Basically, I want to know for a fact that I am in Skyrim, the northern region of Tamriel. And to support this, I think Skyrim's seasons should be similar to that of the Arctic region on our planet, where Winter is actually about 5 1/2 months long, spring 2 weeks long, summer 5 1/2 months long, and autumn being 2 weeks long (due to Earth's axis.) I also want dynamic weather effects where the seasonal effects are instensified based on how North/South you are in Skyrim, for example if you are in Northern Skyrim during winter, there are frequent blizzards. Unlike the way we experience seasons (3 months a season) I think a Skyrim winter should last 1 month in game time, spring lasts a couple of days in game time, summer lasts a month " ". Autumn lasts a couple of days " " (Make sure to include the fact that about a second irl is a minute in TES games). I think seasons should last this long because not everybody keeps playing their character for more than 2 or so months in TES time, so everybody can experience a whole year in a decent amount of time. The reason to why I think spring and fall should be so short is that they are basically the transition time between winter and summer.
Another thing I think should be implemented into Skyrim is season-player effects such as:
Winter: (These effects will only apply if you are caught in a blizzard or if you are out at night) you move slower, attack slower, and slowly drain health based on how insulated your clothes/armor is (insulation could be a new feature to clothing/armor.)
Spring: Nothing happens
Summer: You get fatigued faster based on how insulated your clothes/armor is
Autumn: Nothing happens
Some basic weather effects that I also want to see:
Rain and snow that falls dynamically
Trees lose leaves during fall
Trees grow leaves back during spring
During winter the ground is covered in snow, which leaves tracks when animals/NPCs walk through it.
During fall the ground is covered in leaves which crunch when something walks through them.
Obviously, NPC actions should be based on the season/current weather (children don't play outside during Blizzards)
Buildings should grow icicles during winter.
Rivers freeze in winter
Rivers become rapids during Spring
Your line of sight should be dramatically shortened during winter