Down jackets for 3 season use – how much down?

I have a montbell mirage and it's very warm, often worth taking. The problem is it can be too warm at times. In the evenings when it cools down the mirage can be a little too warm, but just sitting around in your windshirt isn't warm enough. Or if I take a break to wait out a thunderstorm, it will be cool out but the mirage can be too warm. So I am tempted to bring a light fleece to fill in that gap. The jacket is fine once the sun goes all the way down, then it's perfect.

"So who thinks a 4oz or 5oz down fill jacket is worth it? The Montbell Mirage jacket looks interesting with over 5oz of fill and less than 13oz in total weight. Seems like the extra fill would be worth the very minor weight penalty."

Since you're most of the way there with your Cerium, maybe consider picking up a Montbell Extreme Lite jacket. That would give you a lot more flexibility for roughly the same weight, and probably save you a few bucks in the bargain.

You could add a vest to what you have and get all kinds of combos out of that.

I have a Golite Bitterroot that has worked well for me. Specs show 5.3 ozs fill and 13 ozs Total Weight. Mine is right at 13ozs. Not sure if there are any still floating around out there?

Worked well in Wind River Range and Spring outing on the Superior Hiking Trail. I tend to be on the colder side and seem to be the first one to pull out their puffy.

Packs super small and great loft. I have been concerned about durability, but no issues yet.

more down…and leave one mid layer at home. A lightweight down jacket that requires a fleece or another down vest to supplement for warmth just seems wrong. Go big!

I really like the Mirage, it's the most used of my down jackets.
The box wall makes a big differnce in warmth.

I had a custom puffy made for me by Goose Feet and went with 4.3 ounces. It would be considered a boxy large….slightly long with sewn through baffle construction, hood and handwarmer pockets. I absolutely love that thing.

I have no regrets…. it is literally perfect. I left it home on my summer trip across the Olympics but it was smoking hot this year. I've taken it on every other trip and never thought it was anything but perfect.

withdrawn

Just a thought, but since you already have a nice down jacket, a pair of UL down pants might take you further than upping the fill weight in your jacket by a couple oz. A pair of borah gear or Luke's ultralight would cost you less than a mirage and would only be a couple oz heavier paired with your cerium. If you already bring long underwear the down pants could replace them for little weight gain, too.

The Mirage is an oven and IMHO it is way too hot for 3 season. I stick with a Montebell Ex Light June-October, and in the shoulder months I find I can get a massive increase in warmth by micro-tweaking the other layers: thicker larger beanie, thicker gloves, thicker thermals, and use a second shirt as a scarf, all for a very minor weight increase. You also probably know this, but if your bird jacket is a loose fit, you may not be getting the warmth you should expect with that much down.

Thanks for the feedback all. The dead bird jacket is a snug fit and providing the warmth it should. I was more interested in other peoples' configurations than I was slightly chilly one night and wanting to switch.

The Mirage being too warm for 3 season use is good feedback. I guess I need to figure out what that wild-card mid layer will be to compliment my puffy. I've got:

a nano puff synthetic vest – 8oz
a 100 weightt fleece (Andrew Sku loves these) – also about 8oz
a dead bird wind shirt – about 5.5 oz

The fleece is nice because i can wear it in the AM/evening whilst chilly but not too cold. The vest I could do the same with and both of these would layer nicely under my puffy.

The windshirt everyone seems to love but not sure where that goes with the puffy. This seems more useful on summit bids where it is a bit windier. The fleece/windshirt wouldn't seem to be as effective here.

Given that down is way lighter and warmer than the material in a Nano puff or fleece (8 oz.)–wouldn't two more ounces of down obviate the need of a nano, be warmer and save weight? One piece to rule them all etc.

I understand that more pieces=more versatility. I guess I just unzip my down jacket and then take it off when it warms in the morning. Come evening, I like a lot of warmth! (but I run cold.)

The older EB 1st Ascent jacket in my avatar is my 3 season jacket.

Good by itself on days/nights when there is no breeze land great under my eVent parka. Also increases my overstuffed WM Megalite's temp rating to 10 F. when I wear light insulating pants.

EB's newer 1st Ascent jackets are filled with DriDown treated down, something I wish mine had.

I am thinking of buying a down hood to go with it in colder weather.

NOTE: For even colder weather I wear a 100 weight fleece vest beneath it. With both collars zipped to my chin and a double layer (fleece & knit) Peruvian hat I'm very warm with the eVent parka over everything.

I think a 100 weight fleece layered under a 3-ish ounce down jacket is pretty much perfect for multi day trips in the Sierra. Layered together they'll offer adequate warmth while gazing at the sunset & alpenglow. If a cold front moves in while you're on the move, like hurrying over that high pass in the afternoon, you'll surely appreciate having the fleece.

My knee jerk says 5oz class jacket is a bit too much for summer in sierras,but everyone is different.

Im cold natured, low bodyfat. My exlite and long john top are fine down to freezing. I dont spend much time sitting aroynd though. Worked fine for a few subfreezing hours on Whitney too.

For temps in 20s id go for the mirage. Or a custom. Im looking at doing just that.

If you get cold, you can always wrap up in quilt or bag