(FORTUNE Magazine) – Never mind the wilting crops and suffering farmers -- awful weather can be great news when the weather is your business. Although they are loath to admit it, forecasters do best during periods of extreme weather, and this summer's drought is as welcome for them as a soaking thunderstorm in South Dakota. Among the most visible winners is cable TV's Weather Channel. After six years of near obscurity, the Atlanta-based operation, owned by Landmark Communications, is attracting viewers and advertisers to its round-the-clock schedule of endlessly repackaged meteorology. Viewership usually drops in midyear, but this July it rose to more than eight million households a week, up 200,000 from April. For commodities brokers, food processors, utilities, airlines, municipalities, even department stores, up-to-the-minute weather information has bottom line urgency. They pay private forecasters about $50 million a year, and the business is swelling. Is the information worth it? The federal government's National Weather Service collects most of the data. Private prognosticators get it for a nominal fee and organize it for individual customers. Weather is so difficult to predict more than a day or two in advance that the Weather Service's largest supercomputers are still unequal to the task, except in the most general ways. Says Peter Leavitt, executive vice president of Weather Services Corp. of Bedford, Massachusetts: ''We can tell you if it will be warm or cool, wet or dry, with about 60% accuracy on temperature and 55% on precipitation, for up to a month -- as long as you're not fussy about which days.'' Which means you could flip a coin and do almost as well. - W.E.S.