| Seattle C.O. Temperature |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Avg. Temperature |
5.2 |
6.8 |
8.1 |
10.2 |
13.4 |
16.3 |
18.5 |
18.7 |
16.0 |
11.9 |
7.9 |
5.3 |
11.6 |
| Avg. Max Temperature |
7.8 |
10.3 |
12.1 |
14.5 |
17.9 |
20.9 |
23.4 |
23.4 |
20.4 |
15.6 |
10.8 |
7.9 |
15.4 |
| Avg. Min Temperature |
2.4 |
3.3 |
4.2 |
5.9 |
8.8 |
11.8 |
13.6 |
14.0 |
11.6 |
8.3 |
5.0 |
2.8 |
7.7 |
| Days with Max Temp of 32 C or Higher |
0.0 |
0.0 |
0.0 |
0.0 |
< 0.5 |
< 0.5 |
1.0 |
< 0.5 |
< 0.5 |
0.0 |
0.0 |
0.0 |
1.0 |
| Days with Min Temp Below Freezing |
7.0 |
4.0 |
1.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
< 0.5 |
2.0 |
5.0 |
19.0 |
| | |
| Seattle C.O. Heating and Cooling |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Heating Degree Days |
735 |
580 |
570 |
438 |
276 |
123 |
44.0 |
58.0 |
144 |
357 |
561 |
725 |
4611 |
| Cooling Degree Days |
0.0 |
0.0 |
0.0 |
0.0 |
0.0 |
15.0 |
54.0 |
80.0 |
18.0 |
0.0 |
0.0 |
0.0 |
167 |
| | |
| Seattle C.O. Precipitation |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Precipitation (inches) |
5.3 |
4.0 |
3.8 |
2.5 |
1.8 |
1.6 |
0.8 |
1.2 |
1.9 |
3.2 |
5.7 |
6.0 |
38.0 |
| Days with Precipitation 0.01 inch or More |
18.0 |
15.0 |
17.0 |
14.0 |
11.0 |
9.0 |
5.0 |
6.0 |
8.0 |
11.0 |
18.0 |
18.0 |
151 |
| Monthly Snowfall (inches) |
2.9 |
0.9 |
0.6 |
0.0 |
< 0.05 |
0.0 |
0.0 |
0.0 |
0.0 |
< 0.05 |
0.7 |
2.2 |
7.3 |
| | |
| Other Seattle C.O. Weather Indicators |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Annual |
| Clear Days |
3.0 |
3.0 |
4.0 |
5.0 |
7.0 |
7.0 |
12.0 |
10.0 |
9.0 |
5.0 |
3.0 |
3.0 |
71.0 |
| Partly Cloudy Days |
5.0 |
6.0 |
8.0 |
9.0 |
10.0 |
8.0 |
10.0 |
10.0 |
8.0 |
8.0 |
6.0 |
5.0 |
93.0 |
| Cloudy Days |
23.0 |
19.0 |
19.0 |
16.0 |
14.0 |
15.0 |
9.0 |
11.0 |
13.0 |
18.0 |
21.0 |
23.0 |
201 |
| Percent of Possible Sunshine |
28.0 |
34.0 |
42.0 |
47.0 |
52.0 |
49.0 |
63.0 |
56.0 |
53.0 |
37.0 |
28.0 |
23.0 |
43.0 |