Emergency　path　planning　technology　is　one　of　the　hot　research　points　in　intelligent　transportation　systems.　There　are　many　methodologies　and　applications　in　emergency　path　planning.　However,　due　to　the　complexity　of　the　urban　network　and　crowded　road　conditions,　the　difficulty　of　emergency　path　planning.　The　objective　of　emergency　path　planning　is　to　get　the　vehicle　out　of　the　emergency　areas　and　to　its　destination　in　the　shortest　time.　Road　congestion　caused　by　emergency　situations　in　cities　directly　affects　the　original　road　network　structure.　Then　the　weight　of　the　original　road　network　is　no　longer　suitable　as　a　basis　for　path　recommendation　and　the　value　of　edges　of　weight　will　change　over　time.　To　handle　the　dynamic　road　network,　a　novel　situational　time-stamp　heuristic　search　algorithm　(STH)　is　introduced　for　the　situation　space.　This　algorithm　can　effectively　solve　the　problem　of　diversity　of　situational　networks.　STH　can　build　a　heuristic　that　adapts　to　time　changes　based　on　the　map　refresh　time,　and　ensures　that　the　path　given　in　the　time　window　T　is　optimal.　Moreover,　STH　can　give　a　pruning　strategy　according　to　the　search　time　window　T,　which　significantly　improves　the　efficiency　of　the　algorithm.　Finally,　the　path　planned　by　STH　is　better　than　the　baseline　algorithm.　©　Published　under　licence　by　IOP　Publishing　Ltd.