PORTSMOUTH, Va. (WAVY) – When there’s a chance for storms and they could be strong, the Super Doppler 10 Weather Team shows you a risk map, Levels 1 through 5, with 5 being the highest. The NOAA Storm Prediction Center issues these risks.
To get strong and severe thunderstorms, you need abundant amounts of lift and shear, which allows thunderstorms to tilt with height and be long lived, and finally spin in the atmosphere to support rotation.
Level 1: Marginal. This means a few thunderstorms could become strong that develop in this area.
Level 2: Slight. This is when we have more ingredients for stronger storms. These storms are short lived and usually not widespread.
Level 3: Enhanced. This is when we can see several severe storms within the area. Typically we do not see risks much higher than this in a severe weather season in our region.
Level 4: Moderate. This is when severe weather is expected to be widespread, large tornadoes are possible.
Level 5: High risk. While rare across the United States, we usually see a handful of high risk days across the US every year. When we see a high risk day is when all of the atmospheric ingredients come together to create an explosive atmosphere. Widespread severe is expected on days like this; long lived tornadoes are possible. During the highest level days tornado outbreaks are possible.
Several years ago the Storm Prediction Center expanded to five levels instead of three. This is the same agency that issues severe weather watches. Our local National Weather Service issues the warnings.