PORTLAND, Ore. -- It may be cooling down a tad, but meteorologists warn that everyone should still expect a scorching-hot weekend.

"We're headed toward 100 again Saturday, and that would be the first time we've had three straight triple digits days since July 1994. Afternoon clouds from thunderstorms may keep us just below 100," said KGW Chief Meteorologist Matt Zaffino. "The, after a hot Saturday with more sun, Sunday will be partly cloudy to mostly sunny with highs in the low 90s and a better chance for afternoon thunderstorms."

“You’d have to go back to the summer of 1981 to find a stretch like this,” added KGW Meteorologist Dave Salesky. “We’re going to see three days in a row of temperatures at over above 100 degrees.”

It was expected to be the longest hot streak of the summer so far and it started on Thursday when temperatures climbed to 102; a record for Portland. Friday was expected to break records at 100, too. the previous record was 98 degrees, set way back in 1967.

The National Weather Service issued an Excessive Heat warning for the area, and urged people to bewarse of heat-related illnesses. A Red Flag warning was put in effect from 12 p.m. Thursday to 9 a.m. Saturday for the Cascades, Mt. Hood and Siuslaw forests. That means fuel is very dry and the hot conditions create an extreme fire danger.

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Conditions will change next week, though.

"Much cooler weather blows in late Sunday night with showers and highs in the 70s on Monday. Cool weather will continue until Friday when we reach 80? with sunshine," Zaffino said.

Average temps for this time of year in the Portland Metro area are about 80 dgrees. Across the region, the heat was relentless. "I think a lot of records are going to fall," Salesky added. "From Seattle to Medford new daytime highs are possible. Overnight lows will only drop into the upper 60s. New record overnight low-high temperatures are also possible."

In Vancouver, cooling centers were opened to help area residents deal with the heat. They are located at Luepke Senior Center and Marshall Community Center, at 1009 E. McLoughlin and Firstenburg Community Center at 700 N.E. 136th Ave. until 10 p.m., then 5:30 a.m. to 9 p.m., Friday, Aug. 15 from 7 a.m. to 8 p.m., Saturday, Aug. 16.

The forecast for significant warming and drying with 90 and 100 degree temps will combine with heavy lightning for a bigger fire threat.

Helicopters have taken crews into the Mount Hood Wilderness to set up camp near a 270-acre wildfire, and crews report progress against a blaze that had given them problems.

The regional dispatching agency said Tuesday that setting up a small "spike camp" near the Gnarl Ridge fire means firefighters don't have to make three-hour hikes over mountainous and wet terrain just to get into position to do their work.

KGW graphic

The firefighters say they're concerned about warming temperatures expected in the region in the next few days and about what one official called "squirrelly winds" flowing around Mount Hood.

Fire officials said Tuesday morning a few isolated thunderstorms in the Oregon Cascades and eastern Oregon could pop up by evening.