A record-clobbering, 240-day streak of temperatures above the freezing mark at the Medford airport was expected to end today.
The coldest temperatures of the autumn season are inbound to Jackson County, with nighttime lows into the mid-20s expected overnight through Saturday, said forecasters at the National Weather Service, which is based at the airport.
"It's going to cool down a lot," said meteorologist Misty Duncan.
Weather officials said the last time the temperature hit 32 degrees or less at the Medford airport was March 24. That's 240 days, the longest non-freezing period since the weather service started keeping Medford records in 1911.
The previous record was set last year, when the airport went 230 days — from March 23 to Nov. 9 — without freezing temperatures.
The cold spell is being driven by eastbound winds pushing a mass of cold, dry air into southwestern Oregon and northwestern California. The front is expected to hover over the region until Saturday morning.
"The air that's behind it is going to be really dry, and the winds that are behind it are going to make it even drier," Duncan said.
A nighttime low of 23 degrees is expected tonight and Friday. Across the Cascades, in the Klamath Basin and Lakeview areas, low temperatures will plummet to the teens or single digits. Weather officials said it should start to warm back up Sunday.
"For some areas in Jackson and Josephine counties, as well as much of Douglas County, this will be an unusually late and strong first freeze of the fall season," the National Weather Service said in a weather alert.
Prior to the cold snap, more than half an inch of rain fell in Medford over a 24-hour period, meteorologists said. More than 6 inches of new snow hit Crater Lake during the day Wednesday.
Weather officials urged people to take precautions. Make sure sensitive vegetation is covered, get pets inside and allow a bit of water to run through pipes so the freezing weather does not damage them.
"Make sure they're dripping. A little bit of running water will keep it from freezing over and busting the pipe," Duncan said. "Take precautions, do what you can."
Reach Mail Tribune reporter Ryan Pfeil at 541-776-4468 or email@example.com.