According to the
Köppen climate classification system, Monrovia Peak is located in a
continental climate zone (Dsa) with mostly dry summers (except for scattered summer thunderstorms) and cold, wet winters. Most weather fronts originating in the Pacific Ocean travel east toward the San Gabriel Mountains. As fronts approach, they are forced upward by the peaks (
orographic lift), causing them to drop their moisture onto the range. Precipitation runoff from this mountain drains into the
San Gabriel River watershed. ==See also==