What does a sky redish with grey clouds mean when it occurs during spring, not summer?

Answer 1

remember color is caused by reflection/refraction of light.
so the color could have come from suspended dust/pollution.
also, sometimes the sky will be reddish before a strong front. there is an old mariner's tale to predict the weather that says "red sky at night - sailor's delight. red sky in morning, sailor take warning." I live on coast and only have found it to be true 1/2 the time. maybe it works differently in open sea. I have also seen blood red skies after a front passes or sometimes in association with severe weather like tornado weather.

Answer 2

In Wales, it means that the locals have burned down another Englishman's holiday home