The NPS put out a warning today and I think Edie will attest to this fact based on her recent first hand knowledge:
NPS: Additional snow will result in additional tree failures, sometimes in developed areas. Please be aware of your surroundings during and after winter storms. Parking under that big tree may mean less window scraping–and it may mean your car gets smashed!
People have been killed during tree failures both inside building and out so don’t think you’re safe if you’re in a cabin. Yosemite is notorious for “microbursts” which can cause trees to be sheared off or even ripped out of the ground. If you see an area blocked off please stay out. You wouldn’t want to be another casualty. For more information please check out the NPS Tree Hazards web page.