Weather whiplash is the perfect descriptor for what’s on tap for the Southwest. Things have been hot and dry since this winter, but they could get wet and wild this weekend as the remnants of Hurricane Bud drench Arizona and parts of New Mexico.
Bud is currently churning over the eastern Pacific and is expected to make landfall as a tropical storm in Baja California. It’ll eventually weaken into a remnant low pressure system. Arizona as a whole could see an average of about three-quarters of an inch of rain through Sunday, which weather.us meteorologist Ryan Maue tweeted would equal 15 trillion cans of 12 oz. Budweiser (because get it, it’s Hurricane Bud).
At this point, exact rainfall totals in specific locations can be a challenge to predict with the storm still hundreds of miles away. Michael Crimmins, a climate researcher at the University of Arizona, told Earther a shift in just a few dozen miles either way “can leave some areas with inches of precipitation and other nothing.” He said Friday is when things could start to come into clearer focus.
Any rain would put a small dent in the drought, though it could also cause flash flooding as runoff cascades down dry slopes and over hardened soil. And it’s almost certainly not going to make up the precipitation deficit currently plaguing the region.
The entire state of Arizona is mired in drought with three quarters of it in the worst two categories of drought, according to the latest U.S. Drought Monitor. New Mexico isn’t far behind, with 99 percent of the state in drought save a sliver of its southern edge.
The dry conditions have raised the risk of significant fires, and a number are already burning. These include the biggest fire in the U.S. currently ablaze in northeast New Mexico and a number in Colorado to the north, according to the National Interagency Fire Center. The fire danger is so great that portions of national forests and parks in the Four Corners region are now closed to visitors to reduce the risk of an errant campfire or cigarette butt sparking a conflagration.
Rain from Bud’s sad remains could quell fire risk in the near-term, but it could also pose additional risks down the road.
“If it does materialize, the precipitation will definitely help, but I am concerned about a long break in precipitation after this,” Crimmins said. “We could spur a lot of summer vegetation to start growing and it may run headlong into several weeks of hot and dry conditions if the monsoon season precipitation doesn’t materialize later this month.”
The current drought conditions can be tied back to a very dry winter. Arizona had its sixth-driest November-April on record while New Mexico had its third-driest. Relentless heat has cranked the drought into overdrive, with the states respectively having their warmest and second-warmest November-April on record. That’s sapped what little moisture there was out of the ground and vegetation and hurt reservoir storage.
Droughts of various strength have ebbed and flowed in the Southwest for the past 20 years. Climate change is likely to dry out the region even further, while heat is projected to exacerbate those conditions, raising the specter of megadroughts that could last a decade or longer.
Crimmins said the looming storm shows it “can be feast or famine” for precipitation in the Southwest. And famine may become far more common as the world warms.