September weather in Medical Lake, WA
The average temperature in Medical Lake in September is 58.2°F (42.9°F–73.4°F). Average precipitation: 0.61 inches.
September is a fall month in Medical Lake, and is warmer than the annual average of 46.4°F. Daily temperatures swing about 30.5°F between overnight low and afternoon high. Expect about 5 days with precipitation. Daylight averages about 12h 19m. For travel, September is a comfortable month to visit.
Avg High
73.4°F
Avg Low
42.9°F
Precipitation
0.61 in
Snow
0.1 in
September records in Medical Lake
| Date | Record High | Record Low | Record Precip |
|---|---|---|---|
| September 1 | 99.0°F (2025) | 34.0°F (2008) | 0.01 in (2023) |
| September 2 | 100.0°F (2025) | 37.9°F (1999) | 0.14 in (2000) |
| September 3 | 99.0°F (2025) | 37.0°F (2004) | 0.12 in (1997) |
| September 4 | 93.0°F (2003) | 32.0°F (2015) | 0.21 in (2000) |
| September 5 | 93.0°F (1998) | 35.1°F (2005) | 0.40 in (2015) |
| September 6 | 93.9°F (1998) | 34.0°F (2010) | 0.15 in (2009) |
| September 7 | 95.0°F (2024) | 30.9°F (1999) | 0.15 in (2003) |
| September 8 | 91.0°F (2011) | 30.9°F (2020) | 0.72 in (2003) |
| September 9 | 91.9°F (2011) | 30.9°F (2020) | 0.67 in (2019) |
| September 10 | 91.9°F (2011) | 37.9°F (1998) | 0.37 in (2000) |
| September 11 | 93.0°F (2011) | 28.9°F (2012) | 0.43 in (2004) |
| September 12 | 91.0°F (2002) | 28.0°F (2014) | 0.10 in (2005) |
| September 13 | 91.0°F (2013) | 28.9°F (2016) | 0.08 in (2004) |
| September 14 | 91.0°F (2002) | 30.9°F (2016) | 0.26 in (2025) |
| September 15 | 91.9°F (1998) | 33.1°F (2006) | 0.19 in (2004) |
| September 16 | 91.9°F (2009) | 32.0°F (2006) | 0.17 in (1997) |
| September 17 | 88.0°F (2008) | 28.9°F (1996) | 0.24 in (2002) |
| September 18 | 86.0°F (2008) | 30.0°F (2018) | 0.34 in (2019) |
| September 19 | 87.1°F (2008) | 33.1°F (2018) | 0.46 in (2010) |
| September 20 | 84.9°F (2012) | 30.9°F (2007) | 0.20 in (2006) |
| September 21 | 87.1°F (1999) | 28.9°F (1996) | 0.33 in (2017) |
| September 22 | 86.0°F (1999) | 26.1°F (1996) | 0.09 in (2013) |
| September 23 | 89.1°F (2009) | 19.0°F (2000) | 0.24 in (2020) |
| September 24 | 89.1°F (2011) | 0.0°F (2012) | 0.13 in (2013) |
| September 25 | 86.0°F (1997) | 28.9°F (1996) | 0.17 in (2020) |
| September 26 | 82.9°F (2003) | 28.9°F (1999) | 0.10 in (2023) |
| September 27 | 88.0°F (2022) | 25.0°F (1999) | 0.48 in (2021) |
| September 28 | 84.0°F (2024) | 24.1°F (1999) | 0.73 in (2019) |
| September 29 | 81.0°F (2006) | 30.9°F (2007) | 0.38 in (2022) |
| September 30 | 79.0°F (2008) | 26.1°F (2024) | 0.49 in (2005) |