"What is blue? the sky is blue
Where the clouds float thro'"
---- Christina Georgina Rossetti
Code Source: https://github.com/YuqiaoQin/MyWeather
When you look up, it has the purest blue...
Lord Rayleigh illustrate that the shorter the wavelength, the more it’s scattered. And the more its scattered, the more it reaches our eyes from different directions, dictating what colour we perceive the sky to be.
What makes the sky has different blue in different temperature?
The Rayleigh scattering directs more blue light towards your eyes while the indirect sunlight decreases the incoming levels of red and green. When it turns cold, in the northeast the sun begins to sink lower and lower in the sky as we move toward colder, this is true for anyone living in a temperate zone (between 30 and 60 degrees latitude N and S), so the sky does appear bluer.
Also, humidity define the blue level.Warm air, on average, can hold more moisture while cold air can hold less. Winter air tends to be less humid and therefore tends to be less hazy than summer air.
When the weather is cold, the sky more likes...
When the weather is hot, the sky more likes...
Base on this, I pick up a series of blue and map them into different temperature, with milk blue goes hot and dark blue goes cold.
When the weather turns rainy, the sky colour will become more grey. When you zoom to 5, you can see the rainy area with grey dot shining on map.