People in two states took shelter amid wailing warning sirens Sunday as tornadoes touched down in Kansas and Oklahoma as part of an extreme weather system plowing through the nation's midsection.

KFOR via AFP - Getty Images

Damaged structures after a tornado ripped through Wellston, Okla.

The system, which stretched from North Texas to Minnesota, also heaved hail -- dime- to softball-sized -- as well as heavy rainfall. 

Near Oklahoma City, a half-mile-wide tornado was reported, prompting an an unusually blunt alert from the Weather Service: "You could be killed if not underground or in a tornado shelter," the advisory said. 

Around Shawnee, Okla., three large tractor-trailer rigs flipped over, one that had apparently been blown off a highway overpass, NBC station KFOR TV in Oklahoma City reported. 

Across central Oklahoma, where multiple twisters were seen, homes were blown apart and off their foundations with some of the worst damage seen in the Twin Lakes area just outside Wellston, according to KFOR. Power lines were downed and trees uprooted.

Oklahoma Gov. Mary Fallin declared a state of emergency in 16 counties.

St. Anthony Shawnee Hospital in Shawnee, Okla., treated 11 patients, hospital information officer Carla Tollett said. One victim was in critical condition, she said; the remaining 10 were to be treated for minor injuries and released.

Oklahoma's Department of Emergency Management confirmed four injuries in Lincoln County, but no fatalities. Officials were still surveying damage in many areas. Damaged buildings were confirmed in Edmond, Norman, Lincoln County and Pottawatomie County, which declared a state of emergency. 

Residents in downtown Wichita, Kan., were told to seek shelter Sunday afternoon after a tornado was confirmed on the ground – with its presence cloaked by thick thunder clouds and heavy rain.

The National Weather Service in Wichita warned of a large and “extremely dangerous and potentially deadly” tornado late Sunday.  Weather spotters confirmed the tornado 7 miles northwest of Haysville and moving northeast at 30 mph, the Weather Service said.

The tornado later passed south of the city in Sedgwick County in southern Kansas, but rain and thunderstorms continued to batter the area, NBC station KSN-TV in Wichita reported.

Travis Heying / MCT via Zuma Press

A tornado touches down southwest of Wichita near the town of Viola on Sunday.

The warning, which covered downtown Wichita as well as the surrounding area that includes Haysville, was lifted in early evening, KSN reported.

Power lines were down and at least three homes were damaged near Wichita, one with its roof blown off, KSN reported. Authorities said there were no injuries to report.

Other tornadoes were confirmed near Udall and Emporia, and danger remained in many parts of southcentral Kansas with residents told to seek refuge in storm shelters.

At least one massive tornado was confirmed on the ground near Oklahoma City, KFOR reported. The Weather Service reported that that twister was seen by spotters near Luther and was moving east at 30 mph.

The Lincoln County sheriff's office reported damage from three tornadoes that touched down, but the extent of the damage was not immediately known.

The Weather Service's Storm Prediction Center in Norman, Okla., is forecasting tornadoes, large hail and damaging winds over parts of the central Plains into the week.

Low pressure in the Plains states will keep things "very unsettled and stormy" as the week goes on, The Weather Channel reported.

On Monday, the severe storms threat moves down to North Texas and Oklahoma, through northwest Arkansas, southeast Kansas and Missouri into parts of the Upper Mississippi Valley and Great Lakes, according to the Weather Channel. Large hail and damaging winds are possible.

By Tuesday the large system is expected to be moving slowly to the east, from eastern Texas to the southern Great Lakes.

The storms are being generated by a dip in the jet stream combined with moisture moving north from the Gulf of Mexico, Kim Cunningham of The Weather Channel reported on NBC Nightly News.

The danger follows a series of tornadoes that struck northern Texas on Wednesday night, leaving six people dead and dozens injured. One of the twisters was preliminarily classified EF-4 by the National Weather Service, meaning it could have had winds up to 200 miles per hour.

Overall, tornadic activity has been slow this May, typically a bad month for twisters, said the Weather Channel’s Tom Moore.

Reuters contributed to this report.

Large sections of the Plains states came under tornado watches Saturday as a wave of storms swept through.

The greatest threat late Saturday was in eastern Kansas and Oklahoma, weather.com reported, with central Oklahoma seeing a spike on Sunday.

