Southwestern Saskatchewan is expected to be blasted with its first heat wave of the summer this week.

Swift Current is projected to receive seven straight days of scorching temperatures with daytime highs of at least 30 C, a mark the city has only experienced once this year - on June 23 at 30.8 C.

The toasty forecasted weather the southwest and prairies will see is being created by a ridge of high pressure.

"The core or epicentre of the heat is located further south over northern California, it is expanding north and east," said Environment and Climate Change Canada meteorologist Jennifer Smith. "High pressure causes air to sink and dry out, reducing cloud cover and leading to hot temperatures."

Meteorologists and health officials are worried with overnight temperatures across western Canada expected to be in the middle to high teens.

"This will exacerbate health risks since it will deprive people without access to cooling of the chance for temporary relief," she said. "Relatively cooler temperatures can be found near the water and at higher levels in the mountains. These may be options, depending on where one lives."

Heat illnesses can affect a wide range of people, but Health Canada's Peter Berry said older adults, indigenous people, infants and young children, and people with chronic illness are at a greater risk. The chronic illnesses he outlined include diabetes, mental health, and cardiovascular, or lung disease.

"Being prepared for hot weather, being able to identify the symptoms of heat illness and knowing what to do to cool down are critical steps all people in Canada should know to protect themselves and their loved ones," Berry said.

Health Canada has a three-step guide to help individuals stay safe during extremely warm temperatures. Staying up to date with the latest weather forecasts and alerts, keeping hydrated, and staying cool.