rain bubble

The colloquial, commonly used way of referring to the small air bubble generated by a raindrop falling into a puddle or onto any other water surface. These bubbles usually appear when it is raining hard and large drops are falling. According to popular belief, as long as these bubbles appear it will not clear up, which has a scientific basis. The release of air dissolved in the water, as a consequence of the change in the solubility of the former in the latter with temperature (the water of the raindrops is much colder than the water they fall into), accounts for the appearance of the little bubbles.