Weather in Jamaica All countries Weather in Jamaica Weather in Jamaica by months: JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember Weather by city City Now Sea water Rain Wind Boston Bay Beach +28°C +30°CBoston Beach 20% 4 m/s Cornwall Beach +28°C +29°CCornwall Beach 25% 3 m/s