What is the best way to use the California climate data?
Use the monthly high and low averages to compare county by season, then open the climate trends page for a month-by-month chart.
County count
58
Summer candidates
5
Winter candidates
6
California Climate Summary
Seasonal climate context for search and comparison
California includes 58 county records. The annual average high is 70.0℉ and the annual average low is 45.6℉ based on the monthly climate dataset.
July has the highest average high at 87.8℉, while December has the lowest average low at 35.1℉. This helps compare summer comfort and winter warmth without relying on a single daily weather snapshot.
Under the default summer filter, 5 county match the cooling criteria. Under the default winter filter, 6 county match the warm-winter criteria.
Cool-summer candidates include San Francisco County, Marin County, Alpine County.
Warm-winter candidates include Orange County, Imperial County, San Francisco County.
California Monthly Temperature Charts
State / County Average high Average low
Jan
54.3℉
35.8℉
Feb
56.8℉
37.0℉
Mar
61.2℉
39.4℉
Apr
66.0℉
41.9℉
May
73.4℉
47.7℉
Jun
81.5℉
53.2℉
Jul
87.8℉
58.3℉
Aug
87.4℉
57.7℉
Sep
83.1℉
54.1℉
Oct
73.4℉
47.1℉
Nov
61.3℉
39.9℉
Dec
53.6℉
35.1℉
Summer candidates
Jun-Aug average high no higher than 78.8℉, scroll to view all 5
| County | Average high | Average low |
|---|---|---|
| San Francisco County | 70.3℉ | 53.8℉ |
| Marin County | 71.4℉ | 51.8℉ |
| Alpine County | 72.5℉ | 46.2℉ |
| San Mateo County | 73.4℉ | 52.7℉ |
| Santa Cruz County | 76.5℉ | 52.5℉ |
Winter candidates
Dec-Feb average low no lower than 41.0℉, scroll to view all 6
| County | Average high | Average low |
|---|---|---|
| Orange County | 67.1℉ | 46.8℉ |
| Imperial County | 70.2℉ | 45.3℉ |
| San Francisco County | 57.9℉ | 44.6℉ |
| Marin County | 56.8℉ | 43.2℉ |
| San Mateo County | 58.5℉ | 42.6℉ |
| Riverside County | 64.9℉ | 42.3℉ |
California County Highlights
Rank counties by summer comfort, winter warmth, and seasonal stability
Coolest Summer
San Francisco County Average high 70.3℉ Marin County Average high 71.4℉ Alpine County Average high 72.5℉ San Mateo County Average high 73.4℉ Santa Cruz County Average high 76.5℉ Mono County Average high 77.2℉ Del Norte County Average high 77.7℉ Sierra County Average high 78.4℉ Humboldt County Average high 79.0℉ Sonoma County Average high 79.2℉Warmest Winter
Orange County Average low 46.8℉ Imperial County Average low 45.3℉ San Francisco County Average low 44.6℉ Marin County Average low 43.2℉ San Mateo County Average low 42.6℉ Riverside County Average low 42.3℉ Alameda County Average low 41.0℉ Contra Costa County Average low 41.0℉ San Diego County Average low 40.8℉ Santa Cruz County Average low 40.6℉Frequently Asked Questions
Short answers based on the same visible climate data.
What does the summer filter mean?
The default summer filter selects places where June, July, and August average highs are no higher than 78.8℉.
What does the winter filter mean?
The default winter filter selects places where December, January, and February average lows are no lower than 41.0℉.