Tropical climate The Cape York region is situated at the northern tip of Queensland in a tropical climatic zone where summers are wet and winters are comparatively dry (Bureau of Meteorology 1989). Coastal climatic effects are pronounced in this region as it is bordered by the Gulf of Carpentaria to the west and the Coral Sea to the east.Average temperatureSummers are hot with maximum temperatures around 33-36ºC in January. The coolest temperatures are experienced along the coast and to the east (Colls & Whitaker 1990). Humidity is high, averaging 60-80 per cent, across the region with southern inland readings lowest. Climate discomfort days range from only 50 along the north and east coasts to 150 in the south-west (Bureau of Meteorology 1989) in close association with temperature gradients. Even though this region averages seven to eight hours' sunshine each day, it is one of the cloudiest in the savannas (Colls & Whitaker 1990).RainfallNorth-west monsoons bring heavy summer rains which in combination with the moist south-easterly trade winds combine to shed an annual average of 800 mm in the south to a prolific 2400 mm in the north. In inland regions more than 90 per cent of this rain falls in summer whereas only around 75 per cent falls as summer rain along the coast. There is only low to moderate variability in this rainfall (Bureau of Meteorology 1989) with droughts less likely to occur in the north (Colls & Whitaker 1990).Tropical cyclones are associated with the most widespread, heavy rainfalls followed by thunderstorms and monsoon depressions (Gentilli 1972). Thunderstorms occur less frequently here than in other regions with an annual average of as few as 20 thunder days along the coast to perhaps twice that many inland (Bureau of Meteorology 1989). In La Nina years rainfall increases across the entire region in an east-west direction (Partridge 1991).WinterAfter the summer rains ease and the south-east trade winds become established relative humidity can fall to 30 per cent by July but in some areas along the eastern coast it may linger around 80 per cent (Colls & Whitaker 1990). Winter rainfall can be associated with the moist trade winds being uplifted over the coast. Temperatures moderate in winter with July average minimums dropping to 21ºC in the north and 15ºC in the southern inland areas (Colls & Whitaker 1990).