Temperatures are forecast to skyrocket into at least the mid- to upper 100s this coming weekend.

PMG FILE PHOTO - Veronica and Peter Choruby check out the water fountains at West Linn's Hammerle Park during a heat wave in 2016.The Portland area is expected to face high temperatures that could set new all-time records this weekend.

With the mercury on the rise, Tualatin Valley Fire & Rescue and other local agencies are urging area residents to make a plan to keep cool — and to check on neighbors and relatives who may be vulnerable to the heat.

Friday's high in Hillsboro is 94 degrees, with a low of 65, but temperatures are expected to climb to 106 degrees on Saturday, June 26, and 111 degrees on Sunday, according to the National Weather Service.

Monday's expected high is 104 degrees. Temperatures will fall back into the mid-90s on Tuesday and later in the week, meteorologists predict.

The National Weather Service said Wednesday that weekend high temperatures will run 20 to 30 degrees above normal for late June, which could break records and put northwest Oregonians at an increased risk of heat-related illness.

"The high daytime temperatures, combined with warm overnight lows, will result in high heat risk and heat related stress," a heat advisory from NWS states. "Daily high temperature records will likely be broken. There is a chance to break the all time June high temperature records for a few locations."

TVF&R and other Washington County fire agencies enacted a high fire danger burn ban earlier this week, which will remain in effect at least into next week.

Cassandra Ulven, public affairs chief for TVF&R, says people should be aware of both the elevated fire risk and the risk of heat-related illness.

"I think we're all still experiencing collective fear and worry after last year's season," said Ulven, referring to last September's spate of wildfires. The month was Oregon's worst ever recorded for fires, with more than 1 million acres burning in September alone.

TVF&R is making preparations for the triple-digit heat.

"We are staffing up so that we have additional firefighters and paramedics on duty," Ulven said.

Additionally, Ulven is encouraging people to check in on neighbors and relatives who may be especially vulnerable. Not all homes in Washington County and other areas served by TVF&R on Portland's Westside have air conditioning, and older adults are especially prone to being affected by intense heat.

The U.S. Centers for Disease Control and Prevention reports more than 700 people die each year from extreme heat, with people age 65 and older at increased risk of heat-related illness or death.

What to do:

• Limit outdoor activities

• Never leave young children or pets unattended in vehicles under any circumstances.

• Pavement and asphalt may be dangerous to dogs' paws. Limit walks and exercise to morning or evening hours.

• Drink more water than usual and don't wait until you're thirsty to hydrate.

• Stay in air-conditioned buildings if possible and don't rely on fans as your only cooling device in extreme heat.

• Avoid using the stove or oven to cook — it will make you and your house hotter.

TVF&R is asking area residents to be familiar with signs of heat-related illness.

The CDC says symptoms of heat stroke can include:

• Elevated body temperature (103 degrees or higher)

• Hot, red, dry or damp skin

• Fast, strong pulse

• Headache

• Dizziness

• Nausea

• Confusion

• Loss of consciousness

In addition, heat exhaustion can have the following symptoms:

• Heavy sweating

• Cold, pale and clammy skin

• Fast, weak pulse

• Nausea or vomiting

• Muscle cramps

• Tiredness or weakness

• Dizziness

• Headache

• Fainting

If you or someone you know is experiencing signs of heat stroke, call 9-1-1. Symptoms of heat stroke may be alleviated by moving to a cooler place, applying cool cloths or bathing in cool water.

Heat exhaustion may be prevented or alleviated the same way. Sipping water may also help to ward off heat exhaustion. You should seek medical attention immediately if you or someone in your care begins throwing up or experiencing worsening symptoms, or if symptoms last for longer than an hour.

TVF&R also advises that people limit physical activity and spending time outdoors during extreme temperatures.

Meanwhile, the risk of wildfires is elevated during periods of hot, dry weather. TVF&R and other local agencies have been preparing for fire season as well. TVF&R has already deployed seven firefighters for pre-staging in Redmond, Ulven said, where they will be ready to assist with wildfires through at least June 27.

Editor's note: This story has been updated as of 5:30 p.m. June 23 with the latest forecast.

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