Increasing interests in a better knowledge about how several influences of weather and climate on human’s life and their activities lead this work to study the meteorology applied to sports. This paper presents a detailed analysis about the meteorological service performance on the 52° World Championships of Modern Pentathlon, since the job routine description during the competition until the validation of the forecasts released to the community (athlets, coachs, organization committee and audience), taking into account the data collected in competition site. As conclusions, was verified that a specific service like this one is really necessary in a competitive sports environment, and that the forecasts had a satisfactory role on the support for the best performance of the athlets