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Montana is a mountainous western state that borders on to the Canadian provinces of Alberta, British Columbia and Saskatchewan. To the east it borders the US states of North & South Dakota, to the south the state of Wyoming and to the west the state of Idaho. Montana is affectionately know as "Big Sky Country". The capital city is Helena, with the largest city being Billings.
The climate of Montana is split in two, with the western side being the milder compared to the east. Montana holds the record for the coldest recorded temperature in the whole of the United States of -70f/-57c measured at Rogers Pass in 1954. As Montana is such a huge state, there are great variations in temperature, but at Grand Falls, the January temperature averages 21f/-6c and in July 69f/21c. Rainfall for the year is about 14 inches.
Scuba diving in Montana takes place mainly in reservoirs and also a point to remember is that all dives are high altitude dives. A popular spot is Big Horn Canyon National Recreation Area, which is 50 mile long reservoir. Another popular site is the Glacier National Park, which has the Pitch Fork Forest. Also, Canyon Ferry near Helena has dive sites where you can do shore diving from various picnic areas and there is also boat diving.