While rain and snow have ended droughts across much of the U.S. this year, conditions have gotten worse in Arizona, further extending a dry streak that began in 1996.
A weak monsoon and meager rain in the months before and after turned rangelands brittle and allowed the summer wildfire season to linger through autumn.
And in the high country, the soil is so parched that it likely will soak up some of the spring snowmelt before the water can flow into rivers and reservoirs. That will in part blunt the effects of El Nino, a shift in ocean temperatures that can produce wetter winters in Arizona.
Enough water is stored from past years to protect Phoenix from shortages no matter what happens this winter, but the rest of the state faces a bleaker outlook that could include conservation measures or even water hauling in some places if weather patterns don’t change.
“We really are sliding toward pretty serious drought conditions by spring,” said Michael Crimmins, a University of Arizona climatologist who helps monitor drought for the state. “We’ve been working to keep everybody focused on drought, to get ready for an event like this. Well, here it is.”
Back in February, drought seemed just a memory for a few weeks, at least in Phoenix. Salt River Project dumped water from its reservoir system into the normally dry lower Salt River after a series of early storms filled Roosevelt Lake to the limit allowed by federal regulators.
But the overflow owed more to the previous winter, which produced a gusher of melting snow. This one ended below average in runoff production, just like most of the winters since 1996, when the current string of dry years began. When the lower Salt dried up again, so did everything else.
Just 2.78 inches of rain has fallen at Sky Harbor International Airport since Jan. 1, more than 4 inches below the 30-year average for mid-November. No measurable rain has fallen since Sept. 5, setting Phoenix on course to break the record, set in 2002, for the driest year on record.
Similar deficits exist elsewhere: Flagstaff has recorded 7.92 inches this year, almost 12 inches below normal. Tucson has received 5.24 inches, less than half its normal through mid-November.
The numbers represent short-term drought on their own, but added to the precipitation totals for the past decade and a half, they could signal a deepening of a more serious dry streak. Unless conditions shift dramatically in December, 2009 will end as one of the driest years in the past 14 years.
If the winter fails to deliver at least average amounts of rain and snow, the short-term effects will grow more visible by spring. Rural areas will suffer first. Water shortages will develop and intensify as the weather warms. Ranchers will find less forage for livestock. Forest and range conditions will ratchet up the wildfire risk.
Most at risk are small towns with wells, such as Pine, Strawberry and communities in southern Arizona. But Flagstaff needs a good winter to refill Lake Mary, an important source of drinking water, and to replenish springs and wells on the city’s outskirts.
“The change in drought status this year has been unprecedented,” said Susan Craig, who heads the state drought office. “We saw things get worse on 12 watersheds, and our precipitation statewide was well below 70 percent of average. It’s much worse than it’s been for a long time.”