The creators of Dark Sky, who sold their popular weather app to Apple in March 2020, are back with a new take on weather forecasting. The team recently announced the launch of their new app, Acme Weather, which they claim offers a better and more reliable forecast than the one they had at Dark Sky. The app will also offer a range of unique weather notifications, including fun ones like alerts about rainbows and beautiful sunsets.

Unlike typical weather apps, Acme Weather’s forecast is supplemented with a range of alternate predictions for better accuracy.

Dark Sky co-founder Adam Grossman explains in an introductory blog post that the app’s homegrown forecasts will leverage different numerical weather prediction models, satellite data, ground station observations, and radar data, making its forecast fairly reliable.

However, the app will also feature additional forecast lines that show the other possible outcomes as gray lines on its graphs.

“Forecasts are often wrong — it’s the weather, right? It’s one of the hardest things to predict,” Grossman told TechCrunch via a telephone interview. “And our biggest pet peeve with a lot of weather apps is you just get their best guess, and you don’t know how certain they are.”

Having an understanding of the alternatives helps people plan for big events, he noted.

“I find it most useful for winter storms, where, maybe the storm starts out in the morning, and you’re going to get snow, but maybe there’s also a possibility it holds out a little bit later — to the afternoon — in which case it’s rain,” Gross explained. “Being able to just see that right there on the timeline just gives you this intuitive sense of whether, do all the models agree, and you’re getting snow? Or do half of them say snow and half of them say rain?”,” he says.”

This type of weather data could make for a valuable product, not just for consumers, but for other developers, too.

At Dark Sky, the team had offered its weather API to developers for a fee. After being acquired by Apple, the team worked on creating WeatherKit, the developer toolkit that provides access to Apple’s weather data on a subscription basis. Grossman said the team hasn’t yet decided if a developer API will be a part of Acme Weather’s offering.

Instead, Acme Weather is a $25 per year consumer app, with a two-week free trial. This helps to cover the costs involved with pulling in the different weather models and resources, which can be expensive.

“Most of our time has been spent on building our own forecast — our own data provider, in a way. And this lets us do things like build multiple forecasts…[and] create any map we want, rather than having to rely on a third-party map provider,” Grossman noted.

At launch, the app offers a range of maps, like radar, lightning, rain and snow totals, as well as wind, temperature, humidity, cloud cover, and hurricane tracks.

Another feature, Community Reports, lets users share information about their current conditions to improve the app’s real-time weather reporting.

While Dark Sky had become a favorite weather app because of its uncanny ability to predict when it would begin raining in your location, Acme Weather aims to improve on this and even have some fun.

The app includes built-in notifications for typical things, like rain, nearby lightning, community reports, government-issued severe weather alerts, and more. It’s also going to experiment with alerts like rainbow predictions or those to identify when you might see a beautiful sunset.

These will be available in a special “Acme Labs” section of the app, and Grossman said they’ll be conservative with their predictions, given the difficulty.

Users will also be able to customize their notifications to focus on weather events they care about, like winds or UV index, or the possibility of rain over the next 24 hours.

Being able to try new ideas is part of what drew the team back to building an indie app, Grossman noted.

“I absolutely love Apple…but as a big company, it’s difficult to try weird, new, experimental ideals. If you have a billion users, mistakes are costly,” he tells TechCrunch. “There’s long software development cycles, there’s a lot of stakeholders, this idea of being able to try a bunch of things, I think, is interesting.”

Acme Weather is currently available on iOS. An Android version is planned.

The team is bootstrapped and includes co-founders Josh Reyes and Dan Abrutyn, also previously of Dark Sky. The small workforce includes both former Dark Sky team members and new hires.