Temporal Oscillations of Pressure and Wind Speed in a Windstorm over Complex Terrain

The winds and pressure fields are analyzed during a windstorm over East Iceland on 17-18 February 2003. The maximum wind speeds in the windstorm are found to be associated with a small scale anomaly in the surface pressure field. The anomaly is about 3 hPa and travels upstream with the speed of 20 km/hr. A numerical high-resolution simulation reproduces a similar but weaker feature. The study indicates that the pressure anomaly is a result of a vertically propagating gravity wave generated by the interaction of the flow and the orography.