WB dramas “Gilmore Girls” and “Charmed” could well find a second home on sister cabler TNT as soon as this fall.

The WB and TNT are in talks to carve a dual window for both shows on the cable web within seven days of their initial Frogcast. TNT would broadcast the series at 10 p.m. — which puts the skeins within primetime, but after the WB goes off the air.

The WB could also share rookie skein “Smallville” and vet drama “Felicity” with TNT.

The WB may announce the plan at its fall upfront presentation this morning in New York. The netlet just finalized multiple-year renewals with four top series, including Spelling Television’s “Charmed” (Daily Variety, May 14). Sources said the new “Charmed” pact allows the WB to multiplex the skein elsewhere, such as TNT.

As it stands, TNT is expected to schedule “Gilmore Girls” — which will air Tuesdays at 8 p.m. in the fall on the WB — at 10 p.m. Mondays. “Charmed,” which will remain at 9 on the WB’s Thursday night lineup, would be slated for Tuesdays at 10 p.m. on the cable net.

Since assuming oversight of both outlets earlier this year, Turner Broadcasting CEO Jamie Kellner has made it a priority to share programming between the WB and the Turner nets. The dual window allows the WB the ability to cover a show’s license fee quicker — especially dramas, which don’t repeat well (and as a result sometimes aren’t repeated at all).

Sources said “Gilmore Girls” and “Charmed” were chosen partly because the series are self-contained and not serialized like “Dawson’s Creek.”

The dual “Gilmore Girls” and “Charmed” windows are similar to ABC’s deal with Lifetime to share “Once and Again,” as well as the split run of “Law & Order: Special Victim Unit” on NBC and USA.