I live in the colder part of the world, which you can probaly tell by my choice in clothes. Wind and rain are always a possibility when i hike and even in summer it gets chilly during the night.
My pants are a brand called Haglofs. Theyre reinforced at the seat, knees and ankles. Cargo pockets are a must for hiking. Theyre synthetic, light, windproof and extremely quick drying.
Always pack a hardshell with me. I like The North Face. Pit-zips are a must, as is "Napleon pockets" so theyre accesible while wearing a hipbelt. My current one is made in PAcLite Gore-Tex which is lighter than the regular. Also have a heavy duty Mountain Hardwear hardshell for winter hiking. This one has a long cut, so your butt is covered, even while sitting. This one is also reinforced with some cordura-like material at the elbows, shoulders, etc. Its abit overbuilt for regular hiking. I save this one for harsh conditions.
For snowy conditions i use a Mountain Hardwear down jacket. Ive never been cold in that jacket. Its the red one seen in my avatar. I think its called Below Zero. Its got alot of nice details, such as fleece-lined pockets and micro-chamois over the zipper to prevent chafing.
Upperbody wear usually consists of a Helly Hansen baselayer shirt. Its important that it wicks sweat away. Again, its synthetic. Only minus about synthetics, is that youll stink like hell after a days hard hike.
On top of that i usually wear microfleece of some sorts. I find that fleece offers most warmth for the money. I like wool, but find it too expensive.
Here i am wearing my Haglofs pants and microfleece shirt, Millet windstopper softshell vest and a thin North Face beanie. Underneath i had the HH baselayer shirt.That combo kept me warm on a windy overcast hike, where temps were about 48 F. It was probaly colder if you factor in the windchill effect. I took of the vest when i was hiking with the pack. Of course, id be sweating while hiking, but id dry relatively fast.