Atom HW (aka AR) vs Atom (aka LT): Only Arcs with mesh panels

Going from top to bottom: Atom SL (soon to be called Atom Lightweight), Atom (formerly LT) and Atom Heavyweight (formerly AR). Click on image to view their side-by-side comparison on arcteryx.com.

I've got all Atoms. Including the new versions for Winter 2024 season.

Summary

It's like comparing apples to oranges.

Atom Hw is designed for stationary or low-output use at most. It's much warmer and wind resistant than Atom.

Atom, on the other hand, is for high output activities. It provides much better breathability and mobility compared to Atom Hw.

This, in my opinion, is what your decision should primarily be based on.

Links:

Warmth

There's one thing that makes Atom HW unique in terms of the distribution of insulation.

It might not be a game changer but I personally really like the idea.

Temperature ratings of Arc'teryx jackets

Name	Est. Temp (F/C)	Review	Pit venting?	Two way zipper?	Stuffs into itself?	Type	Fill Power (in3/oz)	Fill Weight (g)	Fill Volume (in3)	Synthetic Fill	Synth. Fill Weight	Face Fabric	Activity	Fit	Weight	Length (CB)
Arc'teryx Alpha Parka (Men's - Women's)	-18/-28	Review	No	Yes	Yes	Down	850	296	8,875	Coreloft	90 g/m²	N30r 2L GoreTex Infinium	Climbing	Regular	805 g / 1 lb 12.4 oz	86 cm / 34 in
Arc'teryx Alpha Lightweight (Men's - Women's)	5/-15		No	Yes	Yes	Down	850	117	3,508	Coreloft Compact	40 g/m²	Hadron 2L Gore-Tex Infinium	Climbing	Regular	540 g / 1 lb 3 oz	79.5 cm / 31.25 in
Arc'teryx Atom (aka LT) ( Men's - Women's)	43/6	Review	Yes, mesh	No	No	Synthetic	N/A	N/A	N/A	Coreloft Continuous	60 g/m²	20D Tyono	All Round	Trim	375 g / 13.2 oz	74 cm / 29.1 in
Arc'teryx Atom Heavyweight (aka AR) (Men's - Women's)	18/-8	Review	Yes, mesh	No	No	Synthetic	N/A	N/A	N/A	Coreloft Continuous	120 g/m2 + 80 g/m2 + 60 g/m2	30D Tyono	All Round	Regular	475 g / 1 lb	74 cm / 29.1 in
Arc'teryx Atom Lightweight (aka SL) (Men's - Women's)	52/11	Review	Yes, mesh	No	No	Synthetic	N/A	N/A	N/A	Coreloft Compact	40 g/m²	20D Tyono	All Round	Trim	270 g / 9.5 oz	72 cm / 28.3 in
Arc'teryx Beta Down Insulated (Men's)	0/-18		Yes	Yes	No	Parka	850	126	3,778	Coreloft	80 g/m²	2L 40D Gore-Tex	All Round	Regular	760 g / 1 lb 10.8 oz	79 cm / 31 in
Arc'teryx Beta Insulated (Men's)	21/-6	Review	Yes, zips	Yes	No	Parka	N/A	N/A	N/A	Coreloft Continuous	80 g/m²	2L 40D Gore-Tex	All Round	Regular	680 g / 1 lb 8 oz	78.5 cm / 31 in
Arc'teryx Beta Insulated Coat (Women's)	16/-9	Review	No	Yes	No	Parka	N/A	N/A	N/A	Coreloft	80 g/m² + 120 g/m²	2L 40D Gore-Tex	Around Town	Regular	600 g / 1 lb 5.2 oz	86 cm / 34 in
Arc'teryx Cerium (aka LT) (Men's - Women's)	26/-3	Review	No	No	Yes	Down	850	113	3,388	Coreloft	80 + 100 g/m²	Arato 15	All Round	Trim	335 g / 11.8 oz	72 cm / 28.3 in
Arc'teryx Cerium Hybrid (Women's)	44/7		No	No	Yes	Down	850	44	1,319	Coreloft	40 + 100 g/m²	Arato 15 + Fortius Air 50	All Round	Trim	260 g / 9.2 oz	70 cm / 27.5 in
Arc'teryx Coelle (Women's)	14/-10		No	Yes	No	Parka	N/A	N/A	N/A	Coreloft	98 g/m²	40D 2L Gore-Tex	Around Town	Regular	435g / 15.3 oz	70 cm / 27.5 in
Arc'teryx Liatris (Women's)	5/-15		No	No	No	Parka	850	93	2,788	Climashield	80 g/m2 + 60 g/m2	70D 3L Gore-Tex	Around Town	Regular	890 g / 1 lb 15.4 oz	75 cm / 29.5 in
Arc'teryx Liatris Parka (Women's)	2/-17		No	No	No	Parka	850	136	4,078	Climashield	80 g/m2 + 60 g/m2	70D 3L Gore-Tex	Around Town	Regular	1.093 kg / 2 lb 6.6 oz	109 cm / 43 in
Arc'teryx Nuclei (aka FL) ( Men's - Women's)	32/0	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	Coreloft Continuous	65 g/m²	Arato 10r	All Round	Regular	325 g / 11.5 oz	75 cm / 29.5 in
Arc'teryx Nuclei SV (Women's)	5/-15	Review	No	Yes	Yes	Synthetic	N/A	N/A	N/A	Coreloft Continuous	190 g/m2 + 90 g/m2	Arato 15	All Round	Regular	600 g / 1 lb 5.2 oz	81 cm / 31.8 in
Arc'teryx Patera (Women's)	21/-6	Review	No	Yes	No	Parka	750	67	1,773	Coreloft	60 + 80 g/m²	2L Gore-Tex	Around Town	Trim	867 g / 1 lb 14.6 oz	99 cm / 39 in
Arc'teryx Patera Long (Women's)	0/-18		No	Yes	No	Parka	750	204	5,397	Coreloft	60 + 80 g/m²	2L Gore-Tex	Around Town	Regular	1.1 kg / 2 lb 6.8 oz	117.5 cm / 46.25 in
Arc'teryx Proton Lightweight (aka FL) (Men's - Women's)	48/9	Review	No	No	No	Synthetic	N/A	N/A	N/A	Octa Loft	94 g/m²	Fortius Air 20	Climbing	Trim	343 g / 12.1 oz	75 cm / 29.5 in
Arc'teryx Therme Parka (Men's)	5/-15	Review	No	Yes	No	Parka	750	120	3,175	Coreloft	60 + 80 g/m²	P75d Polyester	Around Town	Regular	991 g / 2 lb 3 oz	85 cm / 33.5 in
Arc'teryx Therme SV (Men's)	-11/-24	Review	No	Yes	No	Parka	750	211	5,582	Coreloft	60 g/m²	2L Gore-Tex	Around Town	Regular	1.072 kg / 2 lb 5.8 oz	96 cm / 37.75 in
Arc'teryx Thorium ( Men's - Women's)	12/-11	Review	No	Yes	Yes	Down	750	140	3,704	Coreloft	80 + 140 g/m²	Arato 30	All Round	Regular	517 g / 1 lb 2.2 oz	71.5 cm / 28.1 in
Arc'teryx Thorium Parka (Women's)	-2/-19	Review	No	Yes	No	Down	750	209	5,529	Coreloft	80 + 140 g/m²	Arato 20	Around Town	Regular	610 g / 1 lb 5.5 oz	115.8 cm / 45.6 in
Arc'teryx Thorium SV (Men's)	3/-16		No	Yes	Yes	Down	750	169	4,471	Coreloft	80 + 140 g/m²	Arato 30 & 2L Gore-Tex Infinium	Around Town	Regular	645 g / 1 lb 6.8 oz	73 cm / 28.75 in
