NOUS41 KWBC 172005 AAA



Technical Implementation Notice 13-32 Amended

National Weather Service Headquarters Washington DC

400 PM Thu EDT Oct 17 2013


To:        Subscribers:

           -Family of Services

           -NOAA Weather Wire Service

           -Emergency Managers Weather Information Network


           Other NWS partners and employees


From:      Cynthia Abelman

           Chief, Aviation Services Branch


Subject:   Amended: Introduction of World Area Forecast System (WAFS)

           Upper Air Forecasts for FL410 (175 mb) effective

           November 13, 2013


Amended to change effective date to November 13, 2013


Effective Tuesday, November 13, 2013, at 1200 Coordinated

Universal Time (UTC), the NWS will introduce FL410 (Flight

level 41,000 ft) temperature, geopotential height, and wind

(u and v component of wind) to the WAFS Upper Air data set.


This additional data is being implemented in accordance with the

International Civil Aviation Organization (ICAO) WAFS Operations

Group seventh meeting.


This change will use the following new WMO Headers:


   Weather Element                  Header

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

175 mb (FL410) Height            YHX*18 KWBC

175 mb (FL410) Temperature       YTX*18 KWBC

175 mb (FL410) U Wind            YUX*18 KWBC

175 mb (FL410) V Wind            YVX*18 KWBC


Where  * is replaced with a letter referencing the

forecast valid time from issuance

* =   C - 06 hour forecast

* =   D - 09 hour forecast

* =   E - 12 hour forecast

* =   F - 15 hour forecast

* =   G - 18 hour forecast

* =   H - 21 hour forecast

* =   I - 24 hour forecast

* =   J - 27 hour forecast

* =   K - 30 hour forecast

* =   L - 33 hour forecast

* =   M - 36 hour forecast


In support of the World Area Forecast System, the NWS (WAFC)

Washington provides global gridded forecasts of upper wind and

temperature data covering Flight Levels FL050-530, tropopause

heights and temperature, maximum wind (height, speed, direction),

turbulence, icing, and cumulonimbus clouds based on output from

the Global Forecast System Numerical Weather Model. This data can

be used in flight planning systems to optimize flights routes or

to generate a range of charts, such and wind and temperature

charts, cross sections, etc.


The aforementioned gridded products are produced four times

daily, and are available in GRIB2 format on the WAFS Internet

File System (WIFS). WIFS is available to registered users at:


Due to the government shutdown, this notice is being sent with

less than the required notification time. NWS does not have the

ability to change the effective date of this WAFC change.


For technical questions, and support in registering a user

account at the WIFS website, or downloading and accessing the

GRIB2 data, contact:


Ryan Solomon

Aviation Weather Center

Kansas City, MO 64153

Phone: 816-584-72048   



If you have any questions about this change, or the WAFS Global

Grids data set, please contact:


Matt Strahan

Chief, International Operations Branch

Aviation Weather Center/WAFC Washington

Kansas City, MO 64153

Phone: 816-584-7204   



National Technical Implementation Notices are online at: