NOUS41 KWBC 312054 AAA

PNSWSH

 

Technical Implementation Notice 15-34, Amended

National Weather Service Headquarters Washington DC

0455 PM EDT Mon Aug 31 2015

 

To:       Subscribers:

          -Family of Services

          -NOAA Weather Wire Service

          -Emergency Managers Weather Information Network

          -NOAAPORT

          Other NWS Partners, Users and Employees

 

From:     Tim McClung

          Chief Operating Officer

          Office of Science and Technology Integration

 

Subject:  Amended: Changes to GFS-based Model Output Statistics

          (MOS)Guidance effective October 1, 2015

 

Amended to change the implementation date from Tuesday, September

15, 2015, to Thursday, October 1, 2015. 

 

Users may find parallel data for download on NOAA's Operational

Model Archive and Distribution System (NOMADS) at the following

link (files will reside in gfsmos.YYYYMMDD):

 

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

 

On or about Thursday, October 1, 2015, beginning with the

1200 Coordinated Universal Time (UTC) model run, the NWS

Meteorological Development Laboratory (MDL) will implement

changes to the Global Forecast System (GFS)-based Model Output

Statistics (MOS) guidance. The changes will include:

 

1.  Add gridded MOS guidance for CONUS and Alaska for the

Day 8-11 period. Guidance will be available for the following

elements:

 

1) 2-meter temperature (every 6 h)

2) 2-meter dew point temperature (every 6 h)

3) Daytime maximum temperature

4) Nighttime minimum temperature

5) Relative humidity (every 6 h)

6) Wind speed (every 6 h)

7) Wind direction (every 6 h)

8) 12-h probability of precipitation (every 12 h)

 

These day 8-11 products will be produced on a 2.5-km Lambert

Conformal grid over the CONUS and 3-km Polar Stereographic grid

over Alaska.  Guidance will be available for the 0000 and

1200 UTC model cycles for projections out to 11 days in advance. 

These Day 8-11 Gridded MOS products will be disseminated on the

Satellite Broadcast Network (SBN), NOAAPORT, and the NWS FTP

server in GRIB2 format. Users can view Gridded MOS guidance for

the expanded CONUS domain at the following link (this page is not

operationally supported and guidance may not be current):

 

http://www.mdl.nws.noaa.gov/~mos/gmos/conus25_all/view_gmos.php

 

The day 8-11 products for the CONUS and Alaska will be available

in GRIB2 format in the experimental area of the National Digital

Guidance Database (NDGD) on the NWS ftp server at:

 

ftp://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.mosgfs/AR.conus/

 

ftp://tgftp.nws.noaa.gov/SL.us008001/ST.expr/DF.gr2/DC.ndgd/GT.mosgfs/AR.alaska/

 

Each element-specific GRIB2 file will reside in the VP.008-450

directory and contain a WMO super header and individual headers. 

A listing of the GRIB2 file names for each element is given in

Table 1 below.  Tables 2 and 3 list WMO super headers for CONUS

and Alaska Day 8-11 gridded MOS elements.

 

A Web page outlining the gridded MOS guidance and the ftp server

structure can be found at:

 

http://www.nws.noaa.gov/mdl/synop/gmos.php

 

2.  This change will expand the output mask for the 2.5-km CONUS

grid northward from its current National Digital Forecast

Database (NDFD) extent to include all of the Northwest River

Forecast Center basin and a buffer of 170 km elsewhere along the

border with Canada. This change will affect the following 2.5-km

CONUS Gridded MOS elements:

 

1) 2-meter temperature

2) 2-meter dew point temperature

3) Daytime maximum temperature

4) Nighttime minimum temperature

5) Wind speed, wind direction, wind gust

6) 6-h/12-h probability of precipitation

7) 6-h/12-h quantitative precipitation amount

8) Relative humidity

9) Total sky cover

10) 24-h snowfall amount 

 

The northward expansion of the 2.5-km CONUS grid will result in a

small increase in GRIB2 file sizes (generally less than 10

percent) for the above listed elements. Grids of 24-h snowfall

amount will be clipped to their current extent and contain

missing values elsewhere. Other elements not listed above will

not be affected by the grid expansion. WMO super headers for the

2.5-km CONUS Gridded MOS elements affected by this change are

listed in Table 4 below. The operational 5-km CONUS Gridded MOS

products will remain on their current NDFD extent and will not be

affected by the expansion of the 2.5-km CONUS grids.

