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Let's say there's a land-based location called Verywet on a fictional world. Assuming this fictional world follows the same laws of nature that our own planet does, would it be possible for it to continually rain over Verywet? By continual, I mean that while the intensity of the rain may be lighter or heavier at times, there is never a moment when drops are not falling from the sky.

If it is feasible what sort of environment would be required? Would the rainfall need a lot of water beneath it? Or would it need to be near a coast that brought a constant supply of storms inward?

If it is impossible for an Earth-like world, what would be needed to make it work? Other than magic.


This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See the tag description for more information.

marked as duplicate by Hohmannfan, Separatrix, J_F_B_M, Frostfyre, James Mar 4 '16 at 15:07

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    $\begingroup$ Also related. Neither question uses the hard-science tag, though, so that might be enough to differentiate them. $\endgroup$ – HDE 226868 Mar 4 '16 at 3:32
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    $\begingroup$ They actually are quite similar, though I would definitely appreciate a more "hard-science" answer if possible. $\endgroup$ – user17680 Mar 4 '16 at 3:38
  • $\begingroup$ Seattle gets pretty darn close. $\endgroup$ – RoboKaren Mar 4 '16 at 7:11
  • $\begingroup$ A tidally locked planet orbiting a Red Dwarf star might have permanent rainy zones since the atmosphere will be circulating in fixed cells. $\endgroup$ – Thucydides Mar 4 '16 at 17:52

Never is a word that is remarkably hard to use with weather. The answer is almost always "no" because there's always a statistical chance of unusual weather occurring. However, for all intents and purposes, there's no reason not to assume a region is arbitrarily rainy. All it needs is to be part of a Coriolis cell which collects a lot of moisture, and then have a giant mountain peak to encourage as much of it to condense as possible.

The Guiness Book of World Records demonstrates that lots of rain does happen:

Most rainy days - world
Mt Wai-`ale-`ale (1569m 5148ft), Kauai, Hawaii has up to 350 rainy days per annum.


Supposedly a Flash Gordon episode said "it rained on planet Mongo." I never checked it, but it sounds good enough that it should be true.

I think you can build a world where one region gets almost constant rain. Shape your continents to create rain shadows in the oceanic climate zone.