The Thompson Okanagan region enjoys a continental climate.
Seasons here are more pronounced than on the coast. Summers tend to be warmer and drier, while winters are colder but with far less precipitation. Thanks to this climate and a vast array of mountains and lakes, the Thompson Okanagan has become both a summer and winter holiday playground.
As you can see from the charts, precipitation, as well as high and low temperatures, can vary considerably within the Thompson Okanagan. These two charts are most indicative of the weather within the region. Kelowna is situated in the region's sunny Okanagan Valley; Mount Robson is the highest peak in the Canadian Rockies and found in the northern Thompson Okanagan.
Four key holiday destinations – Penticton, Kelowna, Vernon and Kamloops – lie on the southern portion of BC's Interior Plateau, picturesquely located amongst grassy hills, rolling vineyards and large, sand-bordered lakes. The area receives hundreds of hours of sunshine all year long with very little precipitation. Kamloops, for example, has an average maximum temperature of -1°C in January and 28°C in July, with just 279 mm of annual precipitation.
Further north, the region becomes increasingly mountainous, with more precipitation and cooler annual temperatures. Blue River in the Columbia Mountains has an average maximum of just -5°C in January and 24°C in July and receives nearly four times as much annual precipitation as Kamloops.
Temperatures warm up rapidly in the region, with April daytime highs reaching 20°C in the Okanagan Valley.
The Okanagan, Similkameen and Thompson river valleys experience BC's hottest summers, with temperatures often in the 30s °C, occasionally rising above 40°C. Temperatures are cooler further north in the high mountain ranges, with average daily highs in the low 20s °C.
By late October, average daily highs range from 8-13°C, with lows reaching freezing. In December, communities in the southern half of the region have average daytime highs just above freezing.
During the winter months most of the region's average daytime highs hover around near-freezing. Daytime lows of -10°C are common. The skiing is magnificent, with the region's mountains renowned for their dry, fluffy powder snow.
What to Wear
In late spring and throughout the summer, shorts and t-shirts are the norm but pack a sweater for cooler evenings. The lakes here are wonderful, warm and surrounded by sandy beaches so be sure to bring a bathing suit during the summer months. In the winter, you'll want to keep warm with a heavy coat or down jacket, gloves/mittens, scarf and hat.