I remember that kind of green sky from some Texas tornados...what makes it green?
It’s not just green. I’ve seen it several times, and it’s not like any other cloud. Roiling, boiling, and it looks like an old bruise. Green, but with slight yellowish/purple gray tints.
That sounds ridiulous. You really do have to see it. Just nasty, eerie, and very frightening.
According to meteorologist Craig Bohren,
http://ploneprod.met.psu.edu/news-events/events/meteo-colloquia/2012/craig-bohren
..."green thunderstorms are caused when afternoon light, already depleted in blue wavelengths by traversing a long path through the atmosphere, passes through storm clouds that absorb much of the longer-wavelength colors (reds and yellows). What remains is a green light that actually emanates from the cloud base...
"...When a significant fraction of the longer wavelength is filtered out by the cloud water, green is the predominant color of the light that remains. Of course, a lot of water is required to do this kind of filtering."
(from the Weatherwise 2001 article)