Heat warnings return for northern, central Alberta Just a week after a scorching heat wave engulfed Alberta, Environment Canada has again issued heat warnings for northern Alberta and parts of central Alberta. Social Sharing CBC News · Posted: Jul 07, 2021 4:44 PM MT | Last Updated: July 7 Temperatures reaching 29 C, combined with overnight lows near 14 C, are expected for the next three days, Environment Canada said Wednesday.(Nathan Gross/CBC) Just a week after a scorching heat wave engulfed Alberta, Environment Canada has again issued heat warnings for northern Alberta and parts of central Alberta. The latest period of high temperatures looks to be milder than the historic heat wave last week, but it still comes with an elevated risk of heat-related illness.