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NOUS40 KWBC 101527
FOS/NOAAPORT NOTICE NO. 1218 APRIL 10... 1998
PART 1 OF A 2 PART MESSAGE
TO FAMILY OF SERVICES SUBSCRIBERS
NOAAPORT USERS
FROM DOUGLAS F. HESS
CHIEF... SYSTEMS INTEGRATION DIVISION
SUBJECT NOTIFICATION OF CORRECTIONS TO NATIONAL
WEATHER SERVICE /NWS/ PRACTICES FOR
ENCODING UPPER-AIR DATA
CODED MESSAGES FOR SOUNDINGS DISSEMINATED FROM NWS
UPPER-AIR STATIONS USING THE MICROCOMPUTER AUTOMATIC
RADIO-THEODOLITE /MICROART/ SYSTEM ARE NOT FULLY COMPLIANT
WITH WORLD METEOROLOGICAL ORGANIZATION /WMO/ STANDARDS.
THE WMO ABBREVIATED HEADING AND PLACEMENT OF THE WMO
STATION INDEX NUMBER IN THE CODED MESSAGES ARE INCORRECT.
FURTHERMORE A REQUIRED CLOUD OBSERVATION TAKEN AT THE
TIME THE UPPER-AIR SOUNDING BEGAN IS MISSING FROM THE REPORT.
UPPER-AIR REPORTS RECEIVED AT THE NWS TELECOMMUNICATION
GATEWAY /NWSTG/ ARE PROCESSED FOR DISTRIBUTION ON THE GLOBAL
TELECOMUNICATION SYSTEM /GTS/. THE ABBREVIATED HEADING AND
PLACEMENT OF THE STATION INDEX NUMBER FROM ALL MICROART
REPORTS ARE CORRECTED BY NWSTG AND SENT TO GTS. HOWEVER
CLOUD INFORMATION IS NOT ADDED TO THE REPORTS SINCE SUCH
INFORMATION IS NOT AVAILABLE AT NWSTG.
THE NWS WILL CORRECT THE MICROART SOFTWARE SO UPPER-AIR
REPORTS HAVE THE CORRECT ABBREVIATED HEADING AND REQUIRED
CLOUD INFORMATION. PART 2 OF THIS MESSAGE HAS DETAILED
INFORMATION ON CURRENT NWS PRACTICES AND THE CORRECT
FORMS WHICH NWS PLANS TO IMPLEMENT. SINCE CORRECT
PLACEMENT OF THE STATION INDEX NUMBER IS CURRENTLY BEING
PERFORMED BY NWSTG NO CHANGE WILL BE MADE AT THIS TIME.
HOWEVER WITHIN THE NEXT FEW YEARS NWS PLANS TO REPLACE
THE MICROART SYSTEMS WITH MORE MODERN EQUIPMENT THAT WILL
PROVIDE DATA FULLY COMPLIANT WITH WMO STANDARDS.
END
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PART 2 OF A 2 PART MESSAGE
TO FAMILY OF SERVICES SUBSCRIBERS
NOAAPORT USERS
FROM DOUGLAS F. HESS
CHIEF... SYSTEMS INTEGRATION DIVISION
SUBJECT NOTIFICATION OF CORRECTIONS TO NATIONAL
WEATHER SERVICE /NWS/ PRACTICES FOR
ENCODING UPPER-AIR DATA
THE NWS PLANS TO CORRECT THE ABREVIATED HEADING AND INCLUDE
CLOUD INFORMATION IN ALL MICROART UPPER-AIR REPORTS NO EARLIER
THAN OCTOBER 1 1998. YOU WILL BE NOTIFIED AT LEAST 60 DAYS
PRIOR TO THE ACTUAL IMPLEMENTATION DATE. PRIOR TO IMPLEMENTATION
NWS WILL CONDUCT A TEST WHERE CORRECTED
CODED MESSAGES FROM SELECTED UPPER-AIR STATIONS WILL BE DISSEMINATED.
THIS TEST WILL ENSURE THAT OPERATIONAL DATA USERS CAN RETRIEVE
THESE DATA WITHOUT DIFFICULTY.
ANY COMMENTS OR QUESTIONS SHOULD BE DIRECTED TO WILLIAM H.
BLACKMORE BEFORE JUNE 1. HE CAN BE CONTACTED AT
301-713-0722 X170 OR ON E-MAIL WILLIAM.BLACKMORE NOAA.GOV.
CURRENT NWS PRACTICES FOR ENCODING WMO UPPER AIR REPORTS AND
THE CORRECT FORM NWS WILL IMPLEMENT
WMO ABBREVIATED HEADING
CURRENT NWS PRACTICE
NWS USES THE WMO ABBREVIATED HEADINGS FORM TTAAI CCCC WHERE
TT = DATA TYPE DESIGNATOR /NWS USES UJ INCORRECTLY/
AA = GEOGRAPHICAL DESIGNATOR /E.G. US PA ETC./
I = VALUE THAT DIFFERENTIATES BETWEEN TWO OR MORE BULLETINS
CONTAINING DATA IN THE SAME CODE ORIGINATES FROM THE SAME
GEOGRAPHICAL AREA AND HAS THE SAME ORIGINATING CENTER.
CCCC = INTERNATIONAL FOUR-LETTER LOCATION INDICATOR OF THE
STATION ORIGINATING OR COMPILING THE BULLETIN.
CORRECT FORM
REFERENCE WMO NO. 386 MANUAL ON THE GLOBAL TELECOMMUNI- CATIONS
SYSTEM VOL. I PART II ATTACHMENTS 4 AND 6.
THE CORRECT FORM IS TTAAII CCCC WHERE
TT = DATA TYPE DESIGNATOR /E.G. US = TEMP PART A
UK = TEMP PART B ETC./
II = SAME AS CURRENT NWS PRACTICE BUT SHOULD ALWAYS BE TWO DIGITS.
VALUES OF II LESS THAN 10 SHALL BE PRECEDED BY ZERO /E.G. TTAA01/.
CLOUD INFORMATION
CURRENT NWS PRACTICE
A COMPLETE SURFACE WEATHER OBSERVATION IS RECORDED NEAR THE
START OF THE UPPER AIR SOUNDING BY NWS OBSERVERS BUT
THE CLOUD PORTION OF THE OBSERVATION IS NOT INCLUDED IN THE
CODED MESSAGE.
CORRECT FORM
REFERENCE WMO NO. 306 MANUAL ON CODES VOL 1.1
SECTIONS A AND B.
A CODE GROUP ON CLOUD INFORMATION SHOULD BE INCLUDED IN THE
CODED MESSAGE. IT BELONGS BETWEEN THE 31313 AND 51515
GROUPS IN THE PART B OR TTBB MESSAGE AND SHOULD APPEAR
AS FOLLOWS
41414 NHCLHCMCH
WHERE
NH = AMOUNT OF ALL CL CLOUD PRESENT OR IF NO CL IS PRESENT
THE AMOUNT OF ALL CM CLOUD PRESENT IN EIGHTHS OF CLOUD COVER.
CODE FIGURES 0 THROUGH 9 AND / ARE USED TO DEFINE CLOUD TYPES
AS DEFINED BY A CODE TABLE.
CL = TYPE OF LOW CLOUD PRESENT.
H = HEIGHT ABOVE SURFACE OF THE LOWEST CLOUD SEEN AS DEFINED BY
A CODE TABLE.
CM = TYPE OF MID-LEVEL CLOUD PRESENT.
CH = TYPE OF HIGH-CLOUD PRESENT.
END
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