Breaking news of an impending storm due to hit on Nov. 27, the day of Thanksgiving, may leave travelers feeling a little anxious. Thanksgiving is one of the biggest travel days of the year, and this storm might throw a wrench in some of those plans.

If your Thanksgiving travel plans take you through the East coast, you might have to plan to leave earlier if possible to avoid some of the weather, or else reschedule your Thanksgiving dinner. Some routes forecast to be affected by the storm include the section of I-35 between the Twin Cities and Des Moines; I-94 through Wisconsin; I-5 from Seattle to Portland; and the section of I-90 that passes through the Rockies. On Nov. 26, Wednesday night, high snowfall could be expected near I-95.

The National Weather Service released a winter storm warning in an area affecting 20 million people. There may be high snowfalls in the storm's path.

Weather forecasters are still unsure how much snow will fall, and how long it will stay on the ground. The storm itself isn't particularly cold, which means that depending on how much snow falls in a particular area, the storm's effect could be limited to a few flakes that melt quickly, or high depths of snow. This outcome will depend on whether snowfall is great enough to bring down air temperatures -- enough to prevent the snow from melting.

The good news is that some major airlines are waiving fees to change departure dates for flights that have already been booked. Meteorologists suggest you leave earlier if you can. In conditions of low visibility, airports much restrict travel to half of normal capacity over Wednesday, causing major delays for folks leaving or arriving in the northeast. The earlier you leave, the likelier you are to miss the effects of the storm and get safely to your Thanksgiving destination.

Drivers should also consider traveling today if possible. Highways in the storm's path might be overwhelmed with snow if there is heavy and rapid accumulation.