Climate Insights for Järna

The climate in Järna is cool. The average annual temperature is 5°C and approximately 747mm of precipitation falls per year. Järna receives a notable amount of rainfall throughout the year, including during its driest month. Järna is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, June, August. The coldest months are January, February, December, when temperatures can drop to -7°C. Snowfall occurs from January to December, with around 143cm accumulating over the season.

Temperatures in Järna vary considerably across the year, with a 27°C difference between the coldest and warmest months. July is the warmest month, though highs remain moderate at 20°C with a mean of 16°C. The coldest month is January, when overnight lows fall to -7°C and the daily average is -4°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows. The sharpest temperature change occurs between April and May, with a 6°C shift in average temperatures.

Järna is a relatively dry area, receiving approximately 747mm of precipitation annually, which averages out to around 62mm per month. The wettest month is July, averaging 113mm of rainfall. August and May also tend to see above-average precipitation. The driest month is February, with just 38mm. That's 74mm less than July, the wettest month. Precipitation varies noticeably between seasons, with the second half (July to December) of the year generally seeing more rainfall. Snowfall is a regular feature from January to December, with around 143cm accumulating over the season. January typically sees the most snow at around 34cm.

Järna is mildly breezy, with an average annual wind speed of 16km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 18km/h, though still comfortable for most outdoor activities. The calmest conditions occur in July, with average winds dropping to 14km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 4km/h between the calmest and windiest months. Wind tends to be stronger during winter months, driven by seasonal pressure systems. The seasonal averages break down to 17km/h in winter, 16km/h in spring, 15km/h in summer, 16km/h in autumn.

It is currently spring in Järna, which began on March 20, 2026. Järna is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in July at around 20°C, while the coldest stretch bottoms out in January near -7°C. Summer is next, beginning on June 21, 2026 — 89 days from now.

The table below shows monthly climate averages for Järna based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.