Aircraft were unable to land at Glacier Park International Airport in Kalispell on Wednesday because of thick fog.

The reduced visibility caused numerous flight delays and cancellations that continued into Thursday morning.

Periods of widespread fog were expected to linger through the weekend as a high-pressure system causes inversions in the Flathead Valley. Visibility near the airport was about a quarter-mile on Thursday morning.

Glacier Park International officials cautioned that more delays or cancellations are possible if the fog persists.

Officials advised travelers to contact their airline to check flight status and make alternate plans if necessary. Flight status information is also available on the Glacier Park International Airport website at iflyglacier.com/flights.

High moisture near the ground may also create slick spots on roads for the morning commute, the National Weather Service in Missoula warned.