Sea surface temperature monitor and predict the El Niño phenomenon. Weather satellites have been available to determine sea surface temperature information since 1967, with the first global composites created during 1970. Since 1982, satellites have been increasingly utilized to measure SST and have allowed its spatial and temporal variation to be viewed more fully. Satellite measurements of SST are in reasonable agreement with in situ temperature measurements. The satellite measurement is made by sensing the ocean radiation in two or more wavelengths within the infrared part of the electromagnetic spectrum or other parts of the spectrum which can then be empirically related to
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