No need to carry so much stuff just to survive.
Just work on your skills and carry less, IE grab the SAS manual and go camping with a friend in mild weather with nothing and work your way up.
Basically everything you see on any survival TV show or youtube is covered in the SAS survival manual.
Also since you are hiking alone always leave an itinerary couple of people.
My last full on mild weather survival pack weighed about
5# with everything including bag, pad, shelter, cooking, survival, medical. It was actually more of a very minimalist SUL hiking kit.
For survival you can always put down some tree boughs for ground insulation if you are below the tree line, but in the 5# pack above I carried one of these in XS which weighs 8 oz. They roll up very small. Better than nothing.
http://cascadedesigns.com/therm-a-rest/mattresses/fast-and-light/prolite/product
You need a small survival kit with all the normal stuff, whistle, mirror, light, matches etc etc. Youtube
has a lot of survival kit videos.
The Adventure Medical Pocket Survival Pak has most of the small stuff you need.
You need a small medical disaster kit.
Quick clot, superglue, a needle and thread, a couple of pads and some duct tape is about as simple as it gets.
The main 1st enemy is exposure and you can get hypothermia if wet in 50DF weather which is not very cold. Just think of a situation where all you gear gets wet in near freezing temps, which has happened to me. Cloths sleeping bag and all and how you recover from that.
So 1st order is to get dry and or stay dry depending on what happens. If you dont have a 2nd change of dry cloths it is imperative that you build a fire to dry your clothing and gear out. That is one time a synthetic bag makes more sense.
I carry quite a few ways to start a fire. A lighter in my pocket, one in the pack, a fire steel in my pocket, water proof matches, a tiny lens out of a camera lens, and a med aventure sparker. I also carry several types of tinder to catch a spark and some heavy duty fire starter. I bought these giant matches from Publix a while back. They are about 1.5" wide and about 4" long and go up in a good hot flame. They are made for grills. Good stuff. Many more fire starter methods like cotton balls soaked in vasoline, but thats the one I like
IMO a good solid knife and a folding or collapsable saw is a must like a gerber or kershaw. I like my Gerber saw so much I use it around the house for trimming trees and shrubs.
If you are stuck and you have time and material you can survive in a debris shelter overnight. If I remember right Cody Lundin lived in a wikiup for a few years while in college. You dont really have to have tools to build one, but a knife, saw, paracord, and a couple of plastic garbage bags and a sheet of plastic makes it a lot easier.
If below freezing and there is enough snow is around, you can build a snowcave and with just a candle will stay just at freezing, but you need a shovel. A couple of 9 hour candles is not a bad thing to have. Also something to boil water in, but I would assume for a day hike you will have some sort of decent size metal cup.
The dual survival show in Nova Scotia where Cody Lundin builds what he called a "super shelter" is when I started carrying a piece of sheet plastic besides a space blanket. Find some natural debris to form the back, space blanket on the back as a reflector, clear plastic on the front to trap the heat and build a fire in front of it. I tried out a makeshift rig about a month ago and its pretty amazing how warm it gets inside.
The trick is to find the right plastic so that sparks from the fire wont burn through it.
They do make fire retardant clear plastic sheeting, but I have yet to try any out.
I will post a link to my current survival pack list later today.
Where you are you would mostly need to add more cloths and a bit more gear.