Excessive Boil Off

[brewyourown4life]

just wondering if anyone has experienced this. brewed outside a month ago the air temp was about 20 degrees, boiled like i always do but instead of boiling off my typical 1.25 gallons in 60 min i lost 3 gallons! had to top off with 2.5 gallons. typically start the boil with 6.5 -7.5 gallons depending on what i'm brewing.

 

[osagedr]

Yeah, humidity can make a big difference. It's also not that difficult to accidentally boil a lot harder than you intended. Between the two I can see how you could lose double what you predicted.