The city receives 2,107 hours of sunshine per year, with maximum sunlight exposure occurring in April.[2] Kolkata has been hit by several cyclones; these include systems occurring in 1737 and 1864 that killed thousands.[82][83] More recently, Cyclone Aila in 2009 and Cyclone Amphan in 2020 caused widespread damage to Kolkata by bringing catastrophic winds and torrential rainfall.