Seattle’s final fling with hot weather featured a celestial fireworks show on Wednesday night, in the form of an auroral display that benefited from clear skies as well as a strong geomagnetic storm.
The northern lights were pumped up by a wave of electrically charged particles thrown off by the sun a couple of days earlier — a phenomenon technically known as a coronal hole high-speed stream.
SpaceWeather.com reported that heightened auroras were spotted along the northern tier of the U.S., including Washington as well as Montana, Minnesota, Wisconsin, Illinois and Michigan.
Seattle’s auroral glow might have seemed faint to the naked eye, but long-exposure photography brought out shimmering colors, as seen in these pictures and videos:
https://twitter.com/NWSSeattle/status/913349001428090880
https://twitter.com/Skunkbayweather/status/913426655523115008
https://twitter.com/timdurkan/status/913426425255833600
https://twitter.com/Skunkbayweather/status/913418384510877696
https://twitter.com/Greyrock360/status/913291356897918976
https://twitter.com/ClineNorthwest/status/913289465103228929
https://twitter.com/WildNWBeauty/status/913381887120310274
https://twitter.com/arebee/status/913320864493404160
https://twitter.com/NWSSeattle/status/913374998932238336
We’re not likely to see another show like this for a while. For one thing, the forecast for space weather isn’t as stormy. The National Weather Service’s Space Weather Prediction Center says the outlook calls for reduced geomagnetic activity, although regions farther north might still see auroras.
The other factor is that the Seattle area will be reverting to a more typical weather pattern overnight. University of Washington atmospheric scientist Cliff Mass explains that a temporary ridge of high pressure is giving way to a low-pressure trough, signaling an end to “the last warm days of the year.”
The National Weather Service’s Seattle office went so far as to call Wednesday night “our final clear night for the foreseeable future.” Now there’s a sobering thought for skywatchers …