The air is holding as much water as it can. It will frequently be heavy fog or raining.
The condition that causes no condensation is when the relative humidity of the air is less than 100%. If the air is not saturated with moisture, then condensation will not occur.
The relative humidity inside a cloud is typically close to 100%. Clouds form when air is saturated with water vapor, so the relative humidity is high.
100%
The average relative humidity on a rainy day would be closer to 100 percent humidity. Rain adds moisture to the air, increasing the humidity levels to near saturation point. This leads to a higher average relative humidity compared to a non-rainy day.
When a parcel of air is saturated with water vapor the relative humidity of that parcel of air is 100%.
It is raining
100%
That would be "dewpoint"...When the air temperature falls to the dewpoint (or dewpoint rises to the air temperature), then you have 100% relative humidity.
That would be "dewpoint"...When the air temperature falls to the dewpoint (or dewpoint rises to the air temperature), then you have 100% relative humidity.
100% because, let's say that both the thermometers have a reading of 66o degrees celcius. 66o is 100% of 66o, so the relative humidity is 100%.
Relative humidity is a measure of how much moisture is in the air compared to how much moisture the air can hold at a given temperature. If the relative humidity is 100%, the air is saturated and can hold no more moisture. Lower relative humidity means the air is drier and can still hold more moisture.
Saturated