This image is of the homepage for the National Weather Service on July 11, 2008. The map of the United States is color coordinated with the advisories, watches, and warnings for that day, and these change every day. On July 11, there were tornado watches and warnings in Minnesota. The storm system that moved through Minnesota produced 11 reported tornadoes, dime to penny sized hail, and high winds. Damage from the storm included several downed trees, toppled power lines, and even overturned tractors. Click on image for full size (119 Kb) Courtesy of the National Weather Service Office of Grand Forks, ND/Chauncy Schultz

A watch, warning, or advisory is an important way for the National Weather Service of the United States to alert people about hazardous weather. As a community member, it is important to be aware of any watches, warnings, or advisories. What is the difference between the three and what do they mean?

Advisories are notices of weather conditions that are less severe than a watch. If precautions aren’t taken, there is a potential threat to life or property.

A watch signifies there is an increased risk for hazardous weather or hydrological event. It is still unknown if, when, and where the event will take place. A watch may be issued in advance to allow people enough time to prepare for the potential event.

Following a watch is a warning. A warning is issued when the hazardous weather or hydrological event is occurring, will soon occur, or is very likely to occur for that area. A warning means people need to take action because there is threat to life or property.