February 22, 2020

Stunning Lenticular Clouds Downstream of Mount Rainier

Native Americans, who were astute observers of the natural environment, had a saying:  "when Tahoma (Mount Rainier) has a hat, rain will soon follow."

Today it developed a hat of great beauty.

Looking out the window of my colleague, Qiang Fu, this afternoon, I saw it.  A series of stacked lenticular (lens-shaped) clouds downstream (west) of Mount Rainier (see below).  Stunning.

A bit closer view by Nicole Geer (below) shows the structure a bit better.

But why not go far closer....say from the nearby peak of Crystal Mountain, the home of a wonderful 360° high resolution live cam?

The view around 4 PM was extraordinary, with the "stacked plates" of several lenticular/mountain wave clouds clearly evident.

Pull back and you can get some perspective.  Stunning

And as the sun set and dusk settled in, the lenticular clouds remained, even as the general sky cleared a bit.  

As discussed before in this blog, lenticular clouds form as air is forced to rise by a mountain barrier, and then, like a swing, oscillates back and forth in the vertical (see figure below from my weather book).  As the air rises, it cools, and if moist enough, a lens-shaped cloud forms--with the potential to get several stacked clouds depending on the moisture structure in the vertical.  The clouds evaporate as the oscillating air sinks.

Having air close to saturation is good for the development of lenticular clouds, as is increasing wind approaching the mountain.  Both occur as weather systems approach the area--thus, there is good physical reasons for the Native American observation about a "hat" forming on the big mountain before rain falls.  In fact, the 1:30 PM infrared satellite image Friday (see below) DOES shows a weather system offshore--one that is heading towards our region.

Bottom line:  If you don't have a weather satellite handy, you can learn a great deal about future weather by being a perceptive observer.


  1. Saw some very nice lenticular caps over Mt Baker yesterday on my drive home from work, best I have seen in awhile. And sure enough woke early this morning to wind and rain in Bellingham.

  2. Yestersday, the hat over Mt Rainier looked amazing

  3. Beautiful photos, and thank you for the explanation of this local phenomenon! I did want to comment, however, on the use of the past tense when referring to Native Americans. When we use the past tense, it implies that Native Americans are no longer here, when in fact, there are thriving Native communities across the Northwest -- and across the country. Using the present tense helps to remind us of this, and shows the resilience of Native communities, who persist despite centuries of genocide and attempted historical erasure.

    1. I think his point was, they've had that saying for many years. I'm pretty sure Cliff and everyone else reading this blog are well aware Native Americans are still here.

    2. Jordan, don't be burdened by self-imposed, misplaced guilt. "Native American" is contrived, politically correct nonsense.

      The inhabitants who were here prior to the Europeans were no more "native" than we are now. Where do you think their ancestors came from? Do you think they grew up out of the ground?

  4. It's especially interesting to watch a time lapse of these events. The cloud motion near the bottom of the structure seemed to be more "agitated" than upper sections.

  5. Lenticular clouds! One of those things that makes life worth living,Cliff.

  6. Would you have any comment about the wave clouds forming over western Oregon right now (3-5PM PST on Monday 2/24)? Very "lenticular" like clouds over us here in Lebanon, Oregon! According to upper level observations, the upper level winds seem to be coming from the NNW, but there are clearly wave clouds lining up on the VIS and IR imagery this evening, and the waves appear to be retrograding (moving towards the NNW, directly against the upper level wind direction). Any thoughts??


Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

Winter-Like System in May

Tomorrow will not feel like late May, with a winter-like Pacific weather system making landfall, bringing lots of rain, wind, and cool tempe...