Great Bear LakeMeteorological Information
Check out the weather in Deline - Great Bear Lakes only permanent settlement. Although this will give you an idea of what the weather is like around Great Bear, because of it's immense size - 12,000 square miles - it's not unusual for there to be several different weather systems hitting other parts of the lake at any one time.
Weather forecast for Great Bear Lake, Northwest Territories (Canada)
https://www.yr.no/place/Canada/Northwest_Territories/Great_Bear_Lake/