A two-day period of triple-digit temperatures kicks off today.
The National Weather Service has issued a heat advisory because of the spike in heat, starting at 11 a.m. today and running through 11 p.m. Tuesday. Weather officials predict high temperatures of 103 and 105 degrees, respectively.
There won't be much of a reprieve from the heat Wednesday or Thursday, either, with temperatures reaching up to 99 and 96 degrees, respectively. "(That's) not heat advisory territory for us, but still hot," NWS meteorologist Ryan Sandler said.
Temperatures could vary slightly around the Rogue Valley because of microclimates.
Those predicted highs won't break or tie any records, but they'll be close. Medford's July 1 temperature to beat reached 108 degrees in 1942. The July 2 record is also 108, set in 1922.
Overnight, low temperatures will drop down to about the mid-60s, weather officials said in the heat advisory issued today. A heat advisory is issued during extended periods of hot weather where temperatures reach at least 103 degrees during the day and don't drop below 65 degrees during the night. During that time, conditions like heat exhaustion and heat stroke are possible.
The advisory is in effect for Jackson, Josephine and Modoc counties, with north central and southeast Siskiyou County and eastern Curry County included.
A slight chance of thunderstorms is also predicted Tuesday through Thursday because of some monsoon moisture that's pushing up through California.
"A few could sneak over the Siskiyous and into the valley," Sandler said.
The high temperatures are part of a heat wave affecting much of the western United States, centered over the Four Corners region.
"Think of it as a huge bubble of heat, and the high pressure is the center of the bubble," he said. "It's a huge area of high pressure, and it covers most of the western United States from the Rockies west."
Weather officials are encouraging Rogue Valley residents to beat the heat by staying out of the sun during the afternoon hours and drinking plenty of water.
"The main thing is just staying out of the sun and not exerting," Sandler said.
— Ryan Pfeil