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000
NOUS41 KWBC 221540
PNSWSH

Service Change Notice 17-106
National Weather Service Headquarters Silver Spring, MD
1140 AM EDT Fri Sep 22 2017

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

From:  Dave Myrick
  NWS Office of Science and Technology Integration

Subject:  Upgrade to High Resolution Ensemble Forecast (HREF)
  and High-Resolution Window (HIRESW) Effective
  November 1, 2017

Effective on or about November 1, 2017, beginning with the 1200
Coordinated Universal Time (UTC) run, the National Centers for
Environmental Prediction (NCEP) will upgrade the HREF and HIRESW
systems to makes changes to:

 - HREF model membership
 - HIRESW model runs, including changes to initialization and
earlier product availability
 - Output products in HREF and HIRESW, including NOAAPORT

1) Changes to the HREF model membership

For the CONUS domain:

 - Adds a second Weather Research and Forecasting (WRF)
Advanced Research WRF (ARW) member (current cycle run plus the
12 h old run).

 - Reduces the number of North American Mesoscale (NAM) 3 km
CONUS nest members in HREF from five to two (previously included
the current cycle plus 6, 12, 18, and 24 hour old runs; now uses
just the current cycle plus the six hour old run).
 - Reduces the number of Nonhydrostatic Multiscale Model on
B-grid (NMMB) members from HIRESW from three to two (previously
included the current cycle plus the 12 and 24 hour old runs; now
uses just the current cycle plus the 12 h old run).

 - Reduces the number of HIRESW WRF-ARW members from three to
two (previously included the current cycle plus the 12 and 24
hour old runs; now uses just the current cycle plus the 12 h old
run).

For the Alaska, Hawaii, and Puerto Rico domains:

 - Generates new HREF products from a six-member ensemble (two
cycles each of HIRESW NMMB, HIRESW ARW, and HIRESW ARW mem2)

2) Changes to HIRESW model runs:

- Unifies the horizontal grid spacing at 3 km for both the ARW
and NMMB models (3.2 km for both over CONUS).

- Changes horizontal grid spacing (new km/old km)
 For the WRF-ARW runs over the five domains:
  - CONUS (3.2/4.2)
  - Alaska (3.0/3.5)
  - Hawaii (3.0/3.8)
  - Guam (3.0/3.8)
  - Puerto Rico (3.0/3.8)
 For the NMMB run over one domain only
  - CONUS (3.6 to 3.2)

- Adds a second ARW member for all domains, except for Guam,
that is initialized from the NAM. This second member also uses
the Mellor Yamada Janjic (MYJ) planetary boundary layer (PBL)
and MYJ surface layer physics, so differs from primary HIRESW
ARW member in terms of the physics used in addition to having a
different source of initial and lateral boundary conditions.  It
also has just 40 vertical levels, while the primary ARW member
has 50 vertical levels.

The NMMB run increases the call frequency for PBL/surface
physics and microphysics from every fourth model time-step to
every other time-step.

- Changes the vertical level structure within the primary 50
level ARW runs for all domains except Alaska. Counting from the
surface upward, layers 7-18 (roughly 970 to 760 hPa for a
surface pressure of 1010 hPa) are made somewhat thicker, and
layers 19-30 (roughly 690 to 330 hPa for a surface pressure of
1010 hPa) are made somewhat thinner.  This change was made for
Alaska only in a previous fix to improve numerical stability,
and is extended to all domains with this upgrade.

- Runs considerably earlier within production suite by using
6 hr old GFS (or NAM for the second ARW member) files to
generate lateral boundary conditions.  Runs that use the GFS for
initial conditions now utilize a 6 hr forecast from the 6 hr old
GFS for initialization.

- Changes from 0.5 degree to 0.25 degree GFS data for use in
producing initial and lateral boundary conditions.

- Initializes the Puerto Rico domain runs from the RAP
(previously initialized from the GFS); the new second ARW member
for Puerto Rico is NAM initialized.

