The National Weather Service upgraded its forecast model, with an eye on predicting extreme weather events better and faster
By including much higher layers of the atmosphere, increased factoring of ocean waves and other improvements, the weather service’s update to its Global Forecast System is trying to catch up with a European weather model that many experts consider superior.
Forecasters say this new model does not predict more rain and snow than actually arrives, which its predecessor had a tendency to do. The new model was significantly better at forecasting the massive Colorado snowstorm earlier this month, getting the storm arrival time and snow amounts far more accurately than the older version, said Vijay Tallapragada, chief of modeling at the agency’s Environmental Modeling Center.
“This is for the general day-to-day forecasting and for the extreme events, and you’ve got to get both right,” said National Weather Service Director Louis Uccellini.
One main improvement is that the new model captures the atmosphere up to 50 miles high (80 kilometers) — far higher than the old one and has higher resolution at different levels, weather service officials said. This way it better characterizes the jet stream, which transports storms, they said.
Over the past 31 days, there was a stretch of eight straight days when this new version beat the highly-touted European forecast model, but in general over the period the European version was still better, Uccellini said.
“Extreme weather events are becoming stronger and happening more often in a changing climate,” said Bernadette Woods Placky, chief meteorologist at Climate Central’s Climate Matters program, who wasn’t part of the upgrade. “Weather forecasting improvements that increase accuracy and warning time will give people more time to prepare and will save lives.”
Follow Seth Borenstein on Twitter at @borenbears.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.