Weather sealing is an over rated feature. The Canon M3 is not weather sealed. I’ve shot my M3 in the rain and snow of Yosemite and Monument Valley and haven’t had a problem. Just don’t change lenses if it’s dusty or windy! The main problem is keeping rain drops and snow flakes off of the lens. Keep a dust cloth handy for this. Still, if it’s raining and snowing hard, it’s difficult. An umbrella and assistant can come in handy. Note that the M5 viewfinder eye sensor is really sensitive and if a rain drop gets on it the LCD will black out. This was a problem since I use the LCD exclusively now and when it rains the M5 will black out the LCD. There may be a workaround, but I didn’t find it.
Shooting in Yosemite Valley March 5, 2017. It was snowing and in the 30’s F but the M3 had no problem. Use the remote release so you don’t have to touch the camera.
Shooting in the rain and below freezing temps. I just threw a pair of Nike Dry Fit shorts over the camera waiting for the weather to clear and the light to get better. A few minutes later the temps dropped even more and it started to snow. The monuments were obscured.
The bottom line is that a weather sealed body is not really needed for outdoor photography in the rain and snow. For dusty and sandy environments like Antelope Canyon or Death Valley the M3 also did fine. However, bring Ziplock bags in your bag if going to sandy areas. You may encounter a sandstorm and need to zip everything up quickly.
Canon M Cameras 