I go out both long and short duration and always dress light and find
that all my warmth is generated just by steady activity. Thin outfits
also wick quick and stay dry. If I stop for more than, like, 2
minutes, I'll pop on a shell vest to cut any breeze.

But I go WOOL AND ALL WOOL AND NOTHING BUT WOOL.

It breathes. It protects from wind.

I suppose I mostly do semi-sheltered skiing, with trees around.

But my 90% outfit is thin wool tee or longsleeve or tneck with a
Woolrich shirt on top -- shirt can range from thin to thick.

If it's 10F in a.m., warming to 20 in p.m., I'll start and stick with
wool longsleeve plus medium-weight Woolrich button-up shirt.

If it's -5F warming to 10F I'll use thin tneck with thicker shirt.

2 thin socks do the trick.

If I'm moving I find even wet feet stay warm. -- We skied our last day
for 7 hours with drenched feet, no prob.

Med-lite XC gloves. When I first start skiing the hands will go thru
about 3 cycles of different kinds of pain if it's 0F lasting 15
minutes total before they settle in on being warm. It's interesting.

....But everyone is different!

(If I tried skiing even a half hour with thicker stuff for a given
temp I would sweat it drenched and be miserable. My skiing and
thinking ability -- and enjoyment -- plummets when I overheat. And I
can't ski AT ALL with nylon coated windblocking fabrics. Not even for
a "warmup." They stifle me promptly.)

--JP outyourbackdoor.com