Okay I will, Maritime tropical (mT) air masses are warm, moist, and usually unstable. Some maritime tropical air masses originate in the subtropical Pacific Ocean, where it is warm and air must travel a long distance over water. These rarely extend north or east of southern California.
In air mass. The maritime Tropical (mT) is the most important moisture-bearing and rain-producing air mass throughout the year. In winter it moves poleward and is cooled by the ground surface. Consequently, it is characterized by fog or low stratus or stratocumulus clouds, with drizzle and poor visibility.
