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000
NOUS41 KWBC 201952 AAB
PNSWSH

Service Change Notice 17-63 Updated
National Weather Service Headquarters Silver Spring, MD
352 PM EDT Thu Jul 20 2017

To: Subscribers:
 -NOAA Weather Wire Service
 -Emergency Managers Weather Information Network
 -NOAAPORT
 Other NWS Partners and NWS Employees

From: Dave Myrick
 NWS Office of Science and Technology Integration

Subject: Updated: Extra-Tropical Storm Surge (ETSS) model
 upgrade and the first version of Probabilistic
 Extra-Tropical Storm Surge (P-ETSS) model:
 Effective TBD

Updated to change effective date to To Be Determined (TBD) from
August 8, 2017

On TBD, beginning with the 1200 Universal Coordinated Time (UTC)
cycle, the Extra-Tropical Storm Surge (ETSS) model will be
upgraded to:

 A. Create a single basin with overland information that covers
the Gulf of AK and the West Coast
 B. Create a new Tide version to resolve a tidal phase shift in
the Cedar Key (CD2), Tampa Bay (ETP3) and Apalachicola Bay (AP3)
Sea Lake and Overland Surges from Hurricanes (SLOSH) basins.
 C. Remove a wiggle seen in the station guidance from ETSS V2.1
 D. Experimentally generate a maximum storm tide above the
North American Vertical Datum of 1988 (NAVD-88) over the next
102 hours product
 E. Extend the guidance from 96 to 102 hours
 F. Discontinue the dissemination of the 5.0 km CONUS and 6.0
km AK grids
 G. Make general Enhancements / Bug fixes (e.g., make the CSV
files self-describing, add comments to the Standard Hydrologic
Exchange Format (SHEF) output and correct the linear
interpolation methods in the post-processing codes).

Also, on implementation day, the first version of Probabilistic
Extra-Tropical Storm Surge (P-ETSS) will be released.  It will:
 A. Run ETSS 2.2 with the 0.5 degree wind and pressure fields
from the Global Ensemble Forecast System`s (GEFS) 21 members
 B. Equally weight the results to generate the probability
 C. Create products as detailed in the new P-ETSS products
section below:

The following ETSS products are available on the National
Centers for Environmental Prediction (NCEP) dissemination sites:
http://nomads.ncep.noaa.gov/pub/data/nccf/com/etss/prod/
ftp://ftp.ncep.noaa.gov/pub/data/nccf/com/etss/prod/
http://www.ftp.ncep.noaa.gov/data/nccf/com/etss/prod/


Or the NWS National Digital Gridded Database (NDGD)
dissemination sites:
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.s
losh/AR.conus/
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.s
losh/AR.alaska/
http://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.
slosh/AR.conus/
http://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.
slosh/AR.alaska/

1. New ETSS products

- Generation of new maximum storm tide above NAVD-88 over the
next 102 hours products on NCEP servers:
 etss.tHHz.max.stormtide.con2p5km.grib2 for 2.5 km CONUS grid
 etss.tHHz.max.stormtide.con625m.grib2 for 625 m CONUS grid
 etss.tHHz.max.stormtide.ala3km.grib2 for 3.0 km Alaska grid

- The guidance will be extended from 96 to 102 hours on the NCEP
servers for:
 etss.tHHz.stormsurge.con2p5km.grib2
 etss.tHHz.stormtide.con2p5km.grib2
 etss.tHHz.stormsurge.ala3km.grib2
 etss.tHHz.stormtide.con625m.grib2
 etss.tHHz.tide.con625m.grib2
 etss.tHHz.stormsurge.ala3km.grib2
 etss.tHHz.stormtide.ala3km.grib2
 shef.etss.tHHz.totalwater.est
 shef.etss.tHHz.totalwater.gom
 shef.etss.tHHz.totalwater.wst
 shef.etss.tHHz.totalwater.ber
 shef.etss.tHHz.totalwater.goa
    where HH is the cycle hour