3) Changes to Output

The following changes are on the NCEP Web Services:
 http://nomads.ncep.noaa.gov/pub/data/nccf/com
 http://www.ftp.ncep.noaa.gov/data/nccf/com
 ftp://ftp.ncep.noaa.gov/pub/data/nccf/com
Where the HIRESW is available under:
 hiresw/prod/hiresw.YYYYMMDD
Where the HREF is available under:
 hiresw/prod/href.YYYYMMDD
Where YYYYMMDD is year, month and day

HREF Product Changes:

- The HREF directory will be changing to include subdirectory
hiresw/prod/href.YYYYMMDD/file ->
hiresw/prod/href.YYYYMMDD/ensprod/file
Where file is the href GRIB2 output

- HREF includes two new output file types: probability matched
mean (pmmn), and an "avrg" type which averages the conventional
mean and probability matched mean.

- The HREF file naming structure is changed due to introduction
of non-CONUS output:
href.tCCz.TYPE.fFF.grib2 > href.tCCz.GRID.TYPE.fFF.grib2
 Where CC is cycle, GRID is domain (conus, ak, pr or hi), TYPE
is either mean, sprd, prob, pmmn or avrg; and FF is forecast
hour from 00-36.

- All HREF Output frequency changed from three hourly to hourly,
still extending to 36 hr from the initialization time.

- Cycle output for the "conus" domain is generated at
00/06/12/18 UTC. For the Alaska (ak) and Puerto Rico (pr)
domains output is produced at 06/18 UTC. For Hawaii (hi) output
is generated at 00/12 UTC

- Add neighborhood probability output for more localized fields;
which fields are neighborhood probabilities is specified later
in this subsection in descriptions of "prob" file type changes.

- Adding new NOMADS Grib Filter functionality.
  HREF Conus - filter_hrefconus.pl
  HREF Alaska - filter_hrefak.pl
  HREF Hawaii - filer_hrefhi.pl
  HREF Puerto Rico - filter_hrefpr.pl

- Eliminated fields for HREF "mean" and "sprd" file types:
 500 hPa absolute vorticity (ABSV)

- Added the following fields for HREF "sprd" and "mean" file
types:

Convective Available Potential Energy (CAPE): 90-0 hPa AGL mixed
layer, 180-0 hPa AGL most unstable and surface based
Convective Inhibition (CIN): 90-0 hPa AGL mixed layer, 180-0 hPa
AGL most unstable and surface based
3000-0 m AGL helicity
Geopotential Height: 250, 700 and 925 hPa
Soil temperature in 0-10 cm layer
Soil moisture in 0-10 cm layer
U wind component: 250, 500, 700 and 925 hPa.
V wind component: 250, 500, 700 and 925 hPa.
Temperature: 250, 500, 700, and 925 hPa
Dewpoint temperature: 500, 700, 850, and 925 hPa
Wind speed at 250 and 925 hPa
Cloud base height
Low, middle, high and total cloud fraction
2 m AGL temperature and dewpoint
10 and 80 m AGL wind speed
Precipitation type (as rain, freezing rain, ice pellets, and
snow)
1 h precipitation accumulation
700-500 hPa mean vertical velocity
Haines Index
Wind shear over 0-6000 m layer
1 h accumulated snowfall liquid equivalent
3 h accumulated snowfall liquid equivalent [only for forecast
hours dividing evenly into 3]

- Added fields for HREF "sprd" file type:

1000 m AGL simulated reflectivity
1000 m AGL hourly maximum simulated reflectivity
Composite simulated reflectivity
Echo top height
Updraft helicity over 5000-2000 m AGL layer
Hourly maximum updraft helicity over 5000-2000 m AGL layer
Surface height (topography)

- This upgrade also corrects the derived forecast type labeling
for "sprd" GRIB2 output to label it as the spread of all members
rather than the weighted mean of all members. In wgrib2
inventory form:

xx hour fcst:wt mean all members  --->xx hour fcst:spread all
members

- Eliminated fields for HREF "prob" file type:

