The Weathernews App Becomes Japan's No.1 Weather App! Our Journey to Become “Japan’s Most Used” Weather App

We are proud to announce that the Weathernews App has officially become Japan’s No.1 weather app in terms of domestic users, thanks entirely to the tremendous support of our user community. This achievement is not something we accomplished on our own. It is the result of everyone who uses Weathernews every day, supports us, and shares our mission. From the bottom of our hearts, we thank you.

For us, becoming No.1 is not the finish line—it is a milestone on our path of continued evolution. In this article, we would like to reflect on our journey so far and share our renewed determination to keep moving forward.

“Why are we losing to apps that don’t even make their own forecasts?”

Today, weather information is everywhere—on TV, radio, the internet, and countless apps. Major search engines and news platforms now offer weather forecasts and radar features, and some IT companies even buy meteorological data to power their own weather apps. About eight years ago, our team responsible for personal services like the Weathernews App shared a common frustration.

“We are supposed to be professionals in weather forecasting—so why are we losing, in user numbers, to apps that don’t even create their own forecasts?”

At Weathernews, we have always had absolute confidence in our forecasting technology and the quality of our predictions. Yet at that time, our app lagged far behind the weather services provided by major portal sites in terms of users.

Driven by the desire to bring our high-precision weather data to more people, we decided to take on a bold new challenge.

In 2017, we established a specialized Growth Hack Team to enhance recognition, usability, and ultimately, user adoption.

We restructured our organization so that previously siloed departments—operations, development, design, the forecast center, and PR—could collaborate closely on one floor. By sharing all measurements, challenges, and actions transparently, we began running fast, data-driven PDCA cycles. Our single goal: to become the most used weather app in Japan.

Breaking Down the Wall of “Not Knowing”: Launching a Full-Media Exposure Strategy

No matter how good the information is, it’s meaningless if people don’t know it exists. Our first mission was to break down the wall of “I don’t know Weathernews.”

That’s why we implemented our Cross-Platform Strategy. We expanded essential weather information not only through our app, but also across all types of media and platforms — including our website, news apps, YouTube, X (formerly Twitter), Instagram, and more. At the same time, we actively pursued media coverage at our forecasting and operations sites. Through a variety of features—such as detailed weather analysis on news programs, behind-the-scenes documentaries at forecasting centers, and seasonal recommendations like cherry blossoms and autumn foliage on lifestyle shows—we openly shared what we do as a weather company. By increasing contact points across all channels, we aimed to move Weathernews from being “unknown” to “familiar.” This strategy gradually expanded public awareness of Weathernews. Furthermore, we leveraged the tendency for app traffic to surge during certain weather conditions—such as rainy days or approaching typhoons—to strategically air TV commercials at the very moments when people most needed weather information. Using weather data, we optimized our creative selection by combining factors such as timing, region, and key messaging, achieving more effective brand recognition. However, even with these efforts, catching up in user numbers to the major portal site apps—with their overwhelming reach—remained a formidable challenge.

The Greatest Value: Being the Most Accurate Forecast

“How can we get users to choose Weathernews when forecasts seem to be available everywhere?” We returned to a fundamental question—and arrived at a simple but powerful answer that defines our professional identity:

“Accuracy is everything.”

If a forecast is wrong, trust is lost. And achieving higher accuracy is something only a company that creates its own forecasts can truly deliver. We rigorously evaluated and improved our forecasts, and as a result, we have been recognized by third-party organizations as Japan’s No.1 in forecast accuracy for three consecutive years.

This was made possible through collaboration with our Weather Reporters—users who share real-time, on-the-ground weather updates through our app. With this foundation of trust, we became even more confident in delivering information that users can rely on.

Matching Major Tech Companies with Cutting-Edge Cloud Technology

Accuracy and awareness alone aren't enough—if an app is difficult to use or fails when it's needed most, it loses its value. Ease of use and stability are the lifelines of any essential service. We therefore focused heavily on strengthening our IT infrastructure. By adopting the latest cloud technologies and analyzing detailed user behavior—what content people viewed, when, and how quickly—we continuously improved app performance. During typhoons and earthquakes, when traffic surges dramatically, our servers must never fail. We reinforced our systems to ensure the app remains fast and reliable even during emergencies. This investment also drove content innovation. For example, our highly popular rain cloud radar now delivers industry-leading, high-resolution forecasts—up to 30 hours ahead, updated every 10 minutes, at 250-meter granularity.

Today, Weathernews has built an IT foundation as robust as that of any major tech company.

Winning Together with Our Weather Reporters

Forecast accuracy is vital—but users ultimately turn to weather apps to help them make decisions: "Can I hang my laundry outside today?" "What should I wear?" To support these daily decisions, we developed a wide range of original lifestyle forecasts, using valuable data from our Weather Reporters. These include power outage risk forecasts, weather pain alerts, road freezing predictions, and flood warnings—over 50 new services each year. We knew that this unique collaboration with our community would become the strongest reason people choose Weathernews.

Then, finally, the day came.

In September 2025, the Weathernews App became Japan’s No.1 weather app in monthly active users—the most used weather app in the country.

When the announcement was shared internally, our chat channels erupted with messages like "Finally!", "We did it!", and "Amazing work!" The frustration we felt years ago—"Why are we losing to apps that don't make their own forecasts?"—had finally transformed into victory.

Eight years of teamwork had paid off: every morning we reviewed metrics together—app traffic, notification open rates, banner click rates, user retention—and refined our strategies. Our forecast center never compromised on accuracy, and every team member kept asking, "What do we need to do to truly earn users' trust?"

Throughout this journey, our Weather Reporters were always with us—their on-site updates continually improving our forecasts. This achievement is, above all, a shared victory.

A One-of-a-Kind Community, Expanding to the World

Becoming Japan's No.1 weather app is a tremendous honor—a result of years of effort and collaboration with our users.

But this is not our final destination. This is where our real journey begins.

As weather increasingly impacts lives and businesses around the globe, our responsibility grows. From disaster prevention to business optimization and climate risk response, there is still so much more we must do.

Our greatest strength lies in the strong, weather-centered community we've built with our Weather Reporters over the past 20 years. With 40 years of experience leading the weather business since our founding, we will now expand this community-driven approach—across Japan, and from Japan to the world.

Under our unwavering mission to enrich lives and protect lives, we promise to keep evolving—never stopping, always advancing.

And finally, to everyone who uses Weathernews—thank you, sincerely, for your continued trust and support. We look forward to walking through this next chapter together with you.