Update: Some offers mentioned below are no longer available. View the current offers here.A blizzard is ripping its way through the central US, leaving thousands of flight cancellations in its wake. And it’s likely to get worse. Weather forecasters are predicting that the winter storm – dubbed Ulmer by The Weather Channel – will become a bomb cyclone and dump more than 18 inches of snow in parts of the Midwest. Seven states are already under a Blizzard Warning due to the storm.Here’s what a “Bomb Cyclone” Actually MeansTop sustained winds of up to 50 mph are expected with High Wind Warnings currently outstanding for seven states. This level of wind is likely to lead to numerous flight cancellations. So far Monday through Friday, there have been nearly 2,300 flight cancellations in the US, with 1,464 on Wednesday through 12:00pm ET. The airports hardest hit by flight cancellations so far this week are:Denver (DEN): 1,185 cancellations – including 1,083 so far WednesdayDallas/Fort Worth (DFW): 338 cancellations – including 153 so far WednesdayChicago O’Hare (ORD): 140 cancellations – including 65 so far WednesdayPhoenix (PHX): 86 cancellations – including 54 so far WednesdayAspen (ASE): 51 cancellations – including 37 so far WednesdaySalt Lake City (SLC): 50 cancellations – including 40 so far WednesdayTo help travelers affected by the storm, airlines have issued weather waivers. Travelers with plans to fly during the storm may be able to change their flights to an earlier/later date or route through another airport that isn’t expected to be affected by the storm.Through 12:00pm ET Wednesday, seven airlines have issued weather waivers so far covering 30 airports.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.Here’s what’s been issued so far:American AirlinesTravel date: March 13Airports covered: Aspen, Colorado (ASE); Bismarck, North Dakota (BIS); Colorado Springs, Colorado (COS); Denver, Colorado (DEN); Durango, Colorado (DUR); Fargo, North Dakota (FAR); Grand Junction, Colorado (GJT); Gunnison / Crested Butte, Colorado (GUC); Jackson Hole, Wyoming (JAC); Montrose / Telluride, Colorado (MTJ); Rapid City, South Dakota (RAP); Sioux Falls, South Dakota (FSD); Steamboat Springs / Hayden, Colorado (HDN); Vail / Eagle, Colorado (EGE)Must have purchased your ticket by March 12Rebook travel anytime between March 12-17You can’t change your origin or destination city. Must rebook in same cabin or pay the difference.Avoid the phone queue. Changes available on both AA’s website and in the AA app.DeltaTravel dates: March 13-14Airports covered: Aberdeen, SD (ABR); Aspen, CO (ASE); Bemidji, MN (BJI); Bismarck, ND (BIS); Brainerd, MN (BRD); Casper, WY (CPR); Colorado Springs, CO (COS); Denver, CO (DEN); Duluth, MN (DLH); Fargo, ND (FAR); Grand Forks, ND (GFK); Grand Junction, CO (GJT); Hayden, CO (HDN); Hibbing, MN (HIB); International Falls, MN (INL); Montrose, CO (MTJ); Rapid City, SD (RAP); Vail, CO (EGE)Tickets must be reissued on or before: March 17Rebooked travel must begin no later than: March 17Must have purchased your ticket by March 12Changes to origins and destinations may result in an increase in fare. Any difference in fare between your original ticket and the new ticket will be collected at the time of booking.FrontierTravel dates: March 13-14Airports covered: Colorado Springs, CO (COS) and Denver, CO (DEN)Must have purchased ticket by March 12Rebooked travel must be completed no later than: March 29Customers may make one itinerary change – rules/restrictions regarding standard change fees, advance purchase, day or time applications, blackouts, and minimum or maximum stay requirements will be waived.JetBlueTravel dates: March 13Airports covered: Denver, CO (DEN) and Steamboat Springs, CO (HDN)Customers may rebook their flights for travel through March 16Original travel must have been booked on or before March 12SpiritTravel dates: March 13-14Airports covered: Denver, CO (DEN)Modification Charge/Fare Difference waived through: March 16After this date, the modification charge is waived, but a fare difference may apply.Guests can make changes to their reservations affected by this event by going to our Manage Travel page, or by calling the Spirit Reservations Center at 801-401-2222 to make their flight changes. To make changes to Spirit Vacation packages contact Spirit Vacations at 954-379-8866.SouthwestTravel dates: March 13-14Airports covered: Chicago (Midway), IL (MDW); Denver, CO (DEN); Des Moines, IA (DSM); Kansas City, MO (MCI); Milwaukee, WI (MKE); Minneapolis/St. Paul, MN (MSP); Omaha, NE (OMA); Salt Lake City, UT (SLC); Wichita, KS (ICT)Customers who are holding reservations to/from/through the cities above on the corresponding dates may rebook in the original class of service or travel standby (within 14 days of their original date of travel between the original city-pairs and in accordance with [Southwest’s] accommodation procedures) without paying any additional charge.UnitedTravel dates: March 13-14Airports covered: Aspen, CO (ASE); Bismarck, ND (BIS); Casper, WY (CPR); Colorado Springs, CO (COS); Denver, CO (DEN); Devils Lake, ND (DVL); Dickinson, ND (DIK); Duluth, MN (DLH); Durango, CO (DRO); Fargo, ND (FAR); Gillette, WY (GCC); Grand Junction, CO (GJT); Gunnison, CO (GUC); Hayden, CO (HDN); Jamestown, ND (JMS); Laramie, WY (LAR); Minot, ND (MOT); Montrose/Telluride, CO (MTJ); North Platte, NE (LBF); Pierre, SD (PIR); Pueblo, CO (PUB); Rapid City, SD (RAP); Scottsbluff, NE (BFF); Sioux Falls, SD (FSD); Watertown, SD (ATY); Williston, ND (ISN); Vail/Eagle, CO (EGE)The change fee and any difference in fare will be waived for new United flights departing on or before March 17, as long as travel is rescheduled in the originally ticketed cabin (any fare class) and between the same cities as originally ticketed.​​No waivers (yet) from: Alaska, AllegiantProtect Your TravelsThis winter storm is another reminder to book flights with a card that offers solid trip delay and cancellation insurance. Cards with solid trip protection include the Chase Sapphire Reserve and Chase Sapphire Preferred Card.