Web Exclusive - July 2019
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Make Better Weather Decisions

By Dan Gallagher

Reading the Radar Display: What to Remember

Understanding the history of radar technology and knowing the source of the radar display can prepare anyone to better utilize radar information. Conscientious administrators and officials can recall these radar facts as part of their decision-making process when referencing radar data:

  • Radar cannot see everything. As apparent in the Buffalo snowfall example, the physical limitations of radar mean that a radar does not "see" what occurs close to the ground. Additionally, since what radar "sees" in the atmosphere is affected by distance as the beam of energy continues to radiate away from the source, the precision of data can depend on the location of weather relative to the location of a radar. Some radar displays are compilations of data from multiple radars, and these multiple radar displays are often pieced together to account for gaps in radar coverage.
  • No one image tells the whole story. Weather evolves in stages, so it is important to watch storm motion, growth and decay. When watching weather on radar, how it trends from one scan to the next should never be ignored. Evaluating trends allows watchers to better predict turbulent weather. Then, for the best results, avoid focusing on only one storm. People tend to watch a particular storm and not the entire picture, or what is downstream of the "worst" storm. This can distract from impactful conditions and trends.
  • Raw data can be misleading. Even when radar "sees" weather accurately, it can at times mislead watchers. Virga, for example, is precipitation that evaporates before it reaches the ground due to drier air closer to the surface. Just because the radar shows precipitation does not always mean precipitation will reach the ground. In some cases, there is no substitute for using other information to determine what is actually happening. That is why NEXRAD/Baron delivers more than just a radar image to give users a better understanding of what the weather is doing. It gives information on severe winds, threats, velocity, hail tracks and other conditions.

Baron Threat Net is used by stadiums, emergency management, schools, racetracks and other institutions because it features radar technology that makes it easier for users to identify what the risk is by removing all of the extraneous information and processing inevitable problems in the data to create a simplified picture of the weather. However, to do that, it uses computing power, scientific expertise, and other tools. Radar should not be solely relied upon to identify every weather phenomenon. It is important that decision-makers understand the limitations of the technologies they utilize in order to not only make the best decisions for their communities, but to reinforce community trust.

Dan Gallagher is enterprise product manager for Baron.