With today’s news that Dark Sky is now available for Android and that the developers are considering adding support for Australia, it’s appropriate to look at an Australian alternative named Brolly that’s providing hyper-local rain forecasts right now.

Like many weather apps, Brolly tells you when it’s going to rain but the difference is that it tells you when it’s going to rain on you, wherever you are. It’s using freely-available radar images provided by the Bureau of Meteorology, and combining that information with your current location on their server to answer the questions they know you really care about: “How long until it starts raining?” and then, “How long until it stops?”

Brolly’s developers Alex North and Nik Youdale work on the app as a side project to their main jobs. Neither of them are meteorologists, and Brolly is simply designed to present existing weather data in a new way. Alex says, “I used to look at the radar animations on the BOM’s web site and try to play them forward in my head to work out when it would rain. It seemed like you should be able get a computer to do that fairly well. I knew other people did the same.”

Brolly uses machine learning and computer vision algorithms on the server-side to analyse rain patterns and predict rain for you. “Our predictions are reasonably accurate out to about an hour, and really great inside half an hour.”

I can attest to that. When I first heard about Brolly, I was standing outside a cafe. A friend told me we had to move because it was going to rain “in 5 minutes”. I asked him how he knew (it was pretty specific) and he showed me the app on his phone and explained how it worked. That discussion went on a little too long, and we got rained on. I was so impressed at the accuracy of the information provided and the simple usage scenario that I downloaded the app then and there.

Brolly might not replace your existing weather app, but it will complement it well. Alex says simply, “People might still want another weather app for longer term forecasts and other details, but Brolly has the answers when it comes to rain.”

The most useful part of the app is the push notification system – Brolly fairly reliably tells you when rain is coming, starting about an hour out. Sometimes it gets a little tricked by weather patterns, but I prefer it to err on the side of caution. Push notifications are free for a trial period, and thereafter cost $3.85 a year as an in-app purchase. That goes to recoup the costs of running the prediction server. It’s a great investment in keeping yourself dry.

If you want to try out Brolly, grab it now from Google Play. If you’ve got an iOS device in your life, you can find it on the App Store, too. For more information, head over to or follow @thebrollyapp on Twitter.

Brolly - Rain alarm & radar
Brolly - Rain alarm & radar
Developer: 25Fifteen Pty Ltd
Price: To be announced


    1. I’ve been using Rain Alarm for years which doesn’t tell you when it’s going to rain but it does tell you when rain is approaching with certain intensity, from a certain direction in a certain radius. I love it. I’ll check out Brolly. Unfortunately I live in Darwin so it’s going to be a long time before it rains again 🙂 It’s common for full blown thunder storms to run out of steam a km away, turn 45 degrees north or south or split in two and go around. Not super confident it will work that well unless it really has predictive / learning capability but I’ll give it a chance