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NOUS41 KWBC 161557
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PUBLIC INFORMATION STATEMENT...SERVICE CHANGE NOTICE 01-14
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
1100 AM EST FRI MAR 16 2001
TO: FAMILY OF SERVICES /FOS/ SUBSCRIBERS...NOAA WEATHER
WIRE SERVICE /NWWS/ SUBSCRIBERS...OTHER NATIONAL
WEATHER SERVICE /NWS/ CUSTOMERS AND PARTNERS...NWS
EMPLOYEES
FROM: ROBERT E. LIVEZEY
CHIEF...CLIMATE SERVICES DIVISION
SUBJECT: BASE PERIOD MEANS FOR CLIMATE OUTLOOKS TO BE UPDATED
FROM 1961-1990 MEANS TO 1971-2000 MEANS...EFFECTIVE
THURSDAY APRIL 12 2001
EFFECTIVE THURSDAY APRIL 12 2001...THE CLIMATE PREDICTION CENTER
/CPC/ WILL BEGIN USING THEIR 1971-2000 BASE PERIOD MEANS /BPM/
FOR TEMPERATURE...PRECIPITATION...AND 500 MILLIBAR HEIGHTS AS
REFERENCE IN THE CLIMATE OUTLOOKS LISTED BELOW. THE 1971-2000
BPMS WILL REPLACE THE 1961-1990 BPMS. THE NEW 1971-2000 BPMS WILL
BE AVAILABLE ON CPC/S WEB SITE AT HTTP://WWW.CPC.NCEP.NOAA.GOV
/USE LOWER CASE/ BY AROUND MARCH 23 2001.
THESE CPC BPMS ARE INTENDED FOR CPC/S CLIMATE OUTLOOKS ONLY. THE
OFFICIAL 1971-2000 CLIMATOLOGICAL NORMALS...ISSUED BY THE
NATIONAL CLIMATE DATA CENTER /NCDC/...WILL BE USED IN THE DAILY
AND MONTHLY STATION CLIMATE REPORTS ISSUED BY NWS WEATHER
FORECAST OFFICES /WFO/ STARTING JANUARY 1 2002. SEE QUESTIONS
AND ANSWERS BELOW THE PRODUCT LISTS FOR MORE INFORMATION
EXPLAINING CPC BPMS AND NCDC NORMALS. INFORMATIONAL NOTES ON
HEATING AND COOLING DEGREE DAYS FOLLOW THE QUESTIONS AND ANSWERS.
...LISTS OF CPC OUTLOOKS USING BPMS AS REFERENCE...
LIST 1 OF 4: 6- TO 10-DAY AND 8- TO 14-DAY OUTLOOK PRODUCTS
OUTLOOK CHARTS/ISSUED DAILY
WMO HEADING AWIPS ID AROUND 400 PM EASTERN TIME/
PEIY47 KWBC RBG96E 6- TO 10-DAY PRECIPITATION PROBABILITY
PNNT51 KWBC RBG96T 6- TO 10-DAY TEMPERATURE PROBABILITY
PHBV50 KWBC RBG96H 6- TO 10-DAY MEAN 500 MB HEIGHTS
PHNT50 KWNC RBG96C 6- TO 10-DAY MEAN 500 MB HEIGHT ANOMALY
PETT00 KWNC RBG98E 8- TO 14-DAY PRECIPITATION PROBABILITY
PTTU98 KWNC RBG98T 8- TO 14-DAY TEMPERATURE PROBABILITY
PHTT50 KWNC RBG98H 8- TO 14-DAY MEAN 500 MB HEIGHTS
PHTT51 KWNC RBG98C 8- TO 14-DAY MEAN 500 MB HEIGHT ANOMALY
NOTE: THE TEXTUAL PROGNOSTIC DISCUSSION FOR THE 6- TO 10-DAY AND
8- TO 14-DAY OUTLOOKS IS ISSUED MONDAY THROUGH FRIDAY
CONCURRENTLY WITH THE OUTLOOK CHARTS UNDER WMO HEADING
FXUS06 KWBC...PIL ID NMCPMDMRD...AND AWIPS ID PMDMRD.
