7:10 a.m. CDT

The National Weather Service is warning of new flooding across much of Oklahoma, where creeks, rivers and lakes remain swollen from spring showers.

Meteorologist Michael Scotten, in Norman, says two bouts of bad weather should hit the state Thursday. Morning rainfall will likely dwindle before noon, but a system moving in after 2 p.m. could spawn thunderstorms, hail and tornadoes.

Some parts of the state could see as much as 3 inches of rain. The greatest threat for severe weather this afternoon is in western Oklahoma, where tennis ball sized hail and tornadoes are possible.

The service has issued a flood advisory for central Oklahoma and a flash flood watch for most of the state. Oklahoma City is in its wettest month ever recorded with 19.5 inches of rain.

___

6 a.m. CDT

While the barrage of deadly thunderstorms that hit Texas this week has tapered off, many cities remain in danger, and officials are warning about possible flooding from rain-swollen rivers.

In suburban Houston, subdivisions along the San Jacinto River are expected to flood.

In Wharton, located southwest of Houston, residents in 300 homes on the west side of the city have been asked to evacuate due to the predicted rise of the Colorado River. And in the North Texas town of Horseshoe Bend, about 250 residents were asked to evacuate their homes, as the Brazos River swelled toward its flood stage Thursday.

The death toll from the storms and flooding has climbed to 21 — 17 in Texas and four in Oklahoma. Houston alone had seven storm-related deaths.