High Altitude Winds

Although noted for its harsh winters, Interior Alaska enjoys a climate notably free of severe wind. However gale-force winds are present on most evenings high overhead, at altitudes above 100 miles. Winds exceeding 100 mph occur sometime during nearly everyday; sometimes they are in excess of 200 mph. The high-altitude wind is usually westward in late afternoon and eastward in early morning.

While not entirely understood, these winds near the fringe of space are known to be caused by the interaction between the earth's magnetic field and the solar wind, a never-ending stream of matter flowing out from the sun. The interaction causes charged particles in the atmosphere to move rapidly! These collide with the air and cause it to move as well. Even though of very high speed, these winds have little effect because the air at this high altitude is only about one billionth as dense as that at the surface.