NOUS41 KWBC 121623 AAA



Technical Implementation Notice 13-16 Amended

National Weather Service Headquarters Washington DC

1223 PM EDT Fri Jul 12 2013


To:       Subscribers:

          -Family of Services

          -NOAA Weather Wire Service

          -Emergency Managers Weather Information Network


          Other NWS Partners, Users and Employees


From:     Timothy McClung

          Science Plans Branch Chief

          Office of Science and Technology


Subject:  Amended to postpone the upgrade date to July 23, 2013

          due to the delay in the transition of the NCEP

          production suite to the WCOSS supercomputer.


Effective on or about Tuesday, July 23, 2013, beginning with the

1200 Coordinated Universal Time (UTC) run, the National Centers

for Environmental Prediction (NCEP) will upgrade the HYSPLIT

modeling system including smoke, dust and volcanic ash.


The NOAA Air Resources Laboratory HYSPLIT subversion number 339

will be implemented as NCEP version 7.0.0 on NCEP's new Weather

and Climate Operational Supercomputing System (WCOSS), scheduled

to become the operational machine on July 23, 2013.  A separate

TIN will be issued announcing the operational switch to the

Weather and Climate Operational Supercomputing System (WCOSS)

system. In the event that switch date is changed, this TIN will

be modified to reflect that change in implementation date.


Forecasts from the updated HYSPLIT model will be made available

through a parallel feed from WCOSS starting around June 19,

2013. The smoke and dust HYSPLIT GRIB products from the parallel

feed are disseminated via the NCEP website:


and the products will be displayed through NCEP's website:


Current operational HYSPLIT model will continue providing

forecasts through NCEP Central Computing System (CCS) until the

WCOSS machine goes live on July 23, 2013.  At that time updated

WCOSS smoke and dust predictions will be distributed through


and displayed at


The scientific enhancements include the following:


-- Improved wet removal by reducing in-cloud particle wet

   removal coefficient, allowing wet removal to occur only when

   both precipitation and clouds are defined in the same grid

   cell and turned off precipitation field spatial interpolation

-- Revised horizontal puff dispersion rate to be more consistent

   with particle dispersion

-- Set Kanthar-Clayson vertical mixing parameterization as


-- Relaxed maximum plume rise limits

-- Modified fires pre-processer for daily emission cycling


The model has been tested with these updates for all HYSPLIT

applications at NCEP. The test showed generally similar results,

except for simulations of the wet deposition from the Fukushima

nuclear power plant incident of 2011, in which significant

improvements occurred.   


There are no changes to existing products or their contents. 

More details about the HYSPLIT are available at:


For questions regarding these updated predictions, contact:


Ivanka Stajner


Silver Spring, MD 20910

301 713 9001 x 185


NWS National Technical Implementation Notices are online at: