Is this mold during veg?

Yes, this is the start of a major fungal attack. Unfortunately survival and recovery are difficult. The lower and most affected leaves will probably wither and die, but as long as the growing tip stays healthy, there is hope. Spraying them with a milk and water mixture may help, but these days when this happens, I will get rid of them due to the slow and extended recovery phase. You can plant new seeds and have them at a comparable size by the time these recover however. Removing the worst affected leaves does not seem to prevent it spreading, it seems as once the spores are present, it is almost impossible to get rid of them. Leaving the plants to battle on through it can work, placing some shade cloth over them can help, as if temps are high, this will stress the damaged leaves quickly, possibly leading to complete plant death. If you cover them with shade cloth, make sure it is like a roof, and make sure the sides are open for proper air flow. The 95 temps and 80% humidity and lots of rain have all combined to cause this and is one of the risk factor we as outdoor growers face each season. Toughing it out after spraying them with one part milk to 10 parts water every couple of days and combined with the shade cloth cover (about 50% grade) might lead to recovery, but starting some back up seedlings asap is what I would be doing, just in case these plants don't pull through. Hope this helps, Organoman.