As forecasting models improve, forecasters are able to issue more accurate and timely storm warnings and advisories.
Ex.: Weather forecast from wunderground.com,
February 26, 2010 (2 days before the passage)
"A large 1000 mb low pressure system named "Xynthia" is over the eastern Atlantic, and is expected to rapidly intensify Saturday morning into a meteorological 'bomb' that will bring high winds and flooding rains to Portugal, northern Spain, and western France. The models are coming into better agreement now, and have shifted their position for the storm's maximum intensity eastwards. France is now in the bullseye, and the storm is predicted to be at maximum intensity on Sunday morning when it will be positioned over northwestern France. The storm's powerful cold front will sweep ashore south of the low, bringing sustained winds of 50 - 60 mph (80 - 95 km/hr) to the coast of France's Bay of Biscay, with gusts over hurricane force (120 km/hr). The central pressure at that time will range from 966 mb to 972 mb, according to two of our top computer models, the ECMWF and GFS."