HOUSTON (AP) -- This week's record rainfall in Texas eased the state's drought and swelled rivers and lakes to the point that they may not return to normal levels until July, scientists said Thursday.
Just weeks ago, much of the state was parched with varying levels of drought. But the same drenching rainfall that paralyzed parts of Houston and swept away a vacation home with eight people inside also offered relief from a long dry spell.
Many cities were still in danger of flooding as heavy rain from earlier in the week poured downstream, pushing rivers over their banks.
"There's so much water in Texas and Oklahoma that it's going to take quite a while for those rivers to recede," said Mark Wiley, a National Weather Service meteorologist in Fort Worth, Texas.
If normal amounts of precipitation return, rivers will probably drop to average levels by the Fourth of July, he said.
"Six months ago, we were dying for this stuff," he said. "And now we're saying, `Please, please stop.'"
On Wednesday, the Houston area got a respite from the rain, but by Thursday runoff from earlier in the week had lifted the San Jacinto River above flood stage, and it kept climbing. Nearby residents watched the high water with alarm.
"We came back out here today to get a few of our things that we had parked by the road," said Brian Harmon, who lives in suburban Kingwood. "The water keeps rising and rising. We didn't want to lose anything else."
Harmon's home had up to 2 feet of water. Nearby streets had water rushing over them.
"It's very stressful," he said. "I'm very tired of it."
About 60 miles southwest of Houston, the mayor of Wharton asked residents to voluntarily evacuate about 300 homes because of the predicted rise of the Colorado River.
And in the rural Parker County community of Horseshoe Bend, some 40 miles southwest of Fort Worth, officials asked people in 250 homes to flee from the Brazos River.
By early Thursday, Parker County Emergency Management spokesman Joel Kertok said the Brazos had almost crested, but officials had no immediate reports of flooded homes and were monitoring the situation.
He said the river, which has a flood level of 21 feet, was at nearly 24 feet.
This week's storms and floods in Texas and Oklahoma have left at least 21 people dead and at least 10 others missing.
In Miami, President Barack Obama said the flooding should serve as a reminder of the need to make the nation more resilient against natural disasters. He said climate change is affecting both the pace and intensity of storms.
"The best scientists in the world are telling us that extreme weather events, like hurricanes, are likely to become more powerful," Obama said during the first visit of his presidency to the National Hurricane Center.
"When you combine stronger storms with rising seas, that's a recipe for more devastating floods," he said.
In Central Texas, search crews continued looking for the eight people feared dead after the swollen Blanco River smashed through Wimberley, a small tourist town between San Antonio and Austin, over the Memorial Day weekend. Authorities there are concerned that more rain forecast for the region could hamper the search.
The Hays County emergency management coordinator, Kharley Smith, said more rain could shift debris fields and complicate efforts to find entangled victims.
A portion of the San Jacinto on Thursday was at nearly 53 feet, about 4 feet above flood stage, said Kim Jackson, a spokeswoman for the Harris County Flood Control District.
A neighbor was helping Joy Rizzi build a concrete barrier Thursday at the rear of her home north of Houston near the San Jacinto. She was hoping the barrier would prevent debris carried by the rising river from damaging her home. Rizzi planned to move her car to higher ground, but she was staying put.
"I'll stay because I don't want to leave my home," she said.
Chuck Bayne was among those who decided to follow authorities' advice and leave his North Texas home in Horseshoe Bend. On Wednesday, Bayne, owner of the Brazos RV Resort, headed to his second home in Arlington.
"Everybody on the river is leaving, except you have a couple dozen who aren't leaving," he said. "They're afraid of looters, and some are just plain stubborn."
Farther west, about 20 homes flooded after waters rose at Lake Leon. Fire Chief Darrell Fox said officials had asked for voluntary evacuations of 100 to 150 homes around the lake, which is 100 miles southwest of Fort Worth.
In Wharton, the Colorado River is expected to crest at about 45.5 feet, nearly 7 feet above flood stage, by either late Friday or early Saturday.
"We've made a tour of the area, and a lot of the people have taken heed of our warnings and are moving out," Wharton Mayor Domingo Montalvo Jr. said Thursday. The city has opened a shelter, but so far only one person is staying at the facility.
Lozano reported from Houston and Robbins from Wimberley.
Associated Press writers David Warren, Jamie Stengle and Terry Wallace in Dallas; John L. Mone in Wimberley; and Joshua Replogle in Houston contributed to this report.
Follow Juan A. Lozano on Twitter at www.twitter.com/juanlozano70 .