Climate averages 1991–2020
Sumy weather
in September.
A mild, moderately wet month: the 5th warmest and the 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Sumy: daytime highs average 18.5°C and nights cool to about 10.1°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 51 mm of rain on roughly 8 days, which makes September a moderately wet month (the 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 42 min on an average September day.
The nearest other city in this atlas is Konotop (117 km away). In September its highs average 18.4°C, about as warm as Sumy, with 52 mm of rain.
Among the 59 cities listed in Ukraine, Sumy ranks 47th of 59 for the warmest September highs and joint 35th of 59 for the driest September (rainfall, lowest first). The mean September high of those 59 cities is 20.1°C; Sumy is 1.6°C cooler than that mean.
From September to October, average highs fall by 7.4°C to 11.1°C, and monthly rainfall falls from 51 mm to 50 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
Sumy climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -3.0°C-7.5°C | -7.5°C | 42 | 9.9 | 8.58 h |
| February | -1.9°C-7.8°C | -7.8°C | 35 | 8.9 | 10.010 h |
| March | 4.0°C-3.7°C | -3.7°C | 42 | 9.6 | 11.812 h |
| April | 13.2°C3.3°C | 3.3°C | 43 | 9.3 | 13.814 h |
| May | 19.5°C9.5°C | 9.5°C | 61 | 11.3 | 15.516 h |
| June | 23.2°C13.7°C | 13.7°C | 67 | 11.0 | 16.416 h |
| July | 25.2°C15.9°C | 15.9°C | 73 | 11.2 | 16.016 h |
| August | 24.6°C15.0°C | 15.0°C | 47 | 7.6 | 14.615 h |
| September, selected | 18.5°C10.1°C | 10.1°C | 51 | 8.2 | 12.713 h |
| October | 11.1°C4.4°C | 4.4°C | 50 | 8.8 | 10.811 h |
| November | 3.4°C-1.1°C | -1.1°C | 41 | 8.1 | 9.09 h |
| December | -1.4°C-5.6°C | -5.6°C | 40 | 9.2 | 8.08 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
- Konotop in SeptemberUkraine · 117 kmHigh 18.4°C · Low 10.2°C · 52 mm rain
- Belgorod in SeptemberRussia · 130 kmHigh 18.9°C · Low 10.4°C · 46 mm rain
- Kursk in SeptemberRussia · 132 kmHigh 17.9°C · Low 9.7°C · 54 mm rain
- Shostka in SeptemberUkraine · 140 kmHigh 17.6°C · Low 9.8°C · 52 mm rain
- Kharkiv in SeptemberUkraine · 146 kmHigh 19.6°C · Low 10.8°C · 45 mm rain
- Poltava in SeptemberUkraine · 149 kmHigh 19.6°C · Low 11.0°C · 47 mm rain
- Zheleznogorsk (Kursk Oblast), Russia in SeptemberRussia · 163 kmHigh 17.4°C · Low 9.7°C · 55 mm rain
- Gubkin in SeptemberRussia · 195 kmHigh 18.5°C · Low 10.1°C · 49 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 Sumy) is explained once on the Sumy year overview and on the Sources, method and limits page.