Oregon climates
Jane McGary (Wed, 19 Jul 2006 18:45:04 PDT)
Dell asked,
At 02:31 PM 7/19/2006 -0400, you wrote:
Dear Jane and Joyce and others who live in Oregon,
I recently visited relatives in Tigard, OR (SW of Portland) and traveled to
the vicinity of Mt Hood, the fruit growing region on the northeast of the
mountain. I know that in CA, the climate/zone/temps and rainfall can vary
dramatically from east to west. My relatives told me that in Tigard, there
is very little snow and temps rarely get lower than 25F. Is this also true
of Gresham, Estacada, and other towns east of Portland?
No, it is not. Towns east of Portland, especially Gresham, Sandy, and
Troutdale, are subject to continental east winds through the Columbia
Gorge, which can drop the temperature drastically in winter and raise it in
summer. The Estacada area, where I live, experiences somewhat less severe
east winds through the Clackamas River gap in the Cascades. Tigard is
nearly at sea level (I think about 40 feet elevation) in the flat
Willamette Valley, whereas my land is at 1600 feet in the Cascade
foothills (southwwest of Mt. Hood) and is usually 5 to 10 degrees F colder
than the Portland airport, which is in turn somewhat colder than it would
be in Tigard, West Linn, Lake Oswego, and some of the other suburbs
southwest of the Portland city center. However, these western suburbs can
experience colder temperatures when an inversion layer associated with the
Coast Range lies above them. Snowfall in the Portland area occurs quite
variably and is much more common above 1000 feet elevation -- such as on
the high ridges west of the city center, or in areas to the east such as
where I live. Such microclimatic variation is typical of parts of the
western USA near high mountains and major rivers.
Jane McGary
Northwestern Oregon, USA