During the winter, in the beginning of the second blessing of Shemone Esray we say “Mashiv HaRuach U’Moreed ha’Gashem”. This phrase is not a blessing for rain, but is a praise of G-d. We are saying that G-d sends the wind and rain to the places where it is needed. G-d knows the exact amount of rain and wind needed in every place and sends that exact amount to the area. Every drop is measured out to make sure that not a single extra one falls where is it not needed. We say this only during the winter because this is the rainy season when we actually see this miracle before our eyes.