[gradsusr] Updated GFS forecast hours 183-192 information and tips on making sure the data plots correctly.

Fri Jun 4 23:54:53 EDT 2010

FRI 04JUN10: 2045PDT

Dear Grads Users

On 2 APR 2010, NCEP announced the addition of forecast hours to the GFS GRIB2 data set - in essence, extending the high resolution data from 180hrs to 192, every 3 hours. See the official note below.

While testing the data, I noticed that my data was not being mapped corrected by GRADS, so I made sure I updated both g2ctl.pl (version 0.0.4o) AND wgrib2 to the absolute latest version (1.8.4). Once I had done that, the data was mapped correctly by wgrib2 and the plots in GRADS were as expected. I thought I'd pass on this information so that you don't spend hours wondering what's wrong as everything processes just fine with older versions with no warning messages, but the data is totally incorrectly mapped by wgrib2/g2ctl.

Here is the offical wgrib2 page: http://www.cpc.noaa.gov/products/wesley/wgrib2/index.html

Go to the following page to get g2ctl.pl: http://www.cpc.noaa.gov/products/wesley/g2ctl.html

and here for the latest source code for wgrib2 : ftp://ftp.cpc.ncep.noaa.gov/wd51we/wgrib2/

Also, for those of you plotting beyond hour 192 (high resolution) you may want to consider using the GFS Ensemble control run data which has forecasts every 6 hours out to 384 hours and the resolution is 1x1 degrees - this as opposed to the regular GFS which is only every 12hours at 2.5x2.5 degrees.

Here is the official note from NCEP: 

