I've had 3 shed roofs fall because of snow,so far no house roofs!
To inspect an asphalt roof without getting up on a ladder, use binoculars. Walk around the house at ground level , repeating the process at different times of the day so that you check things out under all kinds of light conditions. If you have friendly neighbors that have a second floor window or deck that has a better view-point ask if you can check out your roof from their room upstairs. Be especially sure to check the south facing side of the building. This is the area that usually gets the most exposure to the sun's ultraviolet light, so it tends to have the shortest life span.