1. ATCF Requirements, Intensity Consensus Sea Heights Consistent with NHC Forecasts (Progress Report) Presenter Buck Sampson (NRL Monterey) Investigators Ann Schrader, Efren Serra (SAIC, Monterey) Paul Wittmann (FNMOC) Hendrik Tolman (NCEP) Mike Frost (NRL, Monterey) Collaborators Chris Sisko, Chris Lauer, Jessica Schauer (NHC) Andrea Schumacher, John Knaff and Mark DeMaria (CIRA) IHC 2011 Miami

2. Tasks 1. NHC User Requirements for ATCF (80% Complete) 2. Intensity Consensus (Complete) 3. Sea Heights Consistent with NHC Forecasts (80% Complete)

3. 1.User Requirements for ATCF Highlights -ATCF Requirements Lists (FY 2010 and 2011) -60 hr forecasts -Capability to save TWO disturbance probabilities -Expanded seas radii capability (>995 nm) -Other NHC/JHT/HFIP Requests -GPCE version of wind probabilities -“Display Only” version of Web-ATCF -Large ensemble ingest, retention and display -ATCF Documentation

4. Sixty Hour Forecast Capability Intensity Track Wind Radii

5. Capability to save TWO disturbance probabilities Transition disturbance to a storm TWO disturbance entry

6. Disabled Menu Items Web-ATCF “Display Only” Mode Disabled functions throughout application. Allows no advisories, no communication with web pages, no storm file updates. Near real-time updates on live tropical cyclones.

7. Large ensemble ingest, storage, display 1000 MC Wind Probability realizations. ATCF can now handle up to 1300 aids for a single date. Still needs color for intensity.

8. Online Documentation ATCF Users Manual (300 pages) ATCF System Administrators Guide (50 pages) ATCF Installation Guide (10 pages) ATCF Storm Archive Management (2 pages) ATCF Objective Best Track Guide (5 pages) fasDB (GRIB and Bufr Database) Guide (25 pages) ATCF Storm Database Format (20 pages) GUI documentation (1000 pages) 22 ATCF related journal articles Link to documents: http://www.nrlmry.navy.mil/atcf_web/docs/ATCF-FAQ.htmlhttp://www.nrlmry.navy.mil/atcf_web/docs/ATCF-FAQ.html

9. 2. Intensity Consensus Forecasts are all “early models” Consensus is average forecast 2006: INT3 = DSHP + GHMI + GFNI 2007: INT4 = DSHP + GHMI + GFNI + LGEM 2008: IVCN = DSHP+ GHMI + GFNI + LGEM + HWFI ICON = DSHP+ LGEM + GHMI + HWFI * As of 2008, NHC names consensus and defines input guidance. More info: Sampson, C. R., J. L. Franklin, J. L., J. A. Knaff and M. DeMaria, 2007: Experiments with a simple tropical cyclone intensity consensus. Wea. And Forecasting, 23, 304-312.

10. Intensity Skill Relative to 2006 NHC Intensity Consensus Atlantic 2009-2010 (507) (385) (294) (234) (DSHP+GHMI+GFNI+LGEM +COAMPS-TC) provided most skill relative to 2006 Intensity Consensus (DSHP+GHMI+GFNI). COAMPS-TC forecasts real-time at NRL in 2010. 2009 reruns courtesy of Yi Jin (NRL). Evaluation does not contain landfall.

11. Intensity Skill Relative to 2006 NHC Intensity Consensus Atlantic 2009-2010 (507) (385) (294) (234) (DSHP+GHMI+GFNI+LGEM +COAMPS-TC) provided most skill relative to 2006 Intensity Consensus (DSHP+GHMI+GFNI). COAMPS-TC forecasts real-time at NRL in 2010. 2009 reruns courtesy of Yi Jin (NRL). Evaluation does not contain landfall. Significant Improvement of 3-4% Over IVCN!

