Measuring Snow melt in rain guage.

[Delta76]

Hi , can anyone help

Last night i measured 13.5mm of rain in my gauge the trouble is there was a thick snowfall giving approx 1.5 inches on the ground . does anyone know how to equate snow into rainfall as i'm pretty sure the 13.5mm measurement is way over the amount for my area last night .

[Cookie]

its still rainfall just frozen?