PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EDT THU AUG 12 2004
 
6 TO 10 DAY OUTLOOK FOR AUGUST 18 - 22 2004
         .         .         .         .         .         .         .
TODAYS 500-HPA GEOPOTENTIAL HEIGHT FORECASTS ARE IN GOOD AGREEMENT
OVER THE NORTH AMERICAN VICINITY AND ADJACENT OCEANIC AREAS FOR THE
6-10 DAY PERIOD...WITH THE EXCEPTION OF THE OPERATIONAL ECMWF WHICH
IS QUITE UNLIKE THE OTHER SOLUTIONS AND WILL BE BRIEFLY DISCUSSED 
LATER.  THE PRIMARY CIRCULATION FEATURES EXPECTED FOR THIS 6-10 DAY
PERIOD INCLUDE A RIDGE EXTENDING FROM THE GREAT BASIN AND ROCKIES
NORTHWESTWARD THROUGH INTERIOR BRITISH COLUMBIA AND ACROSS MOST OF
ALASKA...AND A MEAN TROUGH OVER THE EASTERN LOWER 48 STATES WHICH 
IS PART OF A FULL LATITUDE TROUGH STRETCHING FROM NEAR THE NORTH POLE
ACROSS ALL OF EASTERN NORTH AMERICA.  THERE ARE DIFFERENCES BETWEEN
MODEL RUNS AS TO THE PLACEMENT OF THIS MEAN TROUGH...WITH SOME FORE-
CASTING THE AXIS NEAR THE EAST COAST AND OTHERS AS FAR WEST AS THE 
MISSISSIPPI RIVER.  THE CONSENSUS POSITION HOWEVER CONTINUES TO BE
OVER THE OHIO VALLEY AND APPALACHIANS.  AS NOTED ABOVE...TODAYS ECMWF
SOLUTION IS VERY DIFFERENT FROM ITS GFS-RELATED COUNTERPARTS.  PROB-
LEMS ARISE EARLY ON...WITH HURRICANE CHARLEYS POSITION BEING INITIAL-
IZED SOMEWHAT SOUTH OF ITS CURRENT LOCATION...AND ULTIMATELY TAKING 
THE STORM NORTHWESTWARD TO THE TEXAS COAST.  THE ECMWF ALSO HAS FAST
ZONAL FLOW ACROSS THE NORTHWESTERN U.S. AND SOUTHWESTERN CANADA...
SEVERING THE WESTERN RIDGE IN HALF.  THE UNLIKELINESS OF THE ECMWF 
SCENARIO HAS RESULTED IN IT BEING DISCOUNTED TODAY.

INSPECTION OF 0Z GFS MODEL ERRORS OVER THE PAST WEEK (AND TO A LES-
SER EXTENT THE PAST MONTH) REVEALS THAT THIS MODEL HAS BEEN UNDER-
FORECASTING 500-HPA HEIGHTS OVER ALASKA...WHILE OVER-FORECASTING 
HEIGHTS OVER THE NORTHEASTERN U.S..  THIS IS CONSISTENT WITH THE 
COOLER TEMPERATURES EXPERIENCED LATELY ACROSS THE NORTHEAST...AND
THE CONTINUING ANOMALOUS WARMTH OVER ALASKA.  THE STABILITY OF THESE
BIASES OVER THE PAST MONTH SHOWS THAT THE PRESENT CIRCULATION REGIME
IS RECURRING FREQUENTLY...DESPITE BEING PUNCTUATED TEMPORARILY BY 
SHORT-LIVED PATTERN CHANGES.

HURRICANE CHARLEY IS PRESENTLY LOCATED OVER THE NORTHWESTERN CARIB-
BEAN SEA.  FORECAST PROJECTIONS FROM THE NATIONAL HURRICANE CENTER
(NHC) TAKE CHARLEY ACROSS WESTERN CUBA AND NEAR THE OUTERMOST FLOR-
IDA KEYS IN 18 TO 24 HOURS.  ALTHOUGH THE STATE MOST LIKELY TO EXPER-
IENCE LANDFALL IS FLORIDA...THE CENTRAL GULF COAST STATES SHOULD NOT
LET DOWN THEIR GUARD IN CASE CHARLEY ASSUMES A MORE WESTERN TRAJEC-
TORY.   PEOPLE ARE URGED TO MONITOR THE PROGRESS OF THIS STORM BY 
CONSULTING THEIR LOCAL NEWS MEDIA AND THE INTERNET WEBSITE OF THE 
NATIONAL HURRICANE CENTER LOCATED AT HTTP://WWW.NHC.NOAA.GOV

THE OFFICIAL D+8 HEIGHT PROG CONSISTS OF 25 PERCENT OF TODAYS GFS
ENSEMBLE MEAN CENTERED ON DAY 8...25 PERCENT OF THE CANADIAN ENSEM-
BLE MEAN CENTERED ON DAY 8...25 PERCENT OF TODAYS ECMWF ENSEMBLE
CENTERED ON DAY 7...15 PERCENT OF TODAYS DAVA SOLUTION CENTERED ON
DAY 8...AND 10 PERCENT OF TODAYS OPERATIONAL 0Z GFS CENTERED ON 
DAY 8.

