August-

1. August- September NSF NOAA NRL NCAR UW UM Shuyi S. Chen Rosenstial School of Marine and Atmospheric Science University of Miami Houze et al. (2006, BAMS)

2. Environment RainbandsInner Core TC Internal Dynmaics and Interaction with Environment • Inner core and rainband internactions • Concentric eyewalls and eyewall replacement cycle • Vertical wind shear • Moisture distribution

3. RAINEXis the first experiment using three-Doppler-aircraft flying in hurricanes. Approach: • Use airborne Doppler radar to observe both eyewall and rainband internal vorticity structures simultaneously • Use intensive dropsondes for thermodynamic environment of hurricane rainbands and eyewall to support both analysis and modeling/forecasting • Use model to determine how the vorticity features evolve and storm intensitychanges

5. ELDORA radar RAINEX Flight Coordination

6. RAINEX Operations

7. Dropsondes Plan--target dropsondes and Doppler

8. Hurricanes investigated in RAINEX Katrina Ophelia Rita

9. High-Resolution Multi-nested Vortex-Following Numerical Models at University of Miami: 15 km • UM/RSMAS Coupled Atmos-Wave-Ocean Model Mini ensemble MM5 and WRF forecasts using GFS, NOGAPS, CMC, and GFDL forecast fields as initial and lateral boundary conditions 5 km 1.6 km

10. Obs NHC Fcst MM5 (1.6km) WRF (1.6km)

11. MM5&WRF Global models NHC Fcst Obs

13. Model forecast of eyewall & rainbandsat 1.6 km resolution Katrina Rita Rain rate

14. Day Day Katrina Rain Wind Distance from vortex center

15. Wind Rain Day Rita Rain Distance from vortex center

16. ELDORA data in Katrina-28 August

17. Concentric Eyewalls RAINEX Flights in Hurricane Rita

18. Unprecedented Concentric eyewalls in Rita

19. dBZ Question: How does the “moat form?” ELDORA data show downward motion between the two eyewalls

20. Dropwinsonde in Moat Region of Ritashow“Eye-like sounding”

21. N43 flight-level wind in Rita Inner outer outer Inner Observed MM5 22 September 2005 Inner Radar Reflectivity outer WRF Eyewall Replacement in Hurricane Rita (2005)

22. Model Moist Pot. Vorticity ELDORA observations of the outer eyewall:Evidence of “filamentation” Vorticity (10-4 s-1)

23. (1.6 km) (1.6 km) Katrina Rita

24. 40 50 60 70 Effect of Environmental Humidity TRMM TMI Total Precipitable Water dry humid Katrina Rita Dots represent sample G-IV dropsonde locations

25. Dropsondes show stronger humidity gradient in eyewall replacement case Storm outer environment Rainbandregion Katrina moist Rita moist Katrina dry Rita dry

26. Conceptual Model of How Moisture Gradient Affecting to Rainband Organizations Weak Gradient in Katrina Strong Gradient in Rita Moist Dry

27. Effect of vertical wind shear on Rita Model 5-day forecast

28. Katrina Ophelia Rita CONCLUSIONS Three important storms observed Innovative satellite based flight control First use of ELDORA in hurricanes Data available via NCAR field catalog Operations and data analysis aided by high-resolution modeling

29. CONCLUSIONS Eyewall replacement--formation of “moat” documented Strong humidity gradient may favor concentric eyewalls ELDORA confirms internal structure of rainband ELDORA shows filamentation of vorticity in secondary eyewall Formation of storm rotation in the convective burst phase Dry air intrusion at midlevels