Arc'teryx Thorium SV Parka (Men's)	0/-18		No	Yes	No	Down	750	195	5,159	Coreloft	80 + 140 g/m²	Arato 30 & 2L Gore-Tex Infinium	Around Town	Regular	685 g / 1 lb 8.2 oz	85 cm / 33.5 in
Black Diamond Access Down (Men's - Women's)	7/-14		No	Yes	Yes	Down	700	155	3,827	N/A	N/A	30D ripstop nylon	All Round	Regular	442 g / 15.6 oz	76 cm / 29.75 in
Feathered Friends Eos(Men's - Women's)	8/-13		No	No	Yes	Down	900	105	3,333	N/A	N/A	Pertex Quantum	All Round	Regular	306 g / 10.8 oz	?
Feathered Friends Khumbu (Men's)	-17/-27		No	No	Yes	Down	900	378	12,000	Primaloft Gold	200 g	Pretex Shield XT	All Round	Regular	960 g / 2 lb 2 oz	?
Mountain Equipment Exo (Men's)	-10/-23		No	Yes	Yes	Down	800	265	7,478	N/A	N/A	Nylon	All Round	Regular	770 g / 1 lb 11.2 oz	79 cm / 31 in
Mountain Equipment K7 (Men's)	-13/-25		No	Yes	Yes	Down	800	300	8,466	N/A	N/A	30D Drilite	All Round	Regular	820 g / 1 lb 13 oz	76 cm / 30 in
Mountain Hardwear GW/2 (Men's - Women's)	28/-2		No	No	Yes	Down	800	85	2,399	N/A	N/A	10D Ripstop Nylon	All Round	Trim	250 g / 8.8 oz	70 cm / 27.5 in
Outdoor Research Sup. Alp. (Men's - Women's)	3/-16		No	Yes	No	Down	800	182	5,136	N/A	N/A	30D Pertex Quantum Pro	All Round	Regular	825 g / 1 lb 13.1 oz	85 cm / 33.5 in
Patagonia AlpLight (Men's - Women's)	36/2		No	No	Yes	Down	800	100	2,822	N/A	N/A	0.8 oz 10D polyester	All Round	Slim	270 g / 9.5 oz	74 cm / 29 in
Patagonia AlpLoft (Men's)	-10/-23		No	Yes	Yes	Down	800	295	8,325	N/A	N/A	Pertex Quantom	All Round	Regular	680 g / 1 lb 8 oz	81 cm / 31.8 in
Patagonia DAS (Men's - Women's)	10/-12	Review	No	Yes	Yes	Synthetic	N/A	N/A	N/A	PrimaLoft Gold Insulation Eco	133 + 40 g	Pertex Quantum Pro	All Round	Regular	555 g / 1 lb 3.6 oz	84 cm / 33 in
Patagonia DAS Light(Men's)	34/1	Review	No	Yes	Yes	Synthetic	N/A	N/A	N/A	PlumaFill	65 g	10D Pertex Quantum Pro	All Round	Regular	320 g / 11.3 oz	77 cm / 30.5 in
Patagonia Down Sweater (Men's - Women's)	23/-5	Review	No	No	Yes	Down	800	150	4,233	N/A	N/A	1.4 oz 20x30D polyester	All Round	Regular	428 g / 15.1 oz	67 cm / 26.25 in
Patagonia Downdrift (Men's - Women's)	18/-8		No	No	No	Down	600	279	5,905	N/A	N/A	4.2 oz polyester	Around Town	Regular	1.014 kg / 2 lb 3.8 oz	?
Patagonia Fitz Roy (Men's - Women's)	14/-10		No	No	Yes	Down	800	128	3,612	N/A	N/A	20D Nylon	All Round	Regular	632 g / 1lb 6.3 oz	74 cm / 29 in
Patagonia Isthmus (Men's)	36/2		No	No	No	Parka	N/A	N/A	N/A	ThermoGreen	60 g	4.2 oz polyester	Around Town	Regular	895 g / 1 lb 15.6 oz	70 cm / 27.5 in
Patagonia Jackson Glacier (Men's - Women's)	12/-11	Review	No	Yes	No	Down	700	141	3,482	N/A	N/A	3.6 oz 50D polyester	Around Town	Regular	880 g / 1 lb 15 oz	79 cm / 31 in
Patagonia Jackson Glacier Parks ( Women's)	7/-14		No	No	No	Parka	700	218	5,383	N/A	N/A	50D Polyester	Around Town	Regular	1.142 kg / 2 lb 8.3 oz	?
Patagonia Micro Puff (Men's - Women's)	37/3	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	PlumaFill	65 g	Pertex Quantum	All Round	Regular	298 g / 10.5 oz	75 cm / 29.5 in
Patagonia Nano Air (Men's - Women's)	39/4	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	FullRange	60 g	33D nylon ripstop	All Round	Trim	401 g / 14.14 oz	?
Patagonia Nano Air Light Hybrid (Men's - Women's)	50/10		No	No	No	Synthetic	N/A	N/A	N/A	FullRange	40 g	20D nylon ripstop	All Round	Trim	335 g / 11.8 oz	?
Patagonia Nano Puff (Men's - Women's)	41/5	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	PrimaLoft Gold Insulation Eco	60 g	22D Polyester	All Round	Regular	363 g / 12.8 oz	71.5 cm / 28 in
Patagonia Silent Down (Men's - Women's)	26/-3	Review	No	No	No	Down	700	109	2,691	N/A	N/A	2.2 oz polyester	Around Town	Regular	585 g / 1 lb 4.7 oz	74 cm / 29 in
Patagonia Stormshadow (Men's)	0/-18		No	No	No	Parka	700	259	6,395	N/A	N/A	75D Polyester	Around Town	Regular	1.182 kg / 2 lb 9.7 oz	?
Patagonia Tres 3-in-1Patagonia Tres 3-in-1 (Men's - Women's)	8/-13	Review	No	No	No	Parka	700	118	2,914	N/A	N/A	5.5 oz polyester	Around Town	Regular	1.307 kg / 2 lb 14.1 oz	85 cm / 33.5 in
Patagonia Vosque 3-in-1 (Women's)	10/-12	Review	No	No	No	Parka	N/A	N/A	N/A	ThermoLite	100 g	65% nylon, 35% polyester	Around Town	Regular	1.360 kg / 3 lb	90 cm / 35.5 in
Rab Electron Pro (Men's - Women's)	5/-15		No	Yes	Yes	Down	800	180	5,079	N/A	N/A	20D Pertex Quantum Pro	All Round	Regular	525 g / 1 lb 2.5 oz	74 cm / 29 in
Rab Infinity Alpine (Men's)	5/-15		No	Yes	Yes	Down	800	175	4,938	N/A	N/A	30D & 13D Gore-Tex Infinium	All Round	Regular	551 g / 1 lb 3.4 oz	76.5 cm / 30.1 in
Rab Infinity Microlight (Men's - Women's)	19/-7		No	No	Yes	Down	700	146	3,605	N/A	N/A	13D Gore-Tex Infinium	All Round	Regular	452 g / 15.9 oz	74 cm / 29.1 in
Rab Microlight Alpine (Men's - Women's)	7/-14		No	No	Yes	Down	700	153	3,778	N/A	N/A	30D Pertex Quantum	All Round	Regular	466 g / 1 lb 0.5 oz	72 cm / 28.5 in
Rab Neutrino Pro (Men's - Women's)	-2/-19		No	Yes	Yes	Down	800	212	5,982	N/A	N/A	20D Pertex Quantum Pro	All Round	Regular	585 g / 1 lb 8.6 oz	77 cm / 30.3 in
Rab Positron Pro (Men's)	-13/-25		No	Yes	Yes	Down	800	300	8,466	N/A	N/A	40D Pertex Quantum Pro	All Round	Regular	740 g / 1 lb 10 oz	85 cm / 33.5 in
REI Magma 850 Hoodie 2.0 (Men's - Women's)	14/-10		No	No	Yes	Down	850	120	3,598	N/A	N/A	Pertex mini ripstop nylon	All Round	Regular	340 g / 13.75 oz	74 cm / 29.25 in

