Pacific Ocean To determine the phase of ENSO, the most recent three-month sea surface temperature average for the area approximately to the southeast of Hawaii is computed, and if the region is more than above or below normal for that period, then an El Niño or La Niña is considered in progress. In the tropical western Pacific, the monsoon and the related wet season during the summer months contrast with dry winds in the winter which blow over the ocean from the Asian landmass. Worldwide, tropical cyclone activity peaks in late summer, when the difference between temperatures aloft and sea surface temperatures
Significant weather advisory broadcast television stations have begun including significant weather advisories into their systems, however, these systems usually classify such an advisory terms such as "Heavy T-Storms", "Heavy Storms" or "Strong T-Storms" (terms used by the system prior to the inclusion of the product). The National Weather Service in the United States issues a significant weather advisory for strong thunderstorms (and occasionally, other weather situations such as downbursts) that may pose limited to no threat to life and property; it is typically issued if the hail size in a thunderstorm is one-half to one inch in diameter, and/or winds of 35 to