Weather buoy tropical Pacific Ocean helped study the El Niño-Southern Oscillation. Moored weather buoys range from in diameter, while drifting buoys are smaller, with diameters of . Drifting buoys are the dominant form of weather buoy in sheer number, with 1250 located worldwide. Wind data from buoys has smaller error than that from ships. There are differences in the values of sea surface temperature measurements between the two platforms as well, relating to the depth of the measurement and whether or not the water is heated by the ship which measures the quantity. The first known proposal for surface weather observations at
Significant weather advisory 58 miles per hour. The product is mainly used by forecast offices located in the National Weather Service's Southern Region Headquarters. A significant weather advisory or warning is not an official National Weather Service product, instead it is issued within a special weather statement. Special weather statements are also used for any type of weather approaching watch/warning/advisory levels. Many NWS offices do not use significant weather advisories, instead issue normal special weather statements mentioning much of the same text used in such an advisory. If severe weather is detected, alerts (mainly a severe thunderstorm or tornado warning) are issued by