Drooping fan leaves

Here's the setup:
4 female AK-48 plants from Nirvana
400W HPS w/ vented reflector
FoxFarm Ocean Forest Soil
Full complement of FoxFarm nutes/additives (as per FF feeding schedule)
Superthrive with every watering
5'W x 2'D x 6'H room
Mylar on three walls
Temps are about 68 F at night and 83 F during the day
Humidity between 40-50%


I came home today to find all of the fan leaves on all four of my plants hanging almost straight down. The leaf stems felt very limp and weak. The plants are in their third week of flower and have lived stress-free lives up to this point. Two things were different today than other days. I forgot to crack open my window before leaving for the day, and room temps climbed to 93 degrees F. The soil also got a bit dry as I did not water last night, but that is not that unusual as I typically water every other day and never overwater.

Any thoughts/suggestions? I suspect it was underwatering as my mother plant reacted similarly about a week ago when I let the soil get too dry. But I really want to know for sure as these ladies have lived a life of luxury and I want to keep it that way!

Thanks in advance for any input all!

first, i'd say water, then heat

it seems to show both probs in the pix, the limp stems and downward angle indicate they are thirsty, the upside down canoe look is from heat stress

exactly. the heat would have caused the plants to use up the water faster too, so that's why they drooped when on normal days they wouldn't have. poor babies! (they will be just fine tho, don't worry)