why does it get colder when the sun comes up
When the sun comes up, it can briefly keep getting colder because the ground and air are still losing more heat than they’re gaining from that low, weak sunlight.
Key idea in one line
Temperature usually bottoms out around or just after sunrise because Earth has been cooling all night and the first rays of sun are too angled and weak to reverse that immediately.
What’s actually happening
- All night long, the ground and the air near it radiate heat out to space, like a warm object slowly cooling in a dark room.
- As long as that heat loss is greater than the tiny bit of energy arriving from the sun (which is zero at night and still very low at first light), the temperature keeps dropping.
- Right at sunrise, the sun is very low on the horizon, so its light is spread over a large area and weakened by the atmosphere; the energy per square meter is still small.
So for a short time after the sun appears, the balance is still “more heat leaving than coming in,” and the air can dip to its lowest temperature of the day.
Why it can feel colder when the sun appears
- Near the ground, a very thin layer of air can be colder than the air at eye level, especially on clear, calm nights.
- When the sun comes up, it starts to warm the ground, stirring the air and mixing that colder near-surface layer upward to where you are standing or where thermometers measure.
- That mixing can make the measured temperature drop a bit right after sunrise, even though the sun is technically adding energy.
On some mornings you also get a small breeze as the sun starts driving local wind patterns, which can enhance the chill by increasing heat loss from your skin.
Why the warmest time isn’t noon
- A similar lag happens later in the day: it’s often warmest in mid‑afternoon, not at solar noon.
- After noon, the sun is already past its highest point, but the ground is still absorbing more energy than it loses for a while, so the temperature keeps rising.
So both the coldest (around sunrise) and warmest (mid‑afternoon) times come after the minimum and maximum in sunlight, because Earth and the air take time to cool and warm.
TL;DR: It gets colder when the sun first comes up because the ground and air are still losing more heat than they gain from the low, weak sunrise light, and early-morning mixing can bring extra-cold air up to where you feel it.
Information gathered from public forums or data available on the internet and portrayed here.