Yup. Lois is definitely about to go back in time. The strange colours in the sky are probably a side-effect of a portal.
The only question regarding the dress is whether Lois will buy it in our time or after she journeys back into the past.
It's a good thing Lois has that picture with her; it will probably help her to convince the Clark Kent of the past that she is, in fact, not insane.
Joy,
Lynn