 

3.  NWS will add new stations to the GFS-based short-range and

extended-range Cooperative Observer Program (COOP) maximum and

minimum temperature messages, known by their AWIPS IDs MCG and

MCX, respectively.  Communication identifiers for affected

products are listed in Table 5 below. A list of the stations

being added can be found at:

 

http://www.nws.noaa.gov/mdl/synop/gfsmos_changes/newsitesSept2015.php

 

4.  NWS will remove stations from the GFS-based short-range and

extended-range COOP maximum and minimum temperature messages,

known by their AWIPS IDs MCG and MCX, respectively. These are

stations that have closed, stopped reporting, or do not contain

sufficient cases to develop MOS equations. Communication

identifiers for the affected products are listed in Table 5

below. A list of the stations being removed can be found at:

 

http://www.nws.noaa.gov/mdl/synop/gfsmos_changes/droppedsitesSept2015.php

 

5.  NWS will remove stations from the GFS-based River Forecast

Center maximum and minimum temperature SHEF message with AWIPS ID

FTP. These are stations that have closed, stopped reporting, or

do not contain sufficient cases to develop MOS equations. 

Communication identifiers for the affected products are listed in

Table 6 below. Stations being removed can be found at:

 

http://www.nws.noaa.gov/mdl/synop/gfsmos_changes/droppedsitesSept2015.php

 

6.  This change provides updated thunderstorm guidance for Alaska

valid for the warm season, May through September. NWS has updated

guidance for the probability of a thunderstorm in 3-, 6-, 12- and 

24-h periods over Alaska with more recent model data and

lightning observations. This updated guidance will take effect at

the beginning of the next warm season (May 1, 2016). 

Communication identifiers for the products affected by this

update are listed in Tables 7 and 8 below.

 

Table 1: GRIB2 file names for the day 8-11 GFS-based Gridded MOS

elements (These files will reside in the VP.008-450 directory on

the ftp server.)

 

GRIB2 FILE NAME   ELEMENT

---------------   -----------------------------

ds.wdir.bin       Wind direction

ds.wspd.bin       Wind speed

ds.pop12.bin      12-h prob. of precipitation

ds.temp.bin       2-meter temperature

ds.td.bin         2-meter dew point temperature

ds.maxt.bin       Daytime maximum temperature

ds.mint.bin       Nighttime minimum temperature

ds.rhm.bin        Relative humidity

 

Table 2: WMO super headers for the day 8-11 Gridded MOS products

over the CONUS

 

WMO SUPERHEADER   ELEMENT

---------------   -----------------------------

YBUZ96 KWBQ       Wind direction

YCUZ96 KWBQ       Wind speed

YDUZ96 KWBQ       12-h prob. of precipitation

YEUZ96 KWBQ       2-meter temperature

YFUZ96 KWBQ       2-meter dew point temperature

YGUZ96 KWBQ       Daytime maximum temperature

YHUZ96 KWBQ       Nighttime minimum temperature

YRUZ96 KWBQ       Relative humidity

 

Table 3: WMO super headers for the day 8-11 Gridded MOS products

over Alaska

 

WMO SUPERHEADER   ELEMENT

---------------   -----------------------------

LBRZ96 KWBQ       Wind direction

LCRZ96 KWBQ       Wind speed

LDRZ96 KWBQ       12-h prob. of precipitation

LERZ96 KWBQ       2-meter temperature

LFRZ96 KWBQ       2-meter dew point temperature

LGRZ96 KWBQ       Daytime maximum temperature

LHRZ96 KWBQ       Nighttime minimum temperature

LRRZ96 KWBQ       Relative humidity

 

