“Major Windstorms” by Tyree Wilde, NOAA-National Weather Service
We were treated to
two presentations, both related to extreme weather events. So, 22 guests showed up at the KPTV/FOX-12
Tyree explained the components of a windstorm: offshore development and the presence of an upper level low. Most PNW windstorms occur October through March. The jet stream and forecast of the storm track is critical to determining the impacted areas. The strongest winds are ~300 miles wide. The lifecycle is ~48 hours. Rapid storm development and complexity are factors that are hard to predict. A major windstorm is a once in ten-year event. Common damage includes fallen trees, down power lines, closed roads, and damaged houses.
It is worth noting
the major windstorms of the last 50 years.
The Columbus Day Storm, the Granddaddy of all
“Rain Events of November 2006” by Drew Jackson, KPTV/FOX-12
presentation documented the multiple impacts of the intense rain events of
early November 2006. The “Pineapple
Express” pattern (i.e., jet stream pushing much moisture from the tropics)
dominated our weather in early November.
The rainfall totals during the peak of one storm, November 6th and 7th,
were record-breaking at many sites: 14.3 inches at Lee’s Camp (
The rain totals are
comparable to the February 1996 flood event (but without the low-elevation
The big news story
State Highway 35,
just east of
There are three theories as to the cause: (1) Glacial retreat (due to climate change) which exposes more sediment that can be flushed out in an intense rain. (2) Return to a “wet cycle” (long-term trend) where more rain is occurring. (3) Coincidence with a series of several hot dry summers (enhancing glacial retreat) and a “Pineapple Express” weather pattern, which happened a lot during the 1990s to the present. Drew is leaning toward cause #3. Finally, Drew left us with food for thought: some areas experienced flooding worse than the 1996 major flood event.
After the talk concluded, and several questions were answered, Drew and Mark Nelsen took the guests on a tour of the studio—a first time for some folks. New state-of-the art computers and graphics were demonstrated. We appreciated the hospitality of our hosts.
Note-taker: Kyle Dittmer, OR-AMS President