I think I sprayed the basecoat on when it was too hot since there is powder on the surface.  Actually, there are several coats and the paint looks fine, it is just the powder I worry about.
Can I wipe or wash it off and apply the clearcoat, or do I have to start from scratch?
Thanks,
Neal ??)

Sand off the imperfections and then apply a final coat of basecoat (do
not sand the final coat). Make sure the basecoat has dried thoroughly and
then spray the clearcoat.

Please see: https://www.paintscratch.com/touch-up-paint-directions/spraycan.htm