I recently used the Dicor Lap Sealant to replace a mushroom vent. It was on a sunny day but probably only in the mid 60s.
You can see after the damaged vent was removed the original sealant had wrinkled the roof fabric around the vent.
I used a new tube of the Dicor Lap Sealant and it applied in globs around the new vent base but within minutes had settled to a nice round evenly thick seal. I wasn't concerned with what looks to be in the photo a few small bubbles???
Mike & Helen
2014 Voltage 3895 EPIC III
2013 Ford F350 CC DRW FX4