Last week another tornado moved across northern Arizona. The damage produced by this tornado was confined to a small area and was nothing like the tornado outbreak of 06 October 2010.
What makes this tornado interesting is where it occurred. The tornado formed just west of the San Francisco Peaks and then moved up the west flank of Humphreys Peak. Damage was isolated along the early portion of the path at around 9000 feet. As it moved up the mountain, damage increased in intensity and coverage with the peak damage occurring near 9800 feet. Farther up the mountain isolated damage continued until the tornado dissipated near 10500 feet.
The worst damage occurred as the tornado crossed the Humphreys Trail just a short distance from the trail register. In the first few days after the event travel along this section of the trail can best be characterized as challenging. Climbing over and under downed trees — and around others — certainly slows the hiking pace.
This is not the highest elevation tornado of record. That belongs to a tornado that occurred in the Sierra Nevada mountains a few years ago with evidence of damage at elevations above 12000 feet.
The limited damage inflicted upon the mountain might never have been noticed if it had not passed over a heavily used hiking trail. Now that’s serendipity. Or bad luck.
Nobody saw the tornado so all we have to go on is the radar data. And according to that information the event occurred between 5:25 and 5:35 pm on 14 September 2011.
The North American Monsoon is bringing thunderstorms to the southwest United States including northern Arizona. You would think that with almost daily thunderstorms it would be easy to shoot great images of lightning and thunderstorms. Well, not always…
One of the characteristics of the rainy season in the higher elevations of northern Arizona is that as the storms develop in the late morning or early afternoon it quickly becomes overcast so that it is difficult to see the individual storms. It is equally difficult to photograph lightning because it is often raining over large areas obscuring the view of the lightning.
So I was particularly pleased when we had two days in a row in which I was able to photograph lightning and actually see the thunderstorms. The lightning was photographed in Sunset Crater National Monument overlooking the Bonito Lava Flow; the mountain that it is striking is O’Leary Peak. There is a fire lookout station at the summit of the peak and I’m certain they get their fair share of close bolts.
The following day proved equally photogenic. This thunderstorm was photographed in late afternoon and is quite dramatic with mammatus clouds visible from the anvil region of the storm.
The North American Monsoon (NAM) is in full swing across the southwestern states and the daily showers and thunderstorms present many opportunities for dramatic lighting and lightning.
Earlier this week I traveled to the south rim of Grand Canyon National Park hoping to get some sunset images with storm clouds hanging over the canyon. Well, there certainly were clouds — and there wasn’t much of a sunset. The backup plan was to photograph lightning. On this count, the storms didn’t disappoint. There was a storm to the west and I was able to point the camera across the lines of cliffs and rock faces that were already falling into deep shadow in the late twilight. And off in the distance was a great flash of lightning.
A few days later I tried once again to capture twilight lightning — this time at Sunset Crater National Monument. A storm developed in early evening and moved to the northeast over the lower terrain of the Painted Desert in the Little Colorado River Valley.
In the foreground can be seen the Ponderosa Pine trees at the higher elevations in the Monument; in the middle distance are some of the many cinder cones that are a part of the San Francisco Volcanic Field; in the far distance are the lower elevations of the Painted Desert.
With the typical NAM lasting through early September there should be plenty of opportunities for more dramatic lightning photographs.
It’s been an interesting spring as the La Niña conditions of this past winter continue to abate. One of the characteristics of this diminishing pattern has been for low pressure systems to drop southeastward from the eastern Pacific and west coast and then across the southwestern states. Springtime low pressure systems routinely move across the southwest and bring strong winds to Arizona and these systems have been quite normal in that respect, that is, it’s been very windy.
But they have also brought the core of the low pressure system farther south than is typical and across Arizona. The result has been a combination of below normal temperatures and above normal rain along with snow in the higher elevations.
We had three days of snow last week — but only trace amounts fell across the area — and now we are having a real bona fide snow event. A few inches of snow have accumulated at elevations above 7000 feet.
Will this be the final event of this winter-like spring? Or will we see snow again? The record books show that snow isn’t rare in May at these elevations — and snow in June has happened on a number of occasions, too.
We’re all looking forward to spring finally arriving before the calendar says summer.
The weather across much of the country has been very dramatic the past few days with snow storms, ice storms, strong winds, and brutal cold. Across Arizona we experienced exceptionally cold weather as the Arctic air mass settled in across the area. Strong northeast winds at the surface and aloft helped to drive the cold air across the Rocky Mountain barrier and deep into the southwest.
The northeast winds also created some fantastic wave clouds over the San Francisco Peaks, located to the north of Flagstaff. Normally, strong southwest winds roll across the Peaks and the best wave clouds are located to the northeast but this wind reversal resulted in a reversal of the wave clouds as well.
Even more interesting were the clouds that were forming just below the tops of the peaks. Strong winds from the northeast drove cold air into the Inner Basin on the east side then up and over the top of the peaks. As the air ascended thin wispy clouds would form. Just as quicky the air descended on the southwest slopes and the clouds evaporated.
The rapidly changing clouds and detailed structure were fascinating to watch. A time-lapse movie clearly shows this incredible dance of the clouds as it moves across the Peaks.