>> 86
>> NOUS41 KWBC 021253
>> PNSWSH
>> 
>> TECHNICAL IMPLEMENTATION NOTICE 10-15
>> NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
>> 853 AM EDT FRI APR 2 2010
>> 
>> TO:       SUBSCRIBERS:
>>         -FAMILY OF SERVICES
>>         -NOAA WEATHER WIRE SERVICE
>>         -EMERGENCY MANAGERS WEATHER INFORMATION NETWORK
>>         -NOAAPORT
>>         OTHER NWS PARTNERS...USERS AND EMPLOYEES
>> 
>> FROM:     TIMOTHY MCCLUNG
>>         SCIENCE PLANS BRANCH CHIEF
>>         OFFICE OF SCIENCE AND TECHNOLOGY
>> 
>> SUBJECT:  GLOBAL FORECAST SYSTEM CHANGES:
>>         EFFECTIVE JUNE 22 2010.
>> 
>> EFFECTIVE JUNE 22 2010...BEGINNING WITH THE 1200 COORDINATED
>> UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS FOR
>> ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE THE GLOBAL
>> FORECAST SYSTEM /GFS/. THE RESOLUTION OF THE GLOBAL FORECAST
>> MODEL WILL BE INCREASED FROM T382 /35 KM/ TO T574 /27 KM/.
>> THE HIGH RESOLUTION PORTION OF THE FORECAST WILL BE EXTENDED
>> FROM 180 HRS TO 192 HRS. WITH THIS EXTENSION 3 HOURLY OUTPUT
>> WILL BE MADE AVAILABLE OUT TO 192 HOURS.
>> 
>> THIS WILL RESULT IN SIGNIFICANT CHANGES IN THE DEFINITION OF
>> PARAMETERS IN THE 192 HOUR PRESSURE GRIB /PGRB/ AND FLUX
>> FILES. THERE WILL ALSO BE SIGNIFICANT CHANGES IN MODEL
>> PHYSICS ASSOCIATED WITH THIS CHANGE. IN ADDITION
>> MODIFICATIONS WILL BE MADE TO THE CONTENTS OF THE GLOBAL DATA
>> ASSIMILATION SYSTEM /GDAS/ AND GFS PGRB FILES.
>> 
>> CHANGES IN MODEL PHYSICS INCLUDE:
>> 
>> RADIATION AND CLOUD OVERLAP
>> GRAVITY WAVE DRAG
>> HURRICANE RELOCATION
>> NEW PLANETARY BOUNDARY LAYER SCHEME
>> NEW MASS FLUX SHALLOW CONVECTION
>> UPDATED DEEP CONVECTION SCHEME
>> POSITIVE DEFINITE TRACER TRANSPORT SCHEME
>> 
>> THE NEW PARAMETER FOR THE GFS FORECAST PRESSURE GRIB
>> FILES IS:
>> 
>> MAX WIND GUST
>> 
>> SEVERAL PARAMETERS ARE BEING DELETED FROM THE GDAS ANALYSIS
>> PRESSURE GRIB FILES BECAUSE THEY ARE NOT VALID FOR THE
>> ANALYSIS DATASET AND HAVE NEVER PROVIDED PERTINENT
>> INFORMATION.  THESE INCLUDE:
>> 
>> 4 PRECIPITATION TYPES
>> CONVECTIVE PRECIPITATION RATE
>> LAND SEA MASK
>> LATENT HEAT FLUX
>> SENSIBLE HEAT FLUX
>> PRECIPITATION RATE
>> 2M RH
>> 2M SPECIFIC HUMIDITY
>> 2M TEMPERATURE
>> BOUNDARY LAYER CLOUD COVER
>> LOW CLOUD COVER
>> CONVECTIVE CLOUD COVER
>> SKIN TEMPERATURE
>> SURFACE UPWARD LONG WAVE FLUX
>> SURFACE UPWARD SHORT WAVE FLUX HELICITY
>> 
>> THESE PARAMETERS ARE BEING DELETED FROM THE GLOBAL FORECAST
>> MODEL SIMULATED GOES GRIB FILE BECAUSE THEY WERE INCLUDED IN
>> ERROR. THESE FIELDS ARE AVAILABLE IN THE PGRB FILES:
>> 
>> MEAN SEA LEVEL PRESSURE
>> WAVE-5 GEOPOTENTIAL HEIGHT
>> 
>> ALL ACCUMULATED OR AVERAGED VALUES IN THE 192 HOUR PGRB
>> AND FLUX FILES WILL NOW BE OVER A 6 HOUR PERIOD INSTEAD OF
>> 12 HOURS. THE FORMAT AND CONTENT OF THE 3 HOURLY FILES FROM
>> 180 TO 192 HOURS WILL BE THE SAME AS THE FILES FROM 0 TO 180.
>> FOR THE FLUX FILE...THIS INCLUDES THE MAJORITY OF THE
>> PARAMETERS IN THE FILE.  PARAMETERS CHANGING IN THE PGRB
>> FILE ARE:
>> 
>> 2 M ABOVE GROUND MAX. TEMPERATURE
>> 2 M ABOVE GROUND MIN. TEMPERATURE
>> SURFACE ALBEDO
>> SURFACE CLEAR SKY UV-B DOWNWARD SOLAR FLUX
>> SURFACE CATEGORICAL FREEZING RAIN
>> SURFACE CATEGORICAL ICE PELLETS
>> SURFACE CONVECTIVE PRECIPITATION RATE
>> SURFACE CATEGORICAL RAIN
>> SURFACE CATEGORICAL SNOW
>> ATMOSPHERIC COLUMN CLOUD WORK FUNCTION
>> SURFACE DOWNWARD LONG WAVE FLUX
>> SURFACE DOWNWARD SHORT WAVE FLUX
>> SURFACE UV-B DOWNWARD SOLAR FLUX
>> SURFACE GROUND HEAT FLUX
>> SURFACE LATENT HEAT FLUX
>> SURFACE PRECIPITATION RATE
