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