Poland has a continental climate, conditioned especially by westerly winds. Only the southern areas are humid. Summers are cool, and winters range from moderately cold to cold. The average mean temperature is about 7° C (45° F ); temperatures in Warsaw range, on average, from –6° to –1° C (21–30° F ) in January and from 13° to 24° C (55–75° F ) in July. Precipitation is greatest during the summer months, lasting 85 to 100 days. Annual rainfall ranges from about 50 cm (20 in) in the lowlands and 135 cm (53 in) in the mountains; the overall average is about 64 cm (25 in).