Lightning is a hazard almost everywhere in North America, even in deserts that receives only a few inches of rain a year. The danger is highlighted by this “Storm Danger” sign on the original Navajo Bridge (former U.S. Route 89A) in Marble Canyon, Arizona. Despite infrequent rain there, storms can produce prodigious lightning.
The sign’s warning about when “lightning is present” should be stated more assertively. A clear, storm-free sky does not mean a visitor is safe from lightning. A thunder burst could be tens of miles away and hidden from view beyond a ridge, yet its lightning can travel great distances horizontally before striking the earth — or a person standing on a bridge.
Waiting until the lightning is “present” could be too late. If lightning can be seen or thunder can be heard — go indoors or into a hard-top vehicle.
Haboobs and Lightning
At other times, the approach of an electrical storm makes itself very conspicuous. Massive dust storms called “haboobs” can be accompanied by intense lightning. Phoenix, Arizona and surrounding areas have had several dramatic haboobs already during this year’s monsoon season and the National Weather Service reports 4,000 lightning strikes during one recent storm.
Fortunately, the lightning safety recommendations state above are also helpful in dealing with a haboob. The National Weather Service recommends that, “When Thunder Roars, Go Indoors”. Staying inside and closing windows will help reduce the health hazards and irritations associated with the extremely fine dust in a haboob.