Reversal in wind direction.
The sun causes reversal in wind direction between land and sea.
A sea breeze or onshore breeze is any wind that blows from a large body of water toward or onto a landmass; it develops due to differences in air pressure created by the differing heat capacities of water and dry land. As such, sea breezes are more localised than prevailing winds. Because land absorbs solar radiation far more quickly than water, a sea breeze is a common occurrence along coasts after sunrise. By contrast, a land breeze or offshore breeze is the reverse effect: dry land also cools more quickly than water and, after sunset, a sea breeze dissipates and the wind instead flows from the land towards the sea.
Wikipedia, Sea Breeze, 2019
The sun causes the wind direction to reverse. This was known recently, however this was portrayed in the Quran 1400 years before it was discovered.
[Quran 81:18] And by the morning as it breathes.
"Subh صُّبْحِ" means onset of daylight. When we breath the direction of air reverses. Here the onset of daylight causes the wind direction to reverse. Today we know that the sun causes reversal in wind direction between land and sea.
How could an illiterate man who lived 1400 years ago have known about sea breeze?