12. 3. Sea Heights Consistent with Official Forecast (OFCL/WW3) 1.Obtain GFS sfc winds 2.Cut out model vortex 3.Generate OFCL vortex 4.Insert OFCL in GFS sfc winds 5.Run WW3 6.Similar in concept to NAH WW3 (Modified) Goals for 2010: Algorithm: 1.Produce grib files for NAWIPS 2.Use 6-h old GFS run to reduce latency 3.Run real-time at NRL 4.ATCF output for 12-ft seas radii

13. 3. Sea Heights Consistent with Official Forecast (OFCL/WW3) 1.Obtain GFS sfc winds 2.Cut out model vortex 3.Generate OFCL vortex 4.Insert OFCL in GFS sfc winds 5.Run WW3 6.Similar in concept to NAH WW3 (Modified) Goals for 2010: Algorithm: 1.Produce grib files for NAWIPS 2.Use 6-h old GFS run to reduce latency 3.Run real-time at NRL 4.ATCF output for 12-ft seas radii

14. OFCL/WW3 OFCL/WW3 Hindcasts vs Buoys TAFB Eval: OFCL/WW3 sea heights 5-6ft low (ouch!)

15. OFCL/WW3 Radii of 12-ft Seas Evaluation Using TAFB Analysis as Ground Truth Improved biases Need to revisit wind radii assignment beyond 72 h as some expansion of wind radii needed (use DRCL?). Also possibly removing too much of background winds during vortex insertion.

16. 3. Sea Heights Consistent with Official Forecast (OFCL/WW3) Remaining Tasks for 2011: 1.Implement in NHC environment (underway) 2.Documentation (underway) 3.Real-time runs in NHC environment in 2011 4.Experiments with modified algorithms (if time permits)

17. Progress Summary 1. NHC User Requirements for ATCF (80% complete) 2. Intensity Consensus Review and Update (complete) 3. Sea Heights Consistent with NHC Forecasts (80% complete)

18. EXPERIMENTAL TC-COR GUIDANCE SITE TC-COR Agrihan 2 Alamagan 2 Anatahan 2 Pagan 2 Saipan 3 Tinian 4 Based on Watches/Warnings and cumulative wind probabilities in the Atlantic and Gulf of Mexico (CIRA) Strategic objective guidance for onset of 50-kt winds at military installations Does not include local effects or base sensitivities TC-COR Threshold ProbabilitiesForecast Lead 4 5% 72 H 3 6% 48 H 2 8% 24 H 1 12% 12 H (NRL, CIRA, NOAA/NESDIS)

19. EXPERIMENTAL TC-COR GUIDANCE SITE TC-COR Agrihan 2 Alamagan 2 Anatahan 2 Pagan 2 Saipan 3 Tinian 4 Based Watches/Warnings and cumulative wind probabilities in the Atlantic and Gulf of Mexico (CIRA) Strategic objective guidance for onset of 50-kt winds at military installations Does not include local effects or base sensitivities TC-COR Threshold ProbabilitiesForecast Lead 4 5% 72 H 3 6% 48 H 2 8% 24 H 1 12% 12 H (NRL, CIRA, NOAA/NESDIS) Why so low?

20. Why are the TC-COR guidance thresholds so low? Guidance should step through conditions sequentially Times should correspond to those in operations, if possible Shouldn’t miss a wind event Objective TC-COR Settings for 26W 2004 at Yokosuka Current ThresholdsDouble Current Thresholds Quadruple Current Thresholds (Maximum Threat Scores) 4 (-70 hours)4 Missed 3 (-34 hours) 3 Missed 2 (-16 hours)2 Missed 1 (-10 hours) 55 kt (Oct 9 1634)

21. Why are the TC-COR guidance thresholds so low? Guidance steps through conditions sequentially Times are reasonable This guidance was *not* available to forecasters in real- time Objective TC-COR Settings for 26W 2004 at Yokosuka Current ThresholdsDouble Current Thresholds Quadruple Current Thresholds (Maximum Threat Scores) 4 (-70 hours)4 Missed 3 (-34 hours) 3 Missed 2 (-16 hours)2 Missed 1 (-10 hours) 55 kt (Oct 9 1634)

22. TC-COR 1 EVALUATION 82 cases 10 Navy and Air Force bases WestPac, Atlantic 1996-2009 TC-COR 1 Forecast vs Base Setting (73 Cases) Observed Yes Observed No Forecast Yes1015 Forecast No057 Observed Yes Observed No Forecast Yes20 3 Forecast No941 TC-COR 1 Forecast vs Observed Wind Near Site (82 Cases) Misses False Alarms Threat Score=.625 Threat Score=.4