Fog and Atmospheric Optics

Fog with a Glory, Brocken spectre, and two segments of a fogbow.

In the wake of a departing low pressure system I expected that there might be areas of dense fog in the morning. I awoke well before sunrise to look at satellite images to see if fog was developing. And, yes, there were some hints that fog was present. Good!

GOES-16 IR satellite image from ~5 a.m. showing large areas of fog across northern Arizona.
GOES-16 IR satellite image from ~5 a.m. showing large areas of fog across northern Arizona.

I left the house around 6 a.m. and headed east on Lake Mary Road. A few miles outside of town I ran into fog. Visibility dropped quickly to around 1/4 mile. Drive carefully!

My destination was the Mormon Lake Overlook. I had some success last winter at this site with a similar fog situation. As I approached the overlook the fog lifted becoming a low cloud deck above me. Hmmmm….not quite what I wanted. Ahead, I could see the edge of the cloud/fog. As I made the final approach to the overlook the road gained a bit of elevation and, suddenly, I was above the cloud/fog deck. Wonderful.

The sun had not yet risen but it was light enough to see that there was a shallow layer of fog covering the Mormon Lake basin. Moments later the sun began to rise through the dense fog.

Sunrise through the fog.
Sunrise through the fog.
Layers of fog at sunrise.
Layers of fog at sunrise.

With the sunrise a Glory and Brocken spectre became visible. Moments later, two short segments of a fog bow appeared. Also visible is a shadow of the overlook.

Fog with a Glory, Brocken spectre, and two segments of a fogbow.
Fog with a Glory, Brocken spectre, and two segments of a fogbow.
Fog begins to dissipate across the Mormon Lake basin.
Fog begins to dissipate across the Mormon Lake basin.

As the fog began to dissipate over Mormon Lake, I headed towards Anderson Mesa Station (home to several telescopes) because it is high enough to be above the fog. But first, along the way, the road dropped down into the fog and I saw this fog bow.

Fogbow near Lake Mary.
Fogbow near Lake Mary.

Finally, atop Anderson Mesa I once again was above the fog and able to photograph a Glory—this time projected onto trees with autumn colors.

Another glory and Brocken spectre projected onto fall foliage.
Another glory and Brocken spectre projected onto fall foliage.

Finally, here is a time-lapse of the fog over Mormon Lake that includes the Glory and the right-hand side of the fog bow.

Edit: Replaced GOES-16 visibile image with IR image.

Mormon Lake with Fog, Snow, Rime, and a Glory

A winter storm in late February brought hope again of getting some photographs of the San Francisco Peaks covered in snow. So I departed before sunrise one morning to head out towards Mormon Lake. Because of the warm winter up through mid-February, most of Lower Lake Mary and Upper Lake Mary remained mostly ice free. With very cold early morning temperatures it was no surprise that there was fog over the relatively warm open waters of the lakes. When I left my house, the temperature was about +3°F. When I reached Lower Lake Mary, the temperature had fallen to -10°F—and there was considerable fog.

A shallow layer of fog covers Mormon Lake.
A shallow layer of fog covers Mormon Lake.

It was the same over Upper Lake Mary. I debated whether to change my plans and shoot photographs of the fog over this lake but after viewing the scene I chose to continue to the Mormon Lake Overlook. As I approached the overlook, I could see a layer of fog. Luckily, the overlook was just high enough to be above the fog.

It was a beautiful scene with a shallow layer of fog covering the lake bed and snow on the distant San Francisco Peaks.

San Francisco Peaks as seen from the Mormon Lake Overlook.
San Francisco Peaks as seen from the Mormon Lake Overlook.

After getting a few quick photos I set about to capture a panorama. I shot 12 images: 2 rows of 6 shots. The resulting image is huge and clocks in around 190 megapixels. I can make a print of this that’s 8 feet wide. But I probably won’t because I don’t have a wall large enough for something that big.

It was obvious that sometime during the night the fog layer was much deeper as all the grasses, bushes, and trees were covered with rime ice.

Rime ice coats the grasses and bushes.
Rime ice coats the grasses and bushes.
Rime ice coats the grasses and bushes.
Rime ice coats the grasses and bushes.

The rime created needles that pointed in the direction of the light wind that had been present during formation. As the sun rose above the horizon, the rime caught the light and sparkled brilliantly.

A glory and a small segment of a fog bow are visible on the fog layer.
A glory and a small segment of a fog bow are visible on the fog layer.

So we had fog over the lake bed, snow on the mountain, and rime ice on the grasses. What else? Well, a glory became visible as the sun rose high enough to illuminate the fog layer below me. And a short segment of a fog bow was also visible in the fog layer.

Not a bad day for photography.