OpenUV is described as 'The missing global real-time UV index API for awesome developers, innovators and smart home enthusiasts that you've been looking for' and is a Weather Forecast Tool in the Online Services category. There are more than 50 alternatives to OpenUV, not only websites but also apps for a variety of platforms, including iPhone, Android, iPad and Android Tablet. The best alternative is Geometric Weather, which is both free and Open Source. Other great sites and apps similar to OpenUV are Forecastie (Free, Open Source), The Weather Channel (Freemium), AccuWeather (Freemium) and Clima (Free, Open Source).
Snowflake is an incredibly detailed weather app, covering almost everything you could possibly want to know about current conditions and forecasts. Snowflake is privacy focused, with no ads, no analytics, and no creepy tracking.