Climate averages 1991–2020
Joensuu weather
in September.
A cool, moderately wet month: the 4th warmest and the 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a cool month in Joensuu: daytime highs average 12.4°C and nights cool to about 8.8°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 68 mm of rain on roughly 12 days, which makes September a moderately wet month (the 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 03 min on an average September day.
The nearest other city in this atlas is Kuopio (111 km away). In September its highs average 12.6°C, about as warm as Joensuu, with 65 mm of rain.
Among the 13 cities listed in Finland, Joensuu ranks 12th of 13 for the warmest September highs and 13th of 13 for the driest September (rainfall, lowest first). The mean September high of those 13 cities is 13.8°C; Joensuu is 1.4°C cooler than that mean.
From September to October, average highs fall by 7.1°C to 5.2°C, and monthly rainfall falls from 68 mm to 63 mm.
The annual picture
September in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Joensuu climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -6.0°C-9.9°C | -9.9°C | 41 | 10.7 | 6.06 h |
| February | -6.4°C-10.2°C | -10.2°C | 35 | 9.5 | 8.79 h |
| March | -2.0°C-6.3°C | -6.3°C | 34 | 9.0 | 11.712 h |
| April | 3.9°C-2.0°C | -2.0°C | 32 | 7.9 | 14.815 h |
| May | 11.2°C4.4°C | 4.4°C | 49 | 9.3 | 17.818 h |
| June | 17.1°C11.5°C | 11.5°C | 75 | 12.7 | 19.820 h |
| July | 20.2°C14.9°C | 14.9°C | 85 | 12.7 | 18.919 h |
| August | 18.1°C13.6°C | 13.6°C | 82 | 13.2 | 16.116 h |
| September, selected | 12.4°C8.8°C | 8.8°C | 68 | 11.9 | 13.113 h |
| October | 5.2°C2.7°C | 2.7°C | 63 | 12.4 | 10.010 h |
| November | 0.0°C-2.6°C | -2.6°C | 55 | 11.6 | 7.07 h |
| December | -3.3°C-6.8°C | -6.8°C | 53 | 12.7 | 5.15 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Kuopio in SeptemberFinland · 111 kmHigh 12.6°C · Low 8.3°C · 65 mm rain
- Lappeenranta in SeptemberFinland · 190 kmHigh 13.9°C · Low 8.6°C · 56 mm rain
- Jyväskylä in SeptemberFinland · 212 kmHigh 13.2°C · Low 8.1°C · 54 mm rain
- Vyborg in SeptemberRussia · 217 kmHigh 14.2°C · Low 9.3°C · 59 mm rain
- Kouvola in SeptemberFinland · 251 kmHigh 14.2°C · Low 8.4°C · 53 mm rain
- Petrozavodsk in SeptemberRussia · 254 kmHigh 13.0°C · Low 8.6°C · 58 mm rain
- Lahti in SeptemberFinland · 281 kmHigh 14.1°C · Low 8.5°C · 51 mm rain
- Saint Petersburg in SeptemberRussia · 298 kmHigh 14.4°C · Low 9.1°C · 55 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Joensuu) is explained once on the Joensuu year overview and on the Sources, method and limits page.