Table 4. WMO superheaders for each 2.5-km CONUS Gridded MOS

element affected by the grid expansion.  Listed below are

representations of the superheaders where ii=98 for short-range

guidance (days 1-3) and ii=97 for medium-range guidance (days 4-

7). Elements indicated by (**) will include ii=96 for extra

extended-range (days 8-11).

 

WMO SUPERHEADER   ELEMENT

---------------   -----------------------------

YAUZii KWBQ       Total sky cover

YBUZii KWBQ**     Wind direction

YCUZii KWBQ**     Wind speed

YDUZii KWBQ**     12-h prob. of precipitation

YEUZii KWBQ**     2-meter temperature

YFUZii KWBQ**     2-meter dew point temperature

YGUZii KWBQ**     Daytime maximum temperature

YHUZii KWBQ**     Nighttime minimum temperature

YIUZii KWBQ       6-h quant. precipitation amount

YRUZii KWBQ**     Relative humidity

YSUZii KWBQ       24-h snowfall amount

YUUZii KWBQ       6-h prob. of precipitation

YVUZii KWBQ       12-h quant. precipitation amount

YWUZii KWBQ       Wind Gusts

 

Table 5:  Communication identifiers for the GFS-based COOP

maximum and minimum temperature text products affected by the

changes

 

WMO HEADING       AWIPS ID

-----------       --------

FOUS10 KWNO       MCGUSA   (Short-range)         

FEUS10 KWNO       MCXUSA   (Extended-range)

 

Table 6: Communication identifiers for the GFS-based River

Forecast Center SHEF products affected by the changes

 

   WMO HEADING      AWIPS ID

   -----------      --------

   FOUS12 KWNO      FTPCIN

   FOUS12 KWNO      FTPHFD

   FOUS12 KWNO      FTPKRF

   FOUS12 KWNO      FTPMSR

   FOUS12 KWNO      FTPPTR 

   FOUS12 KWNO      FTPRHA 

   FOUS12 KWNO      FTPRSA

   FOUS12 KWNO      FTPSLR 

   FOUS12 KWNO      FTPTUR

   FOAK12 KWNO      FTPACR

 

Table 7: Communication identifiers for the GFS-based MOS text

products affected by the updated Alaska thunderstorm guidance

 

   WMO HEADING      AWIPS ID

   -----------      --------

   FOAK37 KWNO      MAVAJK

   FOAK38 KWNO      MAVAFC

   FOAK39 KWNO      MAVAFG

   FEAK37 KWNO      MEXAJK

   FEAK38 KWNO      MEXAFC

   FEAK39 KWNO      MEXAFG

 

Table 8: Representations of WMO headers for the Alaska Gridded

MOS products affected by the updated thunderstorm guidance, where

XXX represents the valid day and time

 

WMO SUPERHEADER   ELEMENT

---------------   -----------------------------

   LJRXXX KWBQ     3-h Prob. of a thunderstorm

   LYRXXX KWBQ     6-h Prob. of a thunderstorm

   LXRXXX KWBQ     12-h Prob. of a thunderstorm

 

For questions regarding the above changes to the GFS-based MOS

guidance, please contact:

 

  Phil Shafer

  MDL/Silver Spring, Maryland

  301-427-9488

  Phil.Shafer@noaa.gov

or

  Matthew Peroutka

  MDL/Silver Spring, Maryland

  301-427-9483

  Matthew.Peroutka@noaa.gov

 

Links to MOS products and descriptions are online at:

 

  http://www.nws.noaa.gov/mdl/synop

 

 National Technical Implementation Notices are online at: 

 

  http://www.weather.gov/om/notif.htm

 

$$