If you have never seen the aurora borealis you are really missing something special.
The Aurora Borealis (Northern Lights as they are more commonly known) can be spectacular. Their colors vary including red, green, and purple and they sometimes appear to dance across the sky.
The Northern Lights are commonly seen in the extreme northern and southern latitudes as you get closer to the true magnetic north and south poles of the earth. Some claim to actually be able to hear them.
I have seen some spectacular northern lights in the Tri-Cities several times over the last 20 years I have been watching for them. They are not common but when you get to see them they are really cool.
We need some serious solar activity to be able to see the Northern Lights in the Tri-Cities. Monitoring solar activity through the websites of spaceweather.com or the POES Auroral Activty at NOAA is a good starting point.
We need a KP index of 5-7 (found on the first webpage of spaceweather.com) or a POES auroral activity level of 9-10 (found on the POES NOAA webpage) to have a chance to see the Northern Lights. If you find indexes this high, simply look to the north from time to time.
For some really cool video of the Northern Lights, check out the work of Ole Christian Salomonsen, it is truly amazing and beautiful. The Land Of Northern Lights
You may wish to check out the monthly aurora galleries at spaceweather.com (click her for the April 2011 Gallery) for some current photos of the Northern Lights along with their location.
I am considering starting a Twitter alert for when Northern Lights are viewable in the Tri-Cities. Drop me a comment if you are interested and good luck to you in being able to see the Northern Lights.