want the forecast now? >> yes. >> it looks dry. rain would be the worst thing. and it looks dry. >> cold enough at night so the ice will stay. >> thanks for joining us. on the broadcast tonight, ferocious freeze. half the country now caught in the grip of the coldest air yet. emergency rooms are packed, schools shut down. and tonight we've got a spectacular view high above the frozen niagara falls, a bird's-eye view only a drone can deliver. superbug scare at a major american hospital. two patients are dead and many more are being warned they may have been exposed. we'll take a closer look at a serious problem in hospitals all across this country. what really happened? the shocking case of road rage, a mother gunned down. tonight, a suspect in custody after a dramatic standoff with police. and, what we eat. re-writing the rules from everything from coffee to cholesterol. some surprising new changes.

"nightly news" begins now. from nbc news world headquarters in new york, this is "nbc nightly news." reporting tonight, lester holt. good evening. tonight the coldest weather of the season is settling in across much of the country's eastern half. this winter of extremes has already exacted a heavy toll. dozens of weather-related deaths from ohio to tennessee where this week at least 15 people have died, a third from hypothermia. right now the siberian express is spreading across the east bringing single-digit and below-zero temperatures from the great lakes to the northeast. and even record lows in florida. let's start in nashville with nbc's gabe gutierrez. >> reporter: relentless, snow, ice and now subzero temperatures some 40 degrees below average have much of the country frozen over. in michigan new video of an officer somehow surviving this crash over the weekend.

in tennessee, a dash cam captured another close call. a worker clearing a crash scene barely managed to jump out of the way of a pickup truck. have you ever seen this many sliding injuries here? >> not over this brief period of time. >> reporter: vanderbilt children's hospital in nashville has treated more than 60 kids for sledding-related injuries. >> when an unprotected brain and skull and head, you know, hits either stationary or moving solid object, you're going to get a head injury. >> reporter: overnight 911 dispatchers here got calls reporting what may have been ice quakes. very unusual in the south. >> i don't have it with a big boom outside. >> yes. >> ice quakes happen when you have water that seeps under the soil into the rocks. it freezes quickly. when that ice expands it actually pops. >> reporter: in florida farmers are rushing to protect their crops. more record lows are expected tomorrow. negative 9 in pittsburgh, 2 below zero in evansville, indiana. charlotte will top out at 8 degrees. and a frigid 14 in atlanta. in newton, massachusetts firefighters are digging out

nearly 2,000 hydrants. >> it's a real problem for us not only to fight the fire in the cold and the snow, but just to move around and get good access. >> reporter: with a low at negative 8, chicago shattered a record set in 1936. baggage handlers at o'hare. >> it starts blowing about 20 30 miles an hour then it feels like it's 30 below, 40 below. >> reporter: tonight, in upstate new york a weather phenomenon. a geyser has frozen into an ice volcano, as a historic arctic blast continues to barrel through. more than 2 million people including those here in nashville are now under yet another winter storm warning. lester, more snow and freezing rain is expected here tomorrow. >> just keeps coming. gabe, thank you. dylan dreyer has one of the most spectacular views on the planet tonight. at niagara falls, almost completely frozen over. dylan, how does it feel out there? and what are we all looking at ahead? >> reporter: lester, it looks pretty, but it feels brutally cold. and it is going to remain cold

with records likely tomorrow morning. take a look at the cold weather warnings we have from the great lakes to the northeast, stretching all the way down into southern florida. by tomorrow morning wind chill advisories for miami where it will feel like it is about 22 degrees. it will feel like it's about 30 below across the northeast. and on friday morning we'll see some improvements down south, but we're still looking at that brutal cold from the mid-atlantic right up into the northeast for friday morning. now, we do have another ice storm in areas hard hit from the last storm, from little rock to memphis we could see accumulating ice tomorrow. we are going to see that spread into virginia, north carolina as we go into saturday with some snow. again, in the mid-atlantic up into new england. snowfall accumulations should be light, just a couple of inches. but we are looking for more ice back through most of tennessee where we could see up to a quarter of an inch of ice. lester, coming up we are going to show you an absolutely spectacular view from high above niagara falls on the canadian side. a bird's-eye view that only a drone can deliver. >> looking forward to that, dylan, thank you.

