Great Fall Superstorm of 2021 Oregon and Washington Impacts

Oragon and Washington Impacts
The low pressure when it made landfall
Type:	Moderate low pressure
Hazards Produced:	Damaging Winds, Severe Storms, Flooding, Tornadoes, Storm Surge

The Great Fall Superstorm of 2021 Oregon and Washington Impacts

The low pressure system made landfall near the Oregon and Washington Boarder with a pressure around 980 Mb. The low pressure would began to strengthen more quickly and left Washington and Oregon with a pressure of 974 Mb. Multiple dangerous hazards were created due to this system. High winds caused damage in both states. The low brought in large amounts of moisture from the Pacific Ocean dropping massive amounts of rainfall in both states. Although the environment was not particularly conductive for severe thunderstorms, but the rotation of the low allowed several tornadoes to form. Minor storm surge on the coast also resulted. Severe erosion to the coastline and inland flooding occurred as the highest recorded storm surge was around 8 feet.

High Winds

The low pressure system caused both states to experience at least a day of high winds. Most locations had sustained winds of at least 30-35 MPH with gusts between 50 to 60 MPH. These winds caused driving difficulties and downed many trees. Many power outages also occurred. Southern Washington and northern Oregon got the worst winds though. Sustained winds of 40-55 MPH where common and gusts 65-75 MPH occurred. The highest gusts recorded was 83 MPH. Significant tree damage and power outages occurred.

Gallery of Wind:

An old tree downed by high winds

Flooding and Severe Storms

The low pulled tons of moisture of the Pacific resulting in disastrous rainfall across the states. Widespread amounts of 25-36 inches occurred and the highest rainfall occurred around the Portland, and Salem Area with a general 40-63 inches of rain. Imbedded severe storms also occurred but since the environment was not that conductive for severe thunderstorms besides the increased sheer around the center of the low, these storms were generally low end severe. Storm Surge of 3-7 ft occurred as well causing severe inland flooding and destructive waves.

Below is a total rainfall reports table for a few locations:

Loaction	Amount (in)
Portland OR	57
Salem OR	63
Seattle WA	26
Chiloquin OR	15
Eugene OR	38
Olympia WA	24

Gallery of Flooding and Storm Surge:

Flooding around the Portland area

Storm Surge Damage to a house in Oregon

Extreme Flooding in Salem OR

Damaging thunderstorm winds and hail reports:

Location	Type	Strength/Size	Notes
Seattle WA	Hail	2.75 inch	Significant damage to roofs and siding. Shattered windows and severe damage to cars. 2 injured from falling hail.
Seattle WA	Hail	2.5 inch	Tennis ball sized hail caused severe damage.
Seattle WA	Wind	80 MPH	Occurred with tennis and baseball sized hail. Widespread tree damage and powerlines down. Roof damage also seen.
Portland OR	Wind	65 MPH	Downburst from a thunderstorm before the low made landfall. Tree and powerline damage reported.
Elma WA	Hail	1 inch	Quarter sized hail caused minor damage to windows and cars.
Lakewood WA	Wind	60 MPH	62 MPH gust recorded from a passing thunderstorm. Tree damage reported.
Lakewood WA	Hail	1.25 inch	Half Dollar sized hail caused iwndow and siding damage.
Medford OR	Wind	70 MPH	71 MPH gusts caused moderate tree damage and scattered power outages.
Grants Pass OR	Hail	1 inch	Quarter sized hail with no visable damage.

Gallery of Storms:

A thunderstorm off the Oregon Coast

A tornadic thunderstorm near Medford Oregon with a wall cloud.