The skies should remain mostly sunny Friday with a few clouds popping up in the afternoon through the weekend. Those clouds are unlikely to produce any thunderstorms on Saturday, and only isolated storms are possible Sunday through the middle of the next work week. Temperatures will rise to the mid-90s Friday and will top out near 100 degrees through the weekend.

Sunrise Nevada

If you are a sun-watcher, you may have asked the same question as Ted: “What is the actual definition of sunrise and sunset for astronomical/weather purposes? Is it the exact time the sun appears or disappears over the mountains or the time it would appear or disappear if our location was on a flat plane, i.e., the middle of the Pacific Ocean?”

Sunrise water

Sunrise occurs at the moment top of the sun appears (or would appear) on a theoretical flat horizon, such as you would get if the sun rose over the ocean and you were standing on the shore. Sunset occurs when the last of the sun disappears over that same flat horizon. That means if the horizon isn’t actually flat, sunrise will occur sooner than you actually can see the sun, and the sun will disappear (behind mountains, etc.) prior to the official sunset.

Sunrise diagram

Advertisements