TV picks: Letterman tribute, Cobain doc, Netflix's 'Grace and Frankie' and more

*  DAVID LETTERMAN: A LIFE ON TELEVISION. 9:30 tonight, CBS3.

Ray Romano, whose 1995 appearance on CBS' "Late Show with David Letterman" led to "Everybody Loves Raymond," oversees a 90-minute tribute to Letterman, which is probably not long enough, considering he'll have hosted 6,028 late-night episodes over 33 years when he signs off May 20.

*  KURT COBAIN: MONTAGE OF HECK. 9 tonight, HBO.

Kurt Cobain's daughter, Frances Bean Cobain (above), is executive producer of the first authorized documentary about her late father. Written and directed by Brett Morgen ("The Kid Stays in the Picture"), it's an occasionally charming, more often disturbing portrait of the Nirvana artist as a young man too long frozen in memory at age 27.

*  FRONTLINE: OUTBREAK.

10 p.m. Tuesday, WHYY12.

Filmmaker Dan Edge investigates the beginnings of the Ebola epidemic.

* DIG. 10 p.m. Thursday, USA.

If you've followed FBI agent Peter Connelly this far down the religious-conspiracy rabbit hole, you might as well see if he manages to postpone the end of the world in the finale.

*  GRACE AND FRANKIE.

Friday, Netflix.

Co-created by Broomall's Marta Kauffman ("Friends"), the streaming service's new comedy stars Jane Fonda (Grace) and Lily Tomlin (Frankie) as frenemies thrown together when their law-partner husbands (Martin Sheen and Sam Waterston) leave them, in their 70s, to marry each other. Sharp writing - and, let's face it, an amazing cast - results in something funny and moving.