New Hurricane Model Can More Accurately Predict Storm Path, Intensity
Surfersvillage Global Surf News, 26 February, 2014 - When Hurricane Sandy slammed into southern New Jersey in October 2012, it had essentially confounded both the NOAA‘s Global Forecast System (GFS) and the European Centre for Medium-Range Weather Forecasts (ECMWF).
Now, a new real-time hurricane analysis system being developed at Penn State University has been shown to accurately predict the track and intensity of the deadly storm.
“For this particular study aircraft-based Doppler radar information was ingested into the system,” said Fuqing Zhang, a professor of meteorology at Penn State. “Our predictions were comparable to or better than those made by operational global models.”
In addition to incorporating real-time Doppler radar information, the convection-permitting hurricane analysis and forecasting system (WRF-EnKF) also uses high-resolution cloud-permitting grids, which allow for the consideration of individual clouds in modeling a storm system.
“Our model predicted storm paths with 100 km — 50 mile — accuracy four to five days ahead of landfall for Hurricane Sandy,” Zhang said. “We also had accurate predictions of Sandy’s intensity.”
The new model runs 60 storm forecasts simultaneously as a collection, each with differing starting conditions. To evaluate the Hurricane Sandy forecast information, the scientists separated the 60 simulations into three groups: good, fair and poor.
This was designed to segregate uncertainties in the model primary conditions. Zhang said that errors occur because of variances in the primary steering-level winds in the tropics that Sandy was baked into, instead of a mid-latitude trough – an area of reasonably low atmospheric pressure – ahead of Sandy’s path.