The weather system that spawned deadly overnight tornadoes in Texas could bring beneficial rain to metro Atlanta on Thursday, but probably will offer little relief to drought-plagued areas or South Georgia firefighters battling wildfires.

The National Weather Service said there's a slight chance that Thursday afternoon's thunderstorms could be severe across the northern half of Georgia.

Six people were killed Tuesday night when a tornado hit the Texas border community of Eagle Pass, destroying an elementary school and more than 20 homes.

The Texas storms developed along a cold front that should bring showers and thunderstorms to North Georgia on Thursday.

The forecast for metro Atlanta calls for a 20 percent chance of showers and thunderstorms Wednesday night, with lows around 60 degrees.

The chance of showers and thunderstorms will increase to 60 percent by Thursday afternoon, when highs will be in the upper 70s.

A 40 percent chance of rain is predicted for Thursday night, diminishing to 20 percent on Friday, the Weather Service said.

The weekend outlook calls for mostly sunny skies Saturday and Sunday, with a 20 percent chance of overnight showers Saturday night.

In south Georgia, where wildfires have been burned more than 50,000 acres near Waycross and the Okefenokee Swamp in the last 10 days, the chance of rain is only 20 percent Thursday night and 30 percent on Friday, the Weather Service said.

State climatologist David Stooksbury said Tuesday that extreme drought conditions have developed across southeast and south-central Georgia, as well as in 17 counties in the northwest corner of the state.

"Extreme drought conditions are defined as those we expect once in 50 years. . . based on rainfall, soil moisture, stream flow and groundwater levels," Stooksbury said.

Most of metro Atlanta is experiencing moderate drought conditions, Stooksbury said.

Rainfall deficits for the year across the state range from 4.73 inches in Athens to 8.74 inches in Atlanta and 12.22 inches in Lafayette.

The entire state is under a "level 2" outdoor watering schedule that allows water use only from midnight to 10 a.m. on Sundays, Tuesday and Thursdays at odd-numbered addresses and on Mondays, Wedenesdays and Saturdays at even-numbered addresses. Outdoor water use is banned all day on Fridays.