Exchange: Flagstaff’s monsoons both replenish and destroy

August 10, 2019

FLAGSTAFF, Ariz. (AP) — Summer monsoons, those brief yet intense afternoon showers that can cool the temperature by 20 degrees and overflow canals in an hour or two, are inextricably linked to Flagstaff, every bit part of the town’s character as the verdant forests, the chugging locomotives and the outdoor recreational options.

Yet, Flagstaff also seemingly has a complicated relationship with this seasonal weather pattern — especially now, in the wake of the Museum Fire, in which the specter of intense monsoons along the “burn scar” could result in dangerous and damaging flash flooding in town.

That’s the maddening thing about this type of weather: it can both replenish and destroy; nourish and negate; cool and ignite.

There’s a curious dichotomy at work. Monsoon help firefighters battle blazes — the well-timed rain in late July aided the tamping down of the Museum Fire — but the lightning that often accompany storms also start more fires than those determined to be human-caused. Monsoons provide life-giving nourishment to the flora in the area, yet the severity (hail, for instance) and duration can wipe out one’s garden in a single swoop. And monsoons refill aquifers and give ranchers and farmers — most bereft of irrigation options — much-needed water to grow the grasses that feed livestock. Yet, closer to town, too much water, accumulated too fast, can wash out homes and businesses.

So, you can perhaps understand the mixed feelings some townsfolk may have about monsoons, which this summer, according to the National Weather Service, started late.

If you’re in your car cursing the heat, and suddenly the temperature drops to a pleasant 65, you have reason to cheer. If you’re hefting sandbags in Sunnyside and fretting about water damage, you aren’t so welcoming. If you are a firefighter battling a major blaze, monsoons give assistance, but you may have to hustle to another part of the mountain to deal with a lightning-caused fire.

Mostly, though, Flagstaff’s relationship with monsoons is far more love than hate. Actually, there’s a third emotion at play: acceptance.

Kurt Meyers, a former longtime Flagstaff meteorologist, was fond of saying that two words define weather in the area: “extremes and surprises.” Rancher Michael Macauley, whose family has worked the land here since 1884, likes to quote his stoic grandfather, Lilo, who opined, “There are two kinds of weather here, dry or wet. So whatever we get is ‘normal.’”

True, many in town have come to terms with monsoon life.

Take Gabriel Hood, owner of Lion Heart Roofing. Every summer and fall, he gets considerable business from people whose roofs have been damaged by hail, yet he says his customers aren’t blaming the monsoon for the damage. “Most take it pretty well,” he said. “It’s a different country up here. Different way of thinking. People deal with it.”

Ambivalence can take hold. For instance, Susan Madden, president of the Coconino Master Gardener Association, gets positively giddy when the afternoon rains come. But she also volunteers for the community emergency response team, and saw the anxiety wrought on people by the possibility of post-fire flooding from monsoon activity.

“It’s too bad,” she said, “the monsoon has to bring these flash-flooding situations. If it could just rain nice for about two hours, then come back tomorrow and do the same thing, that would be wonderful.”

Firefighters engaged in containment work, in general, don’t deal in bargaining with Mother Nature, said U.S. Forest Service spokesman George Jozens.

“We play the hand we’re dealt,” Jozens said during a recent interview. “We had overnight rain, so, today, (firefighters) didn’t have to go in to the mountain until later in the morning. They got to eat a hot breakfast for a change and take their time. So it’s not a horrible thing, especially when you get a soaking rain overnight. Any time you get a soaking rain - not a torrential downpour - it helps.”

But .

“Monsoons bring lightning, which causes more fire starts and puts firefighters in danger,” Jozens added. “When monsoons come, we leave high ground. Most are in their vehicles waiting for what happens. We’re not going to take the chance to be out there no matter whether it’s one bolt or a hundred. That’s the natural state of our forest in northern Arizona. We actually need lightning to start the fires to burn out the fuel that’s on the ground so we don’t have a catastrophic fire.”

Indeed, experts say fire caused by monsoon lightning strikes can be good. What’s not so good is how, in a major incident such as the Museum Fire, the water runoff can threaten property below and also raise health concerns about the watershed.

Sheila Murphy, a research hydrologist with the U.S. Geological Survey in Colorado, said a downside to monsoons is the potential of having potentially unhealthy materials wash into communities.

“The bad news is, after a fire, how hard it rains is a big factor in what your water quality after that is going to be,” Murphy said. “The intensity can be high in Arizona. The flood risk is obvious, but when the water’s running off, it takes with it that soil and ash and brings it quickly into waters. There’s organic carbon that comes from the ash and soil, which is a problem. If you treat water with chlorine, you can often get a byproduct that’s harmful to humans.

For Macauley, the rancher, there can never be “too much rain” from monsoons.

“Water is my livelihood,” he said. “Moisture here is essential, and the water runoff is part of this part of the world we live in. You don’t have livestock if you don’t have grasses. These summer storms basically water your warm-season grasses both for (livestock) and wildlife.”

If you sense some tension between those dependent on the rain — the harder, the better — and those who relish monsoons in moderation but fret about the adverse consequences, that’s to be expected.

But, as Susan Lamb, a naturalist, author and Flagstaff resident since 1983, said, “the tension is mostly in waiting for it.”