I Get It, But Still Why?

Since at least last Wednesday the weather forecast in Chicago was for wet snow Sunday night into Monday morning. Sure enough, when I got up this morning there was somewhere between 1" and 1.5" on my deck and it was still coming down lightly. On the commute to work NPR announced that there have been 50 flights canceled at O'Hare this morning and delays of up to 45 minutes.

On one level I understand why snow and heavy storms cause problems at O'Hare. During peak hours the airport is operating at maximum capacity. When things have to be slowed down for weather everything gets hosed. But it still doesn't make sense that every little weather event that can't be described as "clear and sunny" causes delays and cancellations. Everyone knew this snow was coming for a week and still they are having these problems.