while the philippine atmospheric, geophysical and astronomical services administration assigned names to tropical cyclones which moved into or form as a tropical depression in their area of responsibility between 135°e and 115°e and between 5°n and 25°n even if the cyclone has had a name assigned to it by the japan meteorological agency. tropical depressions that were monitored by the united states' joint typhoon warning center were given a number with a "w" suffix. on average, 27 storms form in this basin every year.