A major winter storm is taking shape from the Midwest to the mid-Atlantic forthe end of the week. Snow over the Plains is expected to be light, but it willbe enough to cause travel headaches from Oklahoma City to Rapid City to theTwin Cities. However, bigger issues will be found farther south where inches ofrain could fall and in the mid-Atlantic where well over a foot of snow couldfall.What is making this storm such a big hitter? You can trace the origins of thisstorm back to the western coast of Mexico. This monstrous storm has a tropicalconnection of moisture not only from the Pacific Ocean, but from the Gulf ofMexico as well. This means a lot of precipitation over a very large area.

The other ingredient needed is cold. This is found over the Northeast due tothe remnants of a cold Canadian high pressure. Putting the two main ingredientstogether, moisture and cold, you get the basis for yet another winter stormfrom the Midwest to the mid-Atlantic.

Story by AccuWeather.com Meteorologist Adam Douty