and 21% of nypd now out sick. the city hit hard once again. trevor ault joins us once again right here in new york. and trevor, you re learning more from a new study showing the effectiveness of the johnson & johnson booster shot against omicron? reporter: that s right, whit. the study found that second j&j dose provides strong protection even against omicron and it cuts the risk of hospitalization by 85%. whit? encouraging news there. trevor, thank you. the covid surge combined with extreme weather in parts of the country are crippling the final days of the holiday travel season. more than 1,000 flights canceled again today, with luggage piling up. you see here, seattle s sea-tac airport reporting the most cancellations in the world for the third day in a row. jetblue today announcing they re preemptively canceling more than 1,200 flights over the next few weeks because of an increase of covid sickouts. we move on now to the high stakes call between president biden and russi
people some guidance that they seem likely to actually follow. whit? all right, trevor, thank you. now, to the staggering airline cancellations across the u.s. tonight. hundreds of flights grounded again today with no end in sight to the holiday travel nightmare. seattle s sea-tac airport reporting the most cancellations in the world for the second day in a row. heading into new year s eve, bad weather combined with staffing shortages crippling travel for millions. here s abc s mireya villarreal. reporter: tonight, extreme weather on the move and millions of travelers are, too. in the south, severe thunderstorms taking aim. this possible tornado in southwest georgia. in the west, crews preparing for another round of heavy mountain snow and torrential rain. this is i-80 in placer county, california. traffic backups hindering first responders. authorities urging people to stay off the roads. the menacing weather, combined
and hours of waiting. dozens of covid testing sites in new york and new jersey forced to close because of staffing shortages. and cdc director dr. rochelle walensky defending new guidelines about isolation and quarantine. major airlines in the u.s. canceling flights by the hundreds. seattle s sea-tac airport reporting the most cancellations in the world because of weather and the covid surge. pilots, flight attendants and staff all effected. airlines heading into the new year with some of the busiest travel days still ahead. and tracking severe storms as we come on the air. tornado watches in effect across several states. a reported tornado touching down in georgia. and the new winter weather alerts. heavy mountain snow and torrential rain again taking aim at the west. rob marciano timing it all out. outburst in court. the alleged driver accused of killiing two children and injuring several others struggling with a deputy during