Portola, CA

Climate overview — based on NOAA 1991-2020 normals from PORTOLA, CA US.

Dsb Mediterranean continental (warm summer) climate 7a USDA hardiness Zone 7a

Year-round temperatures (°F)

10° 30° 50° 70° 90° J F M A M J J A S O N D
Avg high Avg low

Climate summary

Portola has an annual average temperature of 46.7°F with about 23.3 inches of precipitation per year and 37.8 inches of snow. The warmest month is July (average high 86.4°F), and the coldest is January (average low 19.3°F). December is typically the wettest month (4.28 in) and August the driest (0.30 in). Snow typically falls from October through May.

Annual swing
34.8°F
warmest to coldest month
Heating need
6,591
Cooling need
15

Best time to visit Portola

Full guide →

Climate change signal

All-time records →

39 of 366 (10.7%) of Portola's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.

1910s
29
1920s
105
1930s
43
1940s
22
1950s
28
1960s
18
1970s
16
1980s
25
1990s
12
2000s
19
2010s
27
2020s
22

Bars: number of all-time daily heat records still standing that were set in each decade.

Monthly averages

Month Avg High Avg Low Avg Temp Precipitation Snow Rainy days
January 43.0°F 19.3°F 31.1°F 4.16 in 11.7 in 9
February 46.0°F 21.4°F 33.7°F 3.93 in 7.6 in 9
March 51.6°F 25.3°F 38.4°F 3.57 in 6.4 in 8
April 57.7°F 29.1°F 43.4°F 1.55 in 1.8 in 6
May 67.0°F 35.1°F 51.0°F 1.15 in 0.2 in 6
June 77.2°F 40.1°F 58.7°F 0.52 in 3
July 86.4°F 44.6°F 65.5°F 0.34 in 1
August 85.2°F 42.6°F 63.9°F 0.30 in 1
September 78.8°F 37.1°F 58.0°F 0.44 in 0.1 in 2
October 66.4°F 29.7°F 48.1°F 1.07 in 0.4 in 4
November 52.5°F 24.1°F 38.3°F 2.03 in 2.4 in 6
December 42.1°F 19.4°F 30.7°F 4.28 in 7.2 in 8

Climate twins of Portola

Why these? →

The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).

Frost dates
Last spring / first fall frost
All-time records
Hottest, coldest, wettest
Planting calendar
What to plant, and when

Compare Portola to another city