Global Forecast System. The operational numerical weather forecasting model run by NCEP. The GFS superceded the AVN and MRF models, on which it is largely based. Forecast data from the GFS is available out to 180 hours at full resolution and 16 days at a reduced resolution.
11:47 EDT Parts of the Middle East have been blanketed in heavy snow, piling more misery on millions of Syrian refugees who have fled the country's bitter civil war.