When is the next time that the Northern Lights will be clearly visible from the Pacific Northwest area (near Portland)?
There’s another good site for forecasting these things: http://www.sec.noaa.gov/today.html And here’s some more general info which also mentions these sites: The beautiful blaze of the Northern Lights, or Aurora Borealis, is caused when material thrown off the surface of the sun collides with the atmosphere of the Earth. Thus, by following events on the sun and the velocities of the gaseous matter being thrown off its surface, we can predict the appearance of the Northern Lights with a fair degree of accuracy — certainly enough to meet the needs of the average observer of the night sky. These predictions and observations are collectively referred to in the style of weather forecasting as ‘space weather’. The aurorae appear over the Earth’s polar regions in what are known as the auroral ovals; in the northern hemisphere the auroral oval bulges that much further to the south, the stronger the solar wind is at any given momen
