After record-breaking rain, clear skies in the Seattle area will offer rare chance to see aurora borealis

Following record-breaking rain on Thursday, clear skies and the possibility of a strong G3-class geomagnetic storm on Saturday could provide Western Washington residents a rare opportunity to see the northern lights.

Geomagnetic storms occur when a flare-up on the sun — in this case one that occurred Thursday — shoots out a coronal mass ejection, or a persistent high-speed solar wind stream, that streams past Earth, according to the Astronomy North Northern Lighthouse Project.

This causes the Earth’s magnetic field to become unsettled, and if that lasts long enough, can become a geomagnetic storm that could cause voltage irregularities and false alarms from security devices as well as hours of vibrant auroras.

On Saturday and even into Sunday, the auroras could be visible as far south as Oregon, according to the National Oceanic and Atmospheric Administration.

Because the solar radiation is expected to be in flux for a relatively long period — more than 24 hours — Maddie Kristell of the National Weather Service in Seattle said there could be several opportunities to see the lights.

The best will likely be early Saturday morning between 4 a.m. and 6 a.m., as well as between sunset Saturday and 3 a.m. Sunday.

On Thursday, Seattle broke a daily record for rainfall with 1.99 inches of rain recorded at Sea-Tac International Airport. The city’s yearly rainfall total rose to above normal for the first time in more than four months, according to the National Weather Service in Seattle.

It was the “wettest October day since the all time wettest day in Seattle history, when just over 5 inches fell on October 20, 2003,” the weather service said on Twitter.

But that rain is behind us, at least for the weekend, according the weather service, and the weekend looks clear and dry.

Though city lights could interfere with aurora, it’s worth a shot: Get to a dark spot, let your eyes adjust and look to the north close to the horizon.