Assumptions: Worn over a thin shirt, no output, no precipitation, light to no wind. Values are always for size M and for men's, except for women's-only items.

Primary use of this spectrum is for comparison, rather than figuring out absolute temp ratings.

Working principles of insulated jackets: https://outdoorcrunch.com/jackets/
CLO Values: https://outdoorcrunch.com/clo-values/
Best Arc'teryx jackets: https://outdoorcrunch.com/best-arcteryx-jacket/
Best sellers (new pages)
- https://arcteryx.com/us/en/c/mens/p/best-sellers
- https://arcteryx.com/us/en/c/womens/p/best-sellers

Performance ratings of Arc'teryx synthetics

Name	Est. Temp (F/C)	Review	Pit venting?	Two way zipper?	Stuffs into itself?	Type	Fill Power (in3/oz)	Fill Weight (g)	Fill Volume (in3)	Synthetic Fill	Synth. Fill Weight	Face Fabric	Activity	Fit	Weight	Length (CB)
Arc'teryx Alpha Parka (Men's - Women's)	-18/-28	Review	No	Yes	Yes	Down	850	296	8,875	Coreloft	90 g/m²	N30r 2L GoreTex Infinium	Climbing	Regular	805 g / 1 lb 12.4 oz	86 cm / 34 in
Arc'teryx Alpha Lightweight (Men's - Women's)	5/-15		No	Yes	Yes	Down	850	117	3,508	Coreloft Compact	40 g/m²	Hadron 2L Gore-Tex Infinium	Climbing	Regular	540 g / 1 lb 3 oz	79.5 cm / 31.25 in
Arc'teryx Atom (aka LT) ( Men's - Women's)	43/6	Review	Yes, mesh	No	No	Synthetic	N/A	N/A	N/A	Coreloft Continuous	60 g/m²	20D Tyono	All Round	Trim	375 g / 13.2 oz	74 cm / 29.1 in
Arc'teryx Atom Heavyweight (aka AR) (Men's - Women's)	18/-8	Review	Yes, mesh	No	No	Synthetic	N/A	N/A	N/A	Coreloft Continuous	120 g/m2 + 80 g/m2 + 60 g/m2	30D Tyono	All Round	Regular	475 g / 1 lb	74 cm / 29.1 in
Arc'teryx Atom Lightweight (aka SL) (Men's - Women's)	52/11	Review	Yes, mesh	No	No	Synthetic	N/A	N/A	N/A	Coreloft Compact	40 g/m²	20D Tyono	All Round	Trim	270 g / 9.5 oz	72 cm / 28.3 in
Arc'teryx Beta Down Insulated (Men's)	0/-18		Yes	Yes	No	Parka	850	126	3,778	Coreloft	80 g/m²	2L 40D Gore-Tex	All Round	Regular	760 g / 1 lb 10.8 oz	79 cm / 31 in
Arc'teryx Beta Insulated (Men's)	21/-6	Review	Yes, zips	Yes	No	Parka	N/A	N/A	N/A	Coreloft Continuous	80 g/m²	2L 40D Gore-Tex	All Round	Regular	680 g / 1 lb 8 oz	78.5 cm / 31 in
Arc'teryx Beta Insulated Coat (Women's)	16/-9	Review	No	Yes	No	Parka	N/A	N/A	N/A	Coreloft	80 g/m² + 120 g/m²	2L 40D Gore-Tex	Around Town	Regular	600 g / 1 lb 5.2 oz	86 cm / 34 in
Arc'teryx Cerium (aka LT) (Men's - Women's)	26/-3	Review	No	No	Yes	Down	850	113	3,388	Coreloft	80 + 100 g/m²	Arato 15	All Round	Trim	335 g / 11.8 oz	72 cm / 28.3 in
Arc'teryx Cerium Hybrid (Women's)	44/7		No	No	Yes	Down	850	44	1,319	Coreloft	40 + 100 g/m²	Arato 15 + Fortius Air 50	All Round	Trim	260 g / 9.2 oz	70 cm / 27.5 in
Arc'teryx Coelle (Women's)	14/-10		No	Yes	No	Parka	N/A	N/A	N/A	Coreloft	98 g/m²	40D 2L Gore-Tex	Around Town	Regular	435g / 15.3 oz	70 cm / 27.5 in
Arc'teryx Liatris (Women's)	5/-15		No	No	No	Parka	850	93	2,788	Climashield	80 g/m2 + 60 g/m2	70D 3L Gore-Tex	Around Town	Regular	890 g / 1 lb 15.4 oz	75 cm / 29.5 in
Arc'teryx Liatris Parka (Women's)	2/-17		No	No	No	Parka	850	136	4,078	Climashield	80 g/m2 + 60 g/m2	70D 3L Gore-Tex	Around Town	Regular	1.093 kg / 2 lb 6.6 oz	109 cm / 43 in
Arc'teryx Nuclei (aka FL) ( Men's - Women's)	32/0	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	Coreloft Continuous	65 g/m²	Arato 10r	All Round	Regular	325 g / 11.5 oz	75 cm / 29.5 in
Arc'teryx Nuclei SV (Women's)	5/-15	Review	No	Yes	Yes	Synthetic	N/A	N/A	N/A	Coreloft Continuous	190 g/m2 + 90 g/m2	Arato 15	All Round	Regular	600 g / 1 lb 5.2 oz	81 cm / 31.8 in
Arc'teryx Patera (Women's)	21/-6	Review	No	Yes	No	Parka	750	67	1,773	Coreloft	60 + 80 g/m²	2L Gore-Tex	Around Town	Trim	867 g / 1 lb 14.6 oz	99 cm / 39 in
Arc'teryx Patera Long (Women's)	0/-18		No	Yes	No	Parka	750	204	5,397	Coreloft	60 + 80 g/m²	2L Gore-Tex	Around Town	Regular	1.1 kg / 2 lb 6.8 oz	117.5 cm / 46.25 in
Arc'teryx Proton Lightweight (aka FL) (Men's - Women's)	48/9	Review	No	No	No	Synthetic	N/A	N/A	N/A	Octa Loft	94 g/m²	Fortius Air 20	Climbing	Trim	343 g / 12.1 oz	75 cm / 29.5 in
Arc'teryx Therme Parka (Men's)	5/-15	Review	No	Yes	No	Parka	750	120	3,175	Coreloft	60 + 80 g/m²	P75d Polyester	Around Town	Regular	991 g / 2 lb 3 oz	85 cm / 33.5 in
Arc'teryx Therme SV (Men's)	-11/-24	Review	No	Yes	No	Parka	750	211	5,582	Coreloft	60 g/m²	2L Gore-Tex	Around Town	Regular	1.072 kg / 2 lb 5.8 oz	96 cm / 37.75 in
Arc'teryx Thorium ( Men's - Women's)	12/-11	Review	No	Yes	Yes	Down	750	140	3,704	Coreloft	80 + 140 g/m²	Arato 30	All Round	Regular	517 g / 1 lb 2.2 oz	71.5 cm / 28.1 in
Arc'teryx Thorium Parka (Women's)	-2/-19	Review	No	Yes	No	Down	750	209	5,529	Coreloft	80 + 140 g/m²	Arato 20	Around Town	Regular	610 g / 1 lb 5.5 oz	115.8 cm / 45.6 in
Arc'teryx Thorium SV (Men's)	3/-16		No	Yes	Yes	Down	750	169	4,471	Coreloft	80 + 140 g/m²	Arato 30 & 2L Gore-Tex Infinium	Around Town	Regular	645 g / 1 lb 6.8 oz	73 cm / 28.75 in
Arc'teryx Thorium SV Parka (Men's)	0/-18		No	Yes	No	Down	750	195	5,159	Coreloft	80 + 140 g/m²	Arato 30 & 2L Gore-Tex Infinium	Around Town	Regular	685 g / 1 lb 8.2 oz	85 cm / 33.5 in
