The article suggests the 105 mm howitzer that CDOT is using to clear snow from avalanche-prone areas is an M101, most of which were built in the 1940s.
http://www.theepochtimes.com/n3/1960087-colorado-department-of-transportation-using-world-war-ii-howitzer-to-clear-snow/ (http://www.theepochtimes.com/n3/1960087-colorado-department-of-transportation-using-world-war-ii-howitzer-to-clear-snow/)