Elevation and its effects

 

The areas described on this site are mostly between eight and just over ten thousand feet in elevation, depending on just where you are.  .

 

A good rule of thumb is that the average temperature decreases about 3 degrees for every thousand feet of elevation gain, so a little quick math will tell you that the average will be from 24 to 30 degrees cooler than they are in the Central Valley.

 

Remember, those are average temperatures.  There are times, particularly on sunny winter days, when the temperature at high elevation is actually warmer than it is in the foggy valley.  Other times, therefore, the differential is a lot greater, sometimes 50 degrees or more.  The climate at high elevation is drastically different from what is found lower down.  Weather reports are often inaccurate, or describe the “High Sierra weather” as what is likely to be experienced in Yosemite Valley, elevation 4,000 feet.  Those reports aren’t going to resemble what will be found at 9,000 feet. 

 

An observant reader may have noticed that poison oak was not mentioned on this site.  That is because that noxious weed does not grow much above 4,500 feet or so.  Any shrub you see in the areas described here will not be poison oak.  Rattlesnakes, as mentioned elsewhere, are very rare at these elevations, another boon to high country hikers.  They are, however, very common to the lower elevations in the Sierra.

 

The air a mile and a half or two miles above sea level is a lot thinner than it is lower down.  Hikers not accustomed to the elevation may find themselves out of breath while climbing or walking fast.  See also the precautions about altitude sickness in the “dangers” section.

 

Powerful thunderstorms sometimes pummel the high elevations described here. Small step across streams can become very dangerous. Lightning can strike, particularly on high ridges. Hail and high winds are common during those storms. The hiker needs to be prepared for weather, and may have difficulty finding safe stream crossings.

 

There is a lot less air between you and outer space here, so, despite the cooler temperatures, the sun is far more intense than it is lower down.