>> LOW CLOUD BASE PRESSURE
>> LOW CLOUD TOP PRESSURE
>> MID-CLOUD BASE PRESSURE
>> MID-CLOUD TOP PRESSURE
>> HIGH CLOUD BASE PRESSURE
>> HIGH CLOUD TOP PRESSURE
>> SURFACE SENSIBLE HEAT FLUX
>> ATMOSPHERIC COLUMN TOTAL CLOUD COVER
>> BOUNDARY CLOUD LAYER TOTAL CLOUD COVER
>> LOW CLOUD COVER
>> MID-CLOUD COVER
>> HIGH CLOUD COVER
>> LOW CLOUD TOP TEMPERATURE
>> MID-CLOUD TOP TEMPERATURE
>> HIGH CLOUD TOP TEMPERATURE
>> SURFACE ZONAL GRAVITY WAVE STRESS
>> SURFACE ZONAL MOMENTUM FLUX
>> SURFACE UPWARD LONG WAVE FLUX
>> TOP OF ATMOSPHERE UPWARD LONG WAVE FLUX
>> SURFACE UPWARD SHORT WAVE FLUX
>> TOP OF ATMOSPHERE UPWARD SHORT WAVE FLUX
>> SURFACE MERIDIONAL GRAVITY WAVE STRESS
>> SURFACE MERIDIONAL MOMENTUM FLUX
>> SURFACE CONVECTIVE PRECIPITATION
>> SURFACE TOTAL PRECIPITATION
>> SURFACE LARGE SCALE PRECIPITATION
>> 
>> NOTE THAT FOR THE 192 HR PGRB PRODUCTS AVAILABLE ON NOAAPORT
>> AND IN AWIPS THE ACCUMULATIONS AND AVERAGES WILL REMAIN OVER
>> THE PREVIOUS 12 HOUR PERIOD UNTIL AWIPS IS MODIFIED TO
>> ACCOMMODATE THIS CHANGE.
>> 
>> THE FORMAT OF THE HALF AND ONE DEGREE PRESSURE GRIB FILES
>> WILL REMAIN THE SAME EXCEPT FOR THE CHANGES IN VARIABLES
>> LISTED ABOVE. THE SIZE OF THESE FILES WILL NOT CHANGE
>> SIGNIFICANTLY. WITH THE INCREASE IN MODEL RESOLUTION... THE
>> SIZE OF THE SIGMA COEFFICIENT FILES AND THE SURFACE FLUX
>> FILES WILL INCREASE SIGNIFICANTLY.
>> 
>> THESE CONTENT CHANGES WILL IMPACT ALL DISSEMINATION ROUTES:
>> NWS PUBLIC FTP SERVER...THE NCEP PUBLIC FTP SERVER...AND
>> NOAAPORT.
>> 
>> A SET OF TEST DATA IS AVAILABLE AT /USE LOWERCASE/ EXCEPT FOR
>> GFS AND T574L64:
>> 
>> FTP.EMC.NCEP.NOAA.GOV/GC_WMB/WX24FY/GFS_T574L64/GFS.20091217
>> 
>> A CONSISTENT PARALLEL FEED OF DATA WILL BECOME AVAILABLE ON
>> THE NCEP FTP SERVER ONCE THE MODEL IS RUNNING IN PARALLEL ON
>> THE NCEP CENTRAL COMPUTING SYSTEM IN MID APRIL. AT THAT TIME
>> THE PARALLEL DATA WILL BECOME AVAILABLE VIA THE FOLLOWING URL
>> /USE LOWERCASE/:
>> 
>> FTP://FTP.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PARA
>> 
>> DATA DELIVERY TIMING OF THE GFS WILL NOT BE IMPACTED BY THIS
>> IMPLEMENTATION.
>> 
>> NCEP ENCOURAGES ALL USERS TO ENSURE THEIR DECODERS ARE
>> FLEXIBLE AND ARE ABLE OF ADEQUATELY HANDLING CHANGES IN
>> CONTENT...PARAMETER FIELDS CHANGING ORDER...CHANGES IN THE
>> SCALING FACTOR COMPONENT WITHIN THE PRODUCT DEFINITION
>> SECTION /PDS/ OF THE GRIB FILES AND ANY VOLUME CHANGES WHICH
>> MAY OCCUR. THESE ELEMENTS MAY CHANGE WITH FUTURE NCEP MODEL
>> IMPLEMENTATIONS. NCEP WILL MAKE EVERY ATTEMPT TO ALERT USERS
>> TO THESE CHANGES PRIOR TO ANY IMPLEMENTATIONS.
>> 
>> IF YOU HAVE ANY QUESTIONS CONCERNING THESE CHANGES...PLEASE
>> CONTACT:
>> 
>> JOHN H. WARD
>> NCEP...GLOBAL MODELING BRANCH
>> CAMP SPRINGS MARYLAND
>> PHONE: 301-763-8000 X7185
>> EMAIL: JOHN.WARD at NOAA.GOV
>> OR
>> SHRINIVAS MOORTHI
>> NCEP...GLOBAL MODELING BRANCH
>> CAMP SPRINGS MARYLAND
>> PHONE: 301-763-8000 X7233
>> EMAIL: SHRINIVAS.MOORTHI at NOAA.GOV
>> 
>> NWS NATIONAL TECHNICAL IMPLEMENTATION NOTICES ARE ONLINE AT
>> /USE LOWERCASE/:
>> 
>>   HTTP://WWW.WEATHER.GOV/OS/NOTIF.HTM
>> 
>> $$
>> NNNN

Regards,

Kevin M Levey, MSc in Oceans and Atmospheric Sciences (University of Cape Town)
Director of Meteorological Operations
CustomWeather, Inc.
San Francisco, California, USA

"Taking the World by Storm!"

http://www.customweather.com
http://www.myforecast.com
http://www.1stweather.com

cell: 415-794-0411
work: 415-777-3566
email: klevey at customweather.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20100604/9d5b7054/attachment-0003.html 