It's tempting to think no vents means more warmth, but helmets without ventilation are extremely rare and really only designed for extreme cold-weather racing. For most skiers, even those who run cold, a helmet with no ventilation creates more problems than it solves.
The big issue is that without any airflow, heat and moisture get trapped inside. You might stay warm at first, but as you sweat, that moisture has nowhere to go. This leads to a damp, chilly liner and — worse — fogged goggles that are nearly impossible to clear on the hill.
A better approach is to choose a helmet with adjustable vents. You can keep them closed on cold lift rides or windy peaks, then crack them open when you're working hard or the sun comes out. This gives you warmth when you need it and airflow when you don't, without the fogging and overheating issues of a non-vented helmet.