Windy Days

We’ve had some windy days lately. Two days ago (October 20, 2019) we had gusts up to 40 mph (miles per hour) — it was hard to walk in that wind!

As we battled the blustery weather while walking the dogs, I happened to look to the west, where I saw lens-shaped clouds hovering over the tops of the mountains.

Once inside, I decided to clean up some photos on the computer. I happened across this shot of Longs Peak from near Estes Park from fifteen years ago.

North Face of Longs Peak

North Face of Longs Peak, October 2006

What caught my eye initially was the odd shaped cloud over the east face of the mountain top — just like what I’d seen while walking the dogs. This is called a ‘lenticular cloud’, meaning lens-shaped. Lenticular clouds indicate that the wind is really ripping, pulling relatively moister air up to the top of the mountain, where it forms a cloud as it crosses over. Although these clouds seem to stand still, in reality, they are constantly forming on the near side, then evaporating on the far.

Estes Longs 6..JPG

Notice the snow blowing off the ridge to the right (west) and dropping into the basin below the summit. This extra snow helps build glaciers.

According to the Rocky Mountain National Park Service Wind page, in the winter, the average daily wind speeds on Longs Peak are 65 mph, so the average is higher than our peak wind speed on Sunday. It often blows at over 100 mph, and the maximum wind speed recorded was in excess of 200 mph!

Suddenly, I’m more appreciative of our relatively calm air.

NASA Computer Simulation Shows 2017 Hurricane Tracks

This computer simulation from NASA shows just how interconnected the world is.
https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=12772&button=recent

The computer simulation runs from August 1 through November 1, 2017. It follows hurricanes that tracked over the Atlantic Ocean this fall, letting you see how dust from the Sahara ends up in Miami, and smoke from the wildfires in California and British Columbia migrates all the way to Europe.

The first time through, listen to the narration. It explains a lot of what you are seeing, points out the storms and how unusual they were.

The second time through, watch what’s happening in just one region. You can see storm fronts come through, then dissipate as other systems disrupt them. It looks like the planet is breathing.

Night-glowing Clouds

I saw these clouds outside my back door last night, just as the sun was setting.

Evening Glories 2.jpg

 

I think they are noctilucent clouds — nocti means nigh and lucent means glowing or shining.

Noctilucent clouds form when there is a lot of ice particles from water vapor extremely high in the atmosphere.Mysterious Glowing Clouds Appear Across America’s Night Skys In fact, noctilucent clouds are the highest kind of clouds that form.

 

Photo courtesy NASA http://spaceflight.nasa.gov/gallery/images/station/crew-17/html/iss017e011632.html. The noctiluscent clouds glow right at the edge of the atmosphere.

 

If you are thinking that you’ve never seen clouds like this before, you are not alone — noctiluscent clouds have only been reported since 1883. They are, however, becoming more common and brighter. They are also showing up in the mid-latitudes — as far south as Colorado. Nobody knows why.NASA: Strange Clouds

What makes this shot so interesting is that the sun is so low on the horizon and the ice crystals that form the clouds so high that other clouds block the sun’s rays, giving the noctilucent clouds a streaked appearance.

Colorado Monsoons

The weatherman is calling for thunderstorms tonight, as “monsoon moisture returns to the state.”
I always feel weather forecasters are a little presumptuous calling summer moisture in Colorado monsoons.  I mean, although we can have the occasionalImage gully-washer, our piddly precip is nothing compared with the six months of torrential rain that most people normally think of when they hear the word monsoon.
But according to weather people, “a monsoon is a wind that changes direction with the seasons”. By that definition, the Southwest, with Colorado on it’s northern edge, has a monsoon.  Summer heat on the desert of Southwest Arizona, California, old and New Mexico warms the air there, causing it to rise.  This creates a vacuum, called a low Imagepressure cell.  The low pressure sucks moist air from the Pacific and Gulfs of California and Mexico, bringing storms to the west and southwest part of the state and

You can see the center of the low pressure system as a lack of clouds in Chihuahua Mexico. This system spun up into the Front Range of Colorado, where it dropped over half an inch of rain.

You can see the center of the low pressure system as a lack of clouds in Chihuahua Mexico. This system spun up into the Front Range of Colorado, where it dropped over half an inch of rain.

occasionally onto the plains. In winter, the Southwest deserts cool, and create a high pressure cell that can keep moisture out.
These summer storms don’t compare to the classic monsoons of Asia and east Africa, but Coloradoans are usually glad to get moisture in any form.