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It’s the cool thing to do to pick on your local TV weatherperson. If he or she gets the forecast right, nobody thinks twice about it. However, if your local meteorologist gets the forecast wrong, it opens the floodgates for taunting and even vitriolic ranting on the part of unhappy viewers. Broadcast meteorologists are arguably the most visible scientists in the world, but few people understand just how much they do, or the technology behind the local weather report.

Your friendly local weatherperson is probably an “actual” meteorologist

Gone are the days when television stations hired an attractive face to present prepackaged weather forecasts from the National Weather Service, for the most part. From the largest markets to the smallest, a substantial number of TV meteorologists hold some kind of degree in meteorology. Television stations pride themselves on their weather teams, who provide viewers with not only the day to day forecast, but crucial, life-saving safety information during severe weather.

Seals of approval give the audience a way to determine the credibility of a TV meteorologist. One of the most visible ways TV mets are able to build trust with their audience is to display their seals on-screen next to their name. These seals either read “AMS” or “NWA.”  The AMS Seal of Approval comes from the American Meteorological Society, an academic association of more than 14,000 meteorologists, and the NWA seal comes from the National Weather Association. Each seal is attained through a process that judges the seal holder’s knowledge of meteorology and ability to convey weather information in an effective manner.

Even if your weatherperson doesn’t hold a degree in meteorology, he or she probably has enough education through experience to cover weather in the local area. In addition to experience, several respected universities offer certificates in broadcast meteorology, which is a track pursued by many TV journalists who hold degrees in other fields.

Forecasts are made in-house

Broadcast meteorologists don’t crib their forecasts from the National Weather Service or The Weather Channel or anyone else — most of their forecasts are created in-house. This is why you might notice a discrepancy in forecasts from station to station. The effect is most pronounced during an impending snowstorm. During any storm, one could flip through the four major networks in D.C. and see NBC call for two to five inches of snow, FOX calling for three to six, WJLA predicting one to three, and WUSA expecting just a dusting.

The only common forecasts that the stations themselves don’t create are severe weather outlooks that come from the Storm Prediction Center, and hurricane forecasts from the National Hurricane Center.

Many stations have their own radars

The anchor of any severe weather coverage is radar imagery. In addition to using the feed from the National Weather Service’s network of Doppler weather radars, some television stations actually have their own radars. These radars are usually smaller and less powerful than the ones utilized by the NWS, but they work well enough for news stations to keep track of storms.

A well-known, easily viewed news station radar sites is WYFF’s radar sitting off the west side of I-85 near Anderson, South Carolina (pictured above). Fox 13 in Tampa, Florida is another station that prides itself on its in-house weather radar, which sits atop a large column at the station’s studio.

The radar competition is so intense that even Jon Stewart had to comment on the “weather wars” back in 2006 when a news station in Terre Haute, Indiana released a political-like slam ad on one of its broadcast competitors for having a less-experienced weather team and a poorly-placed Doppler radar.

Speaking of radar: The radar sweep is fake

In the middle of the dark colors and couplets and flashing animated bolts of lightning is a thick, white radar beam sweeping across the map. The beam gives the illusion that the radar is updating with almost real-time frequency, but it’s just that: an illusion.

Doppler weather radar updates every four or five minutes on average, but with recent software upgrades (one of which is SAILS), we can have fresh low-level radar images almost every two minutes. The animated beam we see on television broadcasts is just for show, leading viewers to believe that the radar image is updating more often than it really is.

(In a response to this blog, WRAL meteorologist Nate Johnson said that for those stations with their own radars, the sweep is indeed real!)

Your local meteorologist’s storm coverage saves lives

The Federal Communications Commission gives television stations a license to broadcast based on the understanding that they exist in order to serve the public interest. For a local news station, there is no greater public service than providing severe weather coverage to their viewers. Most (if not all) news stations have a policy that requires their meteorologists to break into any programming if a tornado warning is issued within their viewing area.

It’s possible that when meteorologists have to break into scheduled programming, it’s during a popular show, like American Idol or the World Cup. The solid majority of viewers who live outside of the tornado warnings usually don’t appreciate the interruption and some send meteorologists awful messages to vent their displeasure, even including death threats.

If a meteorologist interrupts programming to cover severe weather, viewers have no right to complain. News stations exist to serve the public interest, and the public interest will always lean towards safety rather than entertainment.

Broadcast meteorologists and local television weather reports are widely used and greatly underappreciated. The next time you flip on the weather report, think about how much time and effort went into their forecasts. There’s more to it than meets the eye; it isn’t just regurgitating model data or reading someone else’s forecast off of a teleprompter.