That sound you hear is the collective sigh of relief from the programmers for five networks as “American Idol” (7 p.m., Fox) pulls back from two hours to one. As expected, the talent spectacle has set the ratings standard for the young year, crushing everything in its path. Wednesday’s two-hour “Idol” attracted a bigger audience than its rivals CBS, ABC, NBC, CW and MY Network – combined.

Early winter is a good time to attract huge numbers of viewers. Of the top 30 most-watched TV events of all time, all but two aired between November and February. The Super Bowl is a giant exclamation point on this argument. It makes sense. It’s time to hibernate. Even with global warming (still just a crazy theory to some, or at least to Glen Beck), it’s a time when vast parts of the United States are threatened with ice and snow and cold weather.

Fox has been smart to launch many of its series during this time of year. I find it comforting sitting in my darkened winter TV cave watching Jack Bauer start a new day on “24.” I seem to remember watching “Joe Millionaire” beginning in the dead of a very cold winter. In retrospect, maybe it required subzero temperatures to make “Joe Millionaire” seem like must viewing.

¢ Another dividend of the truncated “Idol” schedule is the return of “House” (8 p.m., Fox). The troubled medical wizard returns from a short stint in rehab to treat a rape victim who asks him to unravel a different kind of medical mystery.

¢ MTV offers a new Tuesday-night lineup that can be appreciated only with the volume cranked up all the way. “Road Rules” (8 p.m., MTV) returns featuring six veterans of the series. This season, viewers are invited to log onto www.roadrules.mtv.com and vote to determine what two players enter an elimination round. And there’s another catch: The fateful round can be seen only on MTV.com.

“Bam’s Unholy Union” (8:30 p.m.) documents the lives of skateboard pros as well as “Jackass” star Bam Margera and his fiancee, Missy, as they plan their wedding.

The documentary series “Two-a-Days” (9 p.m.) returns for a new season. “Two” follows the true-life drama of a small-town Alabama football team with a tradition of gridiron excellence.

“Wrestling Society X” (9:30 p.m.) profiles some of the best and most unique practitioners of the spectacle in front of hundreds of enthusiastic fans.

Tonight’s other highlights

¢ Scheduled on “Dateline” (7 p.m., NBC): predators in Long Beach, Calif.

¢ Sookie sulks and Luke fights for custody of April on “Gilmore Girls” (7 p.m., CW).

¢ A dangerous “package” proves elusive on “The Unit” (8 p.m., CBS).

¢ Liza Minnelli guest stars on “Law & Order: Criminal Intent” (8 p.m., NBC).

¢ “Frontline/World” (8 p.m., PBS) looks at a domestic terror cell.

¢ A violent predator returns for a second assault on “Law & Order: Special Victims Unit” (9 p.m., NBC).

¢ Denny takes on animal-rights zealots on “Boston Legal” (9 p.m., ABC).