I stopped by the local library in Newport the other day, and this science book for young people caught my eye called, Can It Rain Cats And Dogs?: Questions and Answers About Weather, by Melvin & Gilda Berger, 1999. The first page had this to say in reply to the question.
"Can it rain cats and dogs? No--but it can rain frogs and fishes! In the United States, frogs fell on Tennessee in October 1946 and on Arkansas in January 1973. Fish fell on Glamorgan, Wales, in 1859, on Frankston, Australia, in 1935, and on Louisiana in 1947--each during the month of October. Every time, rainstorms swept up the animals, which then came down with the rain.
People like to say, ‘It’s raining cats and dogs’ when it is raining very hard. The saying comes from an old belief that cats bring rain and dogs bring wind. But don’t believe it. While it can rain frogs and fishes, it can’t rain cats and dogs!"
I then “googled” the phrase and came up with a couple more links, but the jury’s still out on cause of this phenomenon. Some sources say that yes, it is true that small creatures get swept up in storms and are “rained” down in another location, and these websites cite a variety of historic instances of these phenomena. Others say no, it only appears that the animals come in the rain, because many amphibians, in particular, come out of hiding in large numbers when it rains. Still other sites list a wide range of odd paranormal explanations, from time/space travel to poltergeists and extraterrestrials.
Waterspouts over St. Thomas, photo by Jan Havelka
Wikipedia has a comprehensive entry on the subject (including cultural and literary references, origins of the phrase “raining cats and dogs”, and more), beginning with this paragraph:
“Raining animals is a rare meteorological phenomenon, although occurrences have been reported from many countries throughout history. One hypothesis that has been offered to explain this phenomenon is that strong winds travelling over water sometimes pick up creatures such as fish or frogs, and carry them for up to several miles. However, this primary aspect of the phenomenon has never been witnessed or scientifically tested.”
A similar accounting is given on the “Scienceline” website:
“Raining fish is not a common weather phenomenon. Fewer than 10 occurrences have been reported in the past year, according to a news search, so local five-day forecasts probably won’t include fish showers. Still, people have reported such events for centuries.”
“Now that scientists have advanced technology like Doppler radar, they are less reliant on personal accounts. Fewer people are asked to describe the odd objects they see falling from the sky, says Cerveny, who is also a professor of weather and climate at Arizona State University. Also, people are less likely to report any strange occurrences now than they were 100 years ago. Cerveny explains that today, logical explanations through science are more readily available, so there is less mysticism behind strange weather phenomena. ‘They tend to sound more kooky now if they report it,’ he says. Even though fewer personal accounts of strange weather have not necessarily hurt meteorology, ‘maybe it has taken away some of the fun of it,’ says Cerveny.”