- - - - - - - - - - - - - - - - - - - - - - - - - - - -
LIST 2 OF 4: MONTHLY /30-DAY/ OUTLOOK /EXCEPT HAWAII/...ISSUED
ONCE A MONTH ON A THURSDAY AROUND MID MONTH ABOUT 300 PM EASTERN
TIME.
MONTHLY OUTLOOK CHARTS
LEAD TIME PRECIPITATION TEMPERATURE
WMO HEADING AWIPS ID WMO HEADING AWIPS ID
0.5 MONTH PEIV98 KWNC RBG9ME PTIV98 KWNC RBG9MT
NOTE: A TEXTUAL PROGNOSTIC DISCUSSION FOR THE MONTHLY OUTLOOK IS
ISSUED CONCURRENTLY UNDER WMO HEADING OF FXUS07 KWBC...
PIL ID NMCPMD30D...AND AWIPS ID PMD30D.
- - - - - - - - - - - - - - - - - - - - - - - -
LIST 3 OF 4: SEASONAL /3-MONTH/ OUTLOOKS /EXCEPT
HAWAII/...ISSUED ONCE A MONTH ON A THURSDAY AROUND MID MONTH
ABOUT 300 PM EASTERN TIME.
SEASONAL OUTLOOK CHARTS
LEAD TIME PRECIPITATION TEMPERATURE
WMO HEADING AWIPS ID WMO HEADING AWIPS ID
0.5 MONTH PEIW01 KWBC RBGLPA PTIW01 KWBC RBGLTA
1.5 MONTH PEIW02 KWBC RBGLPB PTIW02 KWBC RBGLTB
2.5 MONTH PEIW03 KWBC RBGLPC PTIW03 KWBC RBGLTC
3.5 MONTH PEIW04 KWBC RBGLPD PTIW04 KWBC RBGLTD
4.5 MONTH PEIW05 KWBC RBGLPE PTIW05 KWBC RBGLTE
5.5 MONTH PEIW06 KWBC RBGLPF PTIW06 KWBC RBGLTF
6.5 MONTH PEIW07 KWBC RBGLPG PTIW07 KWBC RBGLTG
7.5 MONTH PEIW08 KWBC RBGLPH PTIW08 KWBC RBGLTH
8.5 MONTH PEIW09 KWBC RBGLPI PTIW09 KWBC RBGLTI
9.5 MONTH PEIW10 KWBC RBGLPJ PTIW10 KWBC RBGLTJ
10.5 MONTH PEIW11 KWBC RBGLPK PTIW11 KWBC RBGLTK
11.5 MONTH PEIW12 KWBC RBGLPL PTIW12 KWBC RBGLTL
12.5 MONTH PEIW13 KWBC RBGLPM PTIW13 KWBC RBGLTM
NOTE: A TEXTUAL PROGNOSTIC DISCUSSION FOR THE SEASONAL OUTLOOKS
IS ISSUED CONCURRENTLY UNDER WMO HEADING OF FXUS05 KWBC...
PIL ID NMCPMD90D...AND AWIPS ID PMD90D.
- - - - - - - - - - - - - - - - - - - - - - - - - - -
LIST 4 OF 4: HAWAIIAN MONTHLY AND SEASONAL OUTLOOKS...ISSUED
ONCE A MONTH ON A THURSDAY AROUND MID MONTH ABOUT 300 PM EASTERN
TIME.
THE TEXTUAL HAWAIIAN OUTLOOK/CLIMATOLOGICAL BULLETIN IS ISSUED
UNDER WMO HEADING FXHW40 KWBC...PIL ID NMCPMDHCO...AND
AWIPS ID PMDHCO.
- - - - - - - - - - - - - - - - - - - - - - - - - - -
...QUESTIONS AND ANSWERS ON CPC BPMS VS. NCDC NORMALS...
Q1 OF 3 - WHY DOES CPC COMPUTE THEIR OWN BASE PERIOD MEANS /BPMS/
RATHER THAN USE NCDC'S OFFICIAL NORMALS?
A: CPC COMPUTES SEVERAL STATISTICS (E.G. 500 MB HEIGHTS...
TERCILES OF TEMPERATURE AND PRECIPITATION OUTLOOK CLASSES
/ABOVE...NEAR NORMAL OR MEDIAN...AND BELOW/ FOR USE IN THE
CLIMATE OUTLOOKS WHICH ARE NOT PART OF THE NORMALS PROCESS AT
NCDC. ALSO...CPC COMPUTES AREAL INFORMATION FOR AREAS OTHER THAN
NCDC/S DESIGNATED CLIMATE REGIONS.
