June Sanders, 73, was thinking of her dog when she decided Sunday to visit a Northeast Portland cooling center.

The heat can cause labored breathing, excessive salivation and distress for Rudy, her wiry greyhound that snoozed at her feet.

“I can get down to my skivvies,” she said. “He can’t.”

As Oregon entered the fourth day of sizzling temperatures Sunday, Portland recorded its first 100-degree day of the year and other parts of the state experienced another day of triple digits. Cooling centers continued operating in Multnomah, Washington and Clackamas counties, and weather forecasters predicted at least two more days of hazardous heat.

Fewer than 100 people on Saturday visited the three cooling centers that Multnomah County opened in Portland and Gresham amid the heat wave. On Sunday afternoon, the center that Sanders visited at Portland Covenant Church, 4046 N.E. Martin Luther King Jr. Blvd., had fewer than 10 people inside at one point.

Sanders said she’s noticed that not as many people are using the cooling center this year as in years past. She doesn’t think the issue is outreach — rather, issues in planning. She feels that the cooling centers should have been announced much sooner, she said.

Multnomah County officials announced the centers Thursday, when Portland’s high temperature reached 92 degrees. The county’s state of emergency started at noon Friday, when Portland’s high climbed to 99 degrees.

Most who visited the church’s cooling center Sunday afternoon appeared older, and some said they were trying to avoid triggering poor health conditions or escape a lack of air conditioning at home.

Do Good Multnomah — a nonprofit organization focused on housing — organized the center at the church, staff member Savannah Valentine said.

“The church supplies the space, then we get the supplies from the county and we staff it,” Valentine said.

Organizers said they expect to see more people attend as temperatures may rise Monday and Tuesday, possibly reaching 102 or 103 degrees.

The center was sparsely populated but had plentiful resources — clothes, food, shampoo and conditioner, among other items.

Sanders said she’s thankful to the church for opening its doors to the public, including on a day of worship. She said she wants others to feel welcome.

“This is a safe place to be,” Sanders said.

— Andrew Miller covers business news. Reach him at amiller@oregonian.com or 971-803-2954.

— David Nuñez covers breaking news and public safety for The Oregonian/OregonLive. Reach him at 503-294-7607 or dnunez@oregonian.com.