NOCN02 CWAO 171830
GENOT FAX NO. 011

AS OF JUNE 17 1997 AT 1200 UTC,  THE CANADIAN METEOROLOGICAL CENTER
WILL IMPLEMENT AN ERROR-FEEDBACK MECHANISM ON THE MAXIMUM/MINIMUN 
TEMPERATURE FORECASTS AT 160 CANADIAN STATIONS FOR DAYS ONE TO DAY 5
BASED ON THE OPERATIONAL CANADIAN GLOBAL MODEL. THIS SYSTEM HAS
BEEN TESTED OVER SEVERAL MONTHS FROM OCTOBER 1996 TO MAY 1997
INCLUSIVE. OVER ALL THE BIAS OF THE FORECASTS WAS REDUCED TO ZERO 
OVER THE TEST PERIOD AND THE PERCENTAGE IMPROVEMENT OVER CLIMATOLOGY
OF THE FORECASTS HAS BEEN INCREASED BY AT LEAST TWO POINTS AT ALL 
PROJECTION RANGES. OVER SOME REGIONS, THE ROOT MEAN SQUARE ERROR IS 
REDUCED BY 0.5 DEGREES CELSIUS AND THE PERCENT IMPROVEMENT OVER 
CLIMATOLOGY INCREASED BY AS MUCH AS 8 POINTS. THE MAXIMIM/MINIMUM 
TEMPERATURE FORECASTS AFFECTED ARE THOSE IN THE BULLETINS WHOSE 
HEADERS ARE: FMCN31 TO FMCN38 CWAO AND FXCN07 CWAO1 TO CWAO12.


A COMPTER DE 1200 UTC LE 17 JUIN 1997,  LE CENTRE METEOROLOGIQUE 
CANADIEN METTRA EN OEUVRE UN SYSTEME DE RETRO-ACTION D'ERREUR SUR 
LES PREVISIONS DES TEMPERATURES MAXIMALES ET MINIMALES A 160 STATIONS
CANADIENNES BASEES SUR LE MODELE GLOBAL CANADIEN OPERATIONNEL.
CE SYSTEME A ETE EVALUE PENDANT PLUSIEURS MOIS, D'OCTOBRE 1996 A 
MAI 1997 INCLUSIVEMENT. EN GENERAL L'ERREUR MOYENNE DES PREVISIONS
A ETE REDUITE A ZERO PENDANT LA PERIODE D'EVALUATION ET LE 
POURCENTAGE D'AMELIORATION PAR RAPPORT A LA CLIMATOLOGIE A ETE 
AUGMENTE D'AU MOINS DEUX POINTS A TOUS LES TEMPS DE PROJECTION. 
DANS QUELQUES REGIONS L'ERREUR QUADRATIQUE MOYENNE EST REDUITE DE 
0.5 DEGRE CELSIUS AND LE POURCENTAGE D'AMELIORATION SUR LA 
CLIMATOLOGIE AUGMENTE DE 8 POINTS. LES TEMPERATURES 
MAXIMALES/MINIMALES CONCERNEES SONT CELLES INCLUSES DANS LES 
BULLETINS DONT LES ENTETES SONT: FMCN31 A FMCN38 CWAO ET 
FXCN07 CWAO1 A CWAO12.

MCBEAN/ADMA/TORONTO