035  
FXUS06 KWBC 301902  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT TUE JULY 30 2024  
 
6-10 DAY OUTLOOK FOR AUG 05 - 09 2024  
 
TODAY'S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 500-HPA  
CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS DURING THE  
6-10 DAY PERIOD. THE MANUAL 500-HPA HEIGHT BLEND IS BASED PRIMARILY ON THE  
ENSEMBLE MEANS FROM THE GEFS, ECMWF AND CANADIAN MODELS DUE TO RECENT MODEL  
SKILL. THE RESULTANT MANUAL BLEND FEATURES A TROUGH CENTERED IN THE CHUKCHI SEA  
EXTENDING SOUTHWARD INTO THE ALEUTIANS AND THE NORTH PACIFIC. ANOTHER TROUGH  
WITH NEGATIVE 500-HPA HEIGHT ANOMALIES IS FORECAST OVER EASTERN CANADA AND THE  
NORTHEASTERN CONUS. A MID-LEVEL RIDGE AND ASSOCIATED POSITIVE 500-HPA HEIGHT  
ANOMALIES ARE PREDICTED OVER MAINLAND ALASKA AND THE WESTERN CONTIGUOUS U.S.  
(CONUS). POSITIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST OVER MOST OF THE CONUS.  
WEAK POSITIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED OVER HAWAII.  
 
ENHANCED CHANCES FOR ABOVE-NORMAL TEMPERATURES ARE LIKELY ACROSS MOST OF THE  
CONUS (EXCEPT FOR PARTS OF THE NORTHERN PLAINS, THE UPPER MISSISSIPPI VALLEY,  
THE UPPER GREAT LAKES, AND MAINE, WHERE BELOW NORMAL TEMPERATURES ARE PREDICTED  
DUE TO A PREDICTED TROUGH AND ANOMALOUS NORTHERLY FLOW OVER THE REGION) AS  
POSITIVE 500-HPA HEIGHT ANOMALIES ARE PREDICTED OVER MOST OF THE CONUS DURING  
MUCH OF THE PERIOD, SUPPORTED BY THE DYNAMICAL TEMPERATURE FORECAST TOOLS.  
PROBABILITIES FAVORING ABOVE NORMAL TEMPERATURES EXCEED 80% FOR PORTIONS OF  
THE NORTHERN AND CENTRAL GREAT BASIN. ABOVE-NORMAL TEMPERATURE CHANCES ARE  
INCREASED OVER MOST OF MAINLAND ALASKA AND SOUTHEAST ALASKA, DUE TO A PREDICTED  
RIDGE AND ABOVE-NORMAL 500-HPA HEIGHTS, WHILE BELOW-NORMAL TEMPERATURES ARE  
FAVORED OVER THE ALEUTIANS, UNDER A TROUGH AND NEGATIVE 500-HPA HEIGHT  
ANOMALIES, CONSISTENT WITH SHORT-TERM BIAS-CORRECTED TEMPERATURE FORECASTS OF  
THE GEFS AND ECMWF ENSEMBLE MODELS. ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE  
FORECAST FOR HAWAII, UNDERNEATH WEAK POSITIVE 500-HPA HEIGHT ANOMALIES.  
 
BELOW-NORMAL PRECIPITATION IS SLIGHTLY FAVORED OVER PARTS OF THE PACIFIC  
NORTHWEST, WHILE NEAR-TO-ABOVE-NORMAL PRECIPITATION IS FAVORED OVER MOST OF THE  
REMAINDER OF THE CONUS, CONSISTENT WITH REFORECAST-CALIBRATED PRECIPITATION  
FORECASTS FROM THE GEFS AND ECMWF ENSEMBLES WITH ENHANCED MOISTURE FLOW FROM  
THE TROPICS. ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS WESTERN MAINLAND  
ALASKA AND THE ALEUTIANS, UNDER ENHANCED ONSHORE FLOW OR CYCLONIC FLOW AHEAD OF  
A TROUGH. BELOW-NORMAL PRECIPITATION IS FAVORED FOR EASTERN MAINLAND ALASKA AND  
SOUTHEAST ALASKA, DUE TO A PREDICTED RIDGE AND ABOVE-NORMAL 500-HPA HEIGHTS.  
BELOW-NORMAL PRECIPITATION IS FAVORED FOR HAWAII, AS PREDICTED BY THE AUTO  
PRECIPITATION FORECAST TOOL AND CONSISTENT WITH THE CONSOLIDATION.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 6Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 8, AND 30% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY  
8  
 
 
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO  
GOOD AGREEMENT AMONG MODEL SOLUTIONS AND FORECAST TEMPERATURE AND PRECIPITATION  
TOOLS.  
 
