The Supercell

It’s a beast. Supercell thunderstorms can produce copious hail, torrential rainfall, strong winds, fierce downdrafts, and even tornadoes. While they are the least common type of thunderstorm, they are the most ferocious.

All thunderstorms require lift, forcing air upwards to the point of becoming positively buoyant. Also, instability (atmospheric energy) is required for the air to rise. Finally, moisture (typically mid-60s dew point) is necessary. So, what’s the additional ingredient needed for a supercell?

It’s wind shear. Wind shear is caused by differences in wind speed and direction over a relatively short distance in the atmosphere.  Shear can induce a storm’s updraft to begin rotating, forming a mesocyclone, the signature feature of a supercell.

From Mesocyclone Diagram

Mesocyclones begin with horizontal rotation. Winds from two different directions and speeds (the red arrows) at two different altitudes create shear, imparting rotation (the green arrow) to a parcel of air. Then, a strong updraft (the blue arrow) begins to tilt the rotating parcel of air progressively vertically, creating a deep, tilted rotating updraft (the mesocyclone).

From Wikipedia

In an ordinary thunderstorm, rain and cold air falling through the updraft chokes off the updraft, killing the storm.

Tilt pushes the hail and rain ahead of the updraft. The unimpeded mesocyclone can continue to fuel the supercell for hours.

Tornado Alley

Tornado Alley is the hotbed of supercell and tornado activity. This part of the country hosts the perfect convergence of the jet stream, cold dry air and wind from the north, warm dry air and wind from the southwest, and warm moist air and wind from the southeast.

Shear, lift, instability, and moisture are abundant in the Spring and Summer. Tornado Alley is now centered further east due to climate change, and winter storms are more common.

From https://kristanwevvie.pages.dev/pmllvwy-tornado-alley-2024-ymvvzcp/

The Shot

As you know from my last Friday Photo, I’ve been away chasing storms for 11 days. On June 2, my first day, we began chasing storms in the Wyoming/Nebraska area.

At 5:30 pm we set up near Merino, Colorado. Next to me on this storm was experienced storm chaser and timelapse expert Tom Trott from London, England.

His timelapse of this Friday Photo’s supercell approaching our position is at  https://youtube.com/clip/UgkxvlWNYSfLD3UndHgR9a1yOtd5TKQ0YbAR?si=8P9oW2tBAcGDWzKv It ends just as we needed to “bug out” due to approaching hail, rain, and high winds. Thanks for sharing, Tom!

Of the many pictures I took of this beautifully structured supercell, this one with a lightning bolt is my favorite. While it didn’t produce a tornado, standing in awe of nature’s fury is an equally rewarding experience.

Thanks for looking,

Chuck Derus

Zenfolio | Chuck Derus

The Quieter Side

Have you been to the Grand Canyon? Given its popularity, I’m guessing that most Friday Photo followers have visited the Park. Last year, it was ranked as the third most-visited National Park, behind Great Smoky Mountains National Park and Zion National Park.

The South Rim attracts almost all the visitors coming to view the Grand Canyon’s display of 1.8 billion years of geology. Fewer than 2 percent of the Park’s nearly 5 million visitors a year drive the additional five hours and 212 miles to the North Rim.

The North Rim (“the quiet side”) of the Grand Canyon is a wholly separate experience. It is a more remote, rugged and individual opportunity to see what John Wesley Powell (geologist, U.S. Army soldier, explorer of the American West, and second director of the U.S. Geologic Survey) described as “ledges and cliffs where the soaring eagle is lost to view before it reaches a summit.”

The North Rim, unlike the South Rim, allows you to see all the way down the mile-long slit in the earth to where the Colorado River runs. One thousand feet higher, the North Rim offers the three best comprehensive views of the Canyon: Toroweap, Point Sublime, and Cape Royal. Point Imperial is another impressive viewpoint.

Point Imperial

This is the highest point on the entire rim of the Grand Canyon. At an elevation of 8,803 feet, it’s the northernmost boundary of the Park.

