Climate in Los Mochis is semi-arid wet and dry (BSh), bordering on arid (BWh). Summers are extremely hot, reaching 40 �C (104 �F)and overnight lows of 26 �C (79 �F) with very high humidity making the night extremely hot and heat indices may reach 45 �C (113 �F)in the day. Winters are very warm, reaching 30 �C (86 �F) in the day, even though the lowest temperature recorded was 2.5 �C (36 �F)during January 1971. Rainfall concentrates in the summer: it is common to see thunderstorms and even occasionally hurricanes in August and September, but winters are dry with almost no rainfall, though on 29 December 1978 133.4 millimetres (5.25 in) fell. The highest daily rainfall, however, was from a hurricane on 8 October 1985 and to talled 211 millimetres (8.31 in)
