BuddyTV reports that Supernatural and Smallville, two of The CW's anchor shows, will be on hiatus after their February 5 episodes. They will return on March 5.

The reason for the break? February sweeps is normally the time when networks use ratings to set the cost of advertising spots. However, because the deadline for all television signals to switch over from analog to digital was originally set for February 17, the sweeps period got moved off to March. The DTV Delay Act, which pushes the digital transition date off to June 12, goes to a vote in the House on Wednesday.

Whether the transition date moves to June or stays in February, networks have moved their sweeps month and are saving episodes to air at a time when they're sure to get the widest audience. The analog to digital conversion delay was proposed because many households did not yet have the converter box. Once the switch happens, any televisions without digital reception capability will be unable to get any signal at all. The networks are favoring the June date, since it will fall after the TV seasons are over, and there were concerns that the February switch date would hurt already struggling ratings.

Sources:
BuddyTV
Associated Press
Wired