Tropical cyclones may occur, particularly between mid-December and mid-March. See Natural Disasters
New Caledonia is a French Overseas Territory. There is no formal British diplomatic representation. If you need consular assistance, contact the British Embassy, Paris.
There is a low threat from terrorism. See Terrorism
Most visits to New Caledonia are trouble free. Crime levels are low but you should take normal precautions.
Take out comprehensive travel and medical insurance before you travel.