- New 2.5 km CONUS and 3.0 km Alaska surge plus tide grid
products on NDGD servers:
 ds.etss-stormtide-2p5.bin
 ds.etss-stormtide-3p0.bin

- New 625 m CONUS surge plus tide and tide only grid products on
NDGD servers:
 ds.etss-stormtide-625m.bin
 ds.etss-tide-625m.bin

2. ETSS Output Changes

- The NDGD directory structure for all ETSS CONUS and Alaska
products will be split into five new folders according to valid
period.  Users will now find the output stripped of super-
headers and routed into the appropriate day 1, day 2, etc. as
defined below:
 VP.001/ (day 1 guidance)
 VP.002/ (day 2 guidance)
 VP.003/ (day 3 guidance)
 VP.004/ (day 4 guidance)
 VP.005-007/ (day 5 through 7 guidance)

- The station text format product and SHEF product for Gulf of
Alaska are contained in a tar file "etss.tHHz.shef_tar" that
will be renamed on the NCEP servers as follows:
etss.tHHz.stormsurge.gok.txt => etss.tHHz.stormsurge.goa.txt
shef.etss.tHHz.totalwater.gok => shef.etss.tHHz.totalwater.goa
   where HH is the cycle hour

- The 2.5 km CONUS and 3.0 km Alaska surge only grid products
will be renamed on the NDGD servers as follows:
ds.etss-2p5.bin => ds.etss-stormsurge-2p5.bin
ds.etss-3p0.bin => ds.etss-stormsurge-3p0.bin

- All GRIB2 encoding was changed to use meters to 3 decimals
instead of 5, which significantly reduces the file size.  No
precision was lost because the actual data is in tenths of a
foot, which can be recovered uniquely from meters with 3
decimals.

- The process ID in the GRIB2 messages was changed from 12 to 16
to allow P-Surge (12), ETSS (16) and P-ETSS (18) to be
differentiated.

- Some station identifiers in the station text format products
(etss.tHHz.PROD.RGN.txt) are changing with this upgrade (e.g.,
CFWM1 CUTLER, ME is now 8411060 CUTLER, ME as we had not
previously associated its Center for Operational Oceanographic
Products and Services (CO-OPS) station ID to it).

- The following files will be created later than in ETSS v2.1,
due to the larger basin size for the West Coast:
 mdlsurge.HHw - 7 minutes delayed
 etss.tHHz.stormsurge.wst.txt - 11 to 12 minutes delayed
 etss.tHHz.stormtide.wst.txt - 11 to 12 minutes delayed

After implementation day, the following new P-ETSS products will
be found on the NCEP web dissemination sites:
http://nomads.ncep.noaa.gov/pub/data/nccf/com/petss/prod/
ftp://ftp.ncep.noaa.gov/pub/data/nccf/com/petss/prod/
http://www.ftp.ncep.noaa.gov/data/nccf/com/petss/prod/


Or the NWS National Digital Gridded Database (NDGD)
dissemination sites:
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.pe
tss/AR.conus/
http://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.p
etss/AR.conus/

The P-ETSS directory structure will match the new ETSS directory
structure.  Files will be placed into the respective folders for
the valid period, such that:
 VP.001/ (day 1 guidance)
 VP.002/ (day 2 guidance)
 VP.003/ (day 3 guidance)
 VP.004/ (day 4 guidance)
 VP.005-007/ (day 5 through 7 guidance)

1. New P-ETSS products

- Station text format storm surge and storm tide products on
NCEP servers:
 petss.tHHz.NAME.stormsurge.RGN.txt
 petss.tHHz.NAME.stormtide.RGN.txt

Where NAME is the product type (e10, e90=storm tide height
exceeded by 10%, 90% of the ensemble members; max, mean and
min=maximum, mean and minimum storm tide heights of the ensemble
members), HH is the cycle hour and RGN is the region (est=East
coast, gom=Gulf of Mx, wst=West coast, ber=New Alaska Basin,
goa=Gulf of AK).

- Above NAVD-88 gridded products on NCEP servers:
A) Incremental hourly groups to hour 102 products for CONUS:
 petss.tHHz.stormtide_NAME_1hr_inc_dat.con2p5km.grib2
 petss.tHHz.stormtide_NAME_1hr_inc_dat.con625m.grib2
B) Incremental hourly groups to hour 102 products for Alaska:
 petss.tYYYYMMDDHHz.stormtide_NAME_1hr_inc_dat.ala3km.grib2
C) Cumulative 6-hourly groups to hour 102 products:
CONUS
 petss.tHHz.stormtide_NAME_6hr_cum_dat.con2p5km.grib2
 petss.tHHz.stormtide_NAME_6hr_cum_dat.con625m.grib2
Alaska
 petss.tHHz.stormtide_NAME_1hr_cum_dat.ala3km.grib2

- Above ground level (AGL) gridded products on NCEP servers:
A) Incremental 6-hourly groups to hour 102 products:
CONUS
 petss.tHHz.stormtide_NAME_6hr_inc_agl.con2p5km.grib2
 petss.tHHz.stormtide_NAME_6hr_inc_agl.con625m.grib2
Alaska
 petss.tHHz.stormtide_NAME_6hr_inc_agl.ala3km.grib2

B) Cumulative 6-hourly groups to hour 102 products:
CONUS
 petss.tHHz.stormtide_NAME_6hr_cum_agl.con2p5km.grib2
 petss.tHHz.stormtide_NAME_6hr_cum_agl.con625m.grib2
Alaska
 petss.tHHz.stormtide_NAME_6hr_cum_agl.ala3km.grib2

Where NAME is the product type (e10, e20, e30, e40, e50,
e90=storm tide height exceeded by 10, 20, 30, 40, 50, 90% of the
ensemble members; max, mean, min=maximum, mean, minimum storm
tide height of the ensemble members; and gt1, gt2, gt3, gt4,
gt5, gt6, gt7, gt8, gt9, gt10, gt13, gt16 ft=Probability of
storm tide height greater than 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
13, 16 feet above NAVD-88) and HH is the cycle hour.

- Output will also be available on the NDGD server. A full
description of the directory/file structure is available here:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/NDGD-PETSS.pdf

NOAAPORT/SBN Changes

1. ETSS Gridded Data Removal

- Once the NWS Advanced Weather Interactive Processing System
(AWIPS) program is ready, the surge only CONUS 5 km and Alaska 6
km will be discontinued because higher resolution 2.5 and 3.0 km
replacement products are available. The surge only CONUS 5 km
and Alaska 6 km World Meteorological Organization (WMO) headers
are as follows:

    WMO Heading Region
    LHU... KNHC NDFD CONUS 5 km surge only grid
    LHR... KNHC NDFD Alaska 6 km surge only grid

The "..." in the WMO heading is replaced by DHH where D is the
day of the forecast (A=Day 0, B=Day 1, ..., F=Day 5) and HH is
the hour of day when the forecast is valid.  A full description
of WMO header combinations per forecast cycle is available here:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/ETSS_removal_header
s.pdf

2. ETSS Gridded Data Additions

- The surge only CONUS 2.5 km and Alaska 3.0 km gridded products
are being extended from 96 hours to 102 hours.Their WMO
headers are as follows:
    WMO Heading       Region
    MHU... KNHC       NDFD CONUS 2.5 km surge only grid
    MHR... KNHC       NDFD Alaska 3.0 km surge only grid

The "..." in the WMO heading is replaced by DHH where D is the
day of the forecast (A=Day 0, B=Day 1, ..., F=Day 5) and HH is
the hour of day when the forecast is valid.  A full description
of WMO header combinations per forecast cycle is available here:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/ETSS_headers1.pdf

