Weather By Day

September Weather In Helena  
September Helena Weather
Record High: 99°F
Normal High: 71°F
Normal Low: 41°F
Record Low: 6°F
Avg Monthly Rain: 1.05"
Rec 1 Day Rain: 1.63"
Avg Monthly Snow: 1.5"
Rec 1 Day Snow: 13.1"

Helena Weather In September

In the last 70 years the highest measured September temperature in Helena was 99 degrees Fahrenheit, most recently registered on September 28, 1967, while the typical high temperature is 71. The coldest September day in Helena for the past 70 years was 6 registered on September 23, 1926, while the regular low temperature for a given day during the month is 41.

United States National Weather Service historical Helena September Weather data shows that on September 24, 1934, the high temperature did not exceed 23 degrees Fahrenheit, the lowest high measured in Helena in the past 70 years. The Weather Service additionally indicates that on September 1, 1991, the low for the day did not drop below 64 degrees, the highest low recorded in Helena in the last 70 years.

Historical weather data accumulated by the National Weather Service shows that the average daily high temperature in Helena on September First is 76 degrees Fahrenheit and the average high on the last day of September is 65 degrees. The average recorded low temperature in Helena on September First is 48 degrees Fahrenheit and the average low on the last day of September is 39 degrees.

Helena normally receives an average of 1.05 inches of rain during September. September Helena Weather records indicated that on September 30, 1893 Helena received 1.63 inches of precipitation, the most rain recorded in a single day in September. Helena receives an average of 1.5 inches of snow in September.On September 18, 1957 Helena received 13.1 inches of precipitation, the highest snowfall recorded in a single day in September.