Sea surface temperature the passing of a hurricane primarily as the result of mixed layer deepening and surface heat losses. In the wake of several day long Saharan dust outbreaks across the adjacent northern Atlantic Ocean, sea surface temperatures are reduced 0.2 C to 0.4 C (0.3 to 0.7 F). Other sources of short-term SST fluctuation include extratropical cyclones, rapid influxes of glacial fresh water and concentrated phytoplankton blooms due to seasonal cycles or agricultural run-off. The Atlantic Multidecadal Oscillation (AMO) is important for how external forcings are linked with North Atlantic SSTs. El Niño is defined by prolonged differences in Pacific Ocean
Significant weather advisory Significant weather advisory A significant weather advisory (alternately termed as a "significant weather alert" or a "special weather statement", the terminology varies depending on the local National Weather Service Weather Forecast Office) is issued when Doppler radar indicates a strong thunderstorm is producing small hail or high winds whose strength does not reach the criteria to be designated a severe thunderstorm. It does not necessarily account for lightning or flooding. This alert product was created in the early 2000s, and is sometimes a precursor to a severe thunderstorm warning. Many versions of the First Warning weather alert system used by