Observations of the structure and evolution of Hurricane Edouard (2014) during intensity change: Kinematic structure and the distribution of deep convection

This presentation examines airborne observations of the inner-core and near environmental structure and evolution of Hurricane Edouard during two days of its lifecycle: one when there was a significant intensification as Edouard approached hurricane status on 14 September and the second, two days later, when Edouard had reached peak intensity and was beginning to weaken. Edouard showed distinct differences in the temporal and spatial distribution of deep convection for these two periods. During the intensifying period, deep convection (echo tops above 16 km and upper-level updrafts > 5 m s-1) was noted in both the downshear left and upshear left quadrants. This convection is traced to strong updrafts that were present in the downshear right quadrant inside the radius of maximum winds, collocated with strong convergence in the lowest 2 km. Strong updrafts persisted upshear left, where they were collocated with high inertial stability from the inner core. During the weakening period, no deep convection was present, and the precipitation that was observed was associated with weaker convergence downshear right that was located at and outside the radius of maximum winds. Weak updrafts were seen upshear left, with little coincidence with the high inertial stability region of the inner core on this day. Some potential reasons for the differences in these spatial and temporal distributions of deep convection, including kinematic structures shown here and thermodynamic structures shown in the companion talk by Zawislak et al., are investigated here.