You might want to focus on frogs rather than cows as your guides for rain. Our amphibious friends are fascinating, to say the least. With more than 4,700 makes and models of these jumpy guys around the globe, frogs can range in size from a dime to more than 7 pounds (3 kilograms) in weight. In fact, they actually absorb water through their skin, rather than drinking it the boring way that humans and most other animals do [source: Defenders of Wildlife]. Talk about a party trick!
Although some croaking is normal in a frog-friendly environment, grab your umbrella if you hear them calling out with exceptional fervor. Experts attribute this phenomenon to the fact that frogs mate, then lay eggs in bodies of freshwater. So, frogs are more likely to be successful at reproduction following a good rain because there's more watery real estate to choose from. Hence, all the mate-summoning croaks that tend to occur right before a shower [source: Grandinetti]. The next time you hear a symphony of croaking, think of it as a little bit of amphibious Barry White to "set the mood," so to speak. Then grab your raincoat or get under cover ... quick!