Hourly maximum updraft velocity over 400-1000 hPa layer (> 5
m/s)
Hourly maximum downdraft velocity over 400-1000 hPa layer (> 1
m/s, > 5 m/s, > 10 m/s)
U and V components of hourly maximum 10 m AGL wind (> 15.4 m/s)
Echo Top height (> 1000 m, > 3000 m, > 5000 m, > 7600 m, >
10000m)
3 h accumulated precipitation (> 0.24 mm, > 6.34 mm, > 12.4 mm,
> 25.1 mm, > 50 mm, > 75 mm)
Wind speed at 500 and 250 hPa (> 10.3 m/s, > 20.6 m/s , > 30.9
m/s, > 41.2 m/s, > 51.5 m/s)
Low-level (sfc) wind shear > 20 kts

- Added fields for prob file type:

** = a neighborhood probability computed field

**1000 m AGL simulated reflectivity (> 30 dBZ, > 50 dBZ)
**1000 m AGL hourly maximum simulated reflectivity (> 50 dBZ)
**Echo Top height (> 6096 m, > 9144 m, > 10668 m, > 12192 m, >
15240 m)
**Updraft Helicity (> 25 m^2/s^2, >100 m^2/s^2)

**Hourly maximum updraft helicity (> 100 m^2/s^2)
**Hourly maximum updraft velocity over 400-1000 hPa layer (> 20
m/s)
90-0 m AGL mixed layer CAPE (> 500 J/kg, > 1000 J/kg, > 1500
J/kg, > 2000 J/kg, > 3000 J/kg)
90-0 m AGL mixed layer CIN (< 0 J/kg, < -50 J/kg, < -100 J/kg, <
-400 J/kg)
3000-0 m AGL helicity (> 100 m^2/s^2, > 200 m^2/s^2, > 400
m^2/s^2)
2 m temperature (< 273.15 K)
2 m dewpoint temperature (> 283.15 K, > 285.93 K, > 288.71 K, >
291.48 K, > 294.26 K)
Wind shear over 0-6000 m AGL layer (> 10.3 m/s , > 15.4 m/s , >
20.6 m/s, > 25.7 m/s)
Low-level (sfc) wind shear > 10.3 m/s

**1 h accumulated precipitation (> 0.25 mm, > 6.35 mm, > 12.7
mm, > 25.4 mm, > 50.8 mm, > 76.2 mm)
**3 h accumulated precipitation (> 0.25 mm, > 6.35 mm, > 12.7
mm, > 25.4 mm, > 50.8 mm, > 76.2 mm) [only for forecast hours
dividing evenly into 3]
** 6 h accumulated precipitation (> 0.25 mm, > 6.35 mm, > 12.7
mm, > 25.4 mm, > 50.8 mm, > 76.2 mm) [for forecast hours >=6
that divide evenly into 3]
** 12 h accumulated precipitation (> 2.54 mm, > 6.35 mm, > 12.7
mm, > 25.4 mm > 50.8 mm,  > 76.2 mm,  > 127.0 mm) [for forecast
hours >= 12 that divide evenly into 3]
** 24 h accumulated precipitation (> 2.54 mm, > 6.35 mm, > 12.7
mm, > 25.4 mm > 50.8 mm,  > 76.2 mm,  > 127.0 mm) [for forecast
hours >= 24 that divide evenly into 3]

**1 h snowfall liquid equivalent (> 2.54 mm, > 7.62 mm)
**3 h snowfall liquid equivalent (> 2.54 mm, > 7.62 mm, > 15.24
mm) [only for forecast hours dividing evenly into 3]
**6 h snowfall liquid equivalent (> 2.54 mm, > 7.62 mm, > 15.24
mm, > 30.48 mm) [for forecast hours >=6 that divide evenly into
3]

- The labeling for the probability of the mean wind over the
850-300 mb layer has been corrected.  It previously was labeled
as an isobaric layer relative to ground surface, but now is
labeled purely as an isobaric layer.  In wgrib2 inventory form:
WIND:850-300 mb above ground:xx hour fcst:prob <5    --->
WIND:850-300 mb:xx hour fcst:prob <5

