Temperatures can range from as low as freezing in January and February to 48 °C in July and August. Rain falls mostly between June and September, with annual precipitation between 75 and 300 millimeters. Most of the vegetation here consists of mesquite trees as well as trees such as the desert ironwood, palo verde and the huisache. Desert animals such as the desert tortoise, rattlesnakes, bighorn sheep and lynx are the most notable species. Populations of feral Red-Masked Parakeets are a local sightseeing event here.
Hermosillo's all-time weather records for high temperature is 48 °C, which was achieved in 1998, and since then, few other times throughout the 2000s and back again in the 2010s. In the recent years, the lowest temperature was -3 °C, in January.
