2 p.m. Saturday
The National Weather Service has issued a tornado watch for much of Oklahoma as storms dump hail and heavy rain on the state.
National Weather Service forecaster Daryl Williams says nickel- to quarter-sized hail was reported Saturday near Lawton and Anadarko in southwestern Oklahoma.
One to two inches of rain has fallen across southeastern Oklahoma since midnight, while rainfall totals are up to an inch in northwestern Oklahoma.
Williams says the storms will continue into Saturday night, but that the tornado threat will likely end about 9 p.m. or 10 p.m.
The weather service has issued a flash flood warning until 4:30 p.m. for central Oklahoma and until 4:15 p.m. in southeastern Oklahoma.
Tornado watches were also issued in eastern Colorado, western Kansas and North Texas.
As the threat of more storms in North Texas loomed, crews are working to reopen a rail line after flooding washed away the tracks.
The washout caused four engines and 13 cars to derail on Friday near Valley View, about 50 miles northwest of Dallas; four crew members had minor injuries.
BNSF Railway spokesman Joe Faust said Saturday that bad weather could hamper efforts to replace the tracks, but that they could reopen by Saturday night. Amtrak passenger trains were being rerouted.
Storms brought heavy rain and quarter-sized hail to parts of southwest Oklahoma on Saturday afternoon, but the greatest chance of potentially dangerous weather in the Great Plains loomed later in the day.
The National Weather Service says there's a risk of severe thunderstorms Saturday — including possible tornadoes and large hail — in parts of western Kansas, western Colorado, and a large part of Oklahoma and parts of North Texas.
"After 9, 10, the tornado threat will diminish," National Weather Service forecaster Daryl Williams said of Oklahoma's threat, "but that doesn't necessarily mean the severe weather or rain will diminish."
But the threatening skies stretched beyond the Plains states, as twin weather systems stretching from the Carolinas to California produced an unseasonably early tropical storm in the Atlantic and a late-season snowstorm in the Rocky Mountains. Tropical Storm Ana's forecast track is expected to go near the coasts of North and South Carolina on Sunday.
Meanwhile, up to 5 inches of snow was possible in the Nebraska Panhandle this weekend, and parts of South Dakota could receive between 12 to 24 inches of snow, according to the weather service.
Heavy rains on Friday night caused some flooding in Oklahoma. Officials in Shawnee, about 40 miles east of Oklahoma City, were monitoring the levels of Granada Lake, which was at risk of breaching a dam and flooding about 25 homes. Shawnee received 2.95 inches of rain since Friday morning, according to the Oklahoma Climatological Survey.
Earlier this week, powerful storms rumbled through the southern Plains, producing more than 50 tornadoes and dropping 7.1 inches in Oklahoma City on Wednesday — the third-heaviest rainfall for any day on record dating back to 1890, state climatologist Gary McManus said.
David Wheeler and his family retreated underground to a small shelter several times this week. Two years ago, a top-of-the-scale twister tore a miles-long path through the Oklahoma City suburb of Moore and turned Wheeler's son's school to rubble. The family now regularly drills on what to do if the skies turn ominous.
"We've done some dry runs before the spring. I made the kids go down there by themselves, and we've done the same thing with me, the wife and the kids, all together," Wheeler, a fifth-grade teacher whose family has survived two deadly tornadoes, said Friday.
Wheeler and his family are not the only ones who sought extra protection after the 2013 tornado that killed 24 people, including seven children who died in an elementary school. In the two years since, the city has issued more than 3,000 storm shelter permits. City officials estimate that about 40 percent of homes in Moore now have shelters, spokeswoman Deidre Ebrey said.
Associated Press writer Sean Murphy contributed to this report.