I know this may be more complicated than it appears , but I have always wished that precipitation be called just Precipitation ( or Precip) and whether it was snow or rain would be determined by the temperature in the .mis file.
In this way IL2 could represent "shoulder season" weather , and we could represent the first snow of the year (when none has accumulated) and a miserable late winter day when the precip is rain , though there is snow on the ground.
Both of these are very common ( though not necessarily desirable in life or for flight sim pilots who must fly in it) weather conditions every year in temperate climates.
Imagine if you will flying a Stalingrad campaign which starts in the sun of Indian summer , and then transitions into forboding snow flurries of November,
or the miserable spring of 1945 in central Hungary when the snow gives way to slushy rain just as the Germans launch Unternehmen Freulingserwachen , and the tanks bog down in the slush and mud.
I always felt disappointed that while the designers took the time to model both forms of precip , they limited the application of them by restricting snow to "Winter" maps , and rain to non-winter maps , when much of the work had already been done to represent broader weather types.
Cheers,
Kopfdorfer