Augustine Island is essentially a lava dome complex that creates an island located in the Cook Inlet, Alaska, in the Kenai Peninsula Borough. It is one of the most active volcanos in  Aleutian Arc. Its most recent eruptions were in 1883,1986, and in 2006, as shown in the picture below. The volcanic ash plume can be seen in almost the very center.

Located just outside the heart of the Aleutian Low at 59.378 N 153.348 W, it is therefore is subject to the almost permanent low pressure systems that circulate in the North Pacific. 

NASA image created by Jesse Allen, Earth Observatory

Photo by Bill McGuire

Shown below is a chart from the AUGA2 Station on Mount Augustine,  taken from the National Data Buoy Center. It shows, in Degrees Celsius, the average and standard deviation of monthly temperatures throughout the year. 

The climate of the Mount Augustine is a maritime climate and is therefore rather wet from the warm air over the Pacific, however stays relatively cool in the summer and can be extremely cold in the winter, as seen above, due the the Aleutian low pressure system.