Our eastern horizon is the composed of the alpine peaks that surround Yosemite Valley, and in the twilight picture above, one can see the snowy peaks of the high country. The snow is a welcome sight, but it is still too little to put a dent in the second year of drought conditions.
The Worm Moon refers to the thawing of the soil, allowing worms to start doing what worms do. We don't see much of a difference here in the warm climes of California, but the worms are certainly active in the garden right now.
This moon is also a "super-moon", meaning the moon is relatively closer to the Earth in this part of its orbit, so it appears a bit larger and brighter than "normal". There will be four "super-moons" this year.