A Winter Storm Watch is in Effect…What does this mean?

By David Nicosia, Warning Coordination Meteorologist

National Weather Service Binghamton NY

When the National Weather Service issues a WINTER STORM WATCH, what does this mean? Does it mean that our area is definitely going to get hit with heavy snow or ice? What is the difference between a WINTER STORM WATCH and a WINTER STORM WARNING? Recently, the National Weather Service in Binghamton issued a WINTER STORM WATCH for much of upstate New York and northern Pennsylvania and there seemed to be a lot of confusion about what this meant. The purpose of this article is to explain the terminology that we use to help prepare you for winter storms and all other natural hazards.

The Definition of a Watch

The National Weather Service issues a WATCH for a natural hazard (flood, winter storm, tornado, severe thunderstorm, high wind) when the POTENTIAL exists for that hazard to occur in the WATCH area. It means there is still uncertainty as to when and if this particular hazard is going to occur. Basically, the hazard is a POSSIBILITY, NOT A CERTAINTY. In the case of a WINTER STORM WATCH, it means that heavy snow (or ice) as defined as greater than 6 inches in a 12-hr period (or ½ inch of ice or greater) is only a possibility in the WATCH area. There is still a chance that the storm with the heavy snow (or ice) could miss our area. For winter storms, WATCHES are issued 24 to 72 hours in advance of the storm. During a WATCH, persons should keep up with the latest forecasts and updates. If you plan on traveling in the WATCH area, you may want to consider delaying travel or finding an alternate route. There is still some time to prepare if the storm becomes more certain or imminent.

The Definition of a Warning

When a WARNING is issued for a natural hazard, it means that the hazard is imminent or very likely to occur in the WARNING area. Warnings are reserved for life-threatening weather hazards. A WINTER STORM WARNING means that heavy snow or ice is expected to occur in the next 12 to 24 hours. All necessary preparations should be made to keep you and your family safe. Travel in the WARNING area is discouraged because there is a likelihood of road closures and/or extremely treacherous road conditions. In addition, you may want to make sure you have an adequate supply of food in case you are stranded at homes for a few days. You will want to check your alternate source of heat in case of power outages or plan to stay somewhere that has an alternate source of heat.

The Definition of an Advisory

The National Weather Service also issues ADVISORIES for less serious weather hazards. ADVISORIES are issued for winter weather, snow and ice, urban and small stream flooding, wind, wind chill, heat and dense fog. An advisory means conditions are not expected to become life-threatening if proper precautions are taken. It means that the weather will cause inconveniences but should not cause any major problems. In the case of winter weather, a WINTER WEATHER ADVISORY is issued for less serious snow and ice events. When snowfall is expected to average between 4 and 7 inches or for any accumulation of ice, a WINTER WEATHER ADVISORY will be issued. ADVISORIES are generally issued out to 12 or 24 hours in advance for winter weather. When a winter weather advisory is in effect, it means that snow and ice will cause roads to become slippery. Travel is not recommended during advisories. But, if you must travel, take it slow and leave plenty of extra distance between you and the vehicle in front of you.

NOAA Weather Radio

One of the best ways to receive information about winter weather watches, warnings and advisories is through NOAA weather radio. NOAA weather radio is the “Voice of the National Weather Service”. The NWS in Binghamton maintains 13 weather radio stations in central NY and northeast PA providing broadcasts of warnings, watches, forecasts and other hazard information 24 hours-a-day. Most weather radios are equipped with a special alarm tone feature that can sound an alert and give you immediate information about a winter weather or severe weather situation any time of day. Weather radios can be purchased at most stores that sell electronics for about the cost of a pair of shoes. Regular radios normally do not pick up the weather radio frequencies.

So, the next time a WINTER STORM WATCH is issued, remember that there still is a chance that the storm could miss us! This is a good time to prepare in case the storm hits. Only when a WINTER STORM WARNING is issued, is it highly likely that heavy snow or ice will occur.

For comprehensive weather forecast and warning information, you can also check out the National Weather Service’s new internet web site at: http:/weather.gov To get to NWS Binghamton, all you have to do is go to weather.gov and click on central NY or northeast PA and you will be directed to our site. You could also reach us at http://www.nws.noaa.gov/er/bgm If you have any questions, send me an e-mail at: David.Nicosia@noaa.gov