The 2020 nonsoon-Monsoon

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A thin band of clouds partially blocks the sun and creates an array of crepuscular rays of light.

This is the second year in a row in which the North American Monsoon has failed to deliver its normal weather to Arizona. The monsoon had a late start in July with only a few isolated rain events early in the month and the main event starting around the third week of July. But even that faltered after a week and the final week of July was dry.

August was even worse with no measurable precipitation until after mid-month and even then the amounts were light. The National Weather Service in Flagstaff has posted some climate data for the area for August. It was the hottest August and the 2nd driest on record in Flagstaff and most of the west experienced similar conditions (Figure 1; Figure 2; Figure 3).

Photographing summer monsoon storms has been a challenge this year because there were so many dry periods. Even so, there are always interesting weather events and clouds that make it worthwhile. So here is a collection of the most interesting weather photographs from this summer.

Convection

Early stages of convection over the San Francisco Peaks as viewed from Marshall Lake.
Early stages of convection over the San Francisco Peaks as viewed from Marshall Lake.

A time-lapse movie shows that the ducks are more interesting than the convection.

Developing Cb's over the San Francisco Peaks.
Developing Cb’s over the San Francisco Peaks.
Small cumulus clouds over the Painted Desert.
Small cumulus clouds over the Painted Desert.
A weak thunderstorm near Two Guns, Arizona.
A weak thunderstorm near Two Guns, Arizona.
A well-developed thunderstorm over the Mogollon Rim viewed from Sedona.
A well-developed thunderstorm over the Mogollon Rim viewed from Sedona.

Rainbows

Full rainbows eluded me this year butI did manage to photograph a rainbow segment.

Rainbow segment over the North Rim of Grand Canyon.
Rainbow segment over the North Rim of Grand Canyon.

Lightning

As with rainbows, lightning was elusive this year. It was typically a case of being in the wrong place on the wrong day and at the wrong time. But I did get lucky with the following image.

Lightning illuminates the interior of Grand Canyon.
Lightning illuminates the interior of Grand Canyon.
In-cloud lightning illuminates a small Cb near the Grand Canyon. I was trying to photograph the comet so I got lucky with this storm.
In-cloud lightning illuminates a small Cb near the Grand Canyon. I was trying to photograph the comet so I got lucky with this storm.
Lightning at sunset over the Mogollon Rim viewed from Sedona.
Lightning at sunset over the Mogollon Rim viewed from Sedona.
Weak storms over the San Francisco Peaks produced these two bolts of lightning.
Weak storms over the San Francisco Peaks produced these two bolts of lightning.
In-cloud lightning partially illuminates Grand Canyon while the nearly-full Moon provides additional illumination.
In-cloud lightning partially illuminates Grand Canyon while the nearly-full Moon provides additional illumination.

Sunsets

And when there is no lightning and no rainbow, one can be content with the sunset.

A small rain shaft is illuminated by the setting sun.
A small rain shaft is illuminated by the setting sun.
Distant rain catches the last light of the sun and provides backlighting for the Cockscomb.
Distant rain catches the last light of the sun and provides backlighting for the Cockscomb.
A thin band of clouds partially blocks the sun and creates an array of crepuscular rays of light.
A thin band of clouds partially blocks the sun and creates an array of crepuscular rays of light.
The sun sets over ruins in Wupatki National Monument.
The sun sets over ruins in Wupatki National Monument.
The setting sun illuminates both Cathedral Rock and the clouds above.
The setting sun illuminates both Cathedral Rock and the clouds above.

Miscellaneous

Crepuscalar Rays—Wupatki National Monument.
Crepuscalar Rays—Wupatki National Monument.
Crepuscalar Rays—San Francisco Peaks.
Crepuscalar Rays—San Francisco Peaks.
Even thought it is supposed to be the wet and rainy season, we still managed to get cap clouds on the high peaks with stars above.
Even thought it is supposed to be the wet and rainy season, we still managed to get cap clouds on the high peaks with stars above.

Perhaps 2021 will be a normal monsoon year.

Perseid Meteors—2020

The Perseids meteor shower is an always popular sky event. Perhaps one reason is that it occurs during the warm summer months and can be a pleasant family event.

