Why is it cold here???   I decided to look up the definition(s) of High Desert on Wickopedia:

High desert

From Wikipedia, the free encyclopedia

High desert refers to inland high-elevation (commonly 2000 feet [610m] or more above sea level) deserts of the American West, the Middle East, and other parts of the world. Examples of high deserts in North America include the Great Basin Desert and the Mojave Desert.

Places[edit]

• High Desert, Albuquerque, New Mexico, a development in Albuquerque, New Mexico, United States
• High Desert (California), an area encompassing north Los Angeles County, north San Bernardino County, and Kern County, California, in the United States
• High Desert (Oregon), an area in Eastern Oregon, United States
• Colorado Plateau, a high desert area in the United States of 337,000 km2 (130,000 mi2) within western Colorado, northwestern New Mexico, southern and eastern Utah, and northern Arizona.

Other[edit]

• The High Desert Museum in Bend, Oregon, United States
• High Desert State Prison (Nevada) in Indian Springs, Nevada
• High Desert State Prison (California) in Susanville, California

Here's what I find about the elevation of the El Mirage Dry Lake:

El Mirage Lake

El Mirage Lake is a dry lake bed in the Mojave Desert of San Bernardino County, California. The lake is located about 9 miles west-northwest of the town of Adelanto and 10 mi north of Highway 18 in San Bernardino County. Wikipedia

Surface elevation: 2,838' (865 m)

Length: 6.214 miles (10 km)

Width: 1.864 miles (3 km)

El Mirage Lakebed experiences a desert climate, with cool winters and hot summers. Due to the lakebed's aridity and altitude, theDiurnal temperature variation is substantial. Though summer days can be very hot, summer nighttime temperatures are cool. The lakebed receives an occasional dusting of snow in the winter months, however, snowfall usually melts within 24 hours.