Olsztyn Weather in September
Average highs run from 21°C on September 1 to 16°C on September 30, and lows from 11°C to 7°C. Normal precipitation for the month is 57 mm over about 12 wet days.
September day by day
The normal high and low for each date, in °C.
- Normal low
- Normal high
- Reanalysis extreme high
- Reanalysis extreme low
September at a glance
- Average high
- 18°C
- Average low
- 9°C
- Precipitation
- 57 mm
- Reanalysis high
- 34°CSep 1, 2015
- Reanalysis low
- -1°CSep 30, 1993
- Daylight
- 13 h 43 min to 11 h 39 min
- Cloud cover
- 64%
- Humidity
- 78%
- Dew point
- 9°C
- Wind
- 15.5 km/h
Every day of the month
A wet day has at least 1 mm of precipitation in the reanalysis.
| Date | Normal high | Normal low | Reanalysis high | Reanalysis low | Chance wet |
|---|---|---|---|---|---|
| Sep 1 | 21°C | 11°C | 34°C 2015 | 4°C 2008 | 43% |
| Sep 2 | 20°C | 11°C | 25°C 1996 | 5°C 2003 | 43% |
| Sep 3 | 20°C | 11°C | 26°C 2008 | 3°C 2003 | 43% |
| Sep 4 | 20°C | 11°C | 26°C 2002 | 6°C 2010 | 43% |
| Sep 5 | 20°C | 10°C | 28°C 2002 | 5°C 2010 | 43% |
| Sep 6 | 20°C | 10°C | 27°C 2008 | 4°C 1993 | 42% |
| Sep 7 | 20°C | 10°C | 27°C 2008 | 6°C 1991 | 41% |
| Sep 8 | 20°C | 10°C | 26°C 2005 | 5°C 1993 | 42% |
| Sep 9 | 19°C | 10°C | 27°C 2005 | 6°C 2004 | 41% |
| Sep 10 | 19°C | 10°C | 27°C 2005 | 5°C 2004 | 41% |
| Sep 11 | 19°C | 10°C | 28°C 2012 | 5°C 1996 | 40% |
| Sep 12 | 19°C | 9°C | 27°C 2016 | 4°C 1996 | 38% |
| Sep 13 | 19°C | 9°C | 26°C 2014 | 4°C 1991 | 36% |
| Sep 14 | 18°C | 9°C | 25°C 2014 | 4°C 2008 | 35% |
| Sep 15 | 18°C | 9°C | 27°C 2020 | 5°C 2008 | 35% |
| Sep 16 | 18°C | 9°C | 27°C 2020 | 5°C 1999 | 35% |
| Sep 17 | 18°C | 9°C | 29°C 2015 | 4°C 2000 | 34% |
| Sep 18 | 18°C | 8°C | 25°C 2018 | 1°C 2000 | 31% |
| Sep 19 | 18°C | 8°C | 27°C 2018 | 2°C 1995 | 30% |
| Sep 20 | 18°C | 8°C | 28°C 2018 | 4°C 1996 | 30% |
| Sep 21 | 17°C | 8°C | 27°C 2003 | 1°C 1996 | 30% |
| Sep 22 | 17°C | 8°C | 24°C 2020 | 0°C 1996 | 31% |
| Sep 23 | 17°C | 8°C | 25°C 2003 | 1°C 2000 | 30% |
| Sep 24 | 17°C | 7°C | 24°C 2020 | 0°C 2000 | 30% |
| Sep 25 | 17°C | 7°C | 24°C 2006 | 0°C 2000 | 31% |
| Sep 26 | 17°C | 7°C | 25°C 2020 | 1°C 2001 | 32% |
| Sep 27 | 16°C | 7°C | 23°C 2006 | 1°C 2001 | 33% |
| Sep 28 | 16°C | 7°C | 21°C 1999 | 1°C 2002 | 34% |
| Sep 29 | 16°C | 7°C | 22°C 2016 | -1°C 1993 | 34% |
| Sep 30 | 16°C | 7°C | 23°C 1991 | -1°C 1993 | 34% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (GMT+2).
- September 1
- sunrise 5:46 AM, sunset 7:29 PM
- September 30
- sunrise 6:38 AM, sunset 6:17 PM
Other months
Sources
Cloud, humidity, wind and sunshine, and temperature and precipitation: 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 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus.