Extreme drought conditions have developed across southeast and south-central Georgia. Another week with little or no rain and temperatures in the 70s and 80s have led to worsening drought conditions statewide.

Extreme drought now grips the southeast and south-central Georgia counties of Appling, Atkinson, Bacon, Berrien, Brantley, Brooks, Camden, Charlton, Clinch, Coffee, Cook, Echols, Glynn, Jeff Davis, Lanier, Lowndes, Pierce, Thomas, Ware and Wayne.

The drought is severe in Ben Hill, Bryan, Chatham, Colquitt, Evans, Grady, Irwin, Liberty, Long, McIntosh, Montgomery, Tattnall, Telfair, Tift, Toombs and Wheeler counties.

The rest of south Georgia is experiencing moderate to mild drought conditions.

In northwest Georgia, Bartow, Catoosa, Chattooga, Dade, Fannin, Floyd, Gilmer, Gordon, Haralson, Murray, Paulding, Pickens, Polk, Towns, Union, Walker and Whitfield counties are in severe drought.

Moderate drought conditions are found in the north and central Georgia counties of Banks, Carroll, Cherokee, Clayton, Cobb, Coweta, Dawson, DeKalb, Douglas, Fayette, Forsyth, Fulton, Gwinnett, Habersham, Hall, Harris, Heard, Henry, Lamar, Lumpkin, Meriwether, Muscogee, Pike, Rabun, Rockdale, Spalding, Stephens, Talbot, Troup, Upson and White.

The other north Georgia counties are in a mild drought.

Drought categories are based on many indicators. Some of these are rainfall over the past one, three, six and 12 months and soil moisture, stream flow and groundwater levels.

Extreme drought conditions are defined as those we expect once in 50 years, based on the multiple indicators. Severe drought conditions are those we expect once in 20 years, while mild drought conditions are once in 10 years.

Rainfall deficits for Jan. 1 through April 23 include Athens at 4.73 inches, Augusta 4.87, Columbus 5.04, Savannah 6.17, Macon 6.71, Plains 7.19, Brunswick 7.48, Tiger 8.64, Atlanta 8.74, Alma 9.09, Tifton 9.78, Blairsville 10.81 and LaFayette 12.22.

The U.S. Geological Survey reports daily record-low flows for April 23 in southeast and south-central Georgia. The record lows for the day were on the Ochlockonee River near Thomasville, the Alapaha near Alapaha and at Statenville, the Suwannee at Fargo and the Satilla near Waycross and at Atkinson.

Record low flows for the same day were reported in north and central Georgia on the Ocmulgee River at Macon and near Jackson, the Alcovy above Covington, the Oconee near Athens, the Flint near Griffin, the Oostanaula near Rome and at Resaca, the Coosawattee near Ellijay and the Conasauga at Tilton.

Little if any relief from the drought is anticipated in the foreseeable future.

If Georgia has normal weather through the summer, the soils will continue to dry out, and stream flows and groundwater levels will continue to decrease. Water levels in reservoirs and farm ponds are expected to continue to lower over the next several months.

The entire state remains under the level-2 outdoor water-use schedule. Outdoor watering is allowed only from midnight to 10 a.m. on Sundays, Tuesdays and Thursdays at odd-number street addresses and on Mondays, Wednesdays and Saturdays at even-number addresses. It's banned all day on Fridays.

Local water authorities may further restrict outdoor watering.

Get updated drought information at www.georgiadrought.org. The state drought Web site includes information on how to deal with the drought.

Get updated weather information at www.georgiaweather.net. This University of Georgia network has 71 automated weather stations statewide.

(David Stooksbury is the state climatologist and a professor engineering and atmospheric sciences in the University of Georgia College of Agricultural and Environmental Sciences.)