Monday's wet weather closed roads and snarled traffic on Interstate 35. It was also expected to drop temperatures into the 40s overnight.

Two wrecks involving semitrailer trucks driving during heavy downpours closed the highway for hours at various times.

A jackknifed 18-wheeler blocked two northbound lanes of I-35 near Stassney Lane in South Austin about 12:15 p.m., police said. No injuries were reported, but the rig leaked fuel, prompting cleanup by a hazardous materials team. And in Williamson County, north of Jarrell, an 18-wheeler dumped a full load of building materials, including lumber, onto the interstate, forcing traffic to be rerouted along the frontage road for about two hours. No one was injured in the wreck, which was reported at 8:35 a.m.

Bob Rose, a meteorologist with the Lower Colorado River Authority, said the Austin area got about 2 inches of rain over about six hours. In parts of Williamson and Travis counties, rain totals exceeded 3 inches.

Low water crossings across Central Texas closed because of flash flooding. The area that received the most rain was just north of Lake Buchanan, just west of Burnet, where about 5 inches of rain fell, Rose said.

Rains that started in September have lifted Travis, Williamson and Blanco counties and parts of Bastrop County out of the worst drought category — exceptional, Rose said. But much of Central Texas remains in a moderate drought. Hays and Caldwell counties and other parts of Bastrop County remain in severe drought, the second-worst category.

"The supply in aquifers is still very low," Rose said, "but the vegetation in the area is ... nice and green."

The rains have raised Lake Travis about a foot to 643.41 feet, Rose said. The lake could rise another foot, as runoff collects.

Today's weather should warm to the low 70s under sunny skies, Rose said.

The next chance for rain could be as early as Wednesday, and that storm is expected to have heavier rainfall and the potential for severe weather.