Q2 OF 3 - WHY DOES NCDC NEED MORE TIME TO PREPARE AND DISTRIBUTE
ITS OFFICIAL NORMALS THAN CPC DOES FOR ITS BPMS?
A: CPC DOES NOT REQUIRE THE PRECISION THAT NCDC DOES FOR THE
OFFICIAL NORMALS. CPC/S APPLICATION IS NOT AS SENSITIVE TO SUCH
FACTORS AS STATION MOVES AND INSTRUMENT CHANGES...WHICH ARE
VERY IMPORTANT TO OTHER USERS SUCH AS THE WEATHER DERIVATIVE
INDUSTRY AND UTILITIES. NCDC PROCESSES ALL DATA THROUGH
EXTENSIVE QUALITY CONTROL...CORRECTS DATA FOR DISCONTINUITIES
SUCH AS STATION MOVES AND INSTRUMENT CHANGES...AND FILLS IN
MISSING DATA.
Q3 OF 3 - WILL CPC USE NCDC NORMALS AFTER JANUARY 1 2002 TO
ADJUST ANY OF ITS BPMS?
A: CPC IS NOT EXPECTED TO MAKE ADJUSTMENTS TO ITS BPMS SINCE THE
SMALL DIFFERENCES WOULD GENERALLY BE INCONSEQUENTIAL FOR CPC/S
OUTLOOK PURPOSES. HOWEVER...IN THE UNLIKELY SITUATION THAT THIS
IS NOT THE CASE...ADJUSTMENTS WILL BE MADE.
...NOTES ON HEATING AND COOLING DEGREE DAYS /HDD AND CDD/...
NOTE 1 OF 2 - CPC/S WEEKLY POPULATION WEIGHTED HDD AND CDD
OUTLOOKS WILL USE NCDC/S 1971-2000 NORMAL HDD AND CDD INFORMATION
AND 2000 CENSUS DATA BEGINNING IN JANUARY 2002. THE CPC HDD/CDD
OUTLOOKS ARE ISSUED ONLY ON THE CPC WEB SITE AT /USE LOWER CASE/:
HTTP://WWW.CPC.NCEP.NOAA.GOV/PRODUCTS/ANALYSIS_MONITORING/CDUS/
DEGREE_DAYS/DDF_INDEX.HTML
USE OF NCDC 1971-2000 CDD/HDD NORMALS AND 2000 CENSUS DATA FOR
CPC POPULATION WEIGHTED HDD/CDD OUTLOOKS WILL BEGIN AT THE START
OF THE COOLING AND HEATING SEASONS /JANUARY 1 2002 AND
JULY 1 2002 RESPECTIVELY/. THIS AVOIDS DISCONTINUITIES IN USE OF
CDD/HDD NORMALS AND CENSUS DATA DURING THE HDD AND CDD SEASONS.
NOTE 2 OF 2 - LIKEWISE...USE OF NCDC 1971-2000 CDD/HDD NORMALS
FOR STATION DAILY AND MONTHLY CLIMATE REPORTS ISSUED BY WFOS WILL
BEGIN AT THE START OF THE COOLING AND HEATING SEASONS
/JANUARY 1 2002 AND JULY 1 2002 RESPECTIVELY/ TO AVOID
DISCONTINUITIES IN USE OF CDD/HDD NORMALS DURING THE HDD AND CDD
SEASONS.
IF YOU HAVE ANY QUESTIONS...EITHER SEND E-MAIL TO THE PUBLIC
LIAISON AT:
HTTP://WWW.NCEP.NOAA.GOV/MAIL_LIAISON.SHTML /USE LOWER CASE/
OR WRITE TO:
CLIMATE PREDICTION CENTER
OPERATIONS BRANCH - W/NP53
WORLD WEATHER BUILDING
5200 AUTH ROAD
CAMP SPRINGS MD 20746
THIS NOTICE AND OTHER SERVICE CHANGE NOTICES CAN BE FOUND ON THE
INTERNET AT /USE LOWER CASE/:
HTTP://WWW.NWS.NOAA.GOV/OM/NOTIF.HTM
END
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