Cold weather noob needs your help.

Hi Brian,
Literally sounds like paradise where you are. Your list looks pretty good. The one thing I'd include for 20 F temps is a good insulation layer. If rain is uncommon, down would be the lightest way to go (eg. Montbell alpine lite parka). If it will be closer to zero, you might want something even warmer.

A typical cold weather layering system for me would include:
Upper body:
1. baselayer (I like wool)
2. thin nylon windshirt- adds warmth but breathable enough to wear while walking
3. +/- a midweight baselayer or light fleece (eg pata R1) when really cold. Can wear while walking/boating
4. Insulation layer- put on when resting or in camp
5. Raingear- I like a poncho tarp, but any 5 oz rainjacket would be fine. If rain is uncommon, I'd go light and cheap.

Lower body:
For temps in 20s, I just wear boxer briefs and quick drying pants. You might like the long underwear if chilled easily.
Liner gloves,hat, and warm sleep socks complete the list

Hope this helps. I'm jealous of your 13er volcanoes
Ike

For a trip _over_ Mauna Loa, I took no proper shelter with me. Instead, I slept in lava caves. I guess they were lava tubes where one piece had collapsed. Inside, they were each about the size of a compact pickup truck, and that was perfect for me. The trick is that you have to know exactly where to look for them. In both cases, I was just slightly outside the park boundary.

I had no insulated pants, but I did have wind pants to go over my normal trousers.

Yes, there was a tiny bit of snow and frost.

–B.G.–

I've been up Haleakala twice at 10,000+ feet and what impressed me was the wind, so I would prepare for strong wind and wind chill lowering the effective temperature.

Someone mentioned a poncho and, as much as I like them, I wouldn't bother in windy exposed terrain like that. IMHO, the best "what if" rain option is a DriDucks jacket. It will block wind too.

The wool base layer isn't bad, but you might consider a polyester one that would be better to use at home– a silkweight like Capilene 1. Then layer that with a mid-layer like R-1 or Power Stretch, or wool. At 20F I would want a puffy layer– your softshell will provide some wind and water resistance, but it won't provide much insulation. In fact, I would have a windshirt and a puffy layer rather than the softshell. How much puffy depends on your other layers and your comfort. If I had a base layer plus a mid, something like a Micro Puff or down vest would be good, YMMV. The windshirt should have enough room for the layers and avoid compressing the puffy layer. Softshells aren't as good for layering with lofted insulation unless they are light and have lots of room. You could wear a vest on top, but it will work better under an outer shell.

If you aren't used to cold, good gloves, beanie cap, or a buff or balaclava will make things cozy. An extra pair of thick socks will help for camp and sleep. When your extremities are cold, it makes the perception of cold worse I think.

If sharp volcanic rock is a concern, a CCF foam pad might be a better bet, or one in combination with your air pad.

The cabins may have foam mattresses (http://www.travelblog.org/Photos/3576176) and you will be protected from the wind much better than any tent. At any rate you'll be sleeping on wooden bunks and not on the ground. I would be okay in a 20F bag, but if you aren't used to it, a warmer bag makes sense to me– depends on the bag. Perhaps you can rent one— it seems a shame to lay out big bucks for one trip and a couple nights.

Bob's advice on the caves is a gem if you are not able to make it to shelter. Blown dust and pumice may make sleeping outside a shelter a pain and watch your camera too– volcanic dust can jam the lens. I've woken up with windblown sand in my ears and everywhere– nasty.

Have fun, and catch the sunrise— awesome in the true meaning of the word.

Thanks! Great advice.

Especially the wind, I always forget about wind chill. I was in DC last year for that mini blizzard and froze my butt off at Washington Monument because it's so exposed. That was really my only exposure to this sort of weather and I found I really only got cold when I wasn't moving. I guess I have pretty good circulation!

And the dust. Hadn't thought about that either, typical hike here you're more concerned about twisting your ankle on a tree root, rock (stream hikes) or slipping off a ridge to your death due to our crumbly and slippery rock hehe :) great advice on that. Won't be hauling a dslr. Either a gopro or my TS2 (maybe both)

Based on your feedback think I'm going to go with a long sleeve synthetic next to skin like an Asics Thermopolis, then a wool mid layer (got some merino from when I was in New Zealand) and then either a hard shell or a soft shell with a lightweight cheapo windbreaker. Need to read up more on soft shells versus hard shells. Seems like its really a trade off of protection vs breathability. Leaning towards a soft shell since I think it will be more useful to me and I'm not expecting driving rain.

As far as sleeping bags, I don't think there will be any good places to rent one. I do expect to do more cold weather trips in future so it's not a loss really. I'm kinda big anyway so regular ones probably wont fit me anyway.

"Won't be hauling a dslr."

That'll take all of the fun out of it if you don't have a good camera.

The one thing about the volcanoes that most people do not consider is water. There is virtually zero running water anywhere up high. At the cabins, I think that rainwater is collected off the metal roofs. However, if you are out on your own somewhere, there is zero water except for what you carry. That can be a big problem.

I was going to be up there for four days, worst case, and I figured that I could get by on one gallon of water per day, so I had to carry four gallons of water (fresh from the tap at the Hilo Airport). Do the math, and that is about 32 pounds worth of water. Then add in ten pounds of camera gear, etc.

–B.G.–

If there's any possibility of rain beyond a drizzle, I think you need a rain jacket. But, that depends on the soft shell. Some are more waterproof than others. Make sure you know how much rain protection yours has. I'd bring both a soft shell and rain jacket.

Bring rain pants too.

youll want a puffy for stops and camp …

read the stuff under clothing here …

http://www.andy-kirkpatrick.com/articles/gear/