another big story people are keeping a close eye on tonight. another deadly superbug being reported at a major hospital in los angeles. two patients confirmed to have it are now dead. five others are confirmed exposed and many more are being warned they may have been expose exposed as well. we have two reports on this story. we want to begin with nbc's hallie jackson in l.a. what are you hearing? >> reporter: lester, we know nearly 200 people have received phone calls from ucla over the last 48 hours letting them know about that potential exposure to this superbug. the head of the cdc calls it a nightmare bacteria that's mutated so much even the most powerful antibiotics can't fight it. health officials say if it infects the bloodstream, it can be deadly up to half the time. in a late afternoon news conference, reassurance from you can la officials. >> we've implemented a whole new sterilization process that's much more stringent. >> reporter: 179 patients are getting home testing kits from the hospital to see if they caught the same superbug that infected five people and

possibly contributed to the deaths of two others. >> our heart goes out to the people who were involved and the patients who passed away as a result of this infection. >> reporter: the bug's been traced to two medical instruments used in a complex kind of endoscopy called ercb. it's when doctors use a device called the duoendoscopy. to examine the upper intensen. but bacteria can get trapped at its tip making it hard to clean. >> this is really the perfect storm. you have an instrument that on the whole is difficult to completely disinfect. and at the same time you have a bug that has become more and more resistant to antibiotics. >> reporter: dr. andrew ross works at a seattle hospital where more than 30 patients recently infected with cre and other large outbreaks have happened in chicago and pittsburgh. >> this is serious. this is not something that is just business as usual. >> reporter: and a cre infection can be painful. barb thom is still getting treatment after catching the bug five years ago from a different surgery. >> i was experiencing fevers and not feeling well.

it's hard to get rid of it. i can't. >> reporter: in a new report the fda says over the last two years a reported 135 patients had problems with bacterial infections from dirty scopes. that's out of about a million procedures. the agency says for most people who have this specialized endoscopy, the benefits outweigh the risk of infection. hallie jackson, nbc news, los angeles. >> reporter: i'm dr. nancy snyderman at jackson memorial hospital in miami, where reminders are everywhere that cleanliness counts. >> it's really about accountability. everybody plays a role. >> reporter: kevin andrews is vice president of patient safety. his job, make health-care-associated infections a thing of the past. in a hospital where you have your most vulnerable, your doctors and your nurses are really the people who spread infection. >> that is absolutely correct. and so one of the things we've really worked hard on is really putting together a hand hygiene program. >> reporter: but it's not just about clean hands. keeping medical equipment and instruments meticulously

disinfected could be the difference between life or death. the cdc estimates that on any given day about one in 25 hospitalized patients has at least one health care associated infection. there were about 722,000 of those infections in u.s. acute care hospitals in 2011, resulting in an estimated 75,000 deaths. in random testing, researchers at the university of michigan health system found that even when technicians follow instructions, often the instrument still contain debris. who's most at risk for these bacterial infections? the elderly, patients spending a lot of time in hospitals, especially in the critical care units and those with catheters or on ventilators. the fact that we're still talking about tens of thousands of people every year getting hospital-acquired infections is an indictment frankly, of how

poorly we're doing. so for hospitals and clinics it means strict protocols and then doctors and nurses and everyone else following the rules. lester. >> all right, dr. nancy, thanks very much. now to another story that a lot of folks are talking about. a firestorm over what the former mayor of new york city said about president obama. politics can be a rough business, and everyone's fair game even the leader of the free world. but when rudy giuliani went before a room of donors and told them that the president of the united states doesn't love his country, his own country, it set off a war of words. nbc's andrea mitchell is covering the fallout. >> reporter: it all started with the way the president talked about islam at his counterterrorism summit. >> no religion is responsible for terrorism. people are responsible for violence and terrorism. >> reporter: republicans and some tabloids pounced. but former new york city mayor rudy giuliani took it to another level. at a dinner with wealthy republican donors last night saying, "i do not believe -- and

i know this is a horrible thing to say -- but i do not believe that the president loves america. he doesn't love you. and he doesn't love me. he wasn't brought up the way you were brought up and i was brought up through love of this country." a statement that drew such sharp responses giuliani backed down, sort of, on fox today. >> he's a patriot, i'm sure. what i'm saying in his rhetoric i do hear him criticize america much more often than other american presidents. >> reporter: and other republicans, potential presidential candidates, like louisiana governor bobby jindal agreed with rudy giuliani. wisconsin governor scott walker also at the giuliani dinner didn't disagree. >> the mayor can speak for himself. i'm not going to comment on what the president thinks or not. he can speak for himself as well. i'll tell you i love america. >> reporter: democrats have sailed the comment. >> what the republican party really wants to be taken seriously, now is the time for its leaders to stop this kind of nonsense. enough! >> reporter: the white house twitter machine went into overdrive. soon the # obama loves america was trending. but it was also used sarcastically by the president's critics.