But Weather Channel meteorologist Michael Palmer said the storms on Sunday afternoon and evening were likely to carry a greater chance of tornadoes and the danger will be present into Monday.

The National Weather Service issued a tornado watch for most of western and central Kansas until 11 p.m. CDT, NBC station KSNW of Wichita reported. Early Saturday evening, a Weather Service tornado warning was in effect for an area north of Dodge City, Kansas, that included Ellis, Ness, Rush and Trego counties.

The storms are being generated by a dip in the jet stream combined with moisture moving north from the Gulf of Mexico, Kim Cunningham of The Weather Channel reported on NBC Nightly News (see the video above).

The danger follows a series of tornadoes that struck northern Texas on Wednesday night, leaving six people dead and dozens injured. One of the twisters was preliminarily classified EF-4 by the National Weather Service, meaning it could have had winds up to 200 miles per hour.

Overall, tornadic activity has been slow this May, typically a bad month for twisters, said the Weather Channel’s Tom Moore.

NBC News staff writer Matthew DeLuca contributed to this report.

Related story: Storm warning: Weekend could turn nasty 

A man who donated sperm to a pair of lesbians so they could start a family is now being hounded for child support by the state of Kansas — which refuses to recognize the same-sex coupling.

But William Marotta's attorneys want the now-separated lesbian co-parent to be involved in a lawsuit in which the state claims he is the legal father of a 3-year-old girl.

The state of Kansas contends that Marotta is legally responsible for the girl conceived after he responded to a Craigslist ad placed by the lesbian couple for sperm donation.

Kansas is seeking some $6,000 in back child support.

The ad was placed by Jennifer Schreiner and Angela Bauer more than three years ago with the idea that Marotta, a married mechanic  from Topeka, would not be involved in the child’s life or bear any responsibility for her upbringing.

Marotta even signed a contract waiving parental rights and responsibilities — which he thought absolved him from any financial obligations for the child.

In fact, he didn’t even accept the $50 payment offered from Schreiner, who gave birth to the girl, and Bauer, Schreiner’s partner at the time.

The state of Kansas, however, sees it differently. The Sunflower State contends that the contract is invalid because a Kansas law requires that a licensed physician perform any artificial insemination — which was not the case with Schreiner.

Only Marotta and the birth mother, Schreiner, are party to the suit.

This week, attorneys for Bauer and Marotta asked a judge to reconsider a ruling that keeps Bauer out of the case as a full-fledged participant.

Bauer, they argue, who cares for the girl about half the time and signed the sperm donor agreement at issue, should be fully involved.

“The human beings in this case want all the adults in the case to make a determination for what is in the best interest of the child,” Joseph Booth, an attorney representing Bauer, told NBC News. 

Booth said a recent Kansas high court case, Frazier v. Gouschaal, established that a nonbiological mother of children in a same-sex relationship has the same rights as a biological mother.

“The only basis to prevent Angela Bauer from the full status as a party is that she is female,” Booth wrote.

Benoit Swinnen, Marotta’s attorney, filed a similar motion on Tuesday seeking to make Bauer a “necessary party” or dismiss the case.

Swinnen claims the whole case is political, since neither of the lesbian parents has sought Marotta’s involvement and the money involved is “peanuts.”

“(The state) will do anything to push their traditional notion of families and suppress any nontraditional type of parenting,” Swinnen told NBC News. “It runs so contrary to the way the country is going.”

Swinnen’s Shawnee County District Court filing said Bauer should be allowed to intervene in the case and be recognized as the legal parent of the girl, not his client.

Schreiner as the birth parent has custody of the girl, but according to both attorneys Bauer takes care of the girl during the day with Schneiner caring for her in the evenings. Bauer and Scheiner have even drawn up a parenting plan for the girl, which Booth said, if and when it is approved by a court, would legally resolve issues of custody and financial support.

The state became involved in the case when the couple's relationship fell apart and the two broke up, and one of them got sick. They applied for state health insurance for the girl. The Kansas Department for Children and Families demanded they reveal the name of the sperm donor, which they eventually did, reluctantly.

The state then filed the child support claim against Marotta in October 2012.

Angela de Rocha, the communication director for Kansas’ DCF, wasn’t immediately available to comment on this week's filings, but in January she explained Kansas’ rationale for the lawsuit:

“In cases where the parties do not go through a licensed physician or a clinic, there remains the question of who actually is the father of the child or children. In such cases, DCF is required by statute to establish paternity and then pursue child support from the non-custodial parent,” Rocha said in a statement.

