Winnipeg’s location in the Canadian Prairies gives it a warm-summer humid continental climate , with warm, humid summers, and long, severely cold winters. Summers have a July mean average of 19.7 °C (67.5 °F). Winters are the coldest and driest time of year, with the January mean average around −16.4 °C (2.5 °F) and total winter precipitation (December through February) averaging 55.2 mm (2.17 in). Temperatures occasionally drop below −40.0 °C (−40 °F).
On average there are 317.8 days per year with measurable sunshine, with July seeing the most on average. With 2353 hours of sunshine per year, Winnipeg is the second sunniest city in Canada. Total annual precipitation (both rain and snow) is just over 52 centimetres (20 in). Thunderstorms are very common during summer, and sometimes severe enough to produce tornadoes. Low wind chill values are a common occurrence in the local climate. The wind chill has gone down as low as −57 °C (−70.6 °F) and on average there are twelve days of the year that can reach a wind chill below −40 °C (−40 °F).
The highest temperature ever recorded in Winnipeg was 42.2 °C (108 °F) on 11 July 1936 while the highest daily low temperature was 28.3 °C (82.9 °F) on 12 July 1936. The apparent heat can be even more extreme due to bursts of humidity, and on 25 July 2007 a humidex reading of 47.3 °C (117.1 °F) was measured.
The frost-free season is comparatively long for a location with such severe winters. The last spring frost is on average around 23 May, whilst the first fall frost is on 22 September.