Residents should prepare for a heat wave in the coming days.
Temperatures are expected to reach 100 degrees or higher in parts of Southern Oregon and Northern California this weekend.
"It's really just kind of our first taste of summer coming our way," said Misty Firmin, a meteorologist with the National Weather Service in Medford. "We'll be pretty close, if not into, the triple digits for the valleys here."
Firmin said people should be especially careful when swimming because cold-water shock can be dangerous, even during hot weather.
The hot, dry conditions are also increasing the risk of heat-related illness. Forecasters are urging residents to stay hydrated and limit strenuous outdoor activity during the hottest parts of the day.
Firmin said the region typically sees temperatures above 100 degrees later in July and August.
"It's a little early," she said, "but it's not unusual for it to happen."
With the hot, dry weather, wildfires are also a concern. The fire danger in Jackson and Josephine Counties increases to moderate on Thursday.
There are a variety of advisories and warnings in effect on the coast, including a hazardous seas warning and small craft advisory.
Farther south, temperatures are expected to hit triple digits in Red Bluff and Redding from Thursday through Tuesday.
"We always like to remind people to make sure they don't leave pets or even children in the car with the windows shut for any amount of time," said Matthew Kidwell, a lead meteorologist at the National Weather Service in Eureka. "The temperature can really rise quickly and cause big problems."
There’s a heat advisory in effect Thursday through Saturday in areas of Shasta and Tehama County, as well as a red flag warning until Thursday evening. That means a higher potential for the rapid spread of fire, so residents should take precautions.
The maximum heat risk in Del Norte, Humboldt and Trinity Counties will be from Friday through the weekend.
Kidwell expects temperatures to cool down a bit later next week.
