NOUS41 KWBC 181500 AAC

PNSWSH

 

Technical Implementation Notice 16-33

National Weather Service Headquarters Washington DC

800 AM EDT Tue Oct 18 2016

 

To:       Subscribers

          -NOAA Weather Wire Service

          -Emergency Managers Weather Information Network

          -NOAAPORT

          Other NWS Partners, Users and Employees

 

From:     Tim McClung

          Portfolio Manager

          Office of Science and Technology Integration

 

Subject:  Amended: Implementation of experimental National Blend

          of Models guidance effective November 15, 2016, and

          request for comments

 

Amended to postpone the implementation date from Thursday,

November 3, 2016, to Tuesday, November 15, 2016

 

On or about Tuesday, November 15, 2016, beginning with the

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

Meteorological Development Laboratory (MDL) will implement an

update to the experimental National Blend of Models (NBM)

guidance for the CONUS. Comments will be collected through

February 28, 2017. As a part of this upgrade, experimental NBM

guidance will be added for the Alaska, Hawaii, Puerto Rico and

Oceanic National Digital Forecast Database (NDFD) domains.

 

Experimental NBM guidance over the CONUS will be updated with

additional model inputs and extended to 264 hours for the

following weather elements:

 

     1. Sky cover

     2. 10-m wind direction

     3. 10-m wind speed

     4. 2-m temperature

     5. 2-m dewpoint temperature

     6. Daytime maximum temperature

     7. Nighttime minimum temperature

     8. 2-m relative humidity

     9. 2-m apparent temperature

     10. 10-m wind gust

 

Experimental NBM guidance will be added for the following

weather elements over the CONUS:

 

     1. Quantitative precipitation amount (6-hour)

     2. Probability of Precipitation (12-hour)

 

The CONUS NBM products will continue to be produced on a 2.5-km

Lambert Conformal grid with dimensions NX=2145 and NY=1597.

This represents an expansion to the north by 220 grid lengths

compared to the current National Digital Forecast Database

(NDFD) CONUS grid, in order to provide coverage for the entire

Northwest River Forecast Center basin.  Guidance will be

available for the 0000 and 1200 UTC model cycles for projections

from 6 hours to 264 hours in advance.

 

Experimental NBM guidance will be added for the following

weather elements over the Alaska, Hawaii and Puerto Rico NDFD

domains:

 

     1. Sky cover

     2. 10-m wind direction

     3. 10-m wind speed

     4. 2-m temperature

     5. 2-m dewpoint temperature

     6. Daytime maximum temperature

     7. Nighttime minimum temperature

     8. 2-m relative humidity

     9. 2-m apparent temperature

     10. 10-m wind gust

 

The Alaska NBM products will be produced on a 3-km Polar

Stereographic grid with dimensions NX=1649 and NY=1105.  The

Hawaii NBM products will be produced on a 2.5-km Mercator grid

with dimensions NX=625 and NY=561.  The Puerto Rico NBM products

will be produced on a 1.25-km Mercator grid with dimensions

NX=353 and NY=257.  Alaska, Hawaii and Puerto Rico NBM guidance

will be available for the 0000 and 1200 UTC model cycles for

projections from 6 hours to 264 hours in advance.

 

Experimental NBM guidance will be added for the following

weather elements over the Oceanic NDFD domain:

 

     1. 10-m wind speed exceedance value for the 50th

        percentile

 

The Oceanic NBM products will be produced on a 10-km Mercator

grid with dimensions NX=2517 and NY=1817.  The Oceanic NBM

guidance will be available for the 0000 and 1200 UTC model

cycles for projections from 6 hours to 264 hours in advance.

 

All experimental NBM products will be disseminated on the

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

server in GRIB2 format.

 

All NBM products will be available in GRIB2 format on or about

Wednesday, September 21, 2016, 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.blend/AR.conus/  (CONUS)

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

lend/AR.alaska/ (Alaska)

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

lend/AR.hawaii/ (Hawaii)

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

lend/AR.puertori/(Puerto Rico)

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

lend/AR.oceanic/  (Oceanic)

 

This directory will contain subdirectories for each valid period

as follows:

 

     VP.001/      Day 1

     VP.002/      Day 2

     VP.003/      Day 3

     VP.004/      Day 4

     VP.005-007/  Days 5-7

     VP.008-450/  Days 8 and beyond

 

Each element-specific GRIB2 file will reside in the appropriate

valid period subdirectory and contain a WMO superheader and

individual headers.  A listing of the GRIB2 file names for each

element is given in Table 1 below.  WMO superheaders for the NBM

products are given in Table 2.

 

Table 1: GRIB2 file names for the NBM elements

 

These files will reside in the appropriate valid period

subdirectory on tgftp.

