White patches on spaghetti squash

Been getting this white patches on the leaves that almost look like a mold or something fuzzy. And then the edges of the leaves are yellowing. This is the center of the plant and the oldest leaves however. Water once a day. We had a night touch below 50 last week. I water once in the morning. Located in western Washington Tacoma-ish. Open to all advice. First time veggie gardener