When severe weather threatens, how does the National Weather Service know when to issue a warning? According to Allen County Skywarn Assistant Emergency Coordinator Jay Farlow, the human factor is important.
Although the National Weather Service has radar and other mechanical means of watching the weather, there are blind spots in the system. “There are certain things radar can’t see,” Farlow said.
The Allen County chapter of the Amateur Radio Emergency Service, in collaboration with the Allen County Office of Homeland Security, had scheduled a severe weather detection training seminar for March 28. A different kind of emergency forced hosts to cancel the event. “We canceled this event to help our local healthcare system by helping to stagger transmission of COVID-19,” the Allen County Amateur Radio Emergency Service said on its Facebook page.
The National Weather Service Forecast Office of Northern Indiana is located in Kosciusko County. From this position, their radar system can monitor the weather in 37 counties, including many in northern Indiana, and some in southern Michigan and western Ohio.
“Radar beams do not bend … but the earth curves,” said Farlow. This means that by the time radar beams reach Fort Wayne, those beams are still radiating in a straight line from their starting point and they can be 1,500 feet above the surface of the ground here.
While information from this height is helpful, it is important to understand what is happening below 1,500 feet. “Most tornadoes come from low clouds,” Farlow said.
To make up for the blind spots in the radar scans, human weather spotters are asked to relay information back to the National Weather Service. This is especially important in times of heavy weather.
Farlow gave the example of deciding when to sound a tornado warning. A tornado warning is only issued once an official at the local National Weather Service office pushes the specific button to alert area residents of possible danger. But the Weather Service doesn’t want to give false warnings, especially in “places where radar can’t get low enough,” he noted.
So they use a three-part identification process. If a human weather spotter sends a report of a funnel cloud, then the National Weather Service checks the radar. If there are tornado-possible clouds on the scan, then they also check the atmospheric conditions, to make sure they are right for a tornado to happen. If all three pieces of information mesh, then a tornado warning is issued.
Coordination between the National Weather Service and private citizen weather spotters has been going on for some time. Shortly after the historic 1965 Palm Sunday tornadoes, a weather bureau employee in Toledo, Ohio, suggested having citizen spotters send weather information to the weather bureau. These spotters created a group called Skywarn, and they used amateur radios to relay on-the-ground news.
Farlow, who is an amateur radio operator, explained that amateur radios were the tool of choice especially in the 1960s, because their radio signal could reach farther than a citizens band radio signal and amateur radio signals were less affected by lightning. “(It was the) only private reliable mobile communication,” he said.
Today, amateur radio operators still use their radios to send information to the National Weather Service. But people who are not amateur radio operators can also do spotting work and send in information using cell phones, Facebook or Twitter. Farlow said Twitter allows spotters to include photos of the weather, and that Twitter news can get to the National Weather Service up to a day faster than Facebook messages — something important to note when emergency weather preparedness is on the line.
While the options for sending information have expanded since the 1960s, the goal of being a severe weather spotter has stayed the same. It provides protection, from one neighbor to another, when machines can’t quite cover it all.