normally rainey and not t oo cold, ocasionally some snow but someyears it dosent stick and turns to slush and some years it does and you get to have a snow day!!
Low to mid 20s during the day and around 20 at night (Celsius of course). Locals might say to bring a sweater because to them 18 or 20 is COLD, but it might be a good idea just in case.
It really depends on where you live. I can't tell you about where I don't live... someone else maybe can... but I live in the northeast and we normally have cold temps and a little snow at the end....