Culiacán haes a semi-arid climate (Köppen: BSh), despite receivin a annual rainfaw o ower 600 millimetres (24 in), due tae its het temperaturs an heich evaporation. Simmers are vera het an humid, shade temperaturs can reach 45 °C (113 °F) an heich humidy can produce heat indexes o 50 tae 55 °C (122 tae 131 °F), wi the risk o hivy rainfaw frae decayin tropical cyclones present an aw. Winters are hintle milder wi less humidity an a average heich o 27 °C, wi ceul nichts.