In the early months of 2023, I noticed that the weather service hosted by the Swedish Meteorological and Hydrological Institute (SMHI) underwent a significant change. SMHI decided to dismantle the UV-index forecast service, and instead began to refer to an incomplete web application that the Radiation Safety Authority (Strålsäkerhetsmyndigheten) offers.
Since the service was discontinued, the demand for a reliable source of realtime UV data and forecasts grew significantly. Suddenly, there was a gap in the search results offered by major search engines that needed to be filled by a new service. Behold, UV-Kollen was born.
Why we need a reliable UV index service
The UV index measures the amount of ultraviolet radiation from the sun that reaches the earth and can cause sunburn. It varies depending on latitude, season, time of day, and factors such as topography, ozone, and cloudiness. A high UV index means strong radiation and the need for sun protection.
Recurrent sunburn can lead to various types of skin cancer in the long term. Every year, 5,000 Swedes are affected by the more serious type of malignant melanoma. Of these, 500 people die each year.
A UV index service that serves the user with reliable, actionable, and simple data not only gives the user a chance to take precausions; it also contributes meaningfully to public health and safety by promoting proactive sun protection measures.
Development approach
In essence, the idea was simple. Leveraging data streamed from OpenWeather – a british company that aggregates global weather data – I built a website that processes the data and refines it into user-friendly predictions. The website is built on using Next.JS and has been developed with SEO, usability and efficiency in mind.
Serving data for all Swedish cities, it periodically fetches a forecast of that city, and uses that data to give the user insights about recommended sun exposure.
UV-Kollen today
Today, UV-Kollen comes up first in all Google searches related to UV forecasts in Sweden. It receives on average 100k visits during the summer months. A survey hosted on the website show that 93% will continue to use UV-Kollen, and that the average rating out of 10 is 8.9. It is arguably Swedens biggest UV index service, and has been featured in multiple news outlets:
Developing the website is ongoing and new changes are being made every year. You can check out the public respository of UV-Kollen, or consider donating to ensure that the project lives on in the future.