Sometimes we see swallows flying very low, almost touching the ground; at other times, we observe a large number of dragonflies gathering in a swarm, flying just a few meters above the ground.
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| Dragonflies flying low signal impending rain (Image: Research) |
These unusual phenomena signal the onset of rain. Normally, swallows and dragonflies fly around to catch insects for food. However, when rain is approaching, the humidity in the air increases, causing the wings of insects to become wet and their bodies to become heavy, preventing them from flying high. At this point, swallows and dragonflies must fly very low to catch their prey.
In nature, there are still many phenomena that can forecast rain. For example: The surfaces of tiles, stone columns, jars, and even household items that are painted suddenly become damp, or a layer of mist appears on their surfaces. All these phenomena indicate that it is about to rain within a few hours. The temperature on the surfaces of these items is relatively low, and the moisture in the air can condense into tiny droplets upon contact.
In fact, humans are also very sensitive to the approach of rain. Just try touching your hair, and you’ll immediately notice: when the weather is dry, your hair feels dry, but during overcast weather, your hair becomes damp.