Black Diamond Access Down (Men's - Women's)	7/-14		No	Yes	Yes	Down	700	155	3,827	N/A	N/A	30D ripstop nylon	All Round	Regular	442 g / 15.6 oz	76 cm / 29.75 in
Feathered Friends Eos(Men's - Women's)	8/-13		No	No	Yes	Down	900	105	3,333	N/A	N/A	Pertex Quantum	All Round	Regular	306 g / 10.8 oz	?
Feathered Friends Khumbu (Men's)	-17/-27		No	No	Yes	Down	900	378	12,000	Primaloft Gold	200 g	Pretex Shield XT	All Round	Regular	960 g / 2 lb 2 oz	?
Mountain Equipment Exo (Men's)	-10/-23		No	Yes	Yes	Down	800	265	7,478	N/A	N/A	Nylon	All Round	Regular	770 g / 1 lb 11.2 oz	79 cm / 31 in
Mountain Equipment K7 (Men's)	-13/-25		No	Yes	Yes	Down	800	300	8,466	N/A	N/A	30D Drilite	All Round	Regular	820 g / 1 lb 13 oz	76 cm / 30 in
Mountain Hardwear GW/2 (Men's - Women's)	28/-2		No	No	Yes	Down	800	85	2,399	N/A	N/A	10D Ripstop Nylon	All Round	Trim	250 g / 8.8 oz	70 cm / 27.5 in
Outdoor Research Sup. Alp. (Men's - Women's)	3/-16		No	Yes	No	Down	800	182	5,136	N/A	N/A	30D Pertex Quantum Pro	All Round	Regular	825 g / 1 lb 13.1 oz	85 cm / 33.5 in
Patagonia AlpLight (Men's - Women's)	36/2		No	No	Yes	Down	800	100	2,822	N/A	N/A	0.8 oz 10D polyester	All Round	Slim	270 g / 9.5 oz	74 cm / 29 in
Patagonia AlpLoft (Men's)	-10/-23		No	Yes	Yes	Down	800	295	8,325	N/A	N/A	Pertex Quantom	All Round	Regular	680 g / 1 lb 8 oz	81 cm / 31.8 in
Patagonia DAS (Men's - Women's)	10/-12	Review	No	Yes	Yes	Synthetic	N/A	N/A	N/A	PrimaLoft Gold Insulation Eco	133 + 40 g	Pertex Quantum Pro	All Round	Regular	555 g / 1 lb 3.6 oz	84 cm / 33 in
Patagonia DAS Light(Men's)	34/1	Review	No	Yes	Yes	Synthetic	N/A	N/A	N/A	PlumaFill	65 g	10D Pertex Quantum Pro	All Round	Regular	320 g / 11.3 oz	77 cm / 30.5 in
Patagonia Down Sweater (Men's - Women's)	23/-5	Review	No	No	Yes	Down	800	150	4,233	N/A	N/A	1.4 oz 20x30D polyester	All Round	Regular	428 g / 15.1 oz	67 cm / 26.25 in
Patagonia Downdrift (Men's - Women's)	18/-8		No	No	No	Down	600	279	5,905	N/A	N/A	4.2 oz polyester	Around Town	Regular	1.014 kg / 2 lb 3.8 oz	?
Patagonia Fitz Roy (Men's - Women's)	14/-10		No	No	Yes	Down	800	128	3,612	N/A	N/A	20D Nylon	All Round	Regular	632 g / 1lb 6.3 oz	74 cm / 29 in
Patagonia Isthmus (Men's)	36/2		No	No	No	Parka	N/A	N/A	N/A	ThermoGreen	60 g	4.2 oz polyester	Around Town	Regular	895 g / 1 lb 15.6 oz	70 cm / 27.5 in
Patagonia Jackson Glacier (Men's - Women's)	12/-11	Review	No	Yes	No	Down	700	141	3,482	N/A	N/A	3.6 oz 50D polyester	Around Town	Regular	880 g / 1 lb 15 oz	79 cm / 31 in
Patagonia Jackson Glacier Parks ( Women's)	7/-14		No	No	No	Parka	700	218	5,383	N/A	N/A	50D Polyester	Around Town	Regular	1.142 kg / 2 lb 8.3 oz	?
Patagonia Micro Puff (Men's - Women's)	37/3	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	PlumaFill	65 g	Pertex Quantum	All Round	Regular	298 g / 10.5 oz	75 cm / 29.5 in
Patagonia Nano Air (Men's - Women's)	39/4	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	FullRange	60 g	33D nylon ripstop	All Round	Trim	401 g / 14.14 oz	?
Patagonia Nano Air Light Hybrid (Men's - Women's)	50/10		No	No	No	Synthetic	N/A	N/A	N/A	FullRange	40 g	20D nylon ripstop	All Round	Trim	335 g / 11.8 oz	?
Patagonia Nano Puff (Men's - Women's)	41/5	Review	No	No	Yes	Synthetic	N/A	N/A	N/A	PrimaLoft Gold Insulation Eco	60 g	22D Polyester	All Round	Regular	363 g / 12.8 oz	71.5 cm / 28 in
Patagonia Silent Down (Men's - Women's)	26/-3	Review	No	No	No	Down	700	109	2,691	N/A	N/A	2.2 oz polyester	Around Town	Regular	585 g / 1 lb 4.7 oz	74 cm / 29 in
Patagonia Stormshadow (Men's)	0/-18		No	No	No	Parka	700	259	6,395	N/A	N/A	75D Polyester	Around Town	Regular	1.182 kg / 2 lb 9.7 oz	?
Patagonia Tres 3-in-1Patagonia Tres 3-in-1 (Men's - Women's)	8/-13	Review	No	No	No	Parka	700	118	2,914	N/A	N/A	5.5 oz polyester	Around Town	Regular	1.307 kg / 2 lb 14.1 oz	85 cm / 33.5 in
Patagonia Vosque 3-in-1 (Women's)	10/-12	Review	No	No	No	Parka	N/A	N/A	N/A	ThermoLite	100 g	65% nylon, 35% polyester	Around Town	Regular	1.360 kg / 3 lb	90 cm / 35.5 in
Rab Electron Pro (Men's - Women's)	5/-15		No	Yes	Yes	Down	800	180	5,079	N/A	N/A	20D Pertex Quantum Pro	All Round	Regular	525 g / 1 lb 2.5 oz	74 cm / 29 in
Rab Infinity Alpine (Men's)	5/-15		No	Yes	Yes	Down	800	175	4,938	N/A	N/A	30D & 13D Gore-Tex Infinium	All Round	Regular	551 g / 1 lb 3.4 oz	76.5 cm / 30.1 in
Rab Infinity Microlight (Men's - Women's)	19/-7		No	No	Yes	Down	700	146	3,605	N/A	N/A	13D Gore-Tex Infinium	All Round	Regular	452 g / 15.9 oz	74 cm / 29.1 in
Rab Microlight Alpine (Men's - Women's)	7/-14		No	No	Yes	Down	700	153	3,778	N/A	N/A	30D Pertex Quantum	All Round	Regular	466 g / 1 lb 0.5 oz	72 cm / 28.5 in
Rab Neutrino Pro (Men's - Women's)	-2/-19		No	Yes	Yes	Down	800	212	5,982	N/A	N/A	20D Pertex Quantum Pro	All Round	Regular	585 g / 1 lb 8.6 oz	77 cm / 30.3 in
Rab Positron Pro (Men's)	-13/-25		No	Yes	Yes	Down	800	300	8,466	N/A	N/A	40D Pertex Quantum Pro	All Round	Regular	740 g / 1 lb 10 oz	85 cm / 33.5 in
REI Magma 850 Hoodie 2.0 (Men's - Women's)	14/-10		No	No	Yes	Down	850	120	3,598	N/A	N/A	Pertex mini ripstop nylon	All Round	Regular	340 g / 13.75 oz	74 cm / 29.25 in

