SEATTLE— The first wind storms of the fall season don’t have to be the first strongest of the year to cause the most damage.

At this time of year, when the trees are still fairly fully leafed (and some branches have been naturally weakened by the dry and hot summer months), it doesn’t take much wind to bring down a branch or two.

That’s why early fall storms are called “Mother Nature’s tree trimmers.”

A tight, compact low will quickly swing past Western Washington overnight. So we are going from nice and dry and a bit windy today to wind gusts of 70 km per hour in some places during the night. Rains will also develop.

A wind advisory is in effect Friday through early Saturday morning for the North Coast, Admiralty Inlet Area and San Juan County. These are the areas most at risk of power outages and damage to tree branches at night, especially on the south-facing parts of those islands.

Gale warnings for dangerous seas are in effect this evening for the eastern entrance waters of the Strait of Juan De Fuca, Admiralty Inlet and Pacific Coastal waters.

Some forecast models are even predicting wind gusts of 50 to 60 miles per hour near Friday Harbor and Oak Harbor. Damage to trees and downed power lines are likely there after dark Friday and early Saturday morning.

From Mukilteo south towards Olympia, lighter winds of 30 to 55 km/h are more possible, but a stray gust of 65 to 70 km/h is possible.

Gale warnings for dangerous seas are in effect this evening for the eastern entrance waters of the Strait of Juan De Fuca and Admiralty Inlet and Pacific coastal waters.

Winds are expected to start picking up around The Sound on Friday evening and will be strongest until 7am on Saturday morning. On some islands, wind gusts can reach almost 100 km per hour, as the wind passes through showers that pass through.

Winds will decrease during the day on Saturday with isolated showers continuing through Sunday and easing on Monday. Lowland locations will see 1 inch of precipitation possible throughout the weekend, with 3 inches possible in the mountains.