Linn County climate

Linn County Weather in September

NOAA 1991-2020 normals for Foster Dam, 13.8 km from Linn County

Average highs run from 80°F on September 1 to 71°F on September 30, and lows from 49°F to 45°F. Normal precipitation for the month is 1.99 in over about 7 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 Linn County, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
76°F
Average low
47°F
Precipitation
1.99 in
Record high
103°FSep 3, 1988
Record low
27°FSep 24, 1908
Chance of a freeze
5%
Days of 90°F or more
2.3
Daylight
13 h 13 min to 11 h 45 min
Cloud cover
42%
Humidity
65%
Dew point
45°F
Wind
3.8 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 180°F49°F101°F 198737°F 191316%0%
Sep 280°F49°F99°F 193437°F 194617%0%
Sep 380°F48°F103°F 198838°F 191317%0%
Sep 480°F48°F96°F 201739°F 200218%0%
Sep 580°F48°F103°F 194437°F 189518%0%
Sep 679°F48°F99°F 202437°F 189519%0%
Sep 779°F48°F97°F 195837°F 191019%0%
Sep 879°F48°F98°F 194436°F 189620%0%
Sep 979°F48°F97°F 194434°F 189520%0%
Sep 1078°F48°F101°F 194436°F 195220%0%
Sep 1178°F48°F96°F 192236°F 195221%0%
Sep 1278°F47°F94°F 192234°F 192121%0%
Sep 1378°F47°F95°F 195133°F 192122%0%
Sep 1477°F47°F98°F 193733°F 197022%0%
Sep 1577°F47°F94°F 195734°F 192123%0%
Sep 1677°F47°F98°F 196735°F 190824%0%
Sep 1776°F47°F92°F 191833°F 191124%0%
Sep 1876°F47°F93°F 199134°F 198825%0%
Sep 1976°F46°F91°F 199134°F 190725%0%
Sep 2075°F46°F94°F 197436°F 195726%0%
Sep 2175°F46°F95°F 194730°F 189526%0%
Sep 2275°F46°F95°F 194731°F 190427%0%
Sep 2374°F46°F95°F 194335°F 190827%0%
Sep 2474°F46°F93°F 194327°F 190828%0%
Sep 2573°F46°F97°F 197430°F 190828%0%
Sep 2673°F45°F93°F 199132°F 192629%0%
Sep 2773°F45°F94°F 196732°F 197229%0%
Sep 2872°F45°F98°F 200332°F 190230%0%
Sep 2972°F45°F89°F 193234°F 196131%0%
Sep 3071°F45°F88°F 198732°F 190331%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Linn 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 6:33 AM, sunset 7:46 PM
September 30
sunrise 7:07 AM, sunset 6:52 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00353047 (Foster Dam), public domain. Records: NOAA GHCN-Daily, station USC00351862, 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.