However be careful in the Sun even if it is good for you still use Sun Cream to protect your skin. But climate can affect some people's psoriasis and only trial and error will each person know how it affects them.

I have pustular psoriasis & ive gone gluten free, dairy free except eggs! Dairy in an inflammatory so worse thing for skin! I made a mix of organic coconut oil in a salsa jar with 10 drops of 100% geranium oil & it's almost gone after being severe on soles of feet for 12mths!! Worth a try!

Yes winter is worse

The foot issues can go along with the Arthritis. I am off to see a podiatrist in Oct. I always suggest people get good walking shoes.
The weather has an effect for sure. Winter Cold I find isn't really the issue for me. The dry weather that comes with MN cold cuases the skin to flare which cuases the Arthritis to flare. I keep a humidifier running all winter long. I try to keep my skin moisturized and even though I love hot showers I try not to do that. Weather changes especially High Pressure is a problem. It's been a stormy summer and one of the worst summers I have had in years. I try and keep stress low and even in the winter I go outside to get sun. Vitamin D is crucial. I would encourage people to keep getting that checked in the winter especially if you stay inside a lot. I also use an incumbent bike on the winter months to keep my muscles going. I set in front of the TV. I am trying to more storm mindful. If there high pressure coming in I try and adjust my activity.
Peace and Blessings