The same weather pattern that helped to cause drought in California and South America this year may migrate east into the central U.S. during the Northern Hemisphere’s summer, a climate forecaster said.
A strong upper-atmosphere ridge anchored over Alaska and in the southeast South Pacific near Indonesia suggest that drought conditions from Texas to Iowa may intensify from June to August after a brief period of above-normal rain from May to early June, according to Scott Yuknis, the lead forecaster with Middleboro, Massachusetts-based Climate Impact Co.
There will be “beneficial late spring, early summer rains in the northern Great Plains,” Yuknis said in an e-mail. “Otherwise, central U.S. drought strengthens this summer. Spring rains will be too spotty to ease central U.S. drought.”
A clash between cold air in the northern U.S. and warm weather in the south may bring extreme weather, Yuknis said. Freezing temperatures in May will threaten wheat crops in the Great Plains, Yuknis said. June rain may help to boost soil moisture from North Dakota to Illinois, while hot weather in July and August will increase crop stress.
About 22 percent of the Great Plains was rated in moderate-to-extreme drought on Feb. 11, while 17 percent of the Midwest was rated in drought, data from the U.S. Drought Monitor show.
Cooler-than-normal water temperatures in the northern Pacific Ocean and warm waters across the northern Atlantic Ocean increase the risks for hot, dry weather from Texas to the Ohio River Valley this year, Yuknis said. The center of the excessive heat this year will be Oklahoma and spread over parts of Texas, Kansas, Missouri and Arkansas.
Source - http://www.businessweek.com/