From Point Imperial, visitors have breathtaking views of the Painted Desert and the eastern end of Grand Canyon. This is the area where the canyon transforms from the narrow gash of Marble Canyon to the more open and dramatic "grand" canyon. Layers of red and black Precambrian rocks add contrast and color.

Mount Hayden is the dominant structure visible from the Point. This 8,362-foot summit is one-half mile to the Southeast. It towers 5,000 feet above the bottom of Nankoweap Canyon.

It’s named for Charles T. Hayden (1825–1900), an Arizona pioneer influential in the development of the Arizona Territory. He is known as the "Father of Tempe,” and established Arizona State University.

The summit is composed of cream-colored, cliff-forming, Permian Coconino Sandstone caprock. This sandstone is the third youngest of the strata in the Grand Canyon, deposited a mere 265 million years ago as sand dunes. Below this lies reddish, slope-forming Permian Hermit Formation, which in turn overlays the Pennsylvanian-Permian Supai Group.

I’m not sure the height is conveyed by my photo. For scale, here’s an image of two climbers atop Mount Hayden from John Boyd shot this photo of us on the summit of Mount Hayden

The Shot

I was at the North Rim in August of 2023 with Steve Horne, Allan Fischer, and John Tarsha, all members of Naperville’s Photogenesis Camera Club. Our objective that morning was a Point Imperial sunrise image.

We were alone that morning. Steve and I climbed over the railing for a better view on a ledge below. Allan and John opted for a more secure perch on the viewing platform. Just as the sun was illuminating Mount Hayden with the multiple atmospheric layers in the background, I knew I had my image.

Afterwards, it was back to the North Rim Lodge for coffee and a hot breakfast.

Steve Horne and me after sunrise, courtesy of Allan Fischer

Wish me luck; I’m in the field chasing storms over the next two weeks. The next Friday Photo will be June 20.

Thanks for looking,

Chuck Derus

https://cderus.zenfolio.com/

Up North

To Minnesotans, "Up North" is more than a direction. It’s a way of life. Northern Minnesota is a land of lakes, forests, cabins, resorts, and campsites that evoke pleasant memories of family and friends. Mosquitoes, not so much.

Some say that Up North began in the 1920s when the logging industry left Northern Minnesota. To keep the economy growing, the hospitality industry began marketing the region as a place to fish, boat, sunbathe and swim. And automobiles made getting there easy.

Geographers call it a perceptual region. It's a sense of place brought on by something you see or imagine. Suzanne Kindler says it well.

"It's the place people go to escape, a place made of cabins, pine trees and lakes. But no matter how far you drive, there's no sign to say, ‘You've Arrived,’ so just follow your heart until you find...your special place that brings peace of mind, as you breathe in the air and unwind, your cares are all left behind. It's no mystery where the Northwoods start...When you arrive ‘Up North’ you'll know it... in your heart."

Growing up in Minneapolis, I remember going Up North on multiple occasions as a child and young adult. Swimming, canoeing, fishing, and water skiing in lakes surrounded by pine trees are some of my fondest memories.

Later, my parents treated our young family twice to vacations at Ruttger’s Bay Lake Lodge near Deerwood, Minnesota.

My parents Leo and Emily Derus, daughter Caroline, wife Christine, and son John at Ruttger’s in June 1984

It’s the resort we now visit each summer with our children and grandchildren.

July 2023 at Ruttger’s. Back Row: Jim Cook, Caroline Derus Cook, Me, Christine, Blake Weis, Lisa Derus, Cathy Derus, John Derus. Front row: Ben and Josh Cook, Leo Weis, Alex, Cecilia and Monica Derus. A photo today would also include Dottie and Frankie Weis.

The Shot

The North Shore of Lake Superior is among my favorite places Up North. So, when I have a photographic excuse to return, I take it.

In August of 2023 I was in Grand Marais, Minnesota. While there, I drove to nearby Devil Track Lake for sunset. As the colors in the sky intensified and the loons began to call, I knew in my heart that I was Up North.

Thanks for looking,

Chuck Derus

https://cderus.zenfolio.com/