Weather I'm right of weather I'm wrong

 - May 7, 2008, 9:48 AM

OK, so we all know that no one ever does anything more than talk about the weather. But the folks at the National Weather Service’s aviation branch are doing their best to make sure that when they do talk about the aviation climate, at least the dialogue is as accurate as possible.

Surprisingly, however, according to NWS aviation branch chief Mark Andrews, “Until 15 months ago, we did not have a good handle on how accurate our aviation forecasts really were. There was simply no comprehensive verification process in place.” Thanks to new computer capacity, that verification program does exist today, albeit in the early stages. “Numerical weather modeling uses a comprehensive set of equations and lots of computing capacity to make it run, so we always push the state of the art on computing power.”

Five years ago, the NWS believed it could accurately forecast aviation weather only within an 80- to 160-km grid. That meant if you were flying from Indianapolis to Evansville, then your route forecast was basically a guess. Today, Andrews says, “Our forecasts are accurate down to a 12-kilometer resolution. Within a decade, we’ll see one to two kilometers.” NWS releases 575 terminal-area forecasts four times a day, not to mention amendments to any of these, so the accuracy task can be daunting. “Some of the computer coding just to verify what we’re doing is a real challenge alone,” noted Andrews.

NWS is spending $25 million to advance forecasting science and develop new graphical weather products for pilots, such as the new thunderstorm and icing-analysis systems. But NWS has help, too, since much of the atmospheric data the agency uses arrives via the airlines, whose aircraft regularly transmit wind and temperature information back to the ground for use in forecasts. “We routinely receive about 80,000 airborne observations each day,” Andrews added. NWS believes the future of weather forecasting accuracy lies in more data, information that might be obtained if every aircraft flying in the U.S. were equipped with inexpensive sensors and datalink equipment.