AP Science Writer
WASHINGTON (AP) - The unusually hot dry weather that has gripped the nation will not let up its stranglehold over the next few months, federal weather forecasters said Thursday.
And that means the heartland's "flash drought" will linger at least until around Halloween and even spread a bit farther north and east.
The National Oceanic and Atmospheric Administration's outlook for August through October shows that nearly every state likely will have hotter than normal temperatures. Much of the Midwest is likely to be drier than normal, too.
"It certainly is grim news for us in Illinois and other parts of the Midwest," said Illinois state climatologist Jim Angel. "I kind of have given up hope for short-term relief."
New figures released Thursday show that the percentage of the country now suffering from drought edged up from nearly 51 percent last week to more than 53 percent this week; the chunk of the country experiencing severe drought or worse rose in one week from 31 percent to 35 percent. Experts call it a flash drought because it developed in a matter of months, not multiple seasons.
"It's really unpleasant," said drought specialist Kelly Helm Smith at the National Drought Mitigation Center in Nebraska. She said relief "is not on the radar that I'm aware of."
For the Midwest, forecasters don't see any improvement until at least past October. In fact, if the weather phenomenon El Nino forms as predicted, that means even more dry weather next winter for the Midwest and North, said seasonal forecaster Dan Collins of NOAA's Climate Prediction Center in Maryland.
NOAA's forecast for just the month of August indicates a high probability for little rain for all or parts of 15 states that are the epicenter of the drought. That region encompasses Illinois, Indiana, Missouri and Iowa and the states generally surrounding them.
All told, 42 states or parts of them have been hit by the drought. A NOAA map shows it stretches from California east to Ohio and from Texas north to Minnesota. Tiny pockets of drought also dot the East, including much of Georgia and South Carolina.
The forecast for the next three months would push the drought farther north into Minnesota, North Dakota and Michigan, and farther east into Pennsylvania, New York and West Virginia. But in the Southwest, especially Arizona and New Mexico, and to a lesser degree Colorado and Utah, the drought will ease a bit. And the eastern drought pockets are also likely to improve a bit.
NOAA is also forecasting more triple-digit hot weather for several days starting Saturday for much of the Midwest from Kansas and Nebraska to Indiana and Michigan, with temperatures about 12 degrees hotter than normal. And that will make the drought even worse, forecasters say.
One of the main problems is the heat and lack of moisture are in a feedback loop. The ground is so dry that there's not enough moisture in the soil to evaporate into the atmosphere to cause rainfall. And that means hotter, drier air.
Illinois' Angel said the best chance for significant rain is going to come from the remnants of tropical storms or hurricanes that push into the Midwest, something that doesn't happen often.
"That's how desperate we are," Angel said.
NOAA's latest seasonal drought outlook: www.cpc.ncep.noaa.gov/products/expert_assessment/seasonal_drought.html
NOAA's Climate Prediction Center: http://www.cpc.ncep.noaa.gov/
U.S. Drought Monitor: http://www.droughtmonitor.unl.edu/
Seth Borenstein can be followed at http://twitter.com/borenbears
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