 86°F and a low of 51°F. It gets 0.6 in of precipitation over about 2 rainy days. The sun is out about 73% of daylight hours. The October record high is 113°F (2024) and the record low is 27°F (1971).

Simi Valley weather in November

In November, Simi Valley averages a high of 76°F and a low of 44°F. It gets 0.8 in of precipitation over about 3 rainy days. The sun is out about 69% of daylight hours. The November record high is 101°F (2006) and the record low is 24°F (2004). November is one of the most comfortable months to visit.

Simi Valley weather in December

In December, Simi Valley averages a high of 69°F and a low of 40°F. It gets 2.7 in of precipitation over about 6 rainy days. The sun is out about 52% of daylight hours. The December record high is 93°F (1989) and the record low is 20°F (1990). December is one of the most comfortable months to visit.

Sunshine, humidity and wind in Simi Valley

July is the sunniest month in Simi Valley, with sunshine about 82% of daylight hours. December is the cloudiest, at 52%. Over the year the sun shines about 66% of daylight hours. Simi Valley is sunnier than 93% of the US.

Humidity peaks in May at 63% and is lowest in November at 42%.

Simi Valley has about 105 days a year above 90°F. Simi Valley is hotter than 94% of the US.

See where Simi Valley ranks: sunniest cities in the US, cloudiest cities in the US, hottest cities in the US.

First and last freeze in Simi Valley

The first fall freeze in Simi Valley typically comes around December 1, and the last spring freeze around February 27. That leaves a frost-free growing season of about 277 days.

Simi Valley weather records

The hottest temperature on record at the Simi Valley station is 120°F, on September 6, 2020. The coldest is 18°F, on February 6, 1989.

The wettest day on record brought 6.6 in of rain, on November 29, 1970.

29 all-time records have been set at the station since 1970.

The annual mean temperature has changed by +0.6°F per decade since 1970.

The best time to visit Simi Valley

The most comfortable time to visit is typically January, March to April, and November to December, when daytime highs sit near 73°F.

Winter (December–February) is warm, with average highs around 69°F and lows near 41°F.

Spring (March–May) is warm, with average highs around 78°F and lows near 47°F.

Summer (June–August) is hot, with average highs around 94°F and lows near 58°F.

Autumn (September–November) is hot, with average highs around 85°F and lows near 51°F.

Simi Valley climate questions

How much rain does Simi Valley get?

Simi Valley gets 16.4 in of precipitation in an average year, over about 35 rainy days.

What is the wettest month in Simi Valley?

February is the wettest month in Simi Valley, with 4.6 in. August is the driest, with 0.0 in.

How many rainy days does Simi Valley have a year?

Simi Valley has about 35 days with measurable rain in an average year. February has the most, about 7.

What is the hottest month in Simi Valley?

August is the warmest month in Simi Valley, with an average high of 97°F.

What is the coldest month in Simi Valley?

December is the coldest month in Simi Valley, with an average low of 40°F.

What is the record high temperature in Simi Valley?

The record high at the Simi Valley station is 120°F, set on September 6, 2020. The record low is 18°F, on February 6, 1989.

What is the sunniest month in Simi Valley?

July is the sunniest month in Simi Valley, with sunshine about 82% of daylight hours. December is the cloudiest.

When is the first frost in Simi Valley?

The first fall freeze in Simi Valley typically comes around December 1. The last spring freeze is around February 27.

What is the best time to visit Simi Valley?

The most comfortable time to visit is typically January, March to April, and November to December, when daytime highs sit near 73°F.