Just based on the info I've read and seen on FLIR, they can detect very minute variances in heat. Can it be detected? I would think so since you have your lights concentrated in one spot so the thermal image will show that area of higher temps. Will it be detected? I would say in most cases probably not. But then again most cases aren't under the level of scrutiny you are.

Imho, regarless of a heat signature on a FLIR camera or not, you have too many interested eyes looking your direction. If you've been popped twice, they won't need FLIR to pop you the third time.