Red sky at morning – Wikipedia

If the morning skies are of an orange-red glow, it signifies a high-pressure air mass with stable air-trapping particles, like dust, which scatters the sun’s blue light. This high pressure is moving towards the east, and a low-pressure system moves in from the west. Conversely, in order to see “red sky” in the evening, high-pressure air mass …

https://en.wikipedia.org/wiki/Red_sky_at_morning