Funny you should happen to mention *psoriasis; I'VE suffered from this unsightly skin condition for at least 35 years ... mainly on my shins and elbows ... and, although widely BELIEVED to be stress-related, I DO think there's a corelation between *it and the weather. On each of the two occasions I was in the Philippines, for instance, the flaky, whitish-silver patchy "scales" associated with the condition seemed to all but vanish ... probably due to the dermatalogical effects of the sun's ultra-violet rays on the uncovered skin's surface.