The flight rerouting is an important measure of relieving flight delays causeded by severe weather. This paper confirmsSreroutingSroute atSthe sameSlevel through designing the heuristic algorithm, in view of shrinkageSsevere areas according to a certain speed.Firstly, this paper sets the initial rerouting point according to severe areas the time when airplane is flying over the starting point of rerouting, considers severe areas are shrinking continuously during airplane has been flying, obtains the intermediate rerouting point through the first phase of dynamic model of rerouting,and then obtains the finally rerouting point through the second phase of dynamic model of rerouting, the model makes airplane round dynamic severe areas as short as possible, and reduces delayStime. Finally,Sthis paper verifiesSthe reasonability of the model and algorithm through the simulation analysis of existing routes from Guiyang to Changsha.