Are Japanese schoolgirls hardier than their US counterparts?

If a young lady from the US ended up in a Japanese school by way of her parents being in country for a time, would she be able to endure as the Japanese schoolgirls do in respect to the cold and wearing their uniform? The fact that more than a few Japanese schoolgirls wear their skirts short in rain, wind, and cold weather cold weather (that even includes snow) are they hardier than there US sister students who seem to be debilitated if they have to venture into 65 deg. weather in a regular skirt? What make schoolgirls in Japan better able to handle the cold than female students here, even in the east or up in northern states where it snows?