Glume blotch and leaf blotch diseases of wheat can be caused by septoria tritici blotch (Zymoseptoria tritici) and staganospora nodorum blotch (Parastagonospora nodorum), which are both favoured by wet conditions. The humidity model estimates risk of septoria tritici blotch infections in winter wheat. Risk of attack is assumed after 20 hours with continuous wetness. A wet hour is defined as minimum 0,2 mm precipitation in an hour or min. 85% relative humidity.