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NOUS41 KWBC 121749
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PUBLIC INFORMATION STATEMENT...SERVICE CHANGE NOTICE 00-43
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
145 PM EDT WED APR 12 2000
TO: NATIONAL WEATHER SERVICE EMPLOYEES...NOAAPORT
SUBSCRIBERS... NWS EMPLOYEES...AND OTHER NWS CUSTOMERS
FROM: ROBERT E. LIVEZEY
CHIEF...CLIMATE SERVICES DIVISION
SUBJECT: NEW APPARENT TEMPERATURE PROBABILITY OUTLOOKS FOR
HEAT...EFFECTIVE JUNE 1 2000
ON THURSDAY...JUNE 1 2000...THE CLIMATE PREDICTION CENTER /CPC/
WILL START PROVIDING APPARENT TEMPERATURE PROBABILITY OUTLOOKS
FOR HEAT. THE OUTLOOKS WILL BE ISSUED DAILY AROUND 4:00 PM
EASTERN LOCAL TIME. THE OUTLOOKS WILL EMPHASIZE DAILY MEAN
APPARENT TEMPERATURE RATHER THAN MAXIMUM APPARENT
TEMPERATURE...ALTHOUGH CPC ALSO WILL PROVIDE THE EXPECTED VALUE
OF THE MAXIMUM AT APPROXIMATELY 200 LOCATIONS.
BECAUSE HEALTH RISKS VARY ENORMOUSLY FROM AREA TO AREA...CPC WILL
ISSUE FORECASTS OF PROBABILITY ANOMALIES FOR APPARENT
TEMPERATURES EXCEEDING THREE DIFFERENT THRESHOLDS. THESE WILL BE
OVERLAID ON ISOLINES OF THE CLIMATOLOGICAL NORMAL PROBABILITIES.
CPC CHOSE THE THRESHOLD TEMPERATURE VALUES BASED ON WHEN
CUMULATIVE EXPOSURE WOULD BE LIKELY TO CAUSE SIGNIFICANT HEALTH
RISKS FOR A NUMBER OF THE MOST VULNERABLE CITIES.
IN ADDITION...BECAUSE VULNERABILITY INCREASES WITH DURATION OF
THE HEAT WAVE...RISKS FOR EXCEEDING THE LOWER THRESHOLDS ARE FOR
DURATIONS LONGER THAN ONE DAY. THESE NEW PRODUCTS WILL CONSIST OF
MAPS OF PROBABILITY ANOMALIES OF DAILY MEAN APPARENT TEMPERATURE
FOR THRESHOLDS EQUAL TO OR GREATER THAN 85F... 90F... OR 95F FOR
EACH OF THE 3-7-... 6-10-... AND 8-14-DAY FORECAST PERIODS. THE
FORECASTS WILL BE FOR DIFFERENT MINIMUM NUMBERS OF DAYS WITHIN
THE 5 OR 7 DAY PERIOD OF THE FORECAST - NAMELY 3...2 AND 1 DAYS -
RESPECTIVELY - WHEN THE THRESHOLDS ARE EQUALED OR EXCEEDED.
MORE SPECIFICALLY...FOR THE 3-7-... 6-10- AND 8-14-DAY OUTLOOK
PERIODS - THE NEW PRODUCTS PREDICT THE PERCENT CHANCE - IN EXCESS
OF THE CLIMATOLOGICAL CHANCE - OF EQUALING OR EXCEEDING THE
FOLLOWING CRITERIA:
A. DAILY AVERAGE APPARENT TEMPERATURE EQUAL TO OR GREATER THAN
85F THREE OR MORE DAYS IN THE FORECAST PERIOD
B. DAILY AVERAGE APPARENT TEMPERATURE EQUAL TO OR GREATER THAN
90F TWO OR MORE DAYS IN THE FORECAST PERIOD
C. DAILY AVERAGE APPARENT TEMPERATURE EQUAL TO OR GREATER THAN
95F ONE OR MORE DAYS IN THE FORECAST PERIOD
THE WMO HEADINGS AND AWIPS IDENTIFIERS FOR THE NINE CHARTS ARE AS
FOLLOWS:
AV. APPARENT TEMP. 3-7 DAY 6-10 DAY 8-14 DAY
CRITERIA A PTAM90 KWNC PTAS90 KWNC PTAT90 KWNC
/85F+ FOR 3+DAYS/ RBGHI1 RBGHI4 RBGHI7
CRITERIA B PTAM95 KWNC PTAS95 KWNC PTAT95 KWNC
/90F+ FOR 2+DAYS/ RBGHI2 RBGHI5 RBGHI8
CRITERIA C PTAM00 KWNC PTAS00 KWNC PTAT00 KWNC
/95F+ FOR 1+DAY/ RBGHI3 RBGHI6 RBGHI9
NOTE - THE NUMBERS WITHIN THE WMO HEADINGS DO NOT COINCIDE WITH
THE APPARENT TEMPERATURE THRESHOLDS.
THESE NINE CHARTS WILL BE ISSUED OVER AWIPS...NOAAPORT...AND THE
CPC INTERNET SITE - HTTP://WWW.CPC.NCEP.NOAA.GOV - USE LOWER CASE
FOR FURTHER INFORMATION...CONTACT
NOAA/NWS
CLIMATE PREDICTION CENTER - W/NP51
5200 AUTH RD.
CAMP SPRINGS MD 20746-4304
OR E-MAIL CPC THROUGH THEIR WEB SITE.
THIS AND OTHER NOTIFICATIONS ARE ON THE INTERNET AT:
WWW.NWS.NOAA/GOV/OM/NOTIF.HTM /USE LOWER CASE/
END
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