Despite its small size, Maryland exhibits considerable climatic diversity. Temperatures vary from an annual average of 48°F (9°C) in the extreme western uplands to 59°F (15°C) in the southeast, where the climate is moderated by the Chesapeake Bay and the Atlantic Ocean. The daily mean temperature for Baltimore is 55°F (13°C), ranging from 33°F (1°C) in January to 77°F (25°C) in July. The record high temperature for the state is 109°F (43°C), set on 10 July 1936 in Cumberland and Frederick counties; the record low, –40°F (–40°C), occurred on 13 January 1912 at Oakland in Garrett County.
Precipitation averages about 49 in (124 cm) annually in the southeast, but only 36 in (91 cm) in the Cumberland area west of the Appalachians; Baltimore averaged 41.9 in (106 cm) annually 1971–2000. As much as 100 in (254 cm) of snow falls in western Garrett County, while 8–10 in (20–25 cm) is average for the Eastern Shore; and Baltimore receives about 22 in (56 cm).