Portola Valley, CA vs Phoenix, AZ

Side-by-side comparison of monthly climate normals (NOAA 1991-2020).

Portola Valley is cooler than Phoenix (57.1°F vs 72.5°F annual avg) and wetter than it (42.2 in vs 8.9 in per year). Portola Valley has a Warm-summer Mediterranean climate; Phoenix a Desert (hot) climate.

Portola Valley, CA

Annual avg
57.1°F
Annual precip
42.2 in
Warmest month
August (80.9°F)
Coldest month
December (40.1°F)
Annual swing
22.7°F
Pleasant months
3 / 12
Warm-summer Mediterranean Csb USDA Zone 9b

Phoenix, AZ

Annual avg
72.5°F
Annual precip
8.9 in
Warmest month
July (104.0°F)
Coldest month
December (42.7°F)
Annual swing
39.1°F
Pleasant months
2 / 12
Desert (hot) BWh USDA Zone 9b

Best months to visit each city

Portola Valley

J
F
M
A
M
J
J
A
S
O
N
D

Phoenix

J
F
M
A
M
J
J
A
S
O
N
D

Month-by-month comparison

Month Portola Valley Phoenix
High Low Precip High Low Precip
January 54.7°F 40.9°F 7.77 in 65.4°F 44.1°F 1.17 in
February 55.1°F 40.3°F 7.97 in 68.1°F 46.1°F 1.21 in
March 58.4°F 41.3°F 6.32 in 75.0°F 50.9°F 1.09 in
April 61.6°F 42.6°F 3.37 in 82.5°F 56.6°F 0.35 in
May 66.9°F 47.2°F 1.29 in 91.5°F 64.7°F 0.19 in
June 75.2°F 52.0°F 0.42 in 101.5°F 72.7°F 0.03 in
July 80.6°F 57.7°F 0.04 in 104.0°F 80.8°F 0.81 in
August 80.9°F 58.5°F 0.11 in 102.5°F 80.5°F 0.96 in
September 78.9°F 57.1°F 0.18 in 97.5°F 74.7°F 0.71 in
October 71.0°F 51.7°F 1.73 in 86.3°F 62.7°F 0.67 in
November 60.4°F 44.4°F 4.60 in 74.0°F 50.8°F 0.90 in
December 53.8°F 40.1°F 8.41 in 63.9°F 42.7°F 0.81 in
Portola Valley overview
Full climate profile
 Phoenix overview
Full climate profile