On Tuesday, District Court Judge Mary Mattivi appointed Jennifer Berger, a family law attorney, to represent Jennifer Schreiner.

Related: Hey, sperm donor, don't answer that Craigslist ad!

Kansas lawmakers approved sweeping anti-abortion legislation on Friday that says life begins at fertilization, forbids abortion based on gender and bans Planned Parenthood from providing sex education in schools.

In addition, the measure requires women to learn about fetal development before having an abortion.

The measure now goes to the desk of Republican Gov. Sam Brownback, who opposes abortion, and is expected to sign it.

The House passed the bill 90-30, The Associated Press reported. The Senate approved it by a 28-10 vote, according to Reuters.

Republicans have large majorities in both houses.

"This fulfills the legislative intent to create a pro-life state," Kathy Ostrowski, legislative director of Kansans for Life, told Reuters before the House vote.

Thirteen states, including Missouri, have similar language to the Kansas bill in their laws, the AP reported, citing the National Right to Life Committee.

The Kansas legislation is the latest in a push by national abortion opponents for new restrictions on the procedure. Those limits are seen as a direct challenge to the U.S. Supreme Court's Roe v. Wade ruling in 1973 that legalized abortion.

Late last month, North Dakota Gov. Jack Dalrymple signed the nation’s strictest anti-abortion measures into law. One statute bans abortions as early as six weeks into pregnancy.

An Arkansas law approved over Democratic Gov. Mike Beebe’s veto prohibits most abortions after about 12 weeks of pregnancy.

Abortion rights groups say they will challenge the new abortion laws in court.

Though the Kansas bill defines life as beginning at fertilization, it does not ban abortion from that point.

Reuters contributed to this report.

A deadly snowstorm packing hurricane-force wind pummeled the Great Plains on Monday, the second bout of fierce winter weather there in less than a week. Authorities pleaded with people to stay off the roads.

Wind gusts of 75 mph were recorded at the airport in Amarillo, Texas, and up to a foot and a half of snow was on the ground — the most in at least 110 years. At least one city fire truck was stuck.

“This is a really nasty blizzard,” said Greg Postel, a meteorologist with The Weather Channel.

The storm was being blamed for at least two deaths: In the town of Woodward, Okla., heavy snow caused a roof to collapse, killing one person inside the home, Oklahoma Highway Patrol told NBC News. And in northwest Kansas, a 21-year-old man was killed when his SUV overturned on an icy patch of Interstate-70, according to Kansas Emergency Management officials.

Full coverage from weather.com

National Guard units set out to help drivers stranded along Interstate 40, but the state said that troopers couldn’t get to everyone because of the whiteout. The wind whipped the snow into 10-foot drifts.

Amarillo had 17 inches of snow on the ground at mid-afternoon, threatening its single-day record of 18.1 inches, set in 1934.

Larry Phillips / Southwest Daily Times via AP

City crews remove snow early on Monday in Liberal, Kan., which is under a blizzard warning until Tuesday at midnight.

Authorities closed highways in the Oklahoma panhandle, which was bracing for more than a foot of snow. The University of Oklahoma and Oklahoma State University canceled afternoon classes.

In Kansas, which was expecting up to 2 feet of snow through Tuesday, Gov. Sam Brownback extended a state of emergency from last week.

“This storm has the potential to be more dangerous than last week’s storm,” he said. His advice to drivers: “Stay off the road unless it’s absolutely critical.” For those who had to drive, he suggested packing charged phones and emergency kits.

The storm last week dumped more than 14 inches of snow on Wichita, Kan., its second-highest total on record. Parts of Kansas got a foot and a half, and parts of Missouri more than a foot.

Jamie Squire / Getty Images

Tow-truck driver Tyson House helps trucker Gary Wheeler after his vehicle slid off the road in Greensburg, Kan., during last week's storm.

Joe Pajor, a public works official, told NBC affiliate KSN in Wichita that this storm would create driving conditions “that are basically unprecedented for the traveling public.”

The storm’s reach extended to the Southeast. The National Weather Service said it could spawn tornadoes Tuesday in Louisiana, Mississippi, Alabama, Georgia and the Florida Panhandle.

FedEx said the storm was causing delays for deliveries in 15 states, as far east as Pennsylvania and as far north as Minnesota.

