The numerical weather prediction (NWP) products aiming to severe weather prediction, including T639, GRAPES_RUC,WRFEPS, were developed by Numerical Weather Prediction Division, NMC. Through the analysis of the squall line weather occurring in Henan Province on 3 June, 2009, it is showed that the high resolution models have improved to some extent forecasting severe weather. But the 15 km resolution is not so good enough to forecast severe weather. Higher temporal and spatial resolution is needed to better reveal the evolation of severe convection weather in the application of the NWP products.