King County climate

King County Weather in September

NOAA 1991-2020 normals for Guthrie, 7.6 km from King County

Average highs run from 93°F on September 1 to 84°F on September 30, and lows from 66°F to 56°F. Normal precipitation for the month is 2.46 in over about 5 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at King County, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
89°F
Average low
61°F
Precipitation
2.46 in
Record high
108°FSep 1, 1951
Record low
34°FSep 30, 1984
Chance of a freeze
0%
Days of 90°F or more
14.7
Daylight
12 h 51 min to 11 h 52 min
Cloud cover
41%
Humidity
55%
Dew point
56°F
Wind
9.6 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 193°F66°F108°F 195156°F 195017%0%
Sep 293°F66°F106°F 195151°F 197417%0%
Sep 393°F66°F106°F 200046°F 197417%0%
Sep 492°F66°F107°F 200048°F 197417%0%
Sep 592°F65°F107°F 200049°F 196117%0%
Sep 692°F65°F105°F 199550°F 197417%0%
Sep 792°F65°F107°F 202354°F 200417%0%
Sep 891°F64°F105°F 202349°F 195717%0%
Sep 991°F64°F102°F 202644°F 202017%0%
Sep 1091°F64°F105°F 200048°F 196217%0%
Sep 1190°F63°F104°F 200046°F 195917%0%
Sep 1290°F63°F107°F 202647°F 195917%0%
Sep 1390°F63°F102°F 202645°F 198917%0%
Sep 1489°F62°F103°F 196544°F 198917%0%
Sep 1589°F62°F104°F 195642°F 199317%0%
Sep 1689°F61°F102°F 195646°F 199317%0%
Sep 1788°F61°F99°F 197247°F 197117%0%
Sep 1888°F61°F103°F 195245°F 198116%0%
Sep 1988°F60°F102°F 202447°F 197116%0%
Sep 2088°F60°F100°F 195444°F 197116%0%
Sep 2187°F60°F102°F 197738°F 198316%0%
Sep 2287°F59°F101°F 197738°F 198316%0%
Sep 2387°F59°F103°F 202341°F 199516%0%
Sep 2486°F58°F98°F 197936°F 198916%0%
Sep 2586°F58°F101°F 200539°F 200016%0%
Sep 2686°F57°F105°F 195342°F 200016%0%
Sep 2785°F57°F100°F 200943°F 200015%0%
Sep 2885°F57°F103°F 195339°F 196715%0%
Sep 2985°F56°F98°F 199441°F 198515%0%
Sep 3084°F56°F104°F 197734°F 198415%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at King County, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

September 1
sunrise 7:15 AM, sunset 8:06 PM
September 30
sunrise 7:35 AM, sunset 7:27 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00413828 (Guthrie), public domain. Records: NOAA GHCN-Daily, station USW00023007, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.