temperature dropping. >> i have been in afghanistan twice and i think this is the worst. >> duncan: president biden returns to washington, pledging help is on the way. also tonight, covid alert, delta drives new cases across the u.s. while omicron causes alarm overseas. >> i'm elizabeth palmer in seoul, south korea which is struggling with a record surge in covid cases. >> and later, remembering the vincente fernandez, mexico's national treasure and king of-- music. this is the cbs weekend news from new york, with jericka duncan. >> duncan: good evening, we begin tonight with this. scores of people remain unaccounted for tonight with dwindle hope of finding them alive after tornadoes caught a swath of destruction across at least six states. the vicious centerpiece with a