BOISE – After eight years of nearly constant drought, weather experts in Idaho are betting on a little girl to turn things around. “La Niña” is the Spanish name for the climate pattern in which unusually low surface sea temperatures dominate the equatorial Pacific Ocean, sending storms this way.
This year, La Niña is finally beating back her brother, El Niño, the warm Pacific Ocean weather pattern that sank Idaho back into drought this past winter following a one-year respite in 2006. That year, El Niño briefly went into hiding, scientists said.
With La Niña’s return for the first time since 1999, federal weather watchers predict the Pacific Northwest, including Washington, Oregon, Idaho and parts of Montana, will experience colder, wetter weather than normal.
“The odds are tilted that way – if you were going to Las Vegas to bet on it,” said Jay Breidenbach, a National Weather Service hydrologist in Boise. “That usually results in above-normal snowpack in Idaho. It doesn’t always work out that way, but that’s what the climate prediction center is showing.”
Idaho, like many of the 36 states now beset by impending water shortages because of a combination of rising temperatures, drought and population growth, could use the help. About a quarter of its $45.9 billion economy comes from agriculture and tourism, so farmers and resort officials across the state follow weather with keen interest.
Still, there’s also a flip side: As La Niña brings wetter, colder weather to the Northwest, the Southeast Climate Consortium warns the weather system could result in drier, warmer weather for Florida, Alabama and Georgia.
In Idaho, La Niña may already be making herself felt, Breidenbach said.
Since the latest 12-month period for precipitation measurements began on Oct. 1, every one of Idaho’s 19 river basins stretching from the Canadian border in the north to Utah and Nevada in the southeast has gotten above-average rain or snowfall, according to Natural Resources Conservation Service records.
Last year’s numbers were dismal: For the water year that ended Sept. 30, a single river basin – above Oakley, in Idaho’s deep south – received more precipitation than average. The Little Wood Basin near Sun Valley had just 70 percent of average.
Isolated pockets were even worse, as the city of Idaho Falls got just 44 percent of its average 12-inch rainfall.
In July, Boise’s average high temperature of 98.6 degrees Fahrenheit was more than 9 degrees above average, making the month the warmest on record in Idaho’s capital city.
The consequences were severe: Two million acres of Idaho burned in wildfires in 2007, the most of any state – even after last week’s California conflagrations, according to the National Interagency Fire Center in Boise. Utilities like Idaho Power Co. set electricity usage records as residents flipped on air conditioners, driving up power costs. And the Idaho Department of Water Resources declared drought emergencies for some two dozen Idaho counties and cities.
As Sherrie Hebert, the National Weather Service hydrologist in Pocatello, surveyed the parched eastern Idaho and southwestern Montana landscape where she grew up, she said it’s clear the drought is changing the scenery.
It’s been so dry for so long, newcomers likely don’t know anything else, she said. “It’s starting to seem ordinary to me,” Hebert said.