A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z
| Location | Type | Continent | Website |
| Oahu - Hawaii | Islands | North America | weatheroahu.com |
| Oceania | Continent | Australia and Oceania | weatheroceania.com |
| Ohio - USA | Area | North America | weather-ohio.com |
| Oklahoma - USA | Area | North America | weather-oklahoma.com |
| Omaha - Nebraska | City | North America | omaha.weather-nebraska.com |
| Oman | Country | Asia | weatheroman.com |
| Oranjestad - Aruba | City | North America | weatheroranjestad.com |
| Oranjestad - Saint Eustatius | City | North America | sinteustatius.weatheroranjestad.com |
| Oregon - USA | Area | North America | weather-oregon.com |
| Orkney Islands - Scotland | Islands | Europe | orkneyislands.weather-scotland.com |
| Osaka - Japan | City | Asia | weatherosaka.com |
| Oslo - Minnesota | City | North America | minnesota.weatheroslo.com |
| Oslo - Norway | City | Europe | weatheroslo.com |
| Ostend - Belgium | City | Europe | ostend.weatherbelgium.com |
| Ottawa - Canada | City | North America | weather-ottawa.com |
| Ouagadougou - Burkina Faso | City | Africa | weatherouagadougou.com |
