What we're watching: March Madness is here, the Sweet Sixteen is on CBS tonight and your favorite team should always be in HD. An Inconvenient Truth is also on Showtime tonight, but we can always wait until the day after tomorrow to learn about global warming.

Our traditional high definition listings continue below.



All times are Eastern and reruns are in italics, finales in bold:

ABC (720p)
: Ugly Betty (8 p.m.), Grey's Anatomy (9 p.m.), October Road (10 p.m.)

CBS (1080i): NCAA Basketball Championship Regional Semifinal (7 p.m.)

NBC (1080i)
: My Name is Earl (8 p.m.), Andy Barker P.I. (9:31 p.m.), Raines (10 p.m.), The Tonight Show with Jay Leno (11:34 p.m.)

Fox (720p): N/A

CW (1080i): Smallville (8 p.m.), Supernatural (9 p.m.)

MYNTV (1080i): N/A

Discovery-HD (1080i): Wild Asia (7 p.m.), Austin Stevens: Snakemaster (8 & 11 p.m.), Profiles of Nature (9 p.m.), Bugs!: A Rainforest Adventure (10 p.m.)

TNT-HD (1080i): Law & Order (6, 7, 8, 9, 10 & 11 p.m.)

ESPN-HD (720p): SportsCenter (11 p.m.)

ESPN2-HD (720p): NASCAR Now (6:30 p.m.)

INHD (1080i): London Live (7 & 7:30 p.m.), NBA TV: Nuggets at Bulls (8 p.m.)

Universal HD (1080i): Law & Order: SVU (7 p.m.), Daylight (8 p.m.), Stargate Atlantis (10 p.m.), Firefly (11 p.m.)

HDNet (1080i): Get Out! (7 p.m.), NHL on HDNet: Blue Jackets at Red Wings (7:30 p.m.), NASCAR Nextel Cup Replay (10:05 p.m.)

HDNet Movies (1080i): The Man with Two Brains (6:45 p.m.), Blade Runner (Director's Cut) (8:15 p.m.), Johnny Mnemonic (10:15 p.m.)

HBO-HD (1080i): Transporter 2 (7 p.m.), Life Support (8:30 p.m.), Big Love (10 p.m.)

MAX-HD (1080i): Twister (6:15 p.m.), Dirty Harry (8:15 p.m.), The Sentinel (10 p.m.)

STZ HD (1080i): Shakespeare in Love (6:50 p.m.), Ultraviolet (9 p.m.), Stay Alive (10:35 p.m.)

Showtime (1080i): The Movie Hero (6:35 p.m.), An Inconvenient Truth (8:05 p.m.),This American Life: Reality Check (10:30 p.m.), The L Word (11 p.m.)