July is peak summer in California with average high temperatures between 80°F (26.7°C) to 85°F (29.4°C). The northern parts and highlands, coastal areas, and central regions are a little cooler compared to the eastern and southern parts that border the states of Nevada and Arizona, which have a semi-arid climate. The desert areas regularly cross 110°F (43.3°C) during the days, while the nights see a difference of 30°F (-1.1°C) in temperature. It is an excellent time to hike the mountains whose high altitude passes are impassable during the winter due to snow. Rain and humidity drop substantially during the summer and makes way for mostly clear skies. Summer sees peak crowds in the Yosemite National Park area - be sure to get weather updates regarding wildfires and flash floods! Take precautions against the ultraviolet rays of the sun, particularly on the beaches where people prefer light clothing. Overall, California summers are mostly temperate compared to those of the neighboring states of Nevada and Arizona.