1. Naomi Surgi and HWRF Team Naomi Surgi and HWRF Team NCEP/Environmental Modeling Center WHERE AMERICA’S CLIMATE AND WEATHER SERVICES BEGIN ™

2. HWRF TEAM Bob T., Qingfu L., Vijay T., Young K., Janna O’C, Zack Z. A lso, Many thanks to Isaac G. & URI Morris B……

3. Overview HWRF ’07 implementation strategy, initial HWRF config, T&E requirements 2007 HWRF 2008 implementation Advancement of HWRF GFS, Waves

4. HWRF Development  CONDUCTED 27 EXPERIMENTS since 2002, ie: 27 versions of the HWRF  Tested each upgrade (numerics, physics, coupling) for clean comparisons - comprehensive testing (>200 runs)  FINALIZED HWRF FOR ‘07  PERFORMED EXTENSIVE COMPARISONS BETWEEN GFDL AND HWRF FOR MULTIPLE SEASONS AND STORMS - THREE SEASONS (‘04, ’05, ’06) for both ATL and EPAC basins Note: HWRF, 1745 runs; GFDL 900 runs; HWRF ran 4X/day, GFDL 2X/day. Ran homogeneous comparison between HWRF and GFDL for 0Z and 12Z runs  NO TUNING OF HWRF (tuning has a lot of impact on track and intensity skill)  NO OCEAN COUPLING IN EPAC

5. Hurricane Forecast System Requirements Document for T20 Requirements document co-written between EMC and TPC for transition to NCEP operations of a new candidate hurricane model…or for annual or periodic upgrades to an existing operational hurricane model for transition to NCEP operations. Sets standards for: Performance testing – case load, eval criteria Performance testing – case load, eval criteria System functionality – initialization, coupling System functionality – initialization, coupling Computational performance Computational performance

6. THE HWRF SYSTEM (Initial Operating Capability) 2007 Movable, 2- way nested grid (9km; 27km/42L; ~75X75) Advanced Physics (GFS&GFDL) Advanced vortex initialization – made use of prototype GSI 3D var (advancement over bogus) POM ocean (w/loop current init – same as GFDL)

7. 2007 HURRICANE SEASON

10. HWRF GFDL Hurricane Dean August 11–22, 2007

11. Tropical Storm 08/16 00Z Cat. 1 Cat. 2 Cat. 3 08/17 12Z 08/18 00Z Cat. 4 Cat. 5 Cat. 4 Cat. 5 08/20 18Z 08/21 06Z Cat. 5 Cat. 1 08/22 18Z Cat. 2 08/20 18Z 08/22 18Z 90 kts Cat. 2 139 kts Cat. 5 TS Cat 1 Cat 2 Cat 3 Cat 4 Cat 5 Hurricane Dean 5 day forecasts of maximum winds starting from 8/19/06Z 08/19 06Z

12. HWRF GFDL Hurricane Felix Aug. 28–Sep. 05, 2007

13. HWRFGFDL Hurricane Humberto September 12-13, 2007

14. HWRFGFDL Hurricane Noel October 25-November 02, 2007

15. EPAC

16. HWRF Track

17. Tropical Storm Kiko July 14 – 24, 2007 GFDL HWRF GFDL

18. TS KIKO

19. TS BARBARA HWRF HWRF HWRF

20. Hurricane Henriette GFDL Nearly a perfect forecast…..

21.   UPGRADE HURRICANE INITIALIZATION   UPGRADE PHYSICS T&E – rerun ‘05 and Aug/Sept. 07 To run In parallel: Vortex initialization w/assimilation of airborne doppler radar obs HWRF + HYCOM + WAVEWATCH 2008 IMPLEMENTATION

22. WAVEWATCH III –Coupled HWRF-HYCOM-WAVEWATCH model system. HWRF-HYCOM parallel runs 2008 hurricane season, test with adding WAVEWATCH late FY2008. WAVEWATCH w/ relocating inner HWRF nest only. Coupling based on Hara’s stress parameterization. –Developing two-way nested WAVEWATCH with relocatable nest for expanded coupling (2008-2009). –Expand (shallow water) physics (2009 and beyond). 5

23. WAVEWATCH III 2 Resolution in minutes of the 8 grids making up the multi-grid model

24. WAVEWATCH III 3 old WNA model new multi-grid model including surf zone physics Katrina

25. GFS/Proposed data assimilation and model changes  FOTO (First-Order Time-extrapolation to Observations- simplified 4-D var),  Situation dependent variances  Improvements in physics, treatment of clouds  Mountain blocking, gravity waves  Improved analyses in global tropics  Improved GFS track skill

26. 2008-2012 HURRICANE UPGRADE PLAN   Data assimilation: Continuous upgrades to HWRF hurricane core initialization through advanced 4-D data assimilation for winds and reflectivity (requires nearly continuous obs for hurricane structure from storm top to surface beginning in depression stages through evolution of storm lifecycle). Augment doppler data with GPS sondes. Also, explore use of satellite microwave data. UAV’s?   Model upgrades: Increase resolution – 4-6km/64-100L. Hurricane Ensembles for structure/intensity: Hi-res hurricane multi-model ensembles, e.g. HWRF, GFDL, NAM, GFDN, COAMPS? Work underway

27.   Model Physics: Continuous upgrades to atm/ocean boundary layer, microphysics/deep convection (cloud resolving scales?), radiation   Advance Wave Model (WAVEWATCH III) to forecast waves up to the beach, ie: improve non-linear interactions, surf zone shallow water physics, wave interactions with currents   Coupling to land surface model w/ adv. Sfc. Physics for improved rainfall forecasts at landfall. Important input to hydrology and streamflow models to address inland flooding. ALL hurricane model physics upgrades dependent on allowable resolution, e.g. affordable complexity of microphysics, sea spray, explicit representation of all clouds.

28. 08 09 10 11 12 Radial velocities Advance reflectivity - 4DVAR Mesoscale Data Assimilation for Hurricane Core Advancing HURRICANE WRF System Atm. Model physics and resolution upgrades (continuous) Atm/ocean boundary layer: wave drag, enthalpy fluxes Atm/ocean boundary layer: wave drag, enthalpy fluxes Microphysics, radiation Microphysics, radiation Incr. Res: 4-6km/100L? Incr. Res: 4-6km/100L? Land surface Coupling Land surface Coupling Waves: multi-grid/surf-zone physics Ocean: 4km. - continuous upgrades in Ocean Data Assimilation. HWRF Ensembles SS SS

29. Hurricane-Wave-Ocean-Surge-Inundation Coupled Models High resolution Coastal, Bay & Estuarine hydrodynamic model Atmosphere/oceanic Boundary Layer HYCOM 3D ocean circulation model WAVEWATCH III Spectral wave model NOAH LSM NOS land and coastal waters NCEP/ Environmental Modeling Center Atmosphere- Ocean-Wave-Land runoff fluxes wave fluxes wave spectra winds air temp. SST currents elevations currents 3D salinities temperatures other fluxes surge inundation radiative fluxes HWRF SYSTEM NMM hurricane atmosphere HWRF/multi-model hi-res ensembles (2013) for adv. storm surge model

30. HWRF and the community HWRF code available to community w/op imp 1 st DTC HWRF tutorial – 2009? (resources permitting) HWRF team establishing many working collaborations, e.g. URI, FSU, CSU, Univ. of Hawaii, PSU, NRL, UKMO, JMA

31. NOAA’s Aircraft in Hurricanes Working on flight strategies for GIV and P-3’s Operational requirement for core data at 0Z, 12Z to initialize HWRF core circulation (06,18Z ?) Two mission profiles: Environment & CORE Observations: GPS, Radar, AXBT’s THANKS TO AOC AND HRD

32. THANK YOU FOR YOUR ATTENTION…

33. Research model forecasts of storm intensity for Hurricane Katrina showing benefit of high (1.6 km) resolution High-res models (1.6km) NHC Forecast Obs Katrina Landfall GFDL model Global models

34. High-res models (1.6km) NHC Forecast Obs Katrina Landfall GFDL model Global models Research model forecasts of storm intensity for Hurricane Katrina showing benefit of high (1.6km) resolution (S. Chen) Intensity Forecast of HurricaneKatrina 0000 UTC 27 August 2005 HWRF model HWRF

35. IN FACT: From 114 hrs to 60 hrs before landfall, seven HWRF forecasts predicted rapid intensification of Hurricane Katrina, predicting Category 5 Hurricane Three HWRF forecasts predicted Category 3 landfall for Hurricane Katrina Three HWRF forecasts of max. intensity coincided with observed maximum intensity

36. Katrina Landfall HWRF Max. Intensity: 147 kts Obs Max. Intensity: 150 kts

37. HWRF Max. Intensity: 144 kts Katrina Landfall Obs Max. Intensity: 150 kts

38. HWRF Max. Intensity: 138 kts Katrina Landfall Obs Max. Intensity: 150 kts

39. HWRF Max. Intensity: 140 kts Katrina Landfall Obs Max. Intensity: 150 kts

40. HWRF Max. Intensity: 156 kts Katrina Landfall Obs Max. Intensity: 150 kts

41. HWRF Max. Intensity: 150 kts Katrina Landfall Obs Max. Intensity: 150 kts

42. HWRF Max. Intensity: 154 kts Katrina Landfall Obs Max. Intensity: 150 kts

43. Hurricane Initialization in HWRF model Regional GSI analysis cycle (3D VAR) 9 hours forecast at time t-3, t, t+3 GSI analysis at time t-6 Relocate the modified hurricane vortex GSI analysis at time t 3 or more days forecast t  t+6

44. Hurricane vortex modification –Intensity correction –Better balanced wind, temperature and pressure fields –Storm depth correction –Moisture and hydrometeor correction GSI analysis –Airborne radar data (parallel run)

45. FOTO (formerly called Simplified 4d-Var) At no additional cost includes: –Includes time extrapolation to observation using slow modes –Improves fit to obs –Some slowing of convergence

46. Obs - Background Analysis 3D-VAR Difference from Background Forecast Updated Forecast T = 0T + 3T - 3 Time

47. Obs - Background Analysis FOTO Difference from Background Forecast Updated Forecast T = 0T + 3T - 3 Time

48. Situation dependent background variances Variances modified based on 9hr-3hr differences –Increased in rapidly changing locations –Decreased in others (global mean preserved) No additional cost

49. NOAA’s Aircraft in Hurricanes Working on flight strategies for GIV and P-3’s Working to obtain resources for flight hrs/add’l crews Operational requirement for core data at 0Z, 12Z to initialize HWRF core circulation (06,18Z ?) Operational requirement for AXBT’s Two mission profiles: Environment & CORE Observations: GPS, Radar, AXBT’s New operational status of P-3’s

50. operational parallel operational parallel