Red sky at night, sailors delight. Red sky in the morning, sailors take warning.
The saying “red sky at night…” is typically true if you’re in North America.
In the mid-latitudes, weather systems travel west to east and the sun rises in the east and sets in the west.
So a sun rising before any approaching weather system will illuminate the approaching mid- and high-level clouds to create a red sky in the morning.
If the sun is setting as a weather system is leaving and high pressure is building, then the departing clouds would be lit.
This would create a red sky at night with decent weather to follow.