At the top of the Sierra Nevada in Spring the snow melts and lots of small streams and rivers form. In Spanish rivers and stream are called "arroyos" or "riochuelos" you will see these words on maps. At the side of the rivers are large green carpets of vegetation. If you go hiking it can be very pleasant to eat your packed lunch at the side of one of these streams. The sun is normally blue, there are often large eagles floating in the sky, but as it is so high it still may be cold even in May or June.