 

   GRIB2 FILE NAME   ELEMENT

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

   ds.skymean.bin    Sky cover

   ds.wdirmean.bin   Wind direction

   ds.wspdmean.bin   Wind speed

   ds.pop12.bin      12-h probability of precipitation

   ds.tempmean.bin   2-m temperature

   ds.tdmean.bin     2-m dewpoint temperature

   ds.maxtmean.bin   Daytime maximum temperature

   ds.mintmean.bin   Nighttime minimum temperature

   ds.qpf06.bin      6-h quantitative precipitation amount

   ds.rhmean.bin     2-m relative humidity

   ds.apptmean.bin   2-m apparent temperature

   ds.wgustmean.bin  Wind gust

 

Table 2: WMO superheaders for each CONUS NBM element

 

Listed below are representations of the superheaders where ii=98

for day 1, ii=97 for day 2, ii=96 for day 3, ii=95 for day 4,

ii=94 for days 5-7, and ii=93 for days 8 and beyond.

 

   WMO SUPERHEADER   ELEMENT

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

   LAAZii KWEA       Sky cover

   LBAZii KWEA       Wind direction

   LCAZii KWEA       Wind speed

   LDAZii KWEA       Probability of Precipitation (12h)

   LEAZii KWEA       2-m temperature

   LFAZii KWEA       2-m dewpoint temperature

   LGAZii KWEA       Daytime maximum temperature

   LHAZii KWEA       Nighttime minimum temperature

   LIAZii KWEA       Quantitative Precipitation Amount (6h)

   LRAZii KWEA       2-m relative humidity

   LTAZii KWEA       2-m apparent temperature

   LWAZii KWEA       Wind gust

 

Table 3: WMO superheaders for each Alaska NBM element

 

Listed below are representations of the superheaders where ii=98

for day 1, ii=97 for day 2, ii=96 for day 3, ii=95 for day 4,

ii=94 for days 5-7, and ii=93 for days 8 and beyond.

 

   WMO SUPERHEADER   ELEMENT

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

   MAAZii KWEA       Sky cover

   MBAZii KWEA       Wind direction

   MCAZii KWEA       Wind speed

   MEAZii KWEA       2-m temperature

   MFAZii KWEA       2-m dewpoint temperature

   MGAZii KWEA       Daytime maximum temperature

   MHAZii KWEA       Nighttime minimum temperature

   MRAZii KWEA       2-m relative humidity

   MTAZii KWEA       2-m apparent temperature

   MWAZii KWEA       Wind gust

 

Table 4: WMO superheaders for each Hawaii NBM element

 

Listed below are representations of the superheaders where ii=98

for day 1, ii=97 for day 2, ii=96 for day 3, ii=95 for day 4,

ii=94 for days 5-7, and ii=93 for days 8 and beyond.

 

   WMO SUPERHEADER   ELEMENT

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

   ZAAZii KWEA       Sky cover

   ZBAZii KWEA       Wind direction

   ZCAZii KWEA       Wind speed

   ZEAZii KWEA       2-m temperature

   ZFAZii KWEA       2-m dewpoint temperature

   ZGAZii KWEA       Daytime maximum temperature

   ZHAZii KWEA       Nighttime minimum temperature

   ZRAZii KWEA       2-m relative humidity

   ZTAZii KWEA       2-m apparent temperature

   ZWAZii KWEA       Wind gust

 

Table 5: WMO superheaders for each Puerto Rico NBM element

 

Listed below are representations of the superheaders where ii=98

for day 1, ii=97 for day 2, ii=96 for day 3, ii=95 for day 4,

ii=94 for days 5-7, and ii=93 for days 8 and beyond.

 

   WMO SUPERHEADER   ELEMENT

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

   YAAZii KWEA       Sky cover

   YBAZii KWEA       Wind direction

   YCAZii KWEA       Wind speed

   YEAZii KWEA       2-m temperature

   YFAZii KWEA       2-m dewpoint temperature

   YGAZii KWEA       Daytime maximum temperature

   YHAZii KWEA       Nighttime minimum temperature

   YRAZii KWEA       2-m relative humidity

   YTAZii KWEA       2-m apparent temperature

   YWAZii KWEA       Wind gust

 

Table 6: WMO superheaders for each Oceanic NBM element

 

Listed below are representations of the superheaders where ii=98

for day 1, ii=97 for day 2, ii=96 for day 3, ii=95 for day 4,

ii=94 for days 5-7, and ii=93 for days 8 and beyond.

 

   WMO SUPERHEADER   ELEMENT

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

   HCAZii KWEA       Wind speed (50th percentile exceedance)

   

Beginning approximately one month prior to the implementation

date, users may find parallel data for download on NOAA's

Operational Model Archive and Distribution System (NOMADS) at

the following link:

 

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

 

Feedback will be collected through February 28, 2017 via

comments provided on the electronic survey at:

 

http://www.nws.noaa.gov/survey/nws-survey.php?code=EXPNBM

 

For questions regarding the implementation of NBM guidance

please contact:

 

  David Myrick

  MDL/Silver Spring, Maryland

  301-427-9455

  David.Myrick@noaa.gov

 

NWS national TINs are online at:

 

  http://www.weather.gov/os/notif.htm

 

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