Performance data axis of synthetic jackets (this table) and shell jackets (table below) are different. Don't compare them.

Best synthetic insulated jackets: https://outdoorcrunch.com/synthetic-insulated-jackets/

Performance ratings of Arc'teryx shells

Name	Activity	Temp (F/C)	Breathability	Weather Res.	Durability	Packability	Bottom line	Review	Pit zips?	Two way zipper?	Stuffs into itself?	Face Fabric	Fit	Weight	Length	Discontinued?
Alpha (aka AR) (Men's - Women's)	Climbing	N/A	8/10	9/10	8/10	4/10	Go-to climbing harshell.	Review	Yes	No	No	N40d & N80d Most Rugged 3L Gore-Tex Pro	Regular	430 g / 15.2 oz	79.5 cm / 31.25 in	No
Alpha SV (Men's - Women's)	Climbing	N/A	8/10	10/10	10/10	3/10	Strongest climbing hardshell.	Review	Yes	No	No	N100d Most Rugged 3L Gore-Tex Pro	Regular	510 g / 1 lb 2 oz	78 cm / 30.75 in	No
Beta (Men's - Women's)	All Round	N/A	6/10	7/10	7/10	8/10	Streamlined all-doer shell.	Review	No	No	No	N30p-X 3L Gore-Tex	Trim	300 g / 10.6 oz	76 cm / 30 in	No
Beta AR (Men's - Women's)	All Round	N/A	8/10	9/10	9/10	4/10	Go-to all-round harshell.	Review	Yes	No	No	N40d & N80d Most Rugged 3L Gore-Tex Pro	Regular	460 g / 1 lb	76 cm / 30 in	No
Beta AR StormHood (Men's - Women's)	All Round	N/A	8/10	9/10	9/10	4/10		Review	Yes	No	No	N40d & N80d Most Rugged 3L Gore-Tex Pro	Regular	460 g / 1 lb	76 cm / 30 in	No
Beta Coat (Women's)	All Round	N/A	6/10	5/10	No data	5/10			No	Yes	No	3L Gore-Tex	Regular	320 g / 11.3 oz	88 cm / 34.5 in	No
Beta Down Insulated (Men's)	All Round	0/-18	9/10	7/10	8/10	No data			Yes	Yes	No	2L 40D Gore-Tex	Regular	760 g / 1 lb 10.8 oz	79 cm / 31 in	No
Beta Insulated (Men's - Women's)	All Round	21/-6	9/10	7/10	8/10	No data	Go-to hybrid jacket.	Review	Yes	Yes	No	N40d 2L Gore-Tex	Regular	680 g / 1 lb 8 oz	78.5 cm / 31 in	No
Beta Insulated Coat (Women's)	All Round	16/-9	7/10	No data	No data	No data			No	Yes	No	N40d 2L Gore-Tex	Regular	600 g / 1 lb 5.2 oz	86 cm / 34 in	No
Beta Lightweight (Men's - Women's)	All Round	N/A	8/10	7/10	7/10	6/10		Review	Yes	No	No	N40p 3L Gore-Tex	Fitted	380 g / 13.4 oz	75 cm / 29.5 in	No
Beta LT (Men's - Women's)	All Round	N/A	7/10	7/10	8/10	6/10		Review	Yes	No	No	N40d 3L Gore-Tex	Fitted	395 g / 13.9 oz	76 cm / 30 in	No
Gamma (aka LT) (Men's - Women's)	All Round	N/A	7/10	3/10	7/10	3/10	Go-to softshell.	Review	No	No	No	Wee Burly Double Weave	Regular	545 g / 1 lb 3.2 oz	76 cm / 30 in	No
Gamma MX (Men's)	All Round	N/A	6/10	4/10	8/10	3/10	Strongest softshell.	Review	No	No	No	Fortius 2.0	Regular	555 g / 1 lb 3.6 oz	74 cm / 29.1 in	No
Norvan Shell (Men's)	Running	N/A	No data	No data	No data	No data			No	No	No	13D 3L Gore-Tex	Trim	190 g / 6.7 oz	73 cm / 28.75 in	No
Rush (Women's)	Skiing	N/A	8/10	9/10	9/10	3/10	Go-to ski jacket.	Review	Yes	No	No	N80p-X & N100p-X 3L Most Rugged Gore-Tex Pro	Regular	590 g / 1 lb 4.8 oz	79.5 cm / 31.25 in	No
Rush Insulated (Women's)	Skiing	16/-9	3/10	5/10	5/10	9/10		Review	No	No	Yes	Hadron 2L Gore-Tex Infinium	Regular	515 g / 1 lb 2.2 oz	79 cm / 31 in	Yes
Sabre (Men's)	Skiing	N/A	8/10	8/10	7/10	2/10		Review	Yes	No	No	N80p-X 3L Gore-Tex	Regular	705 g / 1 lb 8.9 oz	79 cm / 31 in	No
Sentinel (Women's)	Skiing	N/A	8/10	7/10	7/10	2/10	Go-to ski jacket.	Review	Yes	No	No	N70p 3L Gore-Tex	Regular	640 g / 1 lb 6.6 oz	73.7 cm / 29 in	No
Sentinel Insulated (Women's)	Skiing	21/-6	8/10	No data	No data	No data		Review	Yes	No	No	N80p 2L Gore-Tex	Regular	600 g / 1 lb 5.2 oz	79.8 cm / 31.5 in	No
Sentinel Relaxed (Women's)	Skiing	N/A	No data	No data	No data	No data			Yes	No	No	N80p 3L Gore-Tex	Regular	655 g / 1 lb 7.1 oz	?	No
Sidewinder (Women's)	Skiing	N/A	8/10	8/10	7/10	2/10			Yes	No	No	N80p 3L Gore-Tex	Regular	570 g / 1 lb 4.1 oz	?	No
Solano (Men's - Women's)	Around Town	N/A	No data	No data	No data	No data		Review	No	No	No	Gore-Tex Infinium	Relaxed	355 g / 12.5 oz	72 cm / 28.3 in	No
Squamish (Men's - Women's)	Running	N/A	5/10	4/10	7/10	9/10	Go-to running jacket.	Review	No	No	Yes	30D Tyono	Trim	140 g / 4.9 oz	77.5 cm / 30.5 in	No
Theriss Down (Women's)	Skiing	No data	7/10	6/10	7/10	2/10		Review	Yes	No	No	N80p 2L Gore-Tex	Regular	709 g / 1 lb 9 oz	63 cm / 24.8 in	No
Alpha FL (Men's - Women's)	Climbing	N/A	7/10	No data	No data	10/10			No	No	Yes	Hadron 3L Gore-Tex	Trim	209 g / 7.4 oz	76.5 cm / 30 in	Yes
Alpha IS (Men's)	Climbing	23/-5	7/10	5/10	No data	8/10			No	Yes	Yes	N40p-X 2L Gore-Tex	Regular	610 g / 1 lb 5.5 oz	78 cm / 30.75 in	Yes
Alpha SL (Men's - Women's)	Climbing	N/A	5/10	7/10	No data	9/10			No	No	Yes	N40p 3L Gore-Tex	Trim	326 g / 11.5 oz	77.5 cm / 30.5 in	Yes
