Prime-time news shows devoted to Hurricane Katrina's devastating effects on the Gulf Coast drew some of the biggest audiences in last week's Nielsen ratings race.

Four of the top 10 programs were either newsmagazines or specials about the aftermath of the storm, including NBC's "Dateline," which drew more than 12 million viewers to become the most-watched show of the week. Also last Wednesday night, a "48 Hours" special at 8 and an ABC News special at 10 won their time slots with 8.3 million and 9.3 million viewers, respectively.

A second "Dateline" on Friday was also the most-watched Friday night show on any network this summer.

In addition, the broadcast networks' evening newscasts saw a big jump in their numbers during the pre-Labor Day week when ratings are normally low. "NBC Nightly News" was tops with 10.6 million viewers, a 31 percent increase from the previous week. "ABC World News Tonight" averaged 9.5 million (up 21 percent from the week ending Aug. 26) and "CBS Evening News" garnered 7.7 million (up 20 percent).

An estimated 7.4 million people tuned in to NBC's Friday telecast of the "Concert for Hurricane Relief," which raised nearly $40 million, according to the Red Cross. Since the telethon did not have any advertising, it is not officially rated by Nielsen. Another 1 million people watched the concert on CNBC and MSNBC.

For the week, CBS captured its 14th straight victory. It won every week this summer thanks to viewers' continued devotion to its repeats.

Nonetheless, Fox got a boost with the two-hour debut of its drama "Prison Break" last Monday. The series, about a man who breaks into prison so he can break his brother out, grabbed 10.5 million viewers in its premiere, making it the sixth most-watched program of the week. It gave Fox its highest-rated summer Monday night in seven years, when "Melrose Place" and "Ally McBeal" were still on the air. In addition, "Prison Break" was the top-rated show in the advertiser-coveted 18-to-49 demographic.

On Monday this week, the "Prison Break" audience dropped to 8.5 million, although Fox was quick to point out it aired on Labor Day when viewing levels are traditionally down.

The top 10 programs, in order, were: NBC's Wednesday "Dateline"; CBS's "CSI: Miami," "60 Minutes" and "Two and a Half Men" at 9:30; NBC's Friday "Dateline"; Fox's "Prison Break"; CBS's "Two and Half Men" at 9 and "NCIS"; ABC's Wednesday night hurricane special; and NBC's "Law & Order."