PORTLAND, Ore. (KOIN) — Red flag warnings have been issued for almost all of Western Oregon and Washington from Sept. 9 to Sept. 10., as low humidity, 90-degree temperatures and 40-mph winds are expected to worsen wildfire conditions in the Pacific Northwest.

“One of the biggest concerns we have is a combination of high winds and these types of dry conditions,” said Teddy Mayes with Portland Fire and Rescue.

KOIN 6 Meteorologist Kelley Bayern said that fire danger will remain a serious concern through Saturday night.

“Weather conditions set the stage for a potentially disastrous weekend here in the Pacific Northwest,” Bayern said. “Fire danger will remain high as a thermal trough drives strong easterly winds through the region. This is a classic easterly wind event. We see this pattern set up in the winter frequently. But during this time of year, with our dry weather and added heat, it spells out high fire danger.”

The expansive red flag warnings span the length of the Cascade Range and run west across most of Oregon and Washington. The few areas to avoid the warnings include the western half of Coos County, all but the eastern edge of Curry County, and areas of Washington bordering the Strait of Juan de Fuca.

A fire weather watch was issued for parts of central Oregon and Washington, east of the Cascades; however, many of those fire weather watches were later turned into red flag warnings. The full list is below.

Oregon counties in a red flag warning

  • Clatsop
  • Columbia
  • Multnomah
  • Clackamas
  • Hood River
  • Marion
  • Polk
  • Washington
  • Yamhill
  • Tillamook
  • Lincoln
  • Benton
  • Linn
  • Lane
  • Wasco
  • Sherman
  • Majority of Gilliam
  • Majority of Jefferson
  • Majority of Douglas
  • Majority of Jackson
  • Majority of Josephine
  • Majority of Curry
  • Majority of Jefferson
  • Some of Coos
  • Some of Klamath
  • Some of Deschutes
  • Some of Morrow
  • Some of Klamath

Washington counties under a red flag warning

  • Clark
  • Cowlitz
  • Skamania
  • Wahkiakum
  • Pacific
  • Lewis
  • Thurston
  • Pierce
  • Grays Harbor
  • Kitsap
  • Mason
  • Most of Klickitat
  • Most of Yakima
  • Most of Kittitas
  • Most of Jefferson
  • Most of Clallam
  • Most of King
  • Most of Snohomish
  • Most of Skagit
  • Most of Whatcom

Washington counties under a fire weather watch

  • Part of Okanogan
  • Most of Douglas

The red flag warning begins at midnight and will last through 11 p.m. Saturday. The Willamette Valley can expect 35 to 40-mph winds as early as Friday afternoon. In response to the alert, Portland Fire and Rescue is reminding residents to be especially cautious about fire danger for the next few days.

KOIN 7-day forecast.

“Fully extinguish cooking fires, do not park vehicles in tall grass, and avoid using power equipment that could ignite vegetation,” PFR said. “Reminder: A burn ban is still in effect in Multnomah County. Stay safe this weekend!”