Mobile has a subtropical climate — hot and humid in summer, mild in winter. The best time to visit is from February through April, when temperatures are comfortable and the city is at its most festive. Mardi Gras season (January through Fat Tuesday) is the peak event and fills hotels fast; book well ahead if you want to see the parades.
Summer (June-August) is hot and oppressively humid, and the city occasionally takes direct hits from Gulf hurricanes. Winter is mild by most standards — temperatures rarely drop below freezing — but December and January can be grey and rainy. Spring and autumn offer the most pleasant weather.