MODEL OF THE DAY: NO PREFERENCE

FORECAST CONFIDENCE FOR THE 6 TO 10 DAY PERIOD IS RATED AS ABOVE
AVERAGE TODAY...4 ON A SCALE FROM 1 TO 5.

THE 6 TO 10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN... NEURAL
NETWORK...AND ANALOG SPECIFICATIONS FROM THE OFFICIAL 500-HPA BLEND
...AS WELL AS ON THE LATEST 5-DAY MEAN OBSERVED TEMPERATURES.  THE
CDC REFORECAST TEMPERATURE TOOL WAS NOT AVAILABLE TODAY.  THE HEAVY
RAINS PREDICTED FROM TROPICAL STORM BONNIE AND HURRICANE CHARLEY IN
THE NEXT FEW DAYS ACROSS MUCH OF THE EASTERN SEABOARD WILL LIKELY 
HOLD TEMPERATURES DOWN A BIT OVER THAT REGION DURING THE 6-10 DAY 
RANGE.

THE 6 TO 10 DAY PRECIPITATION PROG IS BASED ON NEURAL NET AND ANALOG
SPECIFICATIONS FROM THE OFFICIAL 500-HPA PROG...CALIBRATED PRECIPI-
TATION PERCENTAGES FROM THE GFS ENSEMBLE MEMBERS...AND BIAS CORREC-
TED PRECIPITATION FROM THE 0Z GFS.  THE CDC REFORECAST TOOL FOR PRE-
CIPITATION WAS NOT AVAILABLE TODAY.  

         .         .         .         .         .         .         .
8 TO 14 DAY OUTLOOK FOR AUGUST 20 - 26 2004

FOR WEEK 2...LITTLE CHANGE IS ANTICIPATED IN THE MEAN FLOW PATTERN 
FROM DAYS 6-10.  WEAK TROUGHING REMAINS OFF THE U.S. WEST COAST...
AND A SIGNIFICANTLY STRONGER TROUGH PERSISTS OVER THE EAST-CENTRAL
STATES.  ANOMALOUS RIDGING IS INDICATED OVER MOST OF ALASKA...AND
ALSO OVER THE SOUTHERN CANADIAN MARITIMES REGION.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 50 PERCENT OF TODAYS
GFS ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF TODAYS DAVA
CENTERED ON DAY 11...20 PERCENT OF TODAYS 6Z GFS CENTERED ON DAY 11
...AND 10 PERCENT OF YESTERDAYS 12Z GFS CENTERED ON DAY 10.

FORECAST CONFIDENCE FOR THE 8 TO 14 DAY PERIOD IS ABOVE AVERAGE...4
ON A SCALE OF 1 TO 5.

THE 8 TO 14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN...NEURAL NET-
WORK...AND ANALOG SPECIFICATIONS FROM THE OFFICIAL 500-HPA BLEND.  A
NEW TOOL...THE WEEK 2 GFS ENSEMBLE MEAN 2-METER CALIBRATED TEMPERA-
TURE TOOL...WAS ALSO USED TO SOME EXTENT IN THE FORMULATION OF THE
SURFACE TEMPERATURE PROG.

THE 8 TO 14 DAY PRECIPITATION PROG IS BASED ON NEURAL NET AND ANALOG
SPECIFICATIONS FROM THE OFFICIAL 500-HPA PROG...CALIBRATED PRECIPI-
TATION PERCENTAGES FROM THE GFS ENSEMBLE MEMBERS...AND BIAS CORREC-
TED PRECIPITATION FROM THE 0Z GFS.

FORECASTER: A. ARTUSA
         .         .         .         .         .         .         .
NOTES: 

AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY.  OTHERWISE -
FORECASTS INCORPORATE FORECASTER INPUT.

THE NOTATION FOR THE CATEGORICAL FORECAST INDICATED ON THE MAPS IS
THE SAME AS THAT IN THE TABLES: A-ABOVE   N-NEAR NORMAL   B-BELOW

IN THE SOUTHWEST AND OTHER CLIMATOLOGICALLY DRY REGIONS - THERE WILL
BE A GREATER THAN 33.3% CHANCE OF NO PRECIPITATION AND OCCASIONALLY
EVEN A NORMAL (I.E. MEDIAN) VALUE OF ZERO - ESPECIALLY DURING THE DRY
SEASONS.  IN SUCH CASES A FORECAST OF NEAR NORMAL IS EFFECTIVELY A
FORECAST OF LITTLE OR NO PRECIPITATION.

THE NARRATIVE DESCRIPTION OF THE FORECAST PATTERNS FOR TEMPERATURE
AND PRECIPITATION FOR BOTH THE 6-10 OR 8-14 DAY PERIODS HAS BEEN
DISCONTINUED.  THE STATE TABLES FOR BOTH THE 6-10 AND 8-14 DAY
PERIODS ARE NOW CONTAINED IN THIS MESSAGE...AVAILABLE AS PMDMRD ON
AWIPS. 

