Good Morning! temp range the first week is scary RANGE 80-100 have you candled these eggs since? @BG2heum Everyones comments are pretty spot on, do you understand that you are trying to achieve a goal weight loss in the egg, so you have to watch the air cell or weigh eggs from the start to keep track of this loss. Humidity is not a set number as said, its all about what that egg needs to achieve correct weight loss in the majority of your eggs. Hatching Eggs 101 - BackYard Chickens Community Does your incubator have a fan in it? With a Forced Air Incubator (fan model) you can get the best hatch rate by keeping the temperature at 99.5º F. throughout the entire incubation period. HOWEVER, when using a Still Air incubator (no fan) at 102º F. The reason for different temperatures is that with a fan model the circulating air warms all around the egg while still air temperatures are warmer at the top of the egg than at the bottom. The temperature is measured at the level where the embryos develop (at the top of the egg). A high temperature tends to produce early hatches. A consistently cooler temperature tends to increase incubation times and produce weakened chicks. In both cases the total chicks hatched will be reduced. Prepare your incubator and run it for several days before adding eggs, to be positive you are maintaining correct incubation temperature.