The return of “The Tonight Show” to Los Angeles — its former home for more than 40 years — has produced sizable ratings gains for NBC this week.

Through three nights of its special telecasts from Universal Studios, “The Tonight Show Starring Jimmy Fallon” was averaging a 1.4 rating/7 share in adults 18-49, according to the 25 markets with Nielsen Local People Meters — its highest-rated Monday-through-Wednesday since last March (Fallon’s fourth week hosting show show).

Its performance was good enough to beat the combined averages of ABC’s “Jimmy Kimmel Live” (0.6/3) and CBS’ “Late Late Show with David Letterman” (0.4/2) in the same 11:35 p.m. timeslot.

And in metered-market households, “Tonight Show” (3.3 rating/9 share) finished comfortably ahead of both “Late Show” (2.4/6) and “Kimmel” (2.1/5).

Compared to its Monday-to-Wednesday quarter-to-date average “Tonight Show” was up a big 40% in adults 18-49 (1.4 vs. 1.0) and 27% in households (3.3 vs. 2.6).

Wednesday’s show, which included visits from Vin Diesel and Kobe Bryant as well as a special “Saved by the Bell” reunion skit, delivered the top “Tonight Show’s” top 18-49 average in the LPMs (1.5/7) since late February (Fallon’s second week as host).

Fallon, who regularly hosts “Tonight” from Rockefeller Center in New York City, has consistently won its timeslot since taking over for Jay Leno nearly a year ago. Last week, even though it aired five encore telecasts, “Tonight Show” averaged a winning 0.80 national rating in adults 18-49, ahead of “Kimmel” (0.68 for his four originals and one repeat) and “Late Show” (0.49 for an all-original frame).

A special post-Super Bowl episode of “Tonight” on Sunday from Arizona averaged 9.8 million viewers despite its late 12:13 a.m. ET start time.