- The new probability matched (PM) mean pmmn file type and the
new avrg file type, which contains an average of the PM mean
and conventional arithmetic mean, both contain:

1000 m AGL simulated reflectivity
1000 m AGL hourly maximum simulated reflectivity
Composite simulated reflectivity
Echo top height
Updraft helicity over 5000-2000 m AGL layer
Hourly maximum updraft helicity over 5000-2000 m AGL layer
Surface height (topography)
1 h accumulated precipitation
3 h accumulated precipitation [only for forecast hours dividing
evenly into 3]

Changes HIRESW products:

- For the HIRESW *_5km.*.grib2 and *subset.grib2 output grids,
these new products are added:
 2000-5000 m AGL hourly minimum updraft helicity
 0-3000 m AGL hourly maximum updraft helicity
 0-3000 m AGL hourly minimum updraft helicity
 100-1000 hPa hourly maximum updraft velocity (replaces a 400-
1000 hPa hourly maximum updraft velocity field)
 100-1000 hPa hourly maximum downdraft velocity (replaces a
400-1000 hPa hourly maximum downdraft velocity field)

-For the HIRESW *_5km.*.grib2 (non-subset) output grids, these
new products are added:
VUCSH Vertical U-Component Shear [1/s]:0-6000 m above ground
VVCSH Vertical V-Component Shear [1/s]:0-6000 m above ground

-For the HIRESW *_5km.*.grib2 Conus only (non-subset) output
grids, these new products are added:
  CPOFP Percent frozen precipitation
  APCP Total Precipitation [kg/m^2]:surface:3-6 hour acc fcst
  WEASD Water Equivalent of Accumulated Snow Depth
[kg/m^2]:surface:3-6 hour acc fcst

- For the HIRESW *_2p5km*.grib2 and *_3km*.grib2 (non-subset)
grids, two new products are added:
 HGT Cloud ceiling
 HGT Cloud base
100-1000 hPa hourly maximum updraft velocity (replaces a 400-
1000 hPa hourly maximum updraft velocity field)
 100-1000 hPa hourly maximum downdraft velocity (replaces a
400-1000 hPa hourly maximum downdraft velocity field)

- For the HIRESW *_2p5km*conus.grib2 (non-subset) grids,
following product is removed:
  MAXDVV Hourly Maximum of Downward Vertical Velocity

- The CONUS subset grid with a reduced number of products now
is output on a 1799 x 1059 point 3 km grid (the same grid
utilized for HRRR and NAM CONUS nest output).

- The file name structure for the CONUS subset grid is changed
to reflect the change in output grid spacing:
hiresw.tCCz.*_5km.fFF.conus.subset.grib2 -->
hiresw.tCCz.*_3km.fFF.conus.subset.grib2

- A new member will be available for the CONUS domain
hiresw.tCCz.*_3km.fFF.conusmem2.subset.grib2

- HIRESW Time labeling for time-averaged surface fluxes
(sensible and latent heat) in NMMB model output have been
corrected for forecast hours not divisible by 3. As an example,
a wgrib2 inventory of a 20 hour forecast of time-averaged latent
heat flux would change in this way:
LHTFL:surface:--->  LHTFL:surface:18-20 hour ave fcst:

- Some BUFR output points have been eliminated or redefined:

All eliminated points are fictitious stations over the ocean
previously added to fill in around the limited stations on land
for Hawaii (HI), Puerto Rico (PR), and Guam.  Details are
available at:
http://www.emc.ncep.noaa.gov/mmb/mpyle/hiresw/bufr_changes/hires
wv7.txt

And while not documented, all domains that had a change in
resolution (all ARW domains and the CONUS NMMB) will have some
slight changes in the exact location of individual BUFR output
stations.  Changes to the grid resolution modifies the grid
dimensions and grid point locations, and because the BUFR output
is taken from values at the nearest model grid point it may be
shifted by up to a few kilometers.

