The change over was very quick. I saw flake size and intensity increasing so I got dressed to go out and enjoy.. As soon as i opened the door I heard the pings. A minute later it was all sleet. Now its pouring sleet. A kick in the nuts.
Neat trivia.... largest snowflake ever recorded is 15" in width, observed in Fort Keough, MT, in 1887. I want those. I bet those were some incredible ratios!
It seems from experience that the mix line always pushes faster and further north than modeled / forecasted. I cannot recall one event where we got less mix than forecasted.