422
NOUS41 KWBC 091850
PNSWSH
TECHNICAL IMPLEMENTATION NOTICE 04-09...RESENT
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
155 PM EST TUE MAR 9 2004
TO: FAMILY OF SERVICES /FOS/ SUBSCRIBERS...NOAA WEATHER
WIRE SERVICE /NWWS/ SUBSCRIBERS...EMERGENCY MANAGERS
WEATHER INFORMATION NETWORK /EMWIN/ SUBSCRIBERS...
NOAAPORT SUBSCRIBERS...OTHER NATIONAL WEATHER SERVICE
/NWS/ CUSTOMERS AND PARTNERS...NWS EMPLOYEES
FROM: PAUL HIRSCHBERG
CHIEF...SCIENCE PLANS BRANCH
OFFICE OF SCIENCE AND TECHNOLOGY /OST/
SUBJECT: CHANGES IN GLOBAL FORECAST SYSTEM /GFS/ MODEL OUTPUT
STATISTICS /MOS/ GUIDANCE FOR TOTAL SKY COVER...
CEILING HEIGHT...AND VISIBILITY...EFFECTIVE MAY 18 2004
RESENT DUE TO POSSIBLE GARBLING OF ORIGINAL MESSAGE...WHICH WAS
TRANSMITTED MARCH 4 2004
NOTE...THE FOLLOWING CHANGES HAVE NO IMPACT ON NOAA WEATHER
WIRE SUBSCRIBERS
ATTENTION USERS OF THE MODEL OUTPUT STATISTICS /MOS/ GUIDANCE:
ON TUESDAY...MAY 18 2004...WITH THE 1200 COORDINATED UNIVERSAL
TIME /UTC/ MODEL CYCLE...THE NWS WILL CHANGE THE CONTENT OF THE
GLOBAL FORECAST SYSTEM /GFS/ MODEL OUTPUT STATISTICS /MOS/
GUIDANCE. THE DEFINITION OF CATEGORIES OF TOTAL SKY COVER AND
CEILING HEIGHT WILL BE MODIFIED TO DISTINGUISH BETWEEN FEW /FW/
AND SCATTERED /SC/ CLOUDS AND BETWEEN CEILINGS OF 1000-1900 FT
AND 2000-3000 FT. DEFINITIONS OF THE CATEGORICAL VISIBILITY
GUIDANCE WILL ALSO BE MODIFIED.
THE NEW SKY COVER CATEGORIES WILL BE AS FOLLOWS:
CL = CLEAR
FW = > 0 to 2 OCTAS OF TOTAL SKY COVER
SC = > 2 to 4 OCTAS OF TOTAL SKY COVER
BK = > 4 to < 8 OCTAS OF TOTAL SKY COVER
OV = 8 OCTAS OF TOTAL SKY COVER OR TOTALLY OBSCURED
THE NEW CATEGORICAL NUMBERS FOR CEILING HEIGHT WILL BE AS
FOLLOWS:
1 = < 200 FT
2 = 200 TO 400 FT
3 = 500 TO 900 FT
4 = 1000 TO 1900 FT
5 = 2000 TO 3000 FT
6 = 3100 TO 6500 FT
7 = 6600 TO 12000 FT
8 = > 12000 FT OR UNLIMITED.
DEFINITIONS OF THE CATEGORICAL VISIBILITY GUIDANCE WILL BE
CHANGED TO THE FOLLOWING:
1 = < 1/2 MI
2 = 1/2 MI TO < 1 MI
3 = 1 TO < 2 MI
4 = 2 TO < 3 MI
5 = 3 TO 5 MI
6 = 6 MI
7 = > 6 MI
TABLE 1. COMMUNICATION IDENTIFIERS FOR THE GFS-BASED MOS TEXT
PRODUCTS WHICH WILL BE MODIFIED. THE AWIPS IDS ARE
MAVXXX...WHERE THE FINAL XXX DENOTES THE GEOGRAPHIC REGION FOR
WHICH THE GUIDANCE IS VALID.
WMO HEADING AWIPS ID GEOGRAPHIC REGION
FOPA20 KWNO MAVPA0 PACIFIC ISLANDS
FOUS21 KWNO MAVNE1 NORTHEAST CONUS
FOUS22 KWNO MAVSE1 SOUTHEAST CONUS
FOUS23 KWNO MAVNC1 NORTH CENTRAL CONUS
FOUS24 KWNO MAVSC1 SOUTH CENTRAL CONUS
FOUS25 KWNO MAVRM1 ROCKY MOUNTAIN CONUS
FOUS26 KWNO MAVWC0 WEST COAST CONUS
FOAK37 KWNO MAVAJK SOUTHEAST ALASKA /JUNEAU/
FOAK38 KWNO MAVAFC CENTRAL ALASKA /ANCHORAGE /
FOAK39 KWNO MAVAFG NORTHERN ALASKA /FAIRBANKS/
A TECHNICAL DESCRIPTION OF THE MODIFIED SHORT-RANGE GFS MOS
FORMAT CAN BE FOUND AT THE URL LISTED BELOW /USE LOWER CASE
LETTERS/:
HTTP://WWW.NWS.NOAA.GOV/MDL/SYNOP/TPB/GFSMSG2004T0012.PDF
HTTP://WWW.NWS.NOAA.GOV/MDL/SYNOP/TPB/GFSMSG2004T0618.PDF
LINKS TO THESE PRODUCTS...ALONG WITH DESCRIPTIONS...CAN BE FOUND
AT /USE LOWER CASE LETTERS/:
HTTP://WWW.NWS.NOAA.GOV/MDL/SYNOP/PRODUCTS.SHTML
NO CHANGES WILL BE MADE TO THE BUFR /GRIDDED BINARY/ MOS MESSAGES
AT THIS TIME.
IF YOU HAVE ANY QUESTIONS ABOUT THESE CHANGES TO THE MOS GUIDANCE
SYSTEM...PLEASE CONTACT:
PAUL DALLAVALLE
MDL/SILVER SPRING MARYLAND
PHONE: 301-713-0023 EXT. 135
E-MAIL: PAUL.DALLAVALLE@xxxxxxxx
THIS AND OTHER NWS TECHNICAL IMPLEMENTATION NOTICES ARE AVAILABLE
ONLINE AT /USE LOWER CASE LETTERS/:
HTTP://WWW.NWS.NOAA.GOV/OS/NOTIF.HTM
$$
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