FIRST OF ITS KIND
Radar was developed during the period of World War II, in secret, and was a tremendous help detecting enemy airplanes. Many credit it as being an important factor in winning the war. They also found that radar showed where it was raining. After the war, radar started to get used for police (radar guns), civil aviation, marine navigation, and, of course, weather.
The first purely weather radar was developed by the Air Force in 1954, and the "Weather Bureau" (now the National Weather Service) started installing a nationwide network in the late 50s. Those radars lasted until around 1990 before being replaced by Doppler Radars. The Dopplers were upgraded to "Dual-Polarization" starting in 2011.
And now, in 2016 NBC10 has gone to the next level: a mobile, dual-polarization Doppler radar developed exclusively for us. Instead of a network of fixed radars hundreds of miles apart, we can now go right to where the storms are!
WHY IS THIS A BIG DEAL?
As good as Doppler radar is, there are weaknesses. Even the latest technology of Dual-Polarization has weaknesses. The first problem is that the earth is round. Any beam shooting out from radar will go in a straight line. So the farther the radar is from the storm, the higher in the storm the beam will hit.[[388961382,355,142]]
It might show the rain thousands of feet above the ground. Is that rain reaching the ground? They won’t know-if the rain is far enough away from the radar. Is the snow in the clouds up there still snow when it hits the ground? They won’t be able to tell. Has the rotation in the storm worked its’ way to the ground in the form of a tornado? They won’t be able to tell. That’s a big reason why there are so many “false alarms” of tornado warnings that don’t verify.
StormRanger10, by making sure it’s close to the storm, solves those problems-and more. By being close, the radar beam can stay very low in the cloud, making it much more accurate in determining:
Rain vs. snow vs. ice
Whether the rain or snow is reaching the ground
Whether a funnel cloud has reached the ground
And….just how heavy the rain is at the ground
MOST IMPORTANT: THE RADAR "GAP"
Existing National Weather Service radars are pretty far apart. No matter how carefully the NWS was in placing their sites, there were "gaps" where radar coverage is not as good as the rest of the area. Below is a map showing the radar network, plus the "gaps." The areas in green are covered the best. In the yellow areas, the radar beam gets so high that it "shoots over" a lot of the details of a storm. And the radar beam gets even higher in the storm in the area with no colors. I refer to this area as the "gap" between radars. That gap includes much of Chester and Berks Counties. It is a sad irony that the counties in our area with the historically highest tornado risk are Chester and Berks. But if we send StormRanger10 that way, the "gap" is closed.
Some of the towns in the biggest gap (neither yellow nor green -- nothing can be seen below 6000 feet):
Reading, Kutztown, Morgantown, Lyons, Honey Brook, Parkesburg, Coatesville
And in the yellow area (smaller "gap" -- nothing can be seen below 4000 feet):
Allentown, Quakertown, Pennsburg, Boyertown, Pottstown, Limerick, Schwenksville, Royersford, Chester Springs, Valley Forge, Downingtown, Chadds Ford, Kennett Square, Chester Heights, Claymont, Hockessin, Wilmington, Newark, New Castle, Bear, Pennsville, Penns Grove.
The most dangerous tornadoes are the ones higher up in the Enhanced Fujita Scale. No EF-4 or EF-5 has been recorded in any part of our area, but there have been a couple of EF-3s. It’s no coincidence that both Lyons and Limerick are in the gap areas listed above.
So far in 2016, NBC10 First Alert Weather has debuted the revolutionary Neighborhood Forecasts, and now StormRanger10.
And there’s more to come…..
Glenn "Hurricane" Schwartz
Chief Meteorologist, NBC10 Philadelphia