The storm also threatened to dump 6 inches of snow on Chicago through Tuesday.

The same weather system blanketed Colorado on Sunday. About 200 flights were canceled at the airport in Denver, and Gov. John Hickenlooper told non-essential state workers to report two hours late Monday.

Reuters and The Associated Press contributed to this report.

This story was originally published on Mon Feb 25, 2013 4:39 AM EST

Kevin Murphy / Reuters

A sprinkler is in use near Dodge City, Kans., on Nov. 26.

The drought that crippled many communities across the nation last year shows little sign of retreating, and the threat of persistent water scarcity is spurring efforts to preserve every drop.

As the drought of 2012 creeps into 2013, experts say the slow-spreading catastrophe presents near-term problems for a key U.S. agricultural region and potential long-term challenges for millions of Americans.

"Everyone is wondering whether this dry weather is the new norm ... or an anomaly that will soon pass," said Barney Austin, director of hydraulic services for INTERA Inc, an Austin, Texas-based geoscience and engineering consulting firm. "We all hope for the latter, but it's hard to tell."

The signs of distress and the search for answers are most prevalent in the Plains, where historic drought blankets much of Nebraska, Kansas, Oklahoma and parts of Texas.

This month the small Oklahoma farming town of Wapanucka lost water completely when the spring-fed wells the community relies on ran dry. Officials closed the town's school and residents had to do without tap water until the town could run a line to a neighboring water district.

In Texas, state lawmakers are pushing for a $2 billion fund to finance water infrastructure projects as numerous communities face their own shortages. But it won't be soon enough to help rice farmers, who were told this month that there is not likely to be enough water to irrigate their fields this spring.

Meanwhile, in the big wheat-growing state of Kansas, penalties for exceeding water use limits for irrigation were doubled this month and Gov. Sam Brownback has launched a task force to come up with strategies to counter statewide shortages.

"It's going to be dry again this year," said Lane Letourneau, water appropriations manager for the Kansas Agriculture Department. "We consider this a really big deal."

Slideshow: America's farmland baking in drought

Drought conditions plague much of the United States after a summer of scorching temperatures and a lack of rain. The dryness is affecting America's farmland, threatening crops like soybean and corn.

Launch slideshow

Searching for solutions
Water use is already tightly curtailed in many states. Years of low rainfall and high heat - last year was the hottest on record for the United States, according to the National Oceanic and Atmospheric Administration - have diminished surface waters even as population and water demand expand.

As well, agricultural and oil and gas interests are pumping the precious commodity from underground aquifers at a pace that often cannot be matched by natural replenishment.

"Water has been viewed as a basic commodity, a basic right," said Les Lampe, a water expert with consultancy Black & Veatch. "You turn on the tap and water comes out and you don't pay very much for it. That has to change."

Farmers are feeling the pain of water shortages most acutely. After multibillion-dollar crop and livestock losses tied to last year's drought, they fear more losses are coming.

Texas rice growers who depend on the lower Colorado River valley for survival are eyeing the fluctuating levels of two key lakes used for irrigation when river levels are too low.

State officials said this month that without enough rain by spring, rice farmers could be completely cut off from irrigation, jeopardizing about 2 percent of the U.S. crop and about $1 billion for the Texas economy.

"We've got a shortage of water," said Ronald Gertson, a rice grower and chairman of the Colorado Water Issues Committee. "People are going to be both hungry and thirsty before they wake up to this problem."

Forecasts show drier-than-normal weather likely prevailing in the Plains and western Midwest for the next few months at least. But even normal rainfall levels would not be enough to fully recharge resources.

Three to five times more rain than normal is needed in key corn-growing areas that include Nebraska and Kansas, for instance, to ease soil dryness after last summer's drought, according to Don Keeney, an agricultural meteorologist with Cropcast weather service.

Roughly 60.26 percent of the contiguous United States was in at least moderate drought as of January 8, according to a "Drought Monitor" report issued by a group of federal and state climatology experts. Severe drought still blanketed 86.20 percent of the High Plains.

"This drought certainly has gotten people's attention," said Joe Straus, speaker of the Texas House of Representatives. "Regardless of whether it starts raining now or not, long-term water planning is essential. We need to be responsible."

For some, it's already an emergency. Persistent dry conditions in north-central Oklahoma led officials in Payne County to declare a state of emergency this month as the reservoir providing water to nearly 16,000 residents in seven counties fell to record low levels.

