Windstorm

Overview:

A windstorm is generally a short duration event involving straight-line winds and/or gusts in excess of 50 mph. Windstorms affect the entire state of Oregon, and can be especially dangerous in those areas with significant tree stands, and areas with exposed property, major infrastructure, and above ground utility lines. A windstorm can knock down trees and power lines, damage homes, businesses, public facilities, and create tons of disaster related debris.

The most frequent surface winds in Oregon are from the southwest. Windstorms are often associated with storms moving onto the coast from the Pacific Ocean. West winds generated from the Pacific Ocean can be strong along the coast, but typically lose strength inland due to the obstruction of the Coastal and Cascade mountain ranges.

Though tornadoes are not common in Oregon, these events do occasionally occur and sometime produce significant property damage and even injury. Tornadoes are the most concentrated and violent storms produced by earth’s atmosphere, and can produce winds in excess of 300 mph. They have been reported in most of the counties throughout the state since 1887, but are the most prevalent in the northwest corner of the state, from Lane County up to Clatsop County. Most of them are caused by the intense local thunderstorms common between April and October.

It is not uncommon for Oregon to experience several windstorms during the winter months. The Oregon Coast has several relatively harsh storms during the winter months. Although major damage from these storms is infrequent, the Oregon Coast Region of the state is the most vulnerable to windstorms. The seven coastal counties in the Oregon Coast Region often face 60 to 100 mile an hour winds sometime during the year. While the coast is experiencing severe winds, the Willamette Valley may also face 40 to 60 mile per hour winds from the same storm.

Major windstorms that can impact large areas of the state, like the Columbus Day windstorm of 1962, are relatively rare. These storms can cause major damage to many areas of the state with the Oregon coastal counties typically suffering the most damage from this type of hazardous event. Based upon local hazard analyses the counties most vulnerable to windstorms are: Benton, Clatsop, Coos, Columbia, Curry, Douglas, Gilliam, Hood River, Lane, Lincoln, Linn, Marion, Morrow, Multnomah, Polk, Sherman, Tillamook, and Washington.

BEFORE...

Stay Informed. Weather Radios enable you to monitor weather related forecasts, watches and warnings - 24 hours a day direct from the National Weather Service.

Severe Storm Watches and Warnings

A severe storm watch indicates that severe weather may affect your area. A severe storm warning indicates that severe weather conditions are definitely on the way.

DURING...

If you are INDOORS, move away from windows or other objects that could fall, and to lower floors in multi-story buildings.

If you are OUTDOORS, move into a building and avoid downed electric power lines, utility poles, and trees.

If you are DRIVING, pull off the road and stop away from trees. If possible, walk into a safe building. Avoid overpasses, power lines and other hazards.

Listen to your radio for emergency instructions.

AFTER...

Check yourself and those around you for injuries.

Evacuate damaged buildings. Do not re-enter until declared safe by authorities.

Call 9-1-1 only to report a life threatening emergency. If you smell gas or hear a hissing sound indoors - open windows and leave the building. Turn off the gas source and call your gas company. Do not use matches, candles, open flames or electric switches indoors.

Monitor your portable or weather radio for instructions or an official "all clear" notice. Radio stations will broadcast what to do, the location of emergency shelters, medical aid stations, and the extent of damage.