<P> A major part of modern weather forecasting is the severe weather alerts and advisories that the national weather services issue in the case that severe or hazardous weather is expected . This is done to protect life and property . Some of the most commonly known of severe weather advisories are the severe thunderstorm and tornado warning, as well as the severe thunderstorm and tornado watch . Other forms of these advisories include winter weather, high wind, flood, tropical cyclone, and fog . Severe weather advisories and alerts are broadcast through the media, including radio, using emergency systems as the Emergency Alert System, which break into regular programming . </P> <P> The low temperature forecast for the current day is calculated using the lowest temperature found between 7 pm that evening through 7 am the following morning . So, in short, today's forecasted low is most likely tomorrow's low temperature . </P> <P> There are a number of sectors with their own specific needs for weather forecasts and specialist services are provided to these users . </P> <P> Because the aviation industry is especially sensitive to the weather, accurate weather forecasting is essential . Fog or exceptionally low ceilings can prevent many aircraft from landing and taking off . Turbulence and icing are also significant in - flight hazards . Thunderstorms are a problem for all aircraft because of severe turbulence due to their updrafts and outflow boundaries, icing due to the heavy precipitation, as well as large hail, strong winds, and lightning, all of which can cause severe damage to an aircraft in flight . Volcanic ash is also a significant problem for aviation, as aircraft can lose engine power within ash clouds . On a day - to - day basis airliners are routed to take advantage of the jet stream tailwind to improve fuel efficiency . Aircrews are briefed prior to takeoff on the conditions to expect en route and at their destination . Additionally, airports often change which runway is being used to take advantage of a headwind . This reduces the distance required for takeoff, and eliminates potential crosswinds . </P>

Three occupations in which weather forecasts are essential