AUSTIN (KXAN) -- The City of Austin said Austin-Travis County EMS responded to 12 cold exposure calls, including two "fatal incidents," since Monday as freezing temperatures appeared throughout Central Texas. The City didn't link those deaths to a specific cause, writing the medical examiner's office will investigate the cause of death. ATCEMS told KXAN that both scenes were outdoors and the fatalities were from presumed hypothermia. The city said long-term exposure to cold weather may lead to hypothermia. KXAN First Warning Weather forecast Austin Mayor Kirk Watson said on X as of 8 a.m. Tuesday, an estimated 550 people have used the City's cold weather shelters. The shelters will be open again Tuesday night through Wednesday. Anyone in need of shelter information can call the hotline at (512) 972-5055. "While cold weather shelters are primarily accessed by people experiencing homelessness, they are available to anyone in need of a warm place to spend the night," Watson said on X. The KXAN First Warning Weather team said some areas of Central Texas received 0.5" of snow Monday night and Tuesday morning. Wednesday may be the coldest day of this week with air temperatures in the upper teens and low 20s. KXAN recently spoke with a doctor at St. David's Medical Center who said uncontrollable shivering, slurred speech, confusion and mumbling may be signs of hypothermia. Call 911 if someone needs immediate medical attention.