- The surge plus tide CONUS 2.5 km and Alaska 3.0 km gridded
products are being added for 0 to 102 hours.  Their WMO headers
are as follows:
    WMO Heading       Region
    MPQ... KNHC       NDFD CONUS 2.5 km surge plus tide grid
    LPQ... KNHC       NDFD Alaska 3.0 km surge plus tide grid

The tide only and surge plus tide CONUS 625 m gridded products
are being added for 0 to 102 hours.  Their WMO headers are as
follows:
    WMO Heading       Region
    MPU... KNHC       NDFD CONUS 625 m surge plus tide grid
    LPU... KNHC       NDFD CONUS 625 m tide only grid

The "..." in the WMO heading is replaced by DHH where D is the
day of the forecast (A=Day 0, B=Day 1, ..., F=Day 5) and HH is
the hour of day when the forecast is valid.  A full description
of the header combinations per forecast cycle is available here:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/ETSS_headers2.pdf

3. P-ETSS Gridded Data Addition

- The following P-ETSS surge plus tide gridded products are
being added for 0 to 102 hours:

A) CONUS 625 m, CONUS 2.5 km and Alaska 3.0 km resolution
cumulative 6-hourly groups for 10%, 20%, 30%, 40%, 50%, and 90%
exceedance above NAVD-88 and AGL
B) CONUS 625 m, CONUS 2.5 km and Alaska 3.0 km resolution
incremental 6-hourly groups for 10%, 20%, 30%, 40%, 50%, and 90%
exceedance AGL
C) CONUS 2.5 km and Alaska 3.0 km resolution incremental hourly
groups for 10%, 50%, and 90% exceedance above NAVD-88
D) CONUS 625 m, CONUS 2.5 km and Alaska 3.0 km resolution
cumulative 6-hourly groups for probability of Surge > 1, 2, 3, 6
and 10 ft above NAVD-88 and AGL
E) CONUS 625 m, CONUS 2.5 km and Alaska 3.0 km resolution
incremental 6-hourly groups for probability of Surge > 1, 2, 3,
6 and 10 ft AGL
F) CONUS 2.5 km and Alaska 3.0 km resolution incremental hourly
groups for probability of Surge > 1, 2, 3, 6 and 10 ft above
NAVD-88
G) CONUS 625 m, CONUS 2.5 km and Alaska 3.0 km resolution
incremental 6-hourly groups of ensemble Min, Mean and Max AGL
H) CONUS 2.5 km and Alaska 3.0 km resolution incremental hourly
groups of ensemble Min, Mean and Max above NAVD-88

Their WMO header scheme is available here:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/P-
ETSS_WMO_Header_Scheme.pdf

A full chart of the header combinations per forecast cycle is
available here:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/P-ETSS_headers.pdf

As part of NCEP`s standard 30-day parallel testing, the updated
products will be available here:

http://para.nomads.ncep.noaa.gov/pub/data/nccf/com/etss/para/
http://para.nomads.ncep.noaa.gov/pub/data/nccf/com/petss/para/

Any questions, comments or requests regarding this
implementation should be directed to the contacts below.  We
will review any feedback and decide whether to proceed.

For changes and additions to the Extra-Tropical Storm Surge
guidance, please contact:

    Arthur Taylor
    Meteorological Development Laboratory
    Phone: 301-427-9444
    E-Mail: Arthur.Taylor@noaa.gov

or
    Huiqing Liu
    Meteorological Development Laboratory
    Phone: 301-427-9464
    E-mail: Huiqing.Liu@noaa.gov

For questions regarding the data flow aspects, please contact:

    Carissa Klemmer
    NCEP/NCO Dataflow Team
    College Park, MD
    301-683-0567
    E-Mail: ncep.list.pmb-dataflow@noaa.gov

NWS Service Change Notices are available here:

  http://www.nws.noaa.gov/os/notif.htm