I purchased them two years ago and I tried to display them outside and I did have a problem with them blowing over. They are made of foam so they are not very heavy. They also turn color if left out in the rain...but I think it just gives them an even more authentic look. I finally decided just to keep them indoors for our Halloween party and they look amazing.

The 5' mummy's shipping weight (according to UPS) is 10.7 pounds and the 6' has a shipping weight of 13.4 pounds. I would say the box itself weighed 3-4 pounds (?) so they're pretty light. I'm not going to have mine outside, but I'm sure they would easily fall over in windy weather. You may be able to weight down the platforms that they're feet are on, but then I'd worry about the top being blown off and damaging the attachment.

I'm not sure how much they weight. They are not very heavy. I do live in a windy area, at one point the wind knocked the smaller one down. I had to reposition them to an area that was not affected by the wind and they held up just fine throughout our Halloween party.

I put each of them on the scale. 5' weighed about 5 pounds, and the 6' weighed about 7 pounds. There is a looped cord in the back of each one, so you can attach it to a hook on the wall behind them. I have mine in the living room next to front door, but I think they'd work fine on a covered porch if you tie them down.

Extremely LIGHT WEIGHT but they have a cord in the back which can be used to tie them down.

These mummies are not very heavy - I would guess 10-15lbs at the most. They are styrofoam wrapped with guauze. They are on a sturdy base and seem pretty sturdu. They also have a long jute loop (string) in their back that you could use to secure them to keep from blowing over.
I wouldn't recommend to use them outside in inclimate weather - I don't think they would fare well in the rain.