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/hireswv7.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_description.pdf

 

Please see this document for every WMO header available:

 

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

 

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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