The country, meanwhile, is heading into another warm season with a higher percentage of the continental US experiencing dry conditions than it did last year. Federal drought statistics released April 9 show that in each of four out of five severity categories, abnormal dryness or drought covers about 12 percent more of the continental US today than it did this time last year. The fifth category, exceptional drought, covers only 2 percent of the nation, but that's double the level for this time last year.
The current drought forecast, which covers April 4 to June 30, shows drought conditions easing from portions of northeast Texas through western Wisconsin and Minnesota. Forecasters expect modest improvement into the Central and Northern Plains. But from central and western Texas north through the Rocky Mountain states to California and eastern Oregon, drought is expected to continue or expand its reach.
It's unclear how well that will hold up. Where seasonal forecasters had a decent bead in advance on the drought that covered the US southern tier in 2011, last year's event was distinct and unforeseen, the researchers say.
Indeed, while much attention has focused on what the new study has to say about global warming's impact on the drought, the study's main intent was to look for features in the drought that seasonal forecasters could have predicted a season or more in advance.
"To speak about climate change, which has altered the odds of something, is not the same as speaking about the predictability of an event" such as last summer's drought, Martin Hoerling, a researcher who focuses on climate variability at NOAA’s Earth Systems Research Laboratory in Boulder, Colo., said at one of two briefings on the report on Thursday.