Rivers are not expected to flood, but heavy rains in the coastal range often cause mudslides and localized flooding of streams. We recommend the following:
Statement as of 2:29 PM PDT on October 15, 2009
... Heavy rain expected Friday night and Saturday...
An unusually wet early season system is expected to dump
several inches of rain over the area early this weekend. The bulk
of the rain will fall from late Friday afternoon through Saturday
as the system taps into a tropical air mass. Models are in
agreement on bringing the front onshore and then stalling it...
although details on where the heaviest rain will fall are still
evolving. As the front stalls the system will usher in a warm and
moist air mass and consequently wring it out over northwest
Oregon and southwest Washington. Rainfall accumulations are
expected to be 2 to 5 inches in the Coast Range... 1 to 2 inches
northern portions of Willamette Valley... 2 to 4 inches in the
South Washington and north Oregon Cascades... and around an inch
Since this system is coming early in the year when rivers are near
their Summer lows... river flooding should not be much of a
concern. However... local areas may see higher than expected
accumulations and therefore local flooding of small streams
remains a possibility. Remember to maintain a higher awareness
level and keep informed on this developing scenario.
Monitor NOAA Weather Radio or weather.Gov/Portland for the latest
information... forecasts... and warnings.