Perseid meteors—2020.
Perseid meteors—2020.

We found ourselves at a parking lot in Wupatki National Monument—an International Dark Sky Park. Two other groups of two were also there but the parking area is big and maintaining distance was easy.

Photographing a meteor shower is always about trade offs. If you shoot with an ultra-wide lens the meteors are small and you will likely miss some of the dimmer ones. But the wide angle view ensures that you cover a large portion of the sky.

Another option is to shoot with a lens that is in the “normal” range or even a telephoto. The disadvantage is the field of view is greatly reduced while an important advantage is that the lens will capture the dimmer meteors.

The Lens Aperture Area versus Angular Coverage Trade
Because meteors appear in random location across the entire night sky, one might think that an all sky camera would pick up the most meteors. But this is not the case. Wide angle lenses mean short focal lengths and short focal lengths have smaller physical lens apertures, so collect less light. Thus, there is a trade between lens technology to collect a lot of light and angular coverage…

Another factor in meteor capture is where to point. If one points closer to the radiant then the angular velocity of a meteor decreases and the longer focal lengths are not impacted as much.

For several years I shot with wide-angle and ultra-wide-angle lens (28mm, 24mm, and 16mm). More recently, I been shooting with 50mm and 85mm lens. Last year, with the 85mm lens I captured one (1) meteor. But the detail was great!

This year I shot with a 50mm lens. This is an old, legacy lens: Nikon 50mm Ć’/1.8 AI manual focus.

We set up the camera on a star tracker, dialed in the settings, and then let it go taking continuous shots at Ć’/2.8, 30 seconds, and ISO 1600. The camera was pointed with the radiant in the lower left corner. Also visible in the composite is Andromeda Galaxy (M31) in the upper right. Meanwhile, we pulled out the camp chairs and leaned back to stare at the sky for a few hours.

We saw a few dozen meteors in about 2-1/2 hours and the camera with its smaller FOV captured considerably fewer. As the Moon rose above the horizon we packed it all away and drove home. Reliable reports indicate that meteor activity picked up considerably in the pre-dawn hours. We were happily asleep at that time.

Perseid meteors (full crop)—2020.
Perseid meteors (full crop)—2020.

The first image is a stack of the handful of shots containing meteors and downsized for this posting. The second image (full-size image), on the other hand, is a full-size crop of two meteors showing how much detail can be found when using a fast lens with a narrow field of view.

Comet C/2020 F3 (NEOWISE)—VIII

Comet C/2020 F3 (NEOWISE) is growing dimmer in the evening sky although is still visible in binoculars. Longer exposures are now necessary to reveal the fan-shaped tail.

Comet C/2020 F3 (NEOWISE) in the evening sky.
Comet C/2020 F3 (NEOWISE) in the evening sky.
Comets C/2020 F3 (NEOWISE), C/2019 U6 (LEMMON), and C/2017 T2 (PANTARRS).
Comets C/2020 F3 (NEOWISE), C/2019 U6 (LEMMON), and C/2017 T2 (PANTARRS).

The second image is a wider view that shows that Comet C/2017 T2 (PANSTARRS) and Comet C/2019 U6 (LEMMON) are also visible albeit both are very small and faint. M53, a globular cluster, and M64, a spiral galaxy, are also visible and labeled. A full-size version of this image (~2.1 MB) is also available.

These images are a stack of five images each 120 seconds at Ć’/4, 85mm, and ISO 400. The shooting location was Sunset Crater National Monument, an International Dark Sky Park.

Lightning at Sunset

It’s been a challenging season for storm photography. First was a late start to the North American Monsoon. And, then, just as it was finally ramping up it shut down quickly. Current model forecasts suggest at least another week until it ramps up again.

This storm eventually produced lightning after sunset.
This storm eventually produced lightning after sunset.
Sunset and lightning north of Sedona.
Sunset and lightning north of Sedona.
Evening twilight colors and lightning.
Evening twilight colors and lightning.

A bit of moisture managed to produce some thunderstorms right around sunset. And there was enough lightning to make it worthwhile to be there and get some photographs.