| Country | Climate |
| Tanzania | varies from tropical along coast to temperate in highlands |
| Thailand | tropical; rainy, warm, cloudy southwest monsoon (mid-May to September); dry, cool northeast monsoon (November to mid-March); southern isthmus always hot and humid |
| Timor-Leste | tropical; hot, humid; distinct rainy and dry seasons |
| Togo | tropical; hot, humid in south; semiarid in north |
| Tokelau | tropical; moderated by trade winds (April to November) |
| Tonga | tropical; modified by trade winds; warm season (December to May), cool season (May to December) |
| Trinidad and Tobago | tropical; rainy season (June to December) |
| Tunisia | temperate in north with mild, rainy winters and hot, dry summers; desert in south |
| Turkey | temperate; hot, dry summers with mild, wet winters; harsher in interior |
| Turkmenistan | subtropical desert |
| Turks and Caicos Islands | tropical; marine; moderated by trade winds; sunny and relatively dry |
| Tuvalu | tropical; moderated by easterly trade winds (March to November); westerly gales and heavy rain (November to March) |
| Uganda | tropical; generally rainy with two dry seasons (December to February, June to August); semiarid in northeast |
| Ukraine | temperate continental; Mediterranean only on the southern Crimean coast; precipitation disproportionately distributed, highest in west and north, lesser in east and southeast; winters vary from cool along the Black Sea to cold farther inland; summers are warm across the greater part of the country, hot in the south |
| United Arab Emirates | desert; cooler in eastern mountains |
| United Kingdom | temperate; moderated by prevailing southwest winds over the North Atlantic Current; more than one-half of the days are overcast |
| United States | mostly temperate, but tropical in Hawaii and Florida, arctic in Alaska, semiarid in the great plains west of the Mississippi River, and arid in the Great Basin of the southwest; low winter temperatures in the northwest are ameliorated occasionally in January and February by warm chinook winds from the eastern slopes of the Rocky Mountains |