andrea mitchell, nbc news, washington. the defense has rested in the trial of the man accused of killing "american sniper" chris kyle. a forensic psychologist took the stand today. he testified that the defendant, eddie ray routh, seen in police dash cam video, suffered from schizophrenia and actually believed he was acting in self-defense when he shot kyle and kyle's friend chad littlefield. a tense standoff in las vegas ended with the capture of a suspect in a deadly case of apparent road rage that shocked the nation. a mother of four was shot and killed after police say she took her armed son out looking for the driver who allegedly cut her off in traffic. when police finally caught up to the suspect, as nbc's miguel almaguer reports, he did not come quietly. >> reporter: the tense standoff lasted over an hour. las vegas police in a quiet neighborhood arresting this 19-year-old eric noush, wanted in connection to the road rage

death of 44-year-old tammy meyers. the suspect's vehicle caught on surveillance tape, may have helped lead investigators to his home. >> the real takeaway here is that the suspect involved in the killing of mrs. meyers is in custody and off the streets. >> reporter: meyers was taking her daughter home after giving her driving lessons when the road rage incident occurred. the mother of four dropped her off at home and picked up her 22-year-old son who was armed. after finding the suspect, the suspect tailed the meyers home where he and her son exchanged gunfire. meyers was shot in the head. >> she didn't deserve this. i did what i had to do to protect my family. >> reporter: today, police made the arrest only one block away from the meyers' home while her husband watched it all unfold. >> you made my wife look like an animal, and my son. there's the animal, a block away! are you happy? >> reporter: tonight, grief, disbelief and many unanswered questions.

miguel almaguer, nbc news, los angeles. the explosion at an exxonmobil plant south of los angeles is already causing a jump in the price of gasoline. wholesale gas prices climbed six to ten cents in california following yesterday's blast, which injured four workers. the refinery accounts for a large percentage of california's oil processing. the cause of the blast is under investigation. the nation's largest retailer, walmart, announced today that it's giving a pay raise to hundreds of thousands of its employees. for years walmart has taken heat from labor groups over how much it pays its workers. today's move may be an indication that walmart was worried they'd seek their paychecks elsewhere. here's nbc's anne thompson. >> reporter: after ringing up a stronger than expected holiday season, today walmart said it would share the bounty raising wages for a half million employees. >> today we're investing in them

and we want them to know how important they are. >> reporter: walmart will boost its minimum wage in this country to $9 an hour in april for 40% of its workforce, almost $2 above the federal minimum wage. the move comes after years of protests by those workers complaining of low wages and poor treatment by america's largest retailer. now walmart faces increasing competition for these workers. ikea, gap, aetna and other big companies are a step ahead already paying more to keep hourly employees. >> it's likely that walmart and other companies are increasing wages because they have to because the labor market is not as bad as it was a few years ago and now it's becoming a more competition labor market. >> reporter: there is also political pressure. seven states, plus the district of columbia, already have a minimum wage of $9 or more. and new york and minnesota will do the same later this year. for walmart's hourly workers, the boost in pay is a boost in confidence. >> very exciting.

everybody's just smiling. it's just really great. >> reporter: after some tough years, finally a reward for the people walmart says are vital to running a good business. anne thompson, nbc news, new york. we've got a lot more to tell you about tonight. what to eat, what to avoid in your diet. re-writing the rules for a lot of foods we love. and a surprise about cholesterol. also a rare peek behind the curtain drama at "snl"'s 40th anniversary bash. why eddie murphy refused to be part of a very famous sketch.

welcome back. as we said there's news tonight about many of the foods we love to eat part of the new do itary recommendations on the way we thing about cholesterol. here's nbc news medical contributor dr. natalie azar. >> reporter: today's recommendations for new dietary guidelines are a clear signal we need to change what's on the menu. two-thirds of american adults are overweight or obese and 117 million have chronic diseases tied to a bad diet and lack of exercise. the government panel examines what's good for us to eat, and there are few surprises. but for the first time the committee made some new recommendations. coffee, for example, okay to drink three to five cups a day. meat, don't eat as much red and processed meats, but lean meats can be a part of a healthy diet. and cholesterol -- and this is a surprise. the old guidelines suggested no

