According to the Köppen climate classification system, Mount Harrington is located in an alpine climate zone. Most weather fronts originate in the Pacific Ocean, and travel east toward the Sierra Nevada mountains. As fronts approach, they are forced upward by the peaks, causing them to drop their moisture in the form of rain or snowfall onto the range (orographic lift). Precipitation runoff from this mountain drains into tributaries of the Kings River.
^R. J. Secor, The High Sierra Peaks, Passes, Trails, 2009, Third Edition, Mountaineers Books, ISBN9781594857386.
^Peel, M. C.; Finlayson, B. L.; McMahon, T. A. (2007). "Updated world map of the Köppen−Geiger climate classification". Hydrol. Earth Syst. Sci. 11. ISSN1027-5606.