The thermometer hit 90 degrees by the time the P-rade kicked off at 2 p.m., and few people were hotter than the P-rade marshals, who hurried strolling marchers along, supervised spectators, and kept order — all while wearing long pants, white dress shirts or blouses, dark blazers, ties or scarves, and puffy velvet orange-and-black hats. More than a few marshals commented — off the record, of course — on how warm it was under all that garb. (University band members, who walked the entire route several times while playing instruments and other devices, might claim to have suffered more ... but they’re younger and hardier.) We asked illustrator Ron Barrett to envision hot-weather options for the marshals.