Beta SV (Men's - Women's)	All Round	N/A	8/10	10/10	10/10	3/10	Strongest all-round harshell.	Review	Yes	No	No	N80p-X Most Rugged 3L Gore-Tex Pro	Regular	495 g / 1 lb 1.5 oz	79 cm / 31 in	Yes
Gamma SL (aka lightweight) (Men's - Women's)	All Round	N/A	7/10	2/10	6/10	5/10		Review	No	No	No	Fortius 1.0	Trim	310 g / 10.9 oz	74 cm / 29.1 in	Yes
Incendia (Women's)	Skiing	N/A	8/10	9/10	9/10	3/10		Review	Yes	No	No	NP100d 3L Gore-Tex	Trim	610 g / 1 lb 5.5 oz	79 cm / 31 in	Yes
Incendo (Men's)	Running	N/A	7/10	4/10	5/10	10/10		Review	No	No	Yes	Lumin	Trim	125 g / 4.4 oz	?	Yes
Incendo Airshell (Men's	Running	N/A	No data	No data	No data	No data			No	No	Yes	?	Trim	105 g / 3.7 oz	?	Yes
Incendo SL (Men's)	Running	N/A	7/10	4/10	4/10	10/10		Review	No	No	Yes	Permair 20 & Canim	Trim	80 g / 2.8 oz	73 cm / 28.75 in	Yes
Macai (Men's)	Skiing	5/-15	7/10	7/10	6/10	1/10		Review	Yes	No	No	N40p-X 3L Gore-Tex	Regular	990 g / 2 lb 2.9 oz	75 cm / 29.5 in	Yes
Macai Lightweight (aka LT) (Men's)	Skiing	8/-13	7/10	7/10	6/10	2/10		Review	Yes	No	No	N40p-X 3L Gore-Tex	Regular	855 g / 1 lb 14.2 oz	?	Yes
Macai Shell (Men's)	Skiing	N/A	No data	No data	No data	No data		Review	Yes	No	No	N80p-X 3L Gore-Tex	Regular	775 g / 1 lb 11.3 oz	?	Yes
Micon (Men's)	Skiing	N/A	No data	No data	No data	No data			Yes	No	No	N80p 3L Gore-Tex	Regular	685 g / 1 lb 8.2 oz	83 cm / 32.5 in	Yes
Micon Heather	Skiing	N/A	No data	No data	No data	No data			Yes	No	No	NP100-d 3L Gore-Tex	Regular	685 g / 1 lb 8.2 oz	83 cm / 32.5 in	Yes
Nodin (Men's - Women's)	Running	N/A	8/10	5/10	5/10	10/10			No	No	Yes	20D Tyono	Trim	130 g / 4.6 oz	75 cm / 29.5 in	Yes
Norvan LT (Men's - Women's)	Running	N/A	5/10	5/10	8/10	6/10			No	No	No	N13p 3L Gore-Tex	Trim	190 g / 6.7 oz	?	Yes
Norvan SL (Men's - Women's)	Running	N/A	7/10	6/10	8/10	8/10		Review	No	No	Yes	Gore-Tex Infinium	Trim	120 g / 4.2 oz	77 cm / 30.4 in	Yes
Norvan SL Ins. (Women's)	Running	39/4	No data	No data	No data	No data			No	No	Yes	Gore-Tex ShakeDry	Trim	270 g / 9.5 oz	71.5 cm / 28.1 in	Yes
Norvan Windshell (Men's	Running	N/A	No data	No data	No data	No data			No	No	Yes	Permeair 20	Trim	90 g / 3.2 oz	73 cm / 28.75 in	Yes
Procline (Men's)	Skiing	N/A	No data	No data	No data	No data			Yes	No	No	N70p Gore-Tex Infinium	Trim	720 g / 1 lb 9.4 oz	76 cm / 30 in	Yes
Ravenna (Women's)	Skiing	N/A	8/10	7/10	8/10	3/10		Review	Yes	No	No	N70s-4 3L Gore-Tex	Trim	725 g / 1 lb 9.6 oz	69.5 cm / 27.4 in	Yes
Ravenna LT (Women's)	Skiing	N/A	6/10	6/10	6/10	5/10		Review	Yes	No	No	N70p 3L Gore-Tex	Trim	540 g / 1 lb 3 oz	69 cm / 27.2 in	Yes
Sabre AR (Men's)	Skiing	N/A	7/10	8/10	7/10	7/10		Review	Yes	No	No	N70p 3L Gore-Tex	Regular	700 g / 1 lb 8.7 oz	79 cm / 31 in	Yes
Sabre Insulated (See related products)	Skiing	No data	7/10	No data	6/10	No data		Review	Yes	No	No	N80p 2L Gore-Tex	Regular	815 g / 1 lb 12.7 oz	76 cm / 30 in	Yes
Sabre LT (Men's)	Skiing	N/A	7/10	8/10	7/10	8/10		Review	Yes	No	No	N80p 3L Gore-Tex	Regular	660 g / 1 lb 7.3 oz	83 cm / 32.5 in	Yes
Sabre SV (Men's)	Skiing	N/A	10/10	10/10	10/10	1/10	Strongest ski jacket.	Review	Yes	Yes	No	N100d Most Rugged 3L Gore-Tex Pro	Regular	595 g / 1 lb 5 oz	85 cm / 33.5 in	No
Sentinel AR (Women's)	Skiing	N/A	7/10	8/10	7/10	7/10		Review	Yes	No	No	N70p 3L Gore-Tex	Regular	590 g / 1 lb 4.8 oz	72.5 cm / 28.5 in	Yes
Sentinel LT (Women's)	Skiing	N/A	7/10	8/10	7/10	8/10		Review	Yes	No	No	N80p 3L Gore-Tex	Regular	565 g / 1 lb 3.9 oz	73.5 cm / 29 in	Yes
Shashka Stretch (Women's)	Skiing	N/A	No data	No data	No data	No data			Yes	No	No	N70p Gore-Tex Infinium	Trim	670 g / 1 lb 7.6 oz	71 cm / 28 in	Yes
Trino SL (Men's)	Running	N/A	8/10	5/10	7/10	6/10		Review	No	No	No	Gore-Tex Infinium	Trim	340 g / 12 oz	74 cm / 29.1 in	Yes
Trino SL Anorak (Women's)	Running	N/A	8/10	7/10	8/10	7/10		Review	No	No	No	Gore-Tex Infinium	Trim	290 g / 10.2 oz	65 cm / 25.5 in	Yes
Venda Anorak (Women's)	Around Town	N/A	No data	No data	No data	No data			No	No	No	Gore-Tex	Relaxed	255 g / 9 oz	75.5 cm / 29.7 in	Yes
Zeta AR (Men's)	Hiking	N/A	7/10	8/10	7/10	4/10			Yes	No	No	3L Gore-Tex	Regular	425 g / 15 oz	80 cm / 31.5 in	Yes
Zeta FL (Men's - Women's)	Hiking	N/A	4/10	6/10	4/10	6/10			No	No	No	N20r 2L Gore-Tex	Trim	221 g / 7.8 oz	76 cm / 30 in	Yes
Zeta LT (Men's - Women's)	Hiking	N/A	5/10	7/10	8/10	5/10			No	No	No	N40P-X 3L Gore-Tex	Trim	335 g / 11.8 oz	78 cm / 30.75 in	Yes
Zeta SL (Men's - Women's)	Hiking	N/A	3/10	5/10	4/10	5/10		Review	No	No	No	2L Gore-Tex	Trim	310 g / 10.9 oz	77.8 cm / 30.6 in	Yes