EFFECTIVE THURSDAY MAY 17 2001...THE CLIMATE PREDICTION CENTER
HAS SWITCHED TO 1971-2000 BASE PERIOD MEANS FOR TEMPERATURE...
PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN THE CLIMATE
OUTLOOKS.  THE 1971-2000 BASE PERIOD MEANS HAVE REPLACED THE
1961-1990 BASE PERIOD MEANS.
 
THE NEXT MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED THURSDAY...
AUGUST 19.





NEW NOTE EFFECTIVE MAR 16 2004:
THE GLOSSARY FORMERLY FOUND AT THIS LOCATION WILL NO LONGER BE
TRANSMITTED AS PART OF THIS MESSAGE. IF YOU WISH TO SEE THE
DEFINITIONS OF TERMS USED IN THESE MESSAGES... PLEASE GO TO THE
CPC WEB PAGE AT (USE LOWER CASE) HTTP://WWW.CPC.NCEP.NOAA.GOV
AND FOLLOW THE APPROPRIATE LINKS.

ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES: 
19650730 - 19960723 - 19620726 - 19930801 - 19500810
 
ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19650729 - 19960723 - 19620726 - 19630814 - 19500723
 
6 to 10 day Outlook Table
OUTLOOK FOR AUG 18 - 22, 2004
 
STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN   
WASHINGTON  A    B     OREGON      A    B     NRN CALIF   A    B     
SRN CALIF   A    B     IDAHO       A    B     NEVADA      A    B     
W MONTANA   N    B     E MONTANA   N    B     WYOMING     B    A     
UTAH        N    N     ARIZONA     N    N     COLORADO    B    A     
NEW MEXICO  B    A     N DAKOTA    B    N     S DAKOTA    B    N     
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    B    A     
N TEXAS     B    N     S TEXAS     B    N     W TEXAS     B    A     
MINNESOTA   B    A     IOWA        B    A     MISSOURI    B    A     
ARKANSAS    B    A     LOUISIANA   B    N     WISCONSIN   B    A     
ILLINOIS    B    A     MISSISSIPPI B    N     MICHIGAN    B    N     
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A     
TENNESSEE   B    A     ALABAMA     B    N     NEW YORK    B    N     
VERMONT     N    N     NEW HAMP    N    N     MAINE       N    N     
MASS        N    A     CONN        N    A     RHODE IS    N    A     
PENN        B    A     NEW JERSEY  B    A     W VIRGINIA  B    A     
MARYLAND    B    A     DELAWARE    B    A     VIRGINIA    B    A     
N CAROLINA  B    N     S CAROLINA  B    N     GEORGIA     B    N     
FL PNHDL    B    N     FL PENIN    N    A     AK N SLOPE  A    B     
AK ALEUTIAN A    A     AK WESTERN  A    B     AK INT BSN  A    B     
AK S INT    A    B     AK SO COAST A    B     AK PNHDL    A    B     
 
 
8 to 14 day Outlook Table
OUTLOOK FOR AUG 20 - 26, 2004
 
STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN   
WASHINGTON  A    A     OREGON      A    B     NRN CALIF   A    B     
SRN CALIF   A    N     IDAHO       A    B     NEVADA      A    B     
W MONTANA   A    N     E MONTANA   B    A     WYOMING     A    A     
UTAH        N    N     ARIZONA     N    A     COLORADO    B    A     
NEW MEXICO  N    A     N DAKOTA    B    N     S DAKOTA    B    N     
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    B    A     
N TEXAS     B    N     S TEXAS     B    N     W TEXAS     B    A     
MINNESOTA   B    B     IOWA        B    A     MISSOURI    B    A     
ARKANSAS    B    A     LOUISIANA   B    B     WISCONSIN   B    B     
ILLINOIS    B    A     MISSISSIPPI B    A     MICHIGAN    B    B     
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A     
TENNESSEE   B    A     ALABAMA     B    N     NEW YORK    B    N     
VERMONT     N    N     NEW HAMP    N    N     MAINE       A    N     
MASS        N    N     CONN        N    N     RHODE IS    N    N     
PENN        B    N     NEW JERSEY  B    N     W VIRGINIA  B    A     
MARYLAND    B    A     DELAWARE    B    N     VIRGINIA    B    A     
N CAROLINA  B    A     S CAROLINA  B    N     GEORGIA     B    N     
FL PNHDL    B    N     FL PENIN    N    N     AK N SLOPE  A    B     
AK ALEUTIAN A    A     AK WESTERN  A    B     AK INT BSN  A    B     
AK S INT    A    B     AK SO COAST A    B     AK PNHDL    A    N     
 
                           LEGEND
TEMPS WITH RESPECT TO NORMAL     PCPN WITH RESPECT TO MEDIAN
A - ABOVE   N  - NEAR NORMAL     A - ABOVE   N - NEAR MEDIAN
B - BELOW                        B - BELOW
 
THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.
 
FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.
 
$$