A campaign that follows the sun
UV-triggered screens in 17 Belgian rail stations told summer travelers the day's UV index, city by city. The campaign ran when the sun did, and paused when it didn't.
Partenamut, a Belgian health mutual, wanted to talk about sun protection at the exact moment the risk is real: when people are outside, in summer, under a high UV index. A calendar-planned campaign can't do that. It spends the same budget on gray days as on scorching ones, and the analysis showed why that matters: of the 62 days of a Belgian summer, only around 47 exceed UV index 3 in Uccle.
The campaign was triggered by the live UV index instead of a schedule. Screens activated at UV 6 and above at launch, relaxed to UV 5 for the final stretch. Budget saved on low-UV days wasn't lost: it extended the flight by a full week, for 28 days live between June 29 and July 31. Diffusion ran on 100 vertical screens across 17 major stations in Brussels and Wallonia (Live Station network, Bauer Media). The creative started life as a poster and was reworked for the vertical screen, versioned per city in real time: "Today in Brussels, UV index 6."
Stations in summer concentrate exactly the right audience: families heading out, many toward the coast. Belgian rail carries 9.5 million leisure travelers in July and August, over a million of them to coastal stations (+25% vs 2019). That flow rises with good weather, the same trigger as the campaign. On the platform, waiting time and the absence of distraction let the message land: 89.5% of contacts happened between noon and 4 pm, the hours when UV peaks. The screen gives the day's UV index for the city you're standing in. It serves rather than sells, and that is what sticks: context-matched messages earn +17% spontaneous recall and +6% on brand trust and preference (The Moments of Truth, Bauer Media Outdoor, JCDecaux, Posterscope).
Same campaign, three cities: the creative carries each city's live UV index. Live Station network, Bauer Media.
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