11/23/2023 0 Comments Oregon winter scenerySnowfall in Oregon is greatest in the Cascade Range. Snow The heaviest snowfalls in Oregon occur in the Cascade Range. Statewide, the dry months are July and August, when moisture arrives during afternoon thunderstorms, mainly in the mountains, and less often from storms that reach the north coast and adjacent counties. Precipitation is less in the months between winter and summer: April through June in the spring and September and October in the fall. Īcross Oregon, the wet season runs from November through March, when the jet stream is strongest in the Northern Hemisphere. Exceptions occur at higher elevations in the Blue Mountains and the Wallowa Mountains to the northeast, which get 50 to 80 inches (1,300 to 2,000 mm) a year. The remaining two-thirds of the state is relatively dry, classified as semi-arid, with large areas receiving no more than 12 inches (300 mm) a year. Since volcanic peaks in the range are quite high-more than 11,000 feet (3,400 m) in the case of Mount Hood -most of the remaining Pacific moisture falls here in the form of rain or snow. East of the valley, the storm air rises again as it meets the Cascade Range, cooling once more and forming condensate at elevations often as low as 3,000 feet (910 m). In the Willamette Valley east of the Coast Range, storms "blowing" from the Pacific retain enough moisture to drop from 35 to 45 inches (890 to 1,140 mm) annually in the most heavily populated part of the state. At lower elevations along the coast, orographic precipitation is less intense but still produces 60 to 80 inches (1,500 to 2,000 mm) a year. The heaviest precipitation in the state occurs at 2,000 to 4,000 feet (610 to 1,220 m) above sea level in these coastal mountains. As humid ocean air flows east from the ocean and encounters the Coast Range, it rises steeply, cools, and loses moisture through condensation, which produces heavy rain. The Pacific Ocean, the moisture-laden air above it, and the storms moving from it over the Oregon coast, are major factors in the state's precipitation patterns. Precipitation in the state varies widely: some western coastal slopes approach 200 inches (5,100 mm) annually, while the driest places, such as the Alvord Desert (in the rain shadow of Steens Mountain) in eastern Oregon, get as little as 5 inches (130 mm). Precipitation Oregon rainfall varies widely from region to region. The high desert region of the state is much drier, with less rain, more snow, colder winters, and hotter summers. Temperatures can get very cold, but only occasionally, as the result of Arctic cold waves. West of the Cascade Range, winters are chilly with frequent rain and occasional snow. Eastern Oregon falls into the cold semi-arid climate (or BSk type), which features drier weather. Trewartha climate types of OregonĪccording to the Köppen climate classification, most of Western Oregon has a warm-summer Mediterranean climate (or Csb type), which features warm, dry summers, and wet winters with frequent overcast and cloudy skies. Current climate details for Oregon Köppen climate types of Oregon, using 1991-2020 climate normals.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |