1. Office of Coast Survey Establishing a Community-Based Extratropical Storm Surge and Tide Model for NOAA’s Operational Forecasts for the Atlantic and Gulf Coasts Jesse Feyen, Yuji Funakoshi, and Frank Aikman III (NOS/OCS/CSDL) Andre van der Westhuysen and Hendrik Tolman (NWS/NCEP/EMC) Steven Earle and Chris Caruso Magee (NWS/NCEP/NCO) AMS 93 rd Annual Meeting January 6-10, 2013

2. Office of Coast Survey ESTOFS Overview Purpose –Provide an operational set of forecast guidance for extratropical storm surge that includes tides Note: not designed to accurately model tropical cyclone storm surge due to insufficient resolution and lack of hurricane forcing –Provide surge+tide boundary conditions for NWS’s Nearshore Wave Prediction System (NWPS) Mimics WAVEWATCHIII ® (WW3) set-up –Leverages community-based model ADCIRC

3. Office of Coast Survey ESTOFS: Atlantic Domain ADCIRC East Coast tidal database grid (EC2001) 254,565 nodes Coastal resolution ≈ 3 to 5 km Specifies the tidal forcing at open ocean boundary at 60 o W – Global tidal data inversion model TPXO 6.2

4. Office of Coast Survey Operational Set-up Run cycle –4 times per day at 00z, 06z, 12z, and 18z –Global Forecast System (GFS) forcing: 10 m winds and sea level pressure fields input every 3 hours –Approximately 120 min on 32 dual-core processors Total 7.75 day simulation –Runs a tidal simulation followed by tide+wind forced simulation (so surge signal can be isolated) –6-hr nowcast followed by 180-hr forecast –Time step of 5 seconds

5. Office of Coast Survey ESTOFS Output Delivers three types of water level –Combined Water Level (CWL): Surge + tides –Harmonic Tidal Prediction (HTP): Astronomical tides –Subtidal Water Level (SWL): SWL = CWL – HTP = “surge” Provides both fields (hourly) and points (6 min) Generates output on ADCIRC unstructured grid (NetCDF) and NDFD structured grid (GRIB2) –http://www.ftp.ncep.noaa.gov/data/nccf/com/estofs/prod –http://nomads.ncep.noaa.gov/ –GRIB2 files will be delivered via SBN to AWIPS in 2013 Q3

6. Office of Coast Survey Water Level Fields EC2001 grid (NetCDF)NDFD 2.5 km CONUS grid (GRIB2) PR/VI at 1.25 km

7. Office of Coast Survey Water Level Fields EC2001 grid (NetCDF)NDFD 2.5 km CONUS grid (GRIB2)

8. Office of Coast Survey ESTOFS Hydrographs NWS/MDL has created a mirror of its ET-Surge website to display ESTOFS in the same manner people are used to viewing ETSS http://slosh.nws.noaa.gov/etsurge_ESTOFS/

9. Office of Coast Survey ESTOFS Animations OPC displays CWL (surge with tide) above Mean Sea Level (MSL) http://www.opc.ncep.noaa.gov/estofs/estofs_surge_info.shtml

10. Office of Coast Survey Hindcast Skill Assessment Combined Water Level (CWL) East CoastGulf of Mexico Maine Key West Delaware One year (2009) hindcast evaluated at 48 NOS/CO-OPS water level stations

11. Office of Coast Survey ESTOFS Evaluation: November 2009 “Veteran’s Day Nor’easter” Hindcast Validation – The remnants of Hurricane Ida merged with a coastal low mid November – Max wind gust, 60 mph (27 m/s), was reported along the Delaware coast – SS ranged from app. 1.0 to 1.5 m Compare CO-OPS Observed CWL with ESTOFS and ETSS – 8557380 Lewes, DE – 8575512 Annapolis, MD – 8651370 Duck, NC 8557380 8575512 8651370

12. Office of Coast Survey Hindcast Hydrographs Plot shows ESTOFS CWL (red) against observed CO-OPS water level (black) and NWS’s ETSS + CO-OPS tide prediction (blue).

13. Office of Coast Survey Hindcast Hydrographs Plot shows ESTOFS CWL (red) against observed CO-OPS water level (black) and NWS’s ETSS + CO-OPS tide prediction (blue).

14. Office of Coast Survey Hindcast Hydrographs Plot shows ESTOFS CWL (red) against observed CO-OPS water level (black) and NWS’s ETSS + CO-OPS tide prediction (blue).

15. Office of Coast Survey Superstorm Sandy: GFS Track and Intensity NHC Best GFS 10/27 00Z GFS 10/28 00Z GFS 10/29 00Z 10/29/12 23:00 Hurricane Sandy transitioned to a very large post-tropical storm as it interacted with a trough over the eastern US

16. Office of Coast Survey ESTOFS Hydrograph MHW Shoreline ESTOFS Boundary Kings Point, NY Sandy Hook, NJ Atlantic City, NJ ESTOFS Combined Water Level for one forecast cycle the 3 days leading up to landfall ESTOFS Subtidal Water Level for one forecast cycle the 3 days leading up to landfall

17. Office of Coast Survey ESTOFS Hydrograph MHW Shoreline ESTOFS Boundary Kings Point, NY Sandy Hook, NJ Atlantic City, NJ ESTOFS Combined Water Level for one forecast cycle the 3 days leading up to landfall ESTOFS Subtidal Water Level for one forecast cycle the 3 days leading up to landfall

18. Office of Coast Survey ESTOFS Hydrograph MHW Shoreline ESTOFS Boundary Kings Point, NY Sandy Hook, NJ Atlantic City, NJ ESTOFS Combined Water Level for one forecast cycle the 3 days leading up to landfall ESTOFS Subtidal Water Level for one forecast cycle the 3 days leading up to landfall

19. Office of Coast Survey Comparison of Peak Subtidal Water Levels: Superstorm Sandy ! 8449130 Nantucket Island, MA ! 8452660 Newport, RI ! 8452944 Conimicut Light, RI ! 8454000 Providence, RI ! 8454049 Quonset Point, RI ! 8461490 New London, CT ! 8467150 Bridgeport, CT ! 8510560 Montauk, NY ! 8516945 Kings Point, NY ! 8531680 Sandy Hook, NJ ! 8534720 Atlantic City, NJ ! 8536110 Cape May, NJ ! 8555889 Brandywine Shoal Light, DE ! 8557380 Lewes, DE

20. Office of Coast Survey Future ESTOFS Plans ESTOFS Pacific development began in October for completion FY14 – Provide coverage of West Coast, Gulf of Alaska, Hawaii – Funded via NOS/Coastal Storms Program Experimental testing for Western Alaska – Leveraging USACE grid – WALCC funded partnership to improve domain and add effect of sea ice on surges

21. Office of Coast Survey ESTOFS Development Team NOS/OCS/CSDL/Marine Modeling and Analysis Programs –Jesse Feyen, Yuji Funakoshi, Frank Aikman, Mary Erickson NWS/NCEP/EMC/Marine Modeling and Analysis Branch –Andre van der Westhuysen, Ilya Rivin, Arun Chawla, Avichal Mehra, Hendrik Tolman NWS/NCEP/NCEP Central Operations –Steven Earle, Chris Caruso Magee, Becky Cosgrove, Boi Vong NWS/NCEP/OPC –Joe Sienkiewicz, Robert Daniels

22. Office of Coast Survey