David,

I was raised in that country, and have spent many unexpected nights out without camping equipment there and lots of other places. What you have is a great choice, but I would add a more sturdy version of the heatsheet. I use a Space Sportsmans Blanket. If you are in the timber, pitch the reflective blanket as a lean-to with a fire in front. Use boughs or pine straw as a mattress, covered with the poncho. Wrap up in the liner and enjoy a fair night's sleep in fairly severe temps (at least if you sleep as easily as I do). You may need to tend the fire a few times at night, but a few hours sleep at a time will let you rest well.

Don't expect the lean-to to last if you just string up the blanket. Take some time to make a frame of small wood and, particularly if it is snowing or blowing hard (common in Colorado), cover it with boughs.

Use the other things you carry for help. My ruck has a removable foam backpad. Place it under your hips or shoulders. Remove your boots and replace your socks with the dry ones everyone has recommended. Then use your ruck as a foot cover.

Drink plenty of water (hot is best). Eat some of the spare food so the fire in you can keep going. Fats, proteins and complex carbs feed you longer. Food and drink is particularly important to staying warm.

If you are above timberline, sit on the pad in a protected place (from the wind/snow,rain) put the ruck over your feet, use the poncho, liner and sheet as layers. Pull the liner snug around you. Use the sheet and poncho as a mini tent, not so tight to minimize condensation. Some cannot sleep sitting, but if you can it can be a relatively comfortable night if you brought enough clothes. The Inuit use this technique (although with their large parka as the top and their mittens to sit on) to weather out blizzards. In some really nasty conditions.

Respectfully,

JerryF