Regional Powdery Mildew Maps

Powdery Mildew Advisory
The maps displayed on this site are generated through a reliable computer model based on accurate weather data collected from several sites throughout each region. The powdery mildew index is an indication of climatic conditions which may be conducive to development of powdery mildew disease. It is possible to have the disease present and active at economically damaging levels even when the powdery mildew index indicates a low likelihood of conditions favoring rapid development of the disease. Frequent field scouting by a qualified PCA is recommended.

North Valley



Central Valley



South Valley



Greenfield



Paso Robles



Santa Maria