At least six airports across Florida have stopped flying and are fully closed until Hurricane Milton passes. Orlando International Airport officially closed on Wednesday morning and has canceled more than 800 flights on Wednesday alone. They say they will reopen once it’s safe to do so.

Hurricane Milton is expected to be one of the most devastating hurricanes in west-central Florida and has already significantly impacted air transport in the region. According to the aviation analytics firm Cirium, over 2,300 departing and arriving flights at various Florida airports had been canceled by 7 am Florida time on October 9.

Milton fluctuated between categories 4 and 5 as it approached, and forecasters are warning it will be a major and extremely dangerous storm when its center makes landfall.