Thurston County climate

Thurston County Weather in September

NOAA 1991-2020 normals for Olympia AP, 7.2 km from Thurston County

Average highs run from 76°F on September 1 to 67°F on September 30, and lows from 49°F to 44°F. Normal precipitation for the month is 2.04 in over about 8 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 Thurston County, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
72°F
Average low
46°F
Precipitation
2.04 in
Record high
98°FSep 2, 1988
Record low
25°FSep 27, 1972
Chance of a freeze
14%
Daylight
13 h 19 min to 11 h 44 min
Cloud cover
51%
Humidity
82%
Dew point
53°F
Wind
3.6 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 176°F49°F92°F 198732°F 197322%0%
Sep 276°F49°F98°F 198836°F 196022%0%
Sep 376°F48°F91°F 197236°F 195622%0%
Sep 475°F48°F92°F 200336°F 195223%0%
Sep 575°F48°F95°F 194437°F 194723%0%
Sep 675°F48°F91°F 202436°F 199224%0%
Sep 775°F48°F96°F 198134°F 199224%0%
Sep 875°F48°F90°F 199335°F 197624%0%
Sep 974°F47°F91°F 196336°F 197625%0%
Sep 1074°F47°F93°F 194435°F 196425%0%
Sep 1174°F47°F91°F 201334°F 198826%0%
Sep 1274°F47°F88°F 194532°F 194926%0%
Sep 1373°F47°F89°F 199927°F 197027%0%
Sep 1473°F47°F90°F 195135°F 199227%0%
Sep 1573°F46°F94°F 196732°F 196928%0%
Sep 1672°F46°F90°F 196733°F 197328%0%
Sep 1772°F46°F86°F 199432°F 196529%0%
Sep 1872°F46°F86°F 199131°F 194229%0%
Sep 1971°F46°F86°F 199930°F 198330%0%
Sep 2071°F46°F92°F 197432°F 198330%0%
Sep 2171°F45°F91°F 197432°F 195531%0%
Sep 2270°F45°F91°F 199031°F 196131%0%
Sep 2370°F45°F91°F 195726°F 200032%0%
Sep 2470°F45°F93°F 194330°F 200033%0%
Sep 2569°F45°F85°F 199131°F 197233%0%
Sep 2669°F44°F86°F 202228°F 197234%0%
Sep 2768°F44°F93°F 196725°F 197234%0%
Sep 2868°F44°F88°F 201730°F 199935%0%
Sep 2967°F44°F89°F 199330°F 196136%0%
Sep 3067°F44°F83°F 198729°F 195036%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Thurston County, in percent, and of at least 0.1 inch of snowfall.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (PDT).

September 1
sunrise 6:31 AM, sunset 7:50 PM
September 30
sunrise 7:09 AM, sunset 6:53 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00024227 (Olympia AP), public domain. Records: NOAA GHCN-Daily, station USW00024227, 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.