The Mayan Highlands are located on the southern portions of Mexico and most of Guatemala. The name "Highlands" comes from the surrounding landscape which consists of the Sierra Madre Mountains. These mountains range from east to west, dividing the landscape. The surface of the Highlands is just as diverse as that of the Lowlands, ranging from grasslands, to tropical rainforest, to mountains. Most of the mountains are volcanic, so only the land in the mountain valleys is able to produce food.
The climate of the Highlands is generally the same as the Lowlands, except on the mountain tops. The temperature averages between 83 degrees and 68 degrees in the mountain areas. Altitude plays a large factor in the temperature. The annual rainfall in the Highlands also varies with the altitude. In the northern area of the Highlands, rainfall averages from 60 to 100 inches per year, while in the southern areas, rainfall only averages about 52 inches per year. This large decrease is due to the rising elevation along the mountains.
Most of the vegetation of the Mayan Highlands consists of large hardwood trees, such as oak and pine. These trees typically grow 7000 feet above sea level. Orchids and many other flowers also grow in all parts of the highlands.
Deer, monkeys, and peccaries are commonly found, especially in the mountain valleys. On the slopes and higher elevations of the Highlands, jaguars, tapirs, and puma can usually be found.
References:
http://udgftp.cencar.udg.mx/ingles/
Precolombina/Maya/temp19.html
http://udgftp.cencar.udg.mx/ingles/
Precolombina/Maya/temp20.html
Microsoft Encatra '96 Encyclopedia
Maya Ruins in Central America in Color, by William M. Ferguson and John Q. Royce, 1986.
Late Lowland Maya Civilization, School of American Research Advanced Seminar Series, Edited by Jeremy A Sabloff and E. Wyllys Andrews V, 1986.