- The HIRESW 5km data will be discontinued from the NWS web
services, and can instead be found on the NCEP web services.
Please see below for what is being removed, and the exact
replacement file name on NCEP web services. Users are encouraged
to migrate over to the NCEP web files at any time.

http://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.hires_MR.arw_CY
.CC/
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.hires_MR.arw_CY.
CC/
http://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.hires_MR.nmm_CY
.CC/
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.hires_MR.nmm_CY.
CC/
Subdirectories
RD.YYYYMMDD/PT.grid_DF.gr2_AR.conus05/
RD.YYYYMMDD/PT.grid_DF.gr2_AR.alaska05/
RD.YYYYMMDD/PT.grid_DF.gr2_AR.hi05/
RD.YYYYMMDD/PT.grid_DF.gr2_AR.pr05/
Where CC is cycle and YYYYMMDD is year, month and day

PT.grid_DF.gr2_AR.conus05 fh.00FF_tl.press_gr.awpreg ->
hiresw.tCCz.arw_5km.fFF.conus.grib2
hiresw.tCCz.nmmb_5km.fFF.conus.grib2

PT.grid_DF.gr2_AR.alaska05 fh.00FF_tl.press_gr.awpreg  ->
hiresw.tCCz.arw_5km.fFF.ak.grib2
hiresw.tCCz.nmmb_5km.fFF.ak.grib2

PT.grid_DF.gr2_AR.hi05 fh.00FF_tl.press_gr.awpreg ->
hiresw.tCCz.arw_5km.fFF.hi.grib2
hiresw.tCCz.nmmb_5km.fFF.hi.grib2

PT.grid_DF.gr2_AR.pr05 fh.00FF_tl.press_gr.awpreg ->
hiresw.tCCz.arw_5km.fFF.pr.grib2
hiresw.tCCz.nmmb_5km.fFF.pr.grib2
Where FF is forecast hour

NOAAPORT/SBN Additions:

- With this upgrade the HREF will become available over
NOAAPORT/SBN across the CONUS, Alaska, Hawaii and Puerto Rico
domains. The total volume increase with be 8.6GB/day. Please see
this document below for the description of product WMO headers:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/HREF_WMO_descripti
on.pdf

Please see this document for every WMO header available:

http://www.emc.ncep.noaa.gov/mmb/mpyle/hiresw/wmo/wmo_headers.tx
t

Data Availability and Schedule Changes:

With the change in initialization procedures described earlier,
HIRESW output will be made available much earlier:

~115 minutes earlier for CONUS domain
~115 minutes earlier for Alaska domain
~95 minutes earlier for Hawaii domain
~110 minutes earlier for Puerto Rico domain
~110 minutes earlier for Guam domain

CONUS HREF output will be available about 110 minutes earlier
than in current operations.

New HREF domain output will be available approximately this long
after the nominal cycle (CC) time:

Alaska: CC + 02:55
Hawaii: CC + 02:45
Puerto Rico:  CC + 02:45

A consistent parallel feed of data is currently available on the
NCEP HTTP server at the following URL:

http://para.nomads.ncep.noaa.gov/pub/data/nccf/com/hiresw/para/
http://para.nomads.ncep.noaa.gov/pub/data/nccf/noaaport/

NCEP urges all users to ensure their decoders can handle changes
in content order, changes in the scaling factor component within
the product definition section (PDS) of the GRIB files, and
volume changes. These elements may change with future NCEP model
implementations. NCEP will make every attempt to alert users to
these changes before implementation.

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 questions regarding these changes, please contact:

Matthew Pyle
NCEP/EMC Engineering and Implementation Branch
College Park, MD
3016833687
Matthew.Pyle@noaa.gov

For questions regarding the data flow aspects, please contact:

Carissa Klemmer
NCEP/NCO Dataflow Team Lead
College Park, MD
3016830567
ncep.list.pmb-dataflow@noaa.gov

NWS Service Change Notices are online at:

   http://www.weather.gov/om/notif.htm



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