Western Mountaineering HighLite vs SummerLite

Sewn-thru vs baffled construction does result in a difference in overall warmth beyond the measured loft, unless the sewn-thru article is rediculously overstuffed. Also, note that the Summerlite has a draft tube along the zipper to seal out cold air whereas the Highlite does not.

However, we all sleep "warmer" or "cooler" based on our own metabalisms. If your impression of the Highlite's temperature rating should be 45, then I would suggest you jump to the Megalight. It has more stuffing and it has a collar to keep heat in as neither the other two models have. It weighs about 4 oz. more.

I have the Megalite (long). It has a larger interior volume which I need at 6'2", a just shy of 200 lbs. In my experience, the 32 degree rating is spot on with wearing heavy-weight wool long-johns. I can extend that into the upper 20's with an insulated top. YMMV.

My wife who sleep "colder" than me, has the Ultralite (20 degree rating, small volume) and she is comfy with wool long-johns to just below freezing and adds an insulated top into the 20's. She says that she is "toasty".

Hi Bill,
have been using a Summerlite the past 10 weekends with lows in the lower 40's/ mid 30's & have been comfortable the whole time, this past weekend used a Cocoon Hoody to boost comfort in a bivy when temps dropped off fast & worked really great.
Have recently seen the newer Highlite's at a local outfitter and it seemed pretty close loft wise to the Summerlite that I purchased last season.

Not sure if WM would update your bag for you but might be worth a phone call

I have owned the WM Highlite and currently own the Summerlite and Ultralite. I found the Highlite comfortable to the mid forties. I find the Summerlite comfortable to the upper thirties and my Ultralite comfortable to the upper twenties. I am, as you can see, a very cold sleeper. Although the Highlite is a beautiful bag and very light, I find the Summerlite with its baffled construction, draft tube, and full length zipper to be a more versatile bag.

As far as I am aware, there was no actual change to the Higlite, just a change in temperature rating due to the overwhelming response that the bag was very conservatively rated and with more competition from the Marmot Atom etc. Although I wouldn't have dare taken mine down this low, I know a hiker that took his Highlite down to the lower twenty's with a few light layers on.

I have used a Highlite for 3 seasons as a 3 season bag and have had it down to 19 degrees(a cold snap in the southern Sierra 2 yrs ago), fully "BMW Cocooned" plus my Golite Reeds, a Powerstretch balaclava, and Mountain Hardwear cap. I was on the edge of my comfort zone but made it just fine. In general, I would say it is good for warm sleepers down to its advertized rating, based on many other nights use. I have used my newly purchased Summerlite on one trip this year in temperatures down to 30 degrees and was comfortable with a base layer, Ibex Woolie top and bottom, Mountain Hardwear cap, plus a windshirt. So I'd guess the Summerlite rating is spot on, too, for warm sleepers. But I feel like I have a bit more slack with the Summerlite, due to the draft tube and extra loft. Just one warm sleeper's experience. YMMV

All,
Thanks for the information. It seems that the SummerLite might be a better bag for me, although I have an UltraLite as well, I just resist carrying the extra weight if I don’t have to. I do sleep well with the HL + Cocoon P/O down to low 40’s and will probably just add Cocoon pants for the next trip.

That was interesting to hear the WM did not change the HL bag to lower its temp. rating, they just lowered the rating.

Jim,
Since you camp in the Whites, do you use the AMC sites with tent platforms at all? If so do you find it warmer or colder sleeping on the platform vs. the ground? I initially thought that the ground would be colder, but wonder if the platform gets colder because as the air temp. drops, the platform (with air blowing under it) would cool off faster than the ground.

Thanks,
Bill

Hi Bill,
Most definitely sleep at AMC sites in the Whites, usually are subject to whats available for overnight use & try and use overflow area when sites are packed in. Platforms have always seemed warmer to me then the ground up there, good point about wind blowing up from below, have recently been using a GG gear 1/8"x 59" pad which would explain why I have not noticed any breeze coming up from below.