Hi Rose,
taking photographs of snow can be a very tricky scenario. Try to avoid allowing the camera to do all of the work as all of the bright highlights in the scene often confuses the sensors and leaves you with an over-exposed image as seen here, note the loss of detail in the white of the snow. (Snow is not white, this is just the reflective light from the suface of the frozen water droplets). There are several options in these circumstances, 1. A grey card. This is a card which can be purchased from many good photography shops which will give you an accurate average light reading in just about all bright conditions. Simply fill the frame with this card from around 3 - 4 feet and note the reading from there. Override the camera settings with that reading and this should give you better exposure results. If you do not have a grey card try to find a similar subject to take a reading. Here I would have used the shadow side of the boulder. 2. Try bracketing your shots. Takes several shots and alter the shutter speed or aperture to allow several different exposures, with digital you have nothing to lose execpt the photo itself if you don't. 3. Don't give up.
Great shot and Good luck.
Regards.....Phil

__________________
Regards....Phil

If it moves shoot it. If it doesn't move, still shoot it.