A supposedly active rock instability was instrumented at Socoa (municipality of Ciboure, France). The objective was on the one hand to diagnose the activity of the instability, and on the other hand, to understand the meteorological-marine phenomena and associated processes which could play a role in its destabilization. Analysis of in situ data (extensometers, temperature probes, weather data) shows that the instrumented slab moved by about 1.6 mm during the first year of measurement. The phenomenon which contributed the most to this small accumulation of deformation is the slab creep under the effect of daily temperature cycles. The amplitude of this yet undocumented phenomenon depends on the temperature conditions: the greater the amplitude of daily temperature, the greater the induced movements. The occurrence of rain reduces the amplitude of this phenomenon. The intensity of this phenomenon is highly likely to increase in connection with climate change, as this coastal zone is supposed to endure an increase of droughts and heat records.