An eruption on the surface of the Sun in an area called Region 1429 has been streaming charged particles over the past day or so.  

At about 8 a.m. Pacific time, there was a massive coronal mass ejection (CME) from the region.  The CME is hurtling toward earth at hundreds of miles per second, and is expected to impact the earth's magnetosphere tonight at between Midnight and 1 a.m. Pacific time.

Here's an animation of the actual eruption:

http://www.youtube.com/watch?v=uecMk8ZZ1uE

...and a NASA video:

http://bcove.me/wri3adeq

WATCH: Forecast animation of CME impact (time in UTC, subtract eight hours for Pacific Standard Time)

This CME is forecast to cause a geomagnetic storm on the order of three on a scale of one to five.   This could cause temporary degrading of GPS signals, widespread disruption of high-frequency radio communications (not your AM or FM radio), and could require a re-routing of airline flights over polar regions where a loss of radio communication would pose a danger in an emergency.   Orbiting satellites could be briefly affected, and there is only a slim chance of damage to power grids on the surface.

Humans on earth are not threatened by these particles, but will be treated to quite a light show as the shock wave passes the planet.  This CME is expected to hit the Earth's outer protective magnetosphere at a speed of 500 miles per second!

The Space Weather Prediction Center now expects the Aurora Borealis, or Northern Lights to be visible at latitudes as far south as Oregon!   The best time to go look outside in the northern sky will be around the Midnight hour through sunrise Thursday.

Skies over Western Washington should be mainly clear.  

However, the one problem factor is the moon.  The moon will be full tonight and moving across the Northwest sky right during prime time!   The moon rises this afternoon at 5:49 p.m. and will be directly overhead and shining brightly just after midnight as the auroral show is expected to get underway.

The best viewing possibilities will be away from city lights, and the farther north, the better.

Here's an animation from NASA which illustrates the protective effects of the planet's magnetic field!

http://bcove.me/emziut2s

If you get great pictures of the Northern Lights, send them to us at newstips@kirotv.com!  

Join me for the KIRO 7 Weather Chat Thursday night at 7.30 p.m. Pacific at KIROTV.com.