According to Matthew Cullen, a meteorologist at the National Weather Service in Portland, it takes two forces aligning for viewing of the Northern Lights to be possible: space weather and Earth weather.
Right now, the Earth weather is definitely cooperating. So it's down to the space weather.
"There is a geomagnetic storm watch," Cullen said over the phone Tuesday. It is geomagnetic storms that creates the conditions needed for Aurora Borealis.
Right now, the Space Weather Prediction Center gives the Portland area about a 10 percent chance of seeing the Northern Lights early Wednesday morning. But, if you can head north, chances increase.
"The best chances will the most likely will be as far south as south western Washington," Cullen said.
"Chances will be higher as you go north," he added, "especially north of Seattle."
Even if the lights are visible, Cullen added, you'll need to get away from the city to see them.
While it is somewhat rare to see geomagnetic storms bring the chances of an Aurora Borealis sighting this far south, Cullen said it isn't unheard of.
"Storms of the this magnitude happen a handful of times every year," he said. But because of the Earth weather in the Pacific Northwest, he said, the odds aren't usually great that anyone will see the lights.
While Cullen conceded the chance anyone in Oregon will see the Aurora is "pretty small," he said there is some good news: on Wednesday morning, just before sunrise when the lights would be visible, the skies will be clear.
-- Lizzy Acker
503-221-8052
lacker@oregonian.com, @lizzzyacker