The record-shattering cold gripping most of the United States has been blamed for at least nine deaths in recent weeks and forecasters say the worst is yet to come.

The National Weather Service issued wind chill advisories and freeze warnings Tuesday for 40 U.S. states.

"Arctic air mass will bring a prolonged period of much-below-normal temperatures and dangerously cold wind chills to the central and eastern U.S. over the next week,” NWS tweeted.

Hard freeze warnings remain in effect through Wednesday in typically balmy states, including Texas, Louisiana, Mississippi and Alabama. Temperatures fell to -13 Celsius (8.6 Fahrenheit) near Cullman, Alabama, and -7 Celsius (19.4 Fahrenheit) in Mobile, Alabama.

City officials opened warming shelters across the South as cold temperatures brought rare snow flurries as far south as Austin, Texas. In Savannah, Georgia, where the average high temperature in January is 16 Celsius (61 Fahrenheit), the temperature hovered at -1 Celsius (30.2 Fahrenheit) at noon Tuesday.

Hospitals across the U.S. are seeing a surge in emergency room visits for hypothermia and other ailments as temperatures plunge well below freezing.

The central U.S. has borne the brunt of the frigid temperatures since the snap began around Christmas. Omaha, Nebraska, broke a record dating back more than 130 years as teeth chattered in temperatures of -29C (-20 Fahrenheit). While Aberdeen, South Dakota, saw the mercury fall to -36C (32.8 Fahrenheit), breaking a record set in 1919.

Arctic temperatures also caused problems on waterways, for both waterfowl and boats. Firefighters in Richmond, Virginia, freed a swan that was stuck for hours Monday in the middle of a frozen pond.

In New York, transportation officials suspended the Newburgh-Beacon commuter ferry service on Tuesday because of icy conditions on the Hudson River. In Florida, several water parks in Orlando are closed because of the extreme temperatures, CNN reported.

Tourists visiting the Horseshoe Falls at Niagara Falls snapped photos of flowing water that had turned to icicles.

The Atlantic White Shark Conservancy reported frozen sharks were washing on beaches south of Boston

The sun reflects off of snow and ice on a farmer's The sun reflects off of snow and ice on a farmer's frozen field in Ronks, Pennsylvania, Jan. 2, 2018. The sun reflects off of snow and ice on a farmer's frozen field in Ronks, Pennsylvania, Jan. 2, 2018.

Meanwhile, forecasters are tracking a storm that could bring snow and ice to the East Coast later this week. The private AccuWeather forecaster said the cold snap could combine with a storm brewing off the Bahamas to bring snow and high winds to much of the Eastern Seaboard as it heads north on Wednesday and Thursday.