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WWUS86 KPDT 112138
SPSPDT

Special Weather Statement
National Weather Service Pendleton OR
238 PM PDT Sat May 11 2024

ORZ041-044-049-050-502-503-505>511-WAZ024-026>030-521>523-121200-
Eastern Columbia River Gorge of Oregon-
Lower Columbia Basin of Oregon-Grande Ronde Valley-Wallowa County-
Northern Blue Mountains of Oregon-
Southern Blue Mountains of Oregon-John Day Basin-Ochoco-
John Day Highlands-
Foothills of the Northern Blue Mountains of Oregon-
Foothills of the Southern Blue Mountains of Oregon-
East Slopes of the Oregon Cascades-North Central Oregon-
Central Oregon-Eastern Columbia River Gorge of Washington-
Kittitas Valley-Yakima Valley-Lower Columbia Basin of Washington-
Foothills of the Blue Mountains of Washington-
Northwest Blue Mountains-Simcoe Highlands-
Upper Slopes of the Eastern Washington Cascades Crest-
Lower Slopes of the Eastern Washington Cascades Crest-
Including the cities of Arlington, The Dalles, Boardman,
Hermiston, Ione, Cove, Elgin, La Grande, Union, Enterprise,
Joseph, Wallowa, Meacham, Tollgate, Long Creek, North Powder,
Ukiah, Dayville, John Day, Mitchell, Monument, Spray, Brothers,
Paulina, Prairie City, Seneca, Athena, Pendleton, Pilot Rock,
Heppner, Condon, Fossil, Camp Sherman, La Pine, Sisters,
Sunriver, Dufur, Maupin, Moro, Bend, Madras, Prineville, Redmond,
White Salmon, Ellensburg, Thorp, Naches, Sunnyside, Toppenish,
Yakima, Connell, Prosser, Tri-Cities, Dayton, Waitsburg,
Walla Walla, Ski Bluewood Resort, Goldendale, Bickleton, Roslyn,
Easton, Appleton, Cle Elum, and Cliffdell
238 PM PDT Sat May 11 2024

...EXTREME GEOMAGNETIC CONDITIONS OBSERVED AND CONTINUED SEVERE
GEOMAGNETIC STORM EXPECTED TO CONTINUE THROUGH THE WEEKEND...

The NOAA Space Weather Prediction Center has observed extreme (G5)
geomagnetic conditions Saturday morning and expect severe (G4)
conditions to continue through the weekend.

* A Geomagnetic Storm of this strength can cause multiple and
  widespread issues with various power and communication systems.

* Widespread voltage control problems may occur; some power grid
  systems may experience component failures, disruption of service
  and protective device trips. This could result in blackouts.

* Pipeline currents can reach hundreds of amps.

* GPS and other satellite navigation may be degraded or
  unavailable for days.

* High Frequency (HF) radio propagation may be impossible in many
  areas for one or two days.

* Low-frequency radio navigation can be out for hours.

* Aurora may be visible at much lower latitudes.

For Space Weather Information visit...www.swpc.noaa.gov
For Weather Information visit...www.weather.gov

$$