Monthly climate in Forssa, Finland

Last updated: July 31, 2025

Under the Köppen–Geiger climate classification Forssa features a humid continental climate (Dfb). Temperatures typically range between -4 °C (24 °F) and 17 °C (64 °F) through the year, but rarely can drop to -26 °C (-14 °F) or can rise to as high as 32 °C (90 °F). The average annual precipitation amounts to about 740 mm (29.1 inches) and receives 139 rainy days on the 1 mm (0.04 inches) threshold annually. Forssa enjoys an average of 3266 hours of sunshine throughout the year, and daylight varies from 5 hours 44 minutes to 19 hours 0 minutes per day.

Monthly average temperatures in Forssa, Finland

The warmest months in Forssa are June, July and August, with daily mean temperatures ranging from 16 to 17 °C (61 - 64 °F) throughout the day. The coldest temperatures usually occur in January, February and December, when daily mean temperatures range from -4 to -2 °C (24 - 29 °F) throughout the day. On average each year, Forssa experiences 15 days above 25 °C (77.0 °F) and 141 days below 0 °C (32.0 °F).

Monthly average temperatures with daily means, minimums and maximums for period, average high and low temperatures in Forssa. Generated using Copernicus Climate Change Service information. Data for period from January 2017 to June 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Maximum8°C
(46°F)
7°C
(45°F)
12°C
(54°F)
21°C
(69°F)
28°C
(82°F)
32°C
(89°F)
32°C
(90°F)
30°C
(87°F)
24°C
(76°F)
18°C
(64°F)
13°C
(55°F)
6°C
(43°F)
Mean maximum4°C
(40°F)
4°C
(40°F)
10°C
(51°F)
16°C
(61°F)
24°C
(76°F)
26°C
(79°F)
29°C
(84°F)
26°C
(79°F)
21°C
(71°F)
15°C
(59°F)
10°C
(51°F)
5°C
(41°F)
Average high-1°C
(30°F)
-2°C
(29°F)
2°C
(37°F)
8°C
(46°F)
15°C
(58°F)
21°C
(70°F)
22°C
(71°F)
20°C
(68°F)
15°C
(59°F)
9°C
(48°F)
4°C
(40°F)
-0°C
(32°F)
Daily mean-3°C
(26°F)
-4°C
(24°F)
-1°C
(30°F)
3°C
(38°F)
10°C
(50°F)
16°C
(61°F)
17°C
(64°F)
16°C
(61°F)
11°C
(52°F)
6°C
(43°F)
2°C
(36°F)
-2°C
(29°F)
Average low-6°C
(22°F)
-8°C
(19°F)
-5°C
(23°F)
-1°C
(30°F)
4°C
(39°F)
10°C
(51°F)
12°C
(54°F)
11°C
(52°F)
7°C
(45°F)
3°C
(38°F)
0°C
(33°F)
-4°C
(26°F)
Mean minimum-19°C
(-1°F)
-19°C
(-2°F)
-17°C
(2°F)
-10°C
(15°F)
-4°C
(25°F)
4°C
(40°F)
7°C
(44°F)
5°C
(42°F)
-0°C
(32°F)
-5°C
(23°F)
-7°C
(19°F)
-11°C
(13°F)
Minimum-26°C
(-14°F)
-25°C
(-13°F)
-26°C
(-14°F)
-14°C
(6°F)
-7°C
(21°F)
1°C
(34°F)
5°C
(41°F)
5°C
(41°F)
-4°C
(25°F)
-7°C
(19°F)
-10°C
(14°F)
-20°C
(-3°F)

Compare climate in Forssa with other places

Compare temperature, precipitation, sunshine, UV index in Forssa, Finland with other places around the world.

Monthly average precipitation in Forssa, Finland

Forssa usually has the most precipitation in July, August and October, with an average of 13 rainy days and 84 mm (3.3 inches) of precipitation per month. The driest months in Forssa are February, March and April. On average, 44 mm (1.7 inches) of precipitation falls during these months.

Monthly average precipitation and precipitation days in Forssa. Generated using Copernicus Climate Change Service information. Data for period from January 2017 to January 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Average precipitation mm (inches)50 (2.0)45 (1.8)46 (1.8)41 (1.6)60 (2.4)62 (2.4)87 (3.4)87 (3.4)63 (2.5)78 (3.1)53 (2.1)67 (2.6)
Average precipitation days (≥ 1 mm)1191111129111412151014

Monthly sunshine hours in Forssa, Finland

The sunniest months in Forssa are May, June and July, when the sun shines an average of 15 hours 21 minutes a day. Least sunny months in Forssa: January, November and December receive an average of 2 hours 19 minutes of sunshine daily.

Mean monthly sunshine duration, average sunshine hours per day and mean daily daylight hours in Forssa. Generated using Copernicus Atmosphere Monitoring Service information. Data for period from January 2017 to January 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Mean monthly sunshine hours5115226035144748847740628818010755
Mean daily daylight hours6h 35m9h 2m11h 51m14h 43m17h 24m19h 0m18h 8m15h 37m12h 49m9h 59m7h 18m5h 44m

Solar UV radiation in Forssa, Finland

Forssa experiences the highest level of ultraviolet (UV) radiation in June, July and August, when the maximum UV index can reach values of 5 - 7, which corresponds to the Moderate / High category of sun exposure. January, February and November are in the Low exposure category. In these months, the maximum values of the UV index do not exceed 1. For more detailed information, check out our hourly Forssa UV Index data.

Average daily maximum UV levels by month for Forssa. Generated using Copernicus Atmosphere Monitoring Service information. Data for period from January 2022 to January 2023.
 JanFebMarAprMayJunJulAugSepOctNovDec
UV Index (month maximum)113457754211