The Sinharaja rain forest cover receives between 3000-6000 mm of rain throughout the year and have a minimum rainfall of over 200 mm even during non monsoon periods. The mean temperature is between 18-27 degrees Celsius with a humidity of 75% - 90%. Only a faint sunshine reaches the ground layer of the forest which ranges from 5% - 15% of the total sun light. The land coverage of the Sinharaja Forest is 21 kM lengthwise, with a minimum width of 3 kM and a maximum width of 7 kM throughout that land extent.