Strange Clouds Over Mount Hood & Mount Jefferson Are Signs Of Changing Weather

When I was on vacation last year in Central Oregon, I had a farmer tell me that he never cuts hay if clouds are appearing above Mount Hood. He was talking about the same type of strange looking clouds that appeared over our mountains on Thursday evening February 3rd, 2011.

In meteorology we call them Lenticular clouds. But they have a ton of nicknames. UFO clouds. Pancake clouds. Cap clouds. In this awesome shot from the Columbia River Gorge looking back at Mount Hood, it looks like the mountain is wearing a cap, doesn’t it? Finally, a nickname that actually makes sense!

Strange Looking Lenticular Clouds A Sign Of Changing Weather

So what do these Lenticular clouds mean and how do they form? Here are some basics:

• if you see mountains that are cloud free and in the clear, that tells you the atmosphere is quite dry.
• when you see clouds starting to form on top of or just downwind from mountain peaks, that means moisture is increasing in the air. a dry stretch may be ending.
• it may be sunny everywhere else but when moving air hits a mountain peak that air can lift and cool just enough to form a Lenticular cloud.

Lenticular Cloud Forming On Mount Jefferson Feb 3, 2011, Dave Cleary photo

The strange looking clouds that formed on Thursday definitely were a sign that our dry stretch is coming to an end. If you’ve missed the forecast lately then the changing weather might catch you by surprise.

But that Central Oregon farmer? He already knows rain is in the forecast  because he’s been watching the clouds form on top of our Pacific Northwest mountains!