DENVER (KDVR) — Southwest and Frontier airlines issued travel alerts for passengers flying to and from Denver International Airport and several other Colorado airports ahead of weekend’s winter storm.

In a travel advisory posted on Southwest’s website, it said passengers could experience travel disruptions if they are flying in or out of airports in Denver, Colorado Springs, Steamboat Springs and Montrose Friday through Sunday.

Passengers can rebook in the original class of service or travel standby within 14 days of their original date of travel without paying any additional charge.

Frontier Airlines posted a travel advisory on its website alerting passengers flying in or out of Denver and Colorado Springs on Saturday and Sunday. According to the alert, customers who purchased tickets on or before Monday may make one itinerary change.

Frontier said for those passengers, rules/restrictions regarding standard change fees, advance purchase, day or time applications, blackouts, and minimum or maximum stay requirements will be waived.