Roslyn Weather in September
Average highs run from 78°F on September 1 to 67°F on September 30, and lows from 47°F to 38°F. Normal precipitation for the month is 0.90 in.
September day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
September at a glance
- Average high
- 73°F
- Average low
- 43°F
- Precipitation
- 0.90 in
- Record high
- 91°FSep 4, 1988
- Record low
- 26°FSep 27, 1972
- Chance of a freeze
- 67%
- Days of 90°F or more
- 0.9
- Daylight
- 13 h 21 min to 11 h 43 min
- Cloud cover
- 48%
- Humidity
- 71%
- Dew point
- 41°F
- Wind
- 4.3 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| Sep 1 | 78°F | 47°F | 83°F 1998 | 35°F 1973 | |
| Sep 2 | 78°F | 47°F | 85°F 1988 | 36°F 1960 | |
| Sep 3 | 77°F | 47°F | 89°F 1988 | 36°F 1969 | |
| Sep 4 | 77°F | 46°F | 91°F 1988 | 37°F 1947 | |
| Sep 5 | 77°F | 46°F | 86°F 2024 | 34°F 2002 | |
| Sep 6 | 76°F | 46°F | 86°F 1944 | 34°F 1976 | |
| Sep 7 | 76°F | 45°F | 85°F 1958 | 36°F 1952 | |
| Sep 8 | 76°F | 45°F | 81°F 1981 | 35°F 1959 | |
| Sep 9 | 76°F | 45°F | 86°F 1944 | 34°F 1988 | |
| Sep 10 | 75°F | 44°F | 87°F 1944 | 35°F 1988 | |
| Sep 11 | 75°F | 44°F | 86°F 1944 | 33°F 2012 | |
| Sep 12 | 75°F | 44°F | 78°F 2009 | 35°F 1967 | |
| Sep 13 | 74°F | 44°F | 79°F 2002 | 31°F 1970 | |
| Sep 14 | 74°F | 43°F | 81°F 2013 | 34°F 1969 | |
| Sep 15 | 74°F | 43°F | 78°F 1998 | 33°F 1955 | |
| Sep 16 | 73°F | 43°F | 79°F 1981 | 29°F 1946 | |
| Sep 17 | 73°F | 42°F | 81°F 1981 | 30°F 1978 | |
| Sep 18 | 72°F | 42°F | 77°F 1979 | 31°F 1983 | |
| Sep 19 | 72°F | 42°F | 78°F 2012 | 32°F 1972 | |
| Sep 20 | 72°F | 41°F | 82°F 2012 | 32°F 1993 | |
| Sep 21 | 71°F | 41°F | 77°F 1999 | 31°F 1977 | |
| Sep 22 | 71°F | 41°F | 78°F 1947 | 30°F 1984 | |
| Sep 23 | 70°F | 40°F | 82°F 1952 | 30°F 1948 | |
| Sep 24 | 70°F | 40°F | 80°F 1952 | 30°F 1970 | |
| Sep 25 | 69°F | 40°F | 79°F 1952 | 30°F 1972 | |
| Sep 26 | 69°F | 40°F | 79°F 1991 | 29°F 1972 | |
| Sep 27 | 68°F | 39°F | 80°F 2022 | 26°F 1972 | |
| Sep 28 | 68°F | 39°F | 78°F 1963 | 29°F 1983 | |
| Sep 29 | 67°F | 39°F | 75°F 1993 | 28°F 1948 | |
| Sep 30 | 67°F | 38°F | 76°F 1987 | 30°F 2019 |
Chance of rain
Sunrise and sunset
Times for 2026, local time (PDT).
- September 1
- sunrise 6:23 AM, sunset 7:44 PM
- September 30
- sunrise 7:02 AM, sunset 6:45 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00451504 (Cle Elum), public domain. Records: NOAA GHCN-Daily, station USW00024237, 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.