INT - DATA MGT MESSAGE 10-98.5

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: INT - DATA MGT MESSAGE 10-98.5
• From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx>
• Date: 10/13/98 9:55 AM

Author:  Fred Branski at W-OSO2
     
     
     The attached message is a status update on the ice pellet reporting 
     code change from PE to PL. A notice was sent earlier today on our 
     communications lines as well.  It is also posted to the SOC Change 
     Notices web page at the following URL (and is also shown below).
     
     http://www.nws.noaa.gov/oso/notices/notices.shtml. 
     
     Cheers, Fred
     
     Fred Branski
     National Weather Service
     Senior Data Manager, W/OSO21
     
     Phone:    (301) 713-0864 ext 146
     Fax:      (301) 713-1409
     E-mail:   Fred.Branski@xxxxxxxx
     
     
NOXX01 KWBC 131348
DATA MGT MESSAGE 10-98.5
     
THE LATEST UPDATE FROM THE U.S. NATIONAL WEATHER SERVICE ON THE 
ICE PELLET REPORTING CODE CHANGE IS AVAILABLE ON THE SYSTEMS 
OPERATIONS CENTER CHANGE NOTICES WEB PAGE.
     
THE URL IS LISTED BELOW.
     
NOTE THE URL SHOULD BE TYPED IN ALL LOWER CASE.
     
HTTP TO  WWW.NWS.NOAA.GOV/OSO/NOTICES/NOTICES.SHTML
     
NETWORK MONITORING AND ANALYSIS BRANCH 
SYSTEMS OPERATIONS CENTER
RTH WASHINGTON SENDS
     
     
     DATE: October 1, 1998
     
     MEMORANDUM FOR:  All users of METAR/SPECI observations And TAF
        Messages
     
     FROM:                             OSO14x1 - Dave Mannarano
                                              Ice Pellet Implementation
                                                Manager
     
     SUBJECT:                        USA and International Code Change For
                                        Ice Pellets
     
     
        Effective 0000UTC, November 5, 1998 the Aviation Routine Weather 
     Report/Aviation Selected Special Weather (METAR/SPECI) code formats
used in the United States of America (USA) for reporting ice pellets will 
change from "PE" to "PL."  New USA observing policy/procedures will 
require that only "PL" be used to encode ice pellets starting
November 5, 1998.  This change applies to all manual observing stations and
automated observing stations where human augmentation is provided for reporting
ice pellets.  It does not apply to unstaffed automated observing stations 
which do not/cannot report ice pellets.
     
        The dual capability to encode ice pellets as either "PE" or "PL"
is  being implemented at 144 staffed Automated Surface Observing System
(ASOS) locations.  Although these locations will have the capability to
transmit ice pellets as "PL," they are instructed to only use "PE" until
November 5, 1998.  Furthermore, although the implementation on November 5, 1998
is planned to be a fully coordinated "turn-key" event, there may still
be some observers who did not "get the word" and may incorrectly continue to
use the obsolete "PE" code after 0000 UTC, November 5, 1998.  All 
delinquencies will be corrected as soon as possible.  As a precaution, users 
with 
automated decoders are urged to take appropriate steps now to
recognize both "PE" and "PL" in the METAR/SPECI code.
     
        Concurrent with the METAR/SPECI ice pellet code conversion (PE to
PL) at 0000 UTC, November 5, 1998, the USA will also convert the Terminal 
Aerodrome Forecast (TAF) code format for ice pellets from "PE" to
"PL."  
     All USA TAFS which are valid on or after 0000 UTC, November 5, 1998
will use PL when referring to ice pellets.  Again, as a precaution, users
with automated decoders are urged to take appropriate steps now to
recognize both "PE" and "PL" in the TAF code as well.
     
     2
        In addition, effective 0000 UTC, November 5, 1998 "PL" will be
used to indicate ice pellets in USA SIGMETs, Convective SIGMETs, domestic and 
international Area Forecasts, and Center Weather Service Unit
products (Center Weather Advisories and Meteorological Impact Statements).
     
        The ice pellet code change from PE to PL is a world-wide change.
The ICAO Council in March 1998 adopted Amendment 71 to ICAO annex 3, - 
 Meteorological Service for International Air Navigation Standards,
and recommended practices which detail the aviation requirements for 
 meteorological services.  ICAO Annex 3 is identical to WMO Technical 
 Regulations (C.3.1).  These international documents were brought in
line  when WMO's Executive Council adopted these changes in June 1998.
Although this is an international change, some member states may file
exceptions and continue to report PE.  It is for this reason that all decoders 
and 
computer databases which use or exchange international meteorological
data be modified to recognize both PE and PL as legitimate indicators for
ice pellets.
     
        Additional updated notices will be provided as the ice pellet code 
change implementation date approaches.  If you have any questions
about this change please call me at (301) 713-2093 or E-MAIL me at 
David.Mannarano@xxxxxxxx.
     
     c:/wp51/usered/pepl_06
     W/OSO14:DM 10/1/98