PORTLAND, Ore. -- After several days of 90-degree-plus weather metro Portland could expect a little cooler afternoon Sunday, with highs forecast in the upper 80s.

Temperatures rose above 90 four straight days and through the Fourth of July.

Temperatures hit 96 degrees on Thursday. KGW Meteorologist Joe Donovan said the area could expect two more days of 90-degree weather before slightly cooler temperatures on Sunday, and more normal 70-degree weather for next week.

 Slideshow: Portlanders-Fun in the sun

A heat advisory was issued for the Willamette Valley, the coast range, the Gorge and SW Washington. And forecasters said the heat would continue into the holiday weekend.

More: KGW Weather Blog | NWS: Heat alert

Holiday Weekend

The heat could be a mixed blessing for big Fourth of July events like the Waterfront Blues Festival. The Blues Festival runs through Sunday on the Portland waterfront.

 Details: Blues Fest schedule | 4th of July Events

Pet safety

The Oregon Humane Society has tips for pet safety during the heat and the Fourth of July fireworks.

River patrols up

As temperatures soared into the 80's on Wednesday, Clackamas County Marine Sgt. Steve Thouroughman was a busy man.

He spent the day cruising the Clackamas River, asking boaters to show him their life jackets and a whistle-- both requirements on the water.

 Slideshow: Fun in the sun

For those without whistles, Thouroughman had extras. As for common sense, he said folks on the water need to bring their own, and plenty of it.

"People do lose some of their inhibitions when it's hot," said Thouroughman. "When you combine that with alcohol, it gets even more dangerous," he said.

 Link: Portland pools open

At High Rocks Park along the Clackamas River, dozens of sun and thrill seekers jumped off the rocks including 19-year-old Ashlin Kneeland.

"I'm scared of hights, so when I first jump off it's kind of scary, but it's still pretty fun," Kneeland said. He added that landing in the cold, Clackamas River is exhilaration enough without the fancy stunts. "I think they're kind of crazy, because people have died out here before, so I wouldn't want to do that," said Kneeland.

"They definitely get our hearts going with some of the tricks they do off these rocks," said AMR life guard, Emily VanMeter. She said nothing dries up common sense faster than alcohol, which is illegal at the park.

This weekend the Clackamas County will fill the Clackamas and Willamette rivers the water with extra patrols, especially near High Rocks, to give VanMeter a hand.

"It's great to see these guys patrolling up and down, because unfortunately we do get a lot of drinking and a rowdy crowd here," said VanMeter.

Thouroughman added that Clackamas County's Marine Patrol will get a hand from other agencies to handle the holiday and hot-weather crowds.

"We encourage them to enjoy the water, but we want them to enjoy it safely," he said.

 More: River safety