Many years ago I read that it was better to take outdoor photos on a cloudy day, rather than a sunny one. The less intense light allowed the colors to be more true and less washed out. It had never occurred to me and seemed counterintuitive, until I actually tried it. The colors really were more vibrant. Since then, I've tried to get garden photos on cloudy days and just this spring found how beautiful things can be after it rains.
It's true everyone loves a sunny day and after a week of rain our moods certainly do suffer. It's good to be reminded that even rainy days are good for something, even if it's just getting a few photos to be looked at on another, brilliantly bright day.