Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Are there any atmospheric condition under which a visible raindrop can fail to hit the ground by evaporating first? I imagine this would require a large vertical temperature difference, and possibly the rain forming very high up. Has anything like this been observed experimentally, or if not - is it possible to perform a calculation to show whether this is plausible?

share|cite|improve this question
up vote 31 down vote accepted

Yes, most certainly, and meteorologists call this kind of rain Virga (see Wikipedia page of the same name).

These are the salient and more interesting points of the Wiki article:

  1. Often it is falling ice crystals that undergo compressional heating as the fall from greater heights, where the pressure is very low;

  2. It is very common in desert and temperate climates: Western United States, Canadian Prairies, the Middle East and Australia.

  3. It plays a role in seeding non-Virgal (i.e. reaching the ground as liquid) rain when virgal material is blown into another supersaturated cloud and begets rain through nucleation;

  4. Its evaporation, with its high associated latent heat, means that virga draws a great deal of heat from the surrounding air, thus begetting violent up and downdraughts hazardous to aeroplanes;

  5. Almost all (sulphuric acid) rain on Venus is virga. Presumable all rain on the early Earth was too.

share|cite|improve this answer
+1 for point 5 - interesting... even though it's a quote :-P – Heliac May 25 '14 at 10:47
+1, already covered my (attempt to) answer + added other peripheral information – Nikos M. May 29 '14 at 22:46

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.