OKLAHOMA CITY (AP) — The Oklahoma Climatological Survey says a 120-day period from late fall into early spring is the driest such period on record for central and southwestern Oklahoma.

Associate State Climatologist Gary McManus said Thursday that the average rainfall for central Oklahoma from Nov. 24 to Wednesday was 2.42 inches, 5.88 inches below normal. Southwestern Oklahoma received .76 inches of rain during that period, a deficit of 5.09 inches.

The statewide average of 3.45 inches for the past 120 days ranks as the third-driest such period ever.

McManus says the U.S. Drought Monitor has expanded its "extreme drought" designation from southwestern Oklahoma up through Oklahoma County. He says some reservoir levels are low, including Lake Altus, which is at 48 percent capacity.

He says the drought also may extend the wildfire season.