A major winter storm is snarling flights in Chicago and elsewhere in the Midwest Thursday, a disruption that comes at the beginning of the busy Christmas travel rush.
Southwest, the nation's largest low-cost carrier, says it is canceling the "majority of our Thursday afternoon and evening flights" from both the Chicago Midway and Milwaukee airports. The airline also says it has canceled "many" of its morning and afternoon flights today to and from Kansas City.
Southwest is the top carrier at Chicago Midway and has a major presence at Milwaukee, where it also is the top carrier if flights at subsidiary AirTran are included. Southwest's cancellations will have a significant impact on flight schedules at both airports.
Southwest, like most other big airlines, has instituted a flexible rebooking policy that allows most customers flying into the storm's path to make one change free of charge.
But, for those who are sticking to plans to fly today, the Midwest is a trouble spot.
Flights bound for Chicago O'Hare - the USA's second-busiest airport - are facing delays of up two hours because of strong winds ahead of the storm, according to the Federal Aviation Administration's flight delay map.
The Chicago Department of Aviation says airlines have axed about 150 flights at the airport so far today because of "low visibility" and wind. That number seems certain to grow throughout the day. As of 11 a.m. CT, delays on departing flights are subject to delays of 30 to 45 minutes, though that number was increasing.
O'Hare is a major hub for both United and American, meaning this morning's disruption could ripple out and affect fliers at other airports.
Chicago's Midway Airport - a major base for Southwest - was suffering more sporadic delays and cancellations as of noon ET ET. About 30 flights have been canceled there so far according to the Chicago Department of Aviation, which adds delays at that airport have generally been "minor."
The problems come from a blizzard that's strengthening as it moves into the Midwest, and conditions are expected to deteriorate for air travelers today across much of the Midwest. That includes Chicago, where heavy rain is expected to switch to ice and snow sometime around 6 p.m. local time.
Already, the storm has snarled flights at several mid-sized Midwest airports. At Des Moines, for example, the airport's online flight information page shows that all but two of this morning's departures there have been canceled. At Omaha, more than a dozen of the airport's morning departures had been canceled as of 7 a.m. local time, according to FlightStats. However, the weather began to improve in both cities by late morning.
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Elsewhere, a number of other airports - including those in Cedar Rapids (Iowa), Green Bay (Wis.), Madison (Wis.) - have reported at least a handful of cancellations so far this morning.
Unfortunately for fliers, the storm is expected to bring worsening blizzard conditions to much of the region today.
Flight schedules at Milwaukee's busy General Mitchell Airport have generally held up well through the morning, but the airport's website shows at least a dozen cancellations now on the board for this afternoon and evening.
The storm is even bringing problems to the South, where a long line of thunderstorms ahead of the storm could block flight paths in that region.
Hour-long delays at Memphis - a hub for Delta - had been reported earlier this morning by flight-tracking service FlightAware, though those problems appear to be easing. Current arrival delays there were averaging 36 minutes as of 10:50 a.m. local time, according to FlightAware.
In Atlanta, travelers flying through the world's busiest airport should pay attention to those storms as they develop.
The greatest risk from those storms is expected to come early to mid-day Thursday. However, the delay threat depends on whether the storms remain in a north-south "line" long and solid enough to block flight paths west of Atlanta.
Unfortunately for holiday fliers, the winter storm could extend its role as Grinch into the weekend.
Detroit, one of Delta's busiest hubs, is expected to see rainy, windy conditions today. The precipitation is forecast to switch to snow, though accumulations are expected to be minimal. Detroit's airport typically handles winter weather well, but given the disruptions elsewhere travelers flying to, from or through the city should monitor conditions and check ahead on the status of their flights.
Similar advice applies to fliers passing through Cleveland, a busy hub for United, which faces a similar forecast for Friday.
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With the edge of the storm forecast to move into the Northeast by Friday, the main concern for air travelers will turn to New York. Snow is not yet in the forecast there, but the predicted gusty winds, clouds and occasional rain are a bad mix for the metro area's delay-prone LaGuardia, JFK and Newark airports. Forecast winds also would bring the risk of sporadic delays at those airports on Saturday.
Even ahead of the storm's arrival, Newark and JFK flights were hit with delays by up to two hours on Wednesday as moderate winds buffeted the airports. Such delays could crop up all over again as the storm moves into the Northeast.
Winds also could disrupt flights Friday and Saturday in Philadelphia, though any problems that develop there are likely to be more sporadic.
As always, customers flying over the busy Christmas holiday travel period should check ahead on the status of their flight, and keep in mind that fair skies at their destination don't mean that they're immune from weather delays. For example, a flight from Charlotte to Dallas could become delayed or canceled if the aircraft or crews scheduled to operate the flight gets stuck in snowy Wisconsin.