Performance data axis of synthetic jackets (table above) and shell jackets (this table) are different. Don't compare them.

Patagonia and Arc'teryx are like up to 70% off at REI rn...
- https://www.rei.com/h/deals

Most Arc'teryx jackets are equipped with only one insulation density throughout the jacket. It's the same thickness everywhere.

This causes some areas to be over insulated and other areas to be under insulated. Both has their own downsides.

Forget the negative impact that over insulation has on the weight for a second. Because what we're talking about is grams in here.

The primary negative impact of over insulation can mostly be on hindering mobility and comfort. Because some areas, like underarms, do not need that much of insulation.

The primary effect of under insulation is warmth (surprising news). Some areas, like the yoke, can require more insulation. Because it prevents the heat from escaping.

That's why Arc'teryx equips some of their jackets with not one but two different insulation thicknesses. Like the Beta Insulated (Men's - Women's - read my review), Therme (Men's - read my review) and Thorium (Men's - Women's - read my review).

Atom HW is the only Arc'teryx jacket that is equipped with not one, not two, but three different insulation thickness:

120 g/m2 of Coreloft around the yoke, the top of the sleeve, the sides, and the back.
80 g/m2 of Coreloft in the bottom of the sleeves and in the zip guard.
60 g/m2 of Coreloft everywhere else (the front).

This customized insulation distribution makes the Atom Hw more comfortable compared to other jackets with similar warmth.

The Atom is still more comfortable than the Atom Hw, though. Because it's insulated less (60 g/m2 of Coreloft everywhere).

Source of above information:

These are pretty much the biggest differences between the two models. Atom HW is significantly warmer and less comfortable compared to the Atom.

If you're truly active inside the Atom HW, you're likely to overheat. Despite the side fleece panels.

For low output activities; like hiking, mountaineering, or resting between climbing sets; however, Atom Heavyweight would be outstanding, in addition to stationary use (no output).

Poll results: Best colorways of Atom Series

Upvote your favorites.

