Most people use the term “monsoon” to refer to getting dumped on by rain. This annual phenomenon is the change in wind direction from the usual westerly breezes most of the year to more of a south to southeast direction during the summer months. This flow of air brings moisture up from both the Gulf of Mexico and the Gulf of California. Much-needed rainfall is headed across the Desert Southwest this week. It is a relatively late start to the monsoonal season.
Due to the excessively dry ground across the Southwest, temperatures have been allowed to soar into the triple digits across the region over the past few days. When the ground is dry, more of the sun's energy heats the ground and lower portions of the atmosphere. On the other hand, when the ground is wet, less of the sun's energy is available for heating as it is used during the evaporation process.
India has two monsoons (or rainy seasons). The summer monsoon season in India, otherwise known as the southwest monsoon, which lasts from June to September and affects the whole of India. Then the northeast or winter monsoon brings seasonal rainfall to Southeast India from October to December. These two seasons provide about 90% of the years rainfall to the area.
