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Besides the regularly scheduled daily forecasts, National Weather Service offices around the United States as well as private forecasters issue special weather statements and watches and warnings and advisories appropriate to local circumstances.

They are issued for such things as tornadoes, severe thunderstorms, floods, and winter storm conditions such as blizzards, heavy snow, ice storms or freezing rain, high winds, and dust storms.

When threats to public safety are imminent, bulletin warnings are issued — only by the National Weather Service — and a special communications network known as the Emergency Alert System is activated. When this happens, local radio and television broadcasters interrupt their regularly scheduled programs to pass them along. Every year, the National Weather Service issues between 45,000 and 50,000 severe weather warnings. Whatever the hazard, the differences between these various levels of public notices can be worth knowing.

  A Special Weather Statement often is issued as a “first alert” to the possibility of significant weather. This kind of “heads up” also is issued when forecasters see the likelihood of such things as thunderstorms with small hail, which may not be life-threatening but could make conditions temporarily hazardous.

 A Watch, such as a tornado or severe thunderstorm watch, is issued when dangerous weather conditions like lightning, large hail, and damaging winds are possible for the next several hours. It’s time to be on your toes.

 An Advisory, such as a winter weather advisory or wind advisory, is issued when conditions are not life-threatening but still worth keeping in mind. These are especially valuable to travelers in areas experiencing such hazards as snow or winds or fog. Maybe it’s time to slow down and think ahead.NOAA WEATHER RADIOTimely weather information is readily available to anyone with an FM or AM radio or television set, and most National Weather Service forecast offices maintain a website. But what happens when things go badly? If it’s emergency preparation you’re thinking of, a battery-powered NOAA Weather Radio belongs in a disaster supplies evacuation kit.This official weather emergency radio service is the only direct link the National Weather Service has to the public. It operates from about 500 transmitters in 50 states and U.S. territories on seven frequencies in the VHF band, ranging from 162.400 to 162.550 megahertz. These frequencies are outside the normal range of AM and FM broadcasts, although some manufacturers are including NOAA Weather Radio as a special feature on some receivers.Nearly every National Weather Service office operates at least one NOAA Weather Radio transmitter broadcasting weather information 24 hours a day. The average range of these transmitters is 40 miles.During severe weather, a tone alert can be activated to cause radios equipped with the alert feature to sound an audible alarm. If you’re in the market for a weather emergency radio, check to see whether it has this special tone alarm feature.

 A Warning is issued when potentially dangerous weather is possible within a matter of minutes and residents should seek shelter. A warning means no fooling around — it’s time to take some action.

 A Severe Weather Statement often follows up on a warning, to cancel it or modify the area of concern. Also, this statement might alert residents to the presence of such hazards as funnel clouds that are not expected to touch the ground.