On a night that all but wrapped up Thursday’s portion of the 2008-09 primetime season, “Grey’s Anatomy” was the dominant force, powering ABC to an easy victory among adults 18-49 along with a narrow edge in total viewers over CBS, according to preliminary nationals from Nielsen. Typically, ABC wins the demo but loses the overall viewer race Thursdays to the Eye.

The two-hour season finale of “Grey’s,” which delivered much-anticipated plot climaxes and then some, drew an 18-49 rating and share of 5.8/16 and total audience of 16.3 million. The demo rating was its highest in three months and its total audience was the best for “Grey’s” since its September season-opener.

Also showing a boost in its season wrapups were Fox’s “Hell’s Kitchen” (3.1/8, 7.4 million) and the CW’s “Supernatural” (1.3/3, 2.9 million). By contrast, the season finales of CBS’ “CSI” (3.4/9, 14.6 million) and NBC’s “The Office” (3.5/9, 6.7 million) and “30 Rock” (2.8/7, 5.7 million) shed a fraction of viewers from the previous week.

The NBC sitcoms were tops at 9 p.m. in key male demos.

At 8 p.m., CBS’ “Survivor” (3.7/12, 12.0 million), which ends its season Sunday, was the easy winner over the season finale of Fox’s “Bones” (2.5/8, 8.7 million). “Ugly Betty” (2.0/6, 6.8 million), which will end its season next week, virtually tied NBC season finales “My Name Is Earl” (2.0/6, 4.8 million) and “Parks and Recreation” (2.0/6, 4.2 million) among viewers 18-49 in the hour.

“Earl,” on the bubble for renewal, showed a bump for what might have been its final episode, while “Parks” held steady compared to the previous week. Also at 8 p.m. was the CW’s “Smallville” (1.4/4, 3.2 million).

At 10 p.m., the season finale of CBS’ “CSI: NY” (3.0/8, 12.8 million) came in second behind “Grey’s,” which picked up steam in its second hour. NBC’s “Southland,” which debuted in early April to a 3.2/9, and nearly 10 million viewers overall, drew 1.7/5, 4.6 million Thursday.

Preliminary 18-49 averages for the night: ABC 4.5/13, CBS 3.4/9, Fox 2.8/8, NBC 2.3/6, Univision 1.4/4, CW 1.3/4.

In total viewers: ABC 13.2 million, CBS 13.1 million, Fox 8.1 million, NBC 5.1 million, Univision 3.6 million, CW 3.0 million.