Atom LT Jacket Men's

Black

Kingfisher

Void

Canvas

Quick links:

https://arcteryx.com/shop/mens/atom-lt-jacket

https://outdoorcrunch.com/arcteryx-proton-lt-vs-atom-lt/

Atom LT Hoody Men's

Void

Canvas

Black

Solace

Heritage

Fika/Black Sapphire

Kingfisher

Quick links:

https://arcteryx.com/shop/mens/atom-lt-hoody

https://outdoorcrunch.com/nano-puff-vs-atom-lt/

Atom SL Hoody Men's

Serene

Black

Canvas

Jungle Maze

Sprint

Solitude

Quick links:

https://arcteryx.com/shop/mens/atom-sl-hoody

https://outdoorcrunch.com/arcteryx-atom-lt-vs-sl/

Atom Hoody Women's

Techno

Atmos

Sprint

Black

Orca

Solace

Fika/Spark

Black Sapphire

Expanse

Velvet Sand

Labyrinth

Quick links:

https://arcteryx.com/shop/womens/atom-hoody

Atom Lightweight Hoody Women's

Wicker/Sprint

Solitude

Groovie

Black

Bliss/Spark

Serene

Quick links:

https://arcteryx.com/shop/womens/atom-lightweight-hoody

Atom Jacket Women's

Black

Solace

Quick links:

https://arcteryx.com/shop/womens/atom-jacket

Atom Heavyweight Hoody Women's

Synth

Habitat

Moonlit

Black

Quick links:

https://arcteryx.com/shop/womens/atom-heavyweight-hoody

Now, although it's quite difficult to pinpoint the warmth differences between these two jackets, let me do my best and at least try to give you an idea:

Warmth

Generally speaking, with only a long sleeved shirt under and without a shell on top, for an average person, during daily use (strolls, power walks, etc) and with enough wind to cause an umbrella to twist in your hand:

...without feeling uncomfortably cold, the lowest temperature to wear an Atom would be 36 deg F (2 deg C), and Atom HW around 18 deg F (-8 deg C).

With at least a moderate quality layering:

...Atom would be at 25 deg F (-4 deg C), and Atom HW at 7 deg F (-14 deg C).

With a good base layer under and a shell jacket on top:

...Atom would be at 10 deg F (-10 deg C), and Atom HW at -4 deg F (-20 deg C).

Links:

Breathability

Atom Hw's small armpit mesh panel.

Atom is the only line in Arc'teryx's entire insulated jacket line-up that offers mechanical ventilation.

In other words, side fleece panels.

However, how these panels are incorporated into these jackets still make them very different than one another.

Look at the side fleece panels of Atom Hw. They only takes place in the armpit area.

They're small and doesn't help that much with ventilation.

Now look at Atom's much larger panels. They span all the way from the armpits to the hem.

Atom's large side fleece panel.

They're spectacular in terms of providing breathability. This single thing gave the Atom the fame it has today.

For reference, Atom SL (soon to be called Atom Lw) has even LARGER panels than the Atom!

It's even more breathable. Check out this Proton vs Atom guide to see its images and read more about it.

Panels this large can be a mixed blessing, though. Which brings me to my next point.

Weather Resistance

Water resistances of these two are top notch. I'm 100% sure they're not going to disappoint. They're coated via DWR, too.

What is DWR by the way?

DWR is a coating.

It's basically sprayed on to the surface of these jackets as a finish.

It stands for Durable Water Repellent - which means that water will be repelled under wet conditions instead of soaking into the fabric.

DWR also decreases dry time.

It's a good thing these jackets are coated in DWR.

But pay attention to the fact that DWR is a coating - meaning that it will wear off over time.

Which is why you might want to invest in a DWR spray such as this one at arcteryx.com for after treatment.

As you see, there's a strong correlation between FP x FW and temperature ratings, but not more than, say, 80%. I explained why this happens here in this post of mine.

When it comes to the wind resistance, however, it's another story. As you can guess by now, Atom Hw is off the charts in this regard too.

But when your arms are up, Atom's side fleece panels invite lots of wind and hence cold in. Even when your arms aren't up, it still does that although not equally as much.

This is something you should to consider.

Abrasion Resistance

The numbers you see in face fabrics indicate the density (in other words the thickness) of face fabric.

So, 30D Tyono face fabric of Atom Hw is stronger than 20D Tyono face fabric of Atom. It better resists against the abrasion when bouldering and backpacking.

Fit

Canberk is 5'11" and 165 pounds, with an athletic build. Size Medium fits him perfectly across almost all brands and product lines.

Arc'teryx's 2024 men's fit revision

Here's what Arc'teryx says about its most recent fit revision:

Source: https://arcteryx.com/us/en/help/sizing/mens/tops/new

Not all jackets come with the revised fit - only the ones with following statement:

Durability

You'd expect the same relationship between them in terms of durability, too. But there's a caveat here.

Larger side fleece panels of the Atom help with stretching more. This puts less stress on stitches over time, and hence can increase the life of jacket.

If you have no plans to use these jackets close to a decade, then you can simply ignore this difference.

The stretchier nature of Atom also makes it more comfortable and allows more mobility. Although I do appreciate the "too small" armpit panels of Atom Hw, they just offer less mobility.

If you need more durability, definitely check out Proton (Men's - Women's - read how it compares to the Atom) and Proton Heavyweight (Men's - Women's - read how it compares to the Atom Hw).

Pockets

Number of pockets are the same. 2 hand warmers and 1 internal zippered chest pocket in each.

Sizes of them are very similar too.

Atom Hw:
- Hand warmers: 9.4 in (or 24 cm) x 6.7 in (or 17 cm)
- Internal zippered chest pocket: 10.6 in (or 27 cm) x 7.5 in (or 19 cm)
Atom:
- Hand warmers: 10.6 in (or 27 cm) height x 7.1 in (or 18 cm) width
- Internal zippered chest pocket: 9.9 in (or 25 cm) height x 7.5 in (or 19 cm) width

Cuffs

Both are pretty elastic.

Left: Atom Heavyweight. Right: Atom.

Conclusion

Atom Heavyweight is a loftier, warmer, more weather resistant and durable version of the Atom. It did not have any alternatives to it for a long time. That's why everyone lost their minds when Arc'teryx shortly "discontinued" it.

Now we have the Proton Heavyweight (Men's - Women's - read how it compares to the Atom Hw), though.

The Atom, on the other hand, is best used for high output activities in general. It's light and comfortable. If climbing is what you're going to do, then I'd mostly recommend the Proton (Men's - Women's - read how it compares to the Atom) instead of this one. It's more abrasion resistant.

Both Atom HW and Atom offer mesh side panels which span all the way from the armpits to the hem. These panels are popular. They make them more breathable than all the other Arc'teryx synthetics.

Keep in mind that overheating inside the Atom HW is easier because it's very warm. That's why people say it's more breathable than the Atom HW.

Lastly, both are fantastic jackets that won't disappoint.

Links:

Arc’teryx Atom AR vs LT

Summary

Warmth

Poll results: Best colorways of Atom Series

Atom LT Jacket Men's

Atom LT Hoody Men's

Atom SL Hoody Men's

Atom Hoody Women's

Atom Lightweight Hoody Women's

Atom Jacket Women's

Atom Heavyweight Hoody Women's

Breathability

Weather Resistance

Abrasion Resistance

Durability

Pockets

Cuffs

Conclusion

NEMO Hornet OSMO Tent Review: Ultralight Performance for 1, 2, and 3 Backpackers

Big Agnes Copper Spur UL2 Tent Review: Ultralight Shelter For Space Seekers

Osprey Aether 55 Review: Field Tested Backpack for Multi-Day Trips