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© Austin EnvironmentalWindthrow, where strong winds snap trees off close to the ground, was evident around Astoria in December 2007.
For the first time since the Great Coastal Gale of '07 - and only the second time in its history - the National Weather Service in Portland has issued a hurricane force wind warning for the Oregon Coast.

The warning extends from Cascade Head north of Lincoln City, south to Florence and out to sea 60 nautical miles and is in effect from 4 a.m. to 1 p.m. Wednesday.

The Great Coastal Gale of '07 raked the Oregon Coast on Dec. 1-3, 2007, and brought with it the strongest wind gusts since the Columbus Day Storm of October 1962.

The storm snapped off hundreds of trees, and included wind gusts well in excess of 100 mph, with the strongest recorded gust of 129 mph at Bay City. The storm, really two systems that stretched over three days, included heavy rains and extensive flooding.

Steve Todd, meteorologist-in-charge of the National Weather Service in Portland said the storm's center is expected to make landfall over the mouth of the Columbia River, setting up a tight pressure gradient that could generate up to 100 mph winds.

"These are the kind of storms that typically knock trees down,'' Todd said. "Anytime you get winds up into the 90+mph range, it can cause property damage and bring down power lines. People need to be careful tonight."

Todd said the storm is packing a low level wind phenomenon known as a "coastal jet."

"It's a terrain influenced jet stream at low levels not associated with the upper jet stream," Todd said. "But it's a core of strong winds not too far off the surface. That core drops down to the surface and creates winds of 75 mph and above. We could see gusts up to 90 mph, maybe even a stray 100 mph gust."

Although snow remains in the forecast for the Portland area overnight, Todd said there is not a really cold pool of air in eastern Oregon to enhance snowfall in the region.

That said, the forecast for Portland still calls for heavy snow overnight until about 10 a.m. Wednesday morning before it changes to rain. One to 3 inches could fall, but it will be brief and melt quickly under the onslaught of rain and warmer temperatures.

"The boundary between rain and snow is going to be right around Portland,'' Todd said. "The best chance for snow is going to be on the east side of the city, and from Portland north."

Winds associated with this storm are expected to push gusts to around 40 mph in the Portland metropolitan area, with heavy rain nearly every day into the weekend. Rapid rises in area rivers are also a concern, forecasters said, especially Thursday and Friday. But the weather fun won't stop then: Rain, wind and lots of it remains in the forecast all the way into next weekend.