Canada has recorded its highest ever temperature as the country's west and the US Pacific north-west frazzle in an unprecedented heatwave. Lytton in British Columbia soared to 46.6C (116F) on June 27, breaking an 84-year-old record. A "heat dome”, static high pressure acting like a lid on a cooking pot, has set records in many other areas. The US and Canada have both warned citizens of "dangerous" heat levels that could persist this week. Reportedly, climate change is expected to increase the frequency of extreme weather events, such as heatwaves. BBC forecaster Nick Miller says that "heat dome" isn't a strictly defined meteorological term but has become associated with describing large areas of high pressure, leading to clear skies and hot sunny days. Environment Canada said Alberta, and parts of Saskatchewan, Yukon and the Northwest Territories, should also be on alert. In its warning, it forecast a "prolonged, dangerous, and historic heatwave will persist through this week", with temperatures 10C-15C above normal, at near 40C in many places, reported BBC. Watch the video to know more.