word | | Climate |
| May | France | ... June to October); vulnerable to devastating cyclones (hurricanes) every eight years on average Reunion: tropical, but temperature moderates with elevation; cool and dry (May to November), hot and rainy (November to April |
| May | Gambia, The | tropical; hot, rainy season (June to November); cooler, dry season (November to May) |
| May | Guinea | generally hot and humid; monsoonal-type rainy season (June to November) with southwesterly winds; dry season (December to May) with northeasterly harmattan winds |
| May | Guinea-Bissau | tropical; generally hot and humid; monsoonal-type rainy season (June to November) with southwesterly winds; dry season (December to May) with northeasterly harmattan winds |
| May | Guyana | tropical; hot, humid, moderated by northeast trade winds; two rainy seasons (May to August, November to January) |
| May | Holy See (Vatican City) | temperate; mild, rainy winters (September to May) with hot, dry summers (May to September) |
| May | Indian Ocean | northeast monsoon (December to April), southwest monsoon (June to October); tropical cyclones occur during May/June and October/November in the northern Indian Ocean and January/February in the southern Indian Ocean |
| May | Laos | tropical monsoon; rainy season (May to November); dry season (December to April) |
| May | Malawi | sub-tropical; rainy season (November to May); dry season (May to November) |
| May | Marshall Islands | tropical; hot and humid; wet season May to November; islands border typhoon belt |
| May | Mauritius | tropical, modified by southeast trade winds; warm, dry winter (May to November); hot, wet, humid summer (November to May) |
| May | Mayotte | tropical; marine; hot, humid, rainy season during northeastern monsoon (November to May); dry season is cooler (May to November) |
| May | Oman | dry desert; hot, humid along coast; hot, dry interior; strong southwest summer monsoon (May to September) in far south |
| May | Pacific Ocean | ... a dry season during the winter months, when dry winds blow from the Asian landmass back to the ocean; tropical cyclones (typhoons) may strike southeast and east Asia from May to December |
| May | Palau | Tropical; hot and humid; wet season May to November |
| May | Panama | tropical maritime; hot, humid, cloudy; prolonged rainy season (May to January), short dry season (January to May) |
| May | Papua New Guinea | tropical; northwest monsoon (December to March), southeast monsoon (May to October); slight seasonal temperature variation |
| May | Philippines | tropical marine; northeast monsoon (November to April); southwest monsoon (May to October) |
| May | Saint Kitts and Nevis | tropical, tempered by constant sea breezes; little seasonal temperature variation; rainy season (May to November) |
| May | Saint Lucia | tropical, moderated by northeast trade winds; dry season January to April, rainy season May to August |
| May | Saint Vincent and the Grenadines | tropical; little seasonal temperature variation; rainy season (May to November) |
| May | Samoa | tropical; rainy season (November to April), dry season (May to October) |
| May | Sao Tome and Principe | tropical; hot, humid; one rainy season (October to May) |
| May | Senegal | tropical; hot, humid; rainy season (May to November) has strong southeast winds; dry season (December to April) dominated by hot, dry, harmattan wind |
| May | Seychelles | tropical marine; humid; cooler season during southeast monsoon (late May to September); warmer season during northwest monsoon (March to May) |
| May | Sierra Leone | tropical; hot, humid; summer rainy season (May to December); winter dry season (December to April) |