Amazing Lenticular Clouds and Weekend Weather

A weak front is now moving into the the region from the north. You can see the thickening clouds aloft...and they are evident in a recent high resolution visible satellite picture (see attached). The latest radar show some showers over the northern part of the state...they are all light (see radar image). Tomorrow a stronger system will be over us, and should produce a well-defined convergence zone (with moderate rain) over central Puget Sound. There will be showers in the mountains with snow down to 3000-4000 ft. Monday still looks dry...except for a few lingering showers in the mountains.

Yesterday, there were the most amazing wave clouds near Mt. Rainier (a sample picture is attached by Tim Thompson). KOMO TV has placed a number of the pictures online at
http://www.komonews.com/weather/blog/35631614.html

These are mountain wave clouds produced by air being forced to rise and sink by the mountain. The mountains displace the air upwards and then it goes up and down for a while. Where the air goes up..you get clouds, down clear air. These clouds often are lens shaped...and have been mistaken for flying saucers. In fact, the flying saucer craze started in 1947...and where was the first UFO seen?...Mt Rainier! I bet you can guess what it really was. I have a large section in my book on these mountain wave clouds.

Weekend Weather

Another dry day. This morning this were some very nice lenticular or mountain wave clouds over and downstream of Mt. Rainier. I grabbed a poor image of them from the Puget Sound Clean Air Agency visibility web cam (see to the right). This cam is there to help document variations in horizontal visibility of the region--you can see it at: http://www.pscleanair.org/airq/visibility/default.aspx. We have an inversion over us right now...with temps at 2000-2500 ft about 10F warmer at the surface. There was a wide range of temperatures at sunrise...from the mid40s near the water to just below freezing in the hinterlands.
Tomorrow will start off dry, but a weak front will approach during the afternoon. So increasingly clouds and some showers late in the day and tomorrow evening. Seattle will not get much due to rainshadowing off the Olympics. Sunday a weak trough will move through with some more showers in mountains and an active Puget Sound convergence zone north of Seattle.
Monday looks dry as another ridge moves in. Looking further afield...a warm front should move in on Tuesday with some rain...but temps will incease sufficiently to leave snow only at the highest elevations in the Cascades.
I can't believe it...but another major ridge of high pressure latter in the week. I would be nervous if I was running a low-elevation ski area now....