They also had snow up to knicker levels in Feb 1894, 45" for three days after Valentine's Day. Started the month with 23" OTG and packed on another 24.9" to reach 45". Records do look a little sketchy at that time, just add new snow to current snow depth to get new snow depth.
There's also Feb 1983 that hit 40 and 41" within a couple days of each other late in the month.
But 1970 looks like the first modern era 40" snow depth.