(Radio Iowa) – Memorial Day weekend may be the unofficial start of summer, but the warm weather will arrive a week late this year. After high temperatures much of this week below normal in the 60s and 70s, meteorologist Dave Cousins, at the National Weather Service in Davenport, says a heat wave will start to roll in on Friday, with a steamy forecast for next week.

“There’s been this pesky storm system here that’s been lingering across the upper Midwest, which is why it’s been kind of cool and showers each day here the last week,” Cousins says. “That’s finally going to move off to the east later today, and as that does that, high pressure is going to build into the area and it will be noticeably warmer even by tomorrow.”

The forecast calls for much of Iowa to see highs Friday in the upper 70s and low 80s, with a gradual increase coming as the month of June nears. “It’s just a little bit warmer each day. Saturday’s in the mid 80s,” Cousins says, “and here in the Quad Cities, we do have 90 in the forecast on Monday and again on Tuesday.”

You may need to make adjustments to stay comfy. (Radio Iowa photo)

Some long-time residents say it’s just not Iowa unless you run both the heater and the air conditioner in your car the same week, sometimes on the same day. Along with the relatively abrupt changes in temperature comes the risk of severe weather, so Cousins reminds Iowans to be “weather aware.”

“There are chances next week for showers and storms nearly every day after Monday,” he says, “so keep an eye out for more active weather next week.” The first day of meteorological summer is June 1st, though the season won’t officially arrive until June 20th.