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Residents of Portland, Oregon, just want their daily routine — and temperatures — to return to normal.

Temperatures reached a high of 103 degrees on Wednesday, breaking a 31-year-old record for the day. The city’s old record was 96 degrees, which it marked on August 2, 1986.

And temperatures are expected to rise even higher through the rest of the week.

Some models show the city could reach or break its all-time high of 107 degrees (1965 and 1981) by Thursday.

Commuters on TriMet, the metro area’s public transit system, had longer waits because of network problems and slower rail speeds prompted by the high temps, according to CNN affiliate KATU-TV.

Some 15 million people in the Pacific Northwest are under excessive heat warnings and advisories. That creates “a dangerous situation in which heat illnesses are possible,” the National Weather Service said.

Late on Wednesday, Oregon Gov. Kate Brown declared a state of emergency saying the current “hot, dry and windy” conditions around the state are increasing the threat of wildfires.

Portland wasn’t alone: Seattle also broke a daily record. The city reached 90 degrees on Wednesday, breaking a record of 89 degrees from August 2, 2009.

CNN meteorologists said Seattle could see 100 degrees this week, which would be only the fourth time in recorded history. Other cities will likely see temperatures hit the triple digits.

Desperate times, desperate measures

The heat has settled in over a region where many homes don’t have air conditioning. Only one-third of Seattle residents have it, while Portland’s number is about 70%. Portions of Oregon are a good bit lower.

Related: Deadly heat waves to become more common

CNN affiliate KIRO in Seattle reported numerous cooling centers were open in the city.

Many Portland residents took to social media to document some of the strange and outrageous ways they are keeping cool, including sticking their feet in a cooler of ice.

One Portland library even started offering free water bottles to its patrons — with “no overdue fines!”

Jillian Henze, spokeswoman for the Seattle Hotel Association, said those without air conditioning who are seeking relief will find the supply of rooms scarce. “It is our busiest season of the year; we got cruise ships and summer travel, and rooms are booked up way in advance,” she said.

Because of thick smoke from British Columbia wildfires, temperatures overnight into Wednesday did not cool off much. Seattle’s low was 69 degrees; the normal reading is 57.

Northern California will likely see peak heat Wednesday, with slightly milder temperatures on Thursday.

Related: Hot car deaths reached record numbers in July

What’s causing this?

A ridge formed in the jet stream, forcing the stronger winds in the upper atmosphere well into Canada, allowing for clear skies in the Pacific Northwest and the temperatures to rise to extreme levels. Friday into the weekend, the jet stream will flatten, allowing for temperatures to ease near normal.

Until then, police and agencies are ensuring those most vulnerable receive help. Portland police on Tuesday tried to get people who normally live on the streets into shelters or cooling centers, CNN affiliate KPTV said.

“They really appreciate it because, literally, they are here, they don’t want to walk around because it’s hot out,” Officer Ryan Engweiler told the station. “Just by us driving around giving them the water, giving them the information.”