more than 300 hill la grams of cholesterol a day. that's about 1 1/2 eggs a day. the new recommendations say cholesterol is not considered a nutrient of concern. research tells us eating cholesterol-rich foods doesn't necessarily translate into high blood cholesterol levels. lester, i think one of the biggest messages to come from this particular report is for viewers to understand the distinction between foods that are rich in cholesterol and nutrients but low in saturated fats. those things are good for you such as eggs, shellfish like shrimp and lobster, or meats like liver. we're still recommending however, that you watch your intake of cholesterol and saturated fat-rich foods like butter, ice cream, bacon. those kinds of things can clog the arteries and lead to higher risk for cardiovascular disease. >> this is not a free-for-all. and eat everything with cholesterol. >> absolutely not. >> dr. azar, thanks very much. we're back with a category 5 storm moving ashore. australia bracing for natural disaster.

australia is bracing for not one but two tropical cyclones making near-simultaneous landfall including one that's a category 5, winds approaching 130 miles an hour as it moves ashore on the queensland coast where evacuations are well under way. many were asking after "saturday night live's" 40th anniversary special why eddie murphy didn't appear in a sketch. turns out "snl" wanted him to, according to former cast member norm macdonald, who says murphy was asked to appear in the "celebrity jeopardy" sketch as bill cosby, who now faces multiple allegations of sexual assault. ultimately macdonald said murphy was uncomfortable with the idea. in a statement, cosby said he applauded murphy's decision. president obama's declared three new national monuments including chicago's pullman district, site of a victory of african-american labor organizers that helped lead to the civil rights movement in the 1950s and '60s. the other new monuments are browns canyon in colorado and a

site in hawaii used as an internment camp for japanese p.o.w.s and japanese americans during world war ii. when we come back, one of america's natural wonders like you have never seen it before. "nbc nightly news" is brought to you by voya financial. changing the way you think of retirement.

as we promised earlier in the broadcast, you may have seen the majesty of niagara falls, but you've never seen it quite like this. tonight, we've got a breathtaking look high above the frozen falls, a view you could only get by sending up a drone. once again, here's dylan dreyer. >> reporter: soaring hundreds of feet over niagara falls, a spectacular sight. frigid air brought in via the siberian express has encased the falls in ice, drawing a surge in visitors from all corners. >> just amazing. you know, winter wonderland. >> reporter: temperatures along the u.s./canadian border haven't gone above freezing this month, transforming what is actually a collection of three waterfalls from just about every angle. >> to see it on this scale, it's really alive. >> reporter: behind the falls what should be a view of gushing water now a wall of ice.

>> everything around you is frozen here. and you can see the water rushing underneath snow and coming through little ports. it's just really neat. >> reporter: the falls typically freeze this time every year with frozen mist and water encasing everything they touch. but they never completely freeze over. there's too much rushing water with 23 million gallons falling every minute during the winter. last month adventurer will gadd took advantage of all that ice climbing 147 feet in about an hour. the only time niagara falls stopped flowing entirely was in march 1848 blocked by an ice jam that allowed people to walk on the riverbed. the landmark area is on track for one of the coldest februarys on record and the ice isn't expected to melt entirely until may. >> it's gorgeous. i think they're even more beautiful frozen than in the summertime. >> reporter: dylan dreyer, nbc news niagara park, ontario, canada. >> spectacular pictures. that's going to do it for us on this thursday night. i'm lester holt.

for all of us at nbc news, thank you for watching and good night. he's a hero for that. >> right now at 6:00 a security guard killed while doing his job. police say there's a break in this case. >> i'm raj mathai. >> an investigation into the shooting death of a security guard who witnesses say took a bullet for a friend. police say they've made arrests in the case. michelle roberts broke the story earlier today. we're in that neighborhood. any shell? >> reporter: the shoot inging

happened here on saturday. there were a lot of people around. police say they are still interviewing witnesses who were here when it happened but they do say they have enough evidence to arrest two people and more could be coming. 36-year-old father and security guard manny zuniga was shot and killed on saturday night. today san jose poelice confirm for nbc bay area that two men have been arrested for his murder. >> the homicide detectives are still actively working this case. and still have a lot of work to do. >> reporter: police spokesperson heather randall says the suspects' names aren't being released. investigators aren't saying if the men in custody are seen in this surveillance video. it shows several men walking into the liquor for less in east san jose saturday night. moments after they walk out one person returns and grabs a cigar display case. he falls on his way out. investigators say that's when zuniga, the security guard began