The approximately 500 residents of Wapanucka are talking of higher rates to fund a permanent pipeline to a new water source. But running out of water has shown how harsh doing without water can be, said Julie Wallis, Wapanucka's city water clerk.

"We are not going to be the only ones who this happens to," said Wallis. "It's coming."

From the archives, Aug. 2012: Drought: the 'new normal'?

A Kansas man who donated sperm to a lesbian couple three years ago is fighting the state’s demand that he pay child support.

The two women raising the 3-year-old girl say they support the man, who responded to an ad they posted on the Craigslist website in 2009, the Topeka Capital-Journal reported.

The issue of child support arose when the two women broke up, and the couple applied for state services. Workers at the Kansas Department for Children and Families demanded the donor’s name and then filed a child-support claim against him, the newspaper said.

Angela Bauer, one of the mothers, told the Capital-Journal that she and her former partner, Jennifer Schreiner, support the donor, William Marotta, “in whatever action he wants to go forward with” to fight the state's demand.

"This was a wonderful opportunity with a guy with an admirable, giving character who wanted nothing more than to help us have a child," the newspaper quoted Bauer, 40, as saying. "I feel like the state of Kansas has made a mess out of the situation."

When Bauer and Schreiner, the 34-year-old birth mother, reached a deal with Marotta that did not include any payment for his sperm donation, he signed a written agreement that relinquished all parental rights and held him harmless “for any child support payments demanded of him by any other person or entity, public or private ... regardless of the circumstances or said demand,” it said. 

The state argued in court papers that because the insemination wasn’t performed by a licensed physician, the contract was null and void.

When the two women split in 2010, they had eight children, including some they adopted, whom they now co-parent. 

Marotta, a 43-year-old mechanic, was dragged into the dispute when the couple filed for state assistance. The state insisted that they reveal the donor’s identity, saying that if they refused to do so, their daughter would no longer be eligible for health care coverage. The women reluctantly complied, the Capital-Journal reported.

The girl’s birth certificate does not include her biological father’s name, and the Capital-Journal said that he had no contact with the girl, other than receiving occasional email updates from Bauer. Both women adopted the girl, although they had to file for adoption separately because the state does not recognize same-sex unions, the newspaper said. This means that the state also cannot collect child support from same-sex parents.

"More and more gays and lesbians are adopting and reproducing, and this, to me, is a step backward," said Bauer, who formerly supported the family financially but is no longer able to work due to a "serious illness." "I think a lot of progressive movement is happening currently in the world as far as gays and lesbians go. Maybe this is Kansas' stand against some of that."

The Capital-Journal could not reach Marotta for comment and the Kansas Department for Children and Families declined to discuss the case, citing privacy laws.

This isn’t the first time states have demanded child support from sperm donors. But in most of those cases, the sperm donor was known to the birth family – usually a man who was friendly with a lesbian couple and who agreed to help them out.

Court rulings vary
Sperm donors who donate through a sperm bank are typically protected by state parenting shield laws. But in less straight-forward cases, courts have differed on whether the men should pay up.

A Massachusetts court ruled this year that a Nigerian immigrant had to pay child support for twins conceived through artificial insemination a year after he and his wife had separated, the Patriot Ledger reported.

And In Vermont, a man who donated sperm to a female friend was required to pay child support because he maintained a relationship with the children.

Explained one of the mothers to The Associated Press in 2007: "Part of the decision came down because he was so involved with them. It wasn't that he went to the (sperm) bank and that was it. They called him Papa."

In New York, a married doctor agreed to donate sperm to a young resident and her partner in the late 1980s, only to be asked 18 years later for child support, the New York Post reported.

His undoing was sending money and cards to the child, which he would sign, “Dad” or “Daddy.” The biological father’s name was also on the birth certificate.

But in Washington state, the Court of Appeals ruled in 2004 that a donor can’t be required to pay child support unless he and the mother have signed an explicit contract.

And in Texas, an appeals court ruled in favor of a former policeman who donated sperm to a woman he had been formerly connected with. He had paid thousands of dollars in child support for twins until the court ruled in his favor.

When the lawsuit was filed in 2008, the man told McClatchy: "I was totally blown away. I was already married and had moved on with my life."

NBC's Isolde Raftery and The Associated Press contributed reporting. 

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