South San Francisco, CA vs Seattle, WA

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

South San Francisco is warmer than Seattle (58.7°F vs 53.8°F annual avg) and drier than it (19.6 in vs 36.5 in per year). Both cities share a Warm-summer Mediterranean climate (Csb).

South San Francisco, CA

Annual avg
58.7°F
Annual precip
19.6 in
Warmest month
September (74.8°F)
Coldest month
January (44.5°F)
Annual swing
14°F
Pleasant months
6 / 12
Warm-summer Mediterranean Csb USDA Zone 9b

Seattle, WA

Annual avg
53.8°F
Annual precip
36.5 in
Warmest month
August (77.4°F)
Coldest month
December (36.2°F)
Annual swing
25.8°F
Pleasant months
4 / 12
Warm-summer Mediterranean Csb USDA Zone 9a

Best months to visit each city

South San Francisco

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

Seattle

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

Month-by-month comparison

Month South San Francisco Seattle
High Low Precip High Low Precip
January 58.0°F 44.5°F 3.89 in 48.6°F 36.8°F 5.21 in
February 60.8°F 46.1°F 3.96 in 50.7°F 36.8°F 3.71 in
March 63.4°F 47.6°F 2.73 in 54.8°F 39.4°F 3.94 in
April 65.6°F 49.1°F 1.36 in 59.8°F 43.6°F 2.89 in
May 68.3°F 51.6°F 0.48 in 66.5°F 49.3°F 1.98 in
June 71.5°F 53.6°F 0.14 in 71.2°F 54.0°F 1.22 in
July 72.6°F 55.3°F 0.00 in 77.3°F 57.5°F 0.56 in
August 73.4°F 56.4°F 0.04 in 77.4°F 58.1°F 0.83 in
September 74.8°F 55.9°F 0.07 in 71.7°F 53.9°F 1.37 in
October 72.3°F 53.4°F 0.79 in 61.0°F 46.4°F 3.49 in
November 64.3°F 48.5°F 2.04 in 53.0°F 39.9°F 5.80 in
December 58.2°F 44.6°F 4.14 in 47.8°F 36.2°F 5.49 in
South San Francisco overview
Full climate profile
 Seattle overview
Full climate profile