If I could go the rest of my life without getting caught in the rain, I would. Like a cat, I turn into a grouch when I'm soaked, and growing up in humid East Texas with a headful of coarse, frizzy hair, my disdain for rainy days only worsened. I know I'm not alone in thinking this way, and thanks to the weather's freaky behavior--hello, Polar Vortex--a pack of data-driven apps have sprung up around the very idea of keeping me dry.  

Right at this very moment, Adam Grossman is working on one of them from his home in rustic Willington, Connecticut. Grossman is one of the two guys who founded Dark Sky, which is perhaps the hottest paid weather app on the market right now. The iOS app has been downloaded 600,000 times since launching two years ago and points to the future of what these data-driven weather apps might become.

No Need for a Weather Expert

In terms of interfaces, Dark Sky's is flat, with black and white animations of rain and thunder that look like they were drawn with a Sharpie. But what makes Dark Sky stand out is its pragmatic approach. One view not only displays the temperature but what that temperature feels like. Another provides a seven-day forecast, with the option to tap on each day for a precipitation breakdown. At $3.99, such clairvoyance doesn't come cheap, relatively speaking, but the app, which rolled out an iOS 7 update in January, remains one of the App Store's most popular. 

"When we started building Dark Sky in 2008, there was no one in this space," recalls Grossman, who spends most of his days stationed in front of a MacBook Pro monitoring a cluster of 60 to 70 virtual machines that pull in all sorts data from radars, the National Weather Service, and the United Kingdom's Met Office, which gathers data worldwide. 

But isn't predicting the weather, well, hard? Grossman and Dark Sky co-founder Jay LaPorte aren't meteorologists by any stretch, but they've come to understand enough of the data to toy around with ways of presenting it. To do so, Grossman captures the data and converts it into images, using computer-vision and statistical algorithms, which he can then analyze the way a meteorologist might, assessing whether a storm is growing and precisely where it's headed. These "glorified cheats," as Grossman called them in an Inc. interview last summer, might tick off the pros who studied natural science, but they get the job done. 

More importantly, people are willing to pay for it. Most weather apps cost money, enabling developers to bootstrap indefinitely without having to take funding. For its part, Dark Sky held a Kickstarter campaign in 2011 and raised $40,000 to create the app; Grossman says it has been bootstrapped--and profitable--ever since.

The Importance of Smart Data and Great Design

In recent months, Grossman has found weather apps have become a "kind of a playground for designers," because the data is free and there's no shortage of ways to present it. So data-driven weather apps offer developers some creative freedom. Whereas Yahoo Weather and the Weather Channel's apps--both the top and No. 2 free weather apps in the App Store this week, respectively, according to data provided to Inc. by App Annie--appear to be little more than brand extensions, indie developers have gone above and beyond presenting the temperature with a pretty backdrop.

"The smaller shops are making the better apps because there are one or two people doing everything," says Grossman. If something doesn't feel quite right, they can tweak it right then and there; there's no bureaucracy slowing down decision making the way it might at a large corporation. The downside, of course, is that when a server goes down in the middle of the night and you're a small shop, you're the only one who can fix it. ("I never get any sleep," he says.)

The success of Dark Sky and other weather apps rests obviously on the quality (and consistency) of their data and how it's presented. "Big Data is only half the battle," says Ryan Jones, who created Weather Line, an iPhone app that rocketed to No. 19 in the App Store when it launched. "You have to present it in an actionable way to the users."

Other developers, like Contrast founder David Barnard, prefer to outsource the data gathering entirely. Barnard, who launched his color-coded Perfect Weather app in 2012, partnered with Weather Decision Technologies (WDT), an Oklahoma company that provides data as well as white label weather apps to 70 or 80 media companies, including weather app developers and local TV stations like ABC 13 in Houston. WDT even sells two iOS weather apps of its own, Weather Radio and RadarScope.

"We kind of provide the basic things," says Mike Wolfinbarger, WDT's vice president of mobile development. "Current conditions, forecast, an interactive map (with the ability to zoom in), and push notifications."

The Deepest Dive Doesn't Necessarily Win 

As for Barnard, who lives in San Marcos, Texas, just south of Austin, he says he created the app that he wanted, one that emphasized radars or heatmaps. "There are literally hundreds of different weather apps out there, and I've always been surprised at how apps like Yahoo Weather won design awards," he says. "That kind of app makes sense if you live somewhere like Silicon Valley because they don't get a lot of rain, but my goal... was really to provide a more intuitive interface and a look at the weather that's more for people who actually have weather." 

And in a way, that's where weather apps are headed. "If you just care about the temperature and want to see a beautiful picture, Yahoo Weather is great," Barnard says. "Others are focused on whether you need your umbrella in the next two hours. You can go as deep or as shallow as you want, as long as there is a market for that." 

In other words, the future looks bright, if not a tad crowded.