Vernal Fall is so named because of the cool, vernal spray in contrast at midday with summer heat, reminding me of an April shower, and because of the blue grass curiously growing among dark rocks and gay, dripping flowers, making it an eternal April to the ground. -- Lafayette Bunnell, 1851.
Vernal Fall is 317ft high and 80-100 feet wide at it's Spring peak. Because the Merced River drains the large absorbent Tuolumne Meadows above, the Falls remain active throughout the dry summer months. This is Yosemites 12 highest waterfall.