July 27, 2009 © Thomas J. Kollenborn. All Rights Reserved.
According to
legend and myth the great The “Thunder God” roars during the summer
months. Many of us do not find this hard to believe, if we have
experienced a violent thunderstorm in the Apache Junction area during
the summer. There are basically two types of storms that occur in our
area.
The first storm type brings the central
mountain area of Arizona its winter rains. These winter storms result
from the general cyclonic patterns that move across the United States
every ten days or so. These storms originate in the Aleutian Low in the
Gulf of Alaska, and can dump enormous amounts of precipitation on
Arizona below the Mogollon Rim if their course is altered by the jet
stream. These storms will generally last four or five days with steady
rainfall. This type of weather can be identified with the solid unbroken
overcast resulting from Stratus clouds. These are what we call our
winter storms and they are usually not violent in nature.
The second storm type is known as the
Monsoons. These storms bring massive thunderstorms with heavy showers,
lightning and sometime devastating winds called micro-bursts. During the
summer months most of the storms over central Arizona and the eastern
portion of the Superstition Mountain Wilderness result from warm, moist
air flowing in from the Gulf of Mexico and the Sea of Cortez. This air
moves across Texas, New Mexico and Mexico. Mountains force the moist
warm air upward forming clouds. These clouds release their moisture as
they rise. This is known as orographic lift. The massive anvil-shaped
thunderhead clouds that form over Superstition Mountain from July to
September normally combine both orographic lift and convectional
activity.
Convectional storm clouds result from
the rapidly rising and expanding of warm moist air and rapidly falling
cold moist air. Uneven heating of the earth’s surface causes
convectional activity in the atmosphere.
Lightning can be caused by the
attraction of unlike electrical charges within a thunderhead. The rapid
movement of ice and water molecules, going up and down in a thunderhead
cell, creates friction that results in an enormous amount of static
electricity being produced. A single lightning discharge can produce
about 30 million volts at 125,000 amperes. A discharge can occur in less
than 1/10 of a second. The results of a lightning strike can be
horrific.
The rapid rising and falling of warm and
cold moist air also creates violent bursts of energy. This type of
activity results in micro-bursts. These micro-bursts can develop winds,
momentarily, up to 200 mph. As the clouds build and combine they form
massive anvil-shaped thunderheads called cumulonimbus clouds. These
clouds are massive static electric generators dispersing lightning and
creating violent winds. These summer thunderstorms are extremely violent
and can be very dangerous.
It is these giant thunderheads that
dominate the sky above Superstition Mountain during the monsoon season.
The lightning produced by these storms can be spectacular. According to
most sources the safest place during a lightning storm is in an
automobile. Don’t make yourself part of a lightning rod during an
electrical storm by standing near a lone tree or on a high point. The
use of your telephone during a violent lightning storm could be your
last conversation. The same is true connecting to the Internet during a
lightning storm. Standing near or in a swimming pool is asking to meet
your maker. Boating on a lake during a lightning storm is certainly
risking your chances of living to a ripe old age. Common sense needs to
prevail during our violent thunder and lightning storms.
Most Arizona monsoon storms are
associated with two other dangerous factors: flash floods and dust. A
thunderstorm can dump three to five inches of rain over a small area in
an hour and create a massive flash flood. A flash flood near Payson in
the 1970’s claimed twenty-two campers along Christopher Creek. Many
years ago I witnessed a four-foot wall of water that roared down Hewitt
Canyon claiming a couple of trucks, horse trailers and animals. These
flash floods result from heavy isolated downpours of rain in the
mountains. There is often very little rain at the site of a flash flood.
Huge dust clouds are often associated
with Monsoon storms in the desert. Local weather reporters are often
referring to Monsoon generated dust storms as Haboob, named for the
Egyptian dust storms that blow in from the Sahara or Sinai Deserts in
North Africa.
Dust storms are extremely dangerous to
automotive traffic along our state’s highways and freeways. Extreme
caution should be used during these storms. It is recommended during
these storms to pull as far off the highway as possible and turn your
lights off. While waiting for the dust storm to blow over don’t rest
your foot on the brake pedal. Your taillights or brake lights might
attract reckless drivers wanting to follow you in the storm.
It is not difficult to see why the early
Native Americans held Superstition Mountain with such awe. If you have
ever witnessed a violent electrical storm over the mountain you can see
why. We can partially explain the phenomena today with modern science,
but the early Native Americans could only look to their Gods for an
explanation. The storms were certainly caused by their “Thunder God”
with all his might and fury.
We, as late arrivals, should still respect the awesome power of the “Thunder God.”