8-14 DAY OUTLOOK FOR AUG 07 - 13 2024  
 
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD PREDICT A FAIRLY CONSISTENT  
500-HPA CIRCULATION PATTERN RELATIVE TO THE 6-10 DAY PERIOD ACROSS NORTH  
AMERICA AND THE SURROUNDING REGIONS. DURING WEEK-2, ENSEMBLE MEANS FROM THE  
GEFS, ECMWF AND CANADIAN MODELS PREDICT A STRONG RIDGE AND POSITIVE 500-HPA  
HEIGHT ANOMALIES OVER MAINLAND ALASKA AND SOUTHEAST ALASKA, WHILE A TROUGH  
CONTINUES TO BE PREDICTED TO THE WEST OF ALASKA. A MID-LEVEL RIDGE IS  
PREDICTED ACROSS THE WESTERN AND CENTRAL CONUS WITH TROUGHING FORECAST OVER  
EASTERN CANADA AND THE NORTHEASTERN CONUS. WEAK POSITIVE 500-HPA HEIGHT  
ANOMALIES ARE PREDICTED OVER HAWAII.  
 
ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE PREDICTED ACROSS MOST OF THE CONUS,  
UNDER A MID-LEVEL RIDGE AND ABOVE NORMAL 500-HPA HEIGHTS, CONSISTENT WITH MOST  
DYNAMICAL MODEL TEMPERATURE TOOLS. BELOW-NORMAL TEMPERATURES ARE FAVORED FOR  
PARTS OF THE NORTHERN ROCKIES, THE NORTHERN PLAINS, THE UPPER AND MIDDLE  
MISSISSIPPI VALLEY, THE GREAT LAKES, AND THE NORTHEAST, UNDER NEAR-TO-BELOW  
NORMAL 500-HPA HEIGHTS, CONSISTENT WITH THE AUTOMATED TEMPERATURE FORECAST  
BLEND OF TOOLS. BELOW-NORMAL TEMPERATURES ARE FAVORED FOR PORTIONS OF  
SOUTHWESTERN ALASKA AND THE ALEUTIANS, UNDER PREDICTED NEGATIVE 500-HPA HEIGHT  
ANOMALIES OR ANOMALOUS NORTHWESTERLY FLOW IN THE MANUAL BLEND AND MOST  
DYNAMICAL MODEL FORECASTS. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MOST OF  
MAINLAND ALASKA AND SOUTHEAST ALASKA, DUE TO THE ABOVE-NORMAL 500-HPA HEIGHTS,  
CONSISTENT WITH THE TEMPERATURE CONSOLIDATION. ABOVE-NORMAL TEMPERATURES ARE  
FAVORED FOR HAWAII, UNDER WEAK POSITIVE 500-HPA HEIGHT ANOMALIES.  
 
NEAR-TO-ABOVE-NORMAL PRECIPITATION IS FAVORED OVER THE ENTIRE CONUS IN WEEK-2,  
CONSISTENT WITH MOST PRECIPITATION TOOLS AND THE CONSOLIDATION. ABOVE-NORMAL  
PRECIPITATION CONTINUES TO BE FAVORED FOR WESTERN AND CENTRAL MAINLAND ALASKA  
AS WELL AS THE ALEUTIAN ISLANDS, UNDER ENHANCED ONSHORE AND CYCLONIC FLOW,  
WHILE NEAR-TO-BELOW-NORMAL PRECIPITATION IS FAVORED FOR SOUTHEASTERN MAINLAND  
ALASKA AND SOUTHEAST ALASKA, UNDER RISING POSITIVE 500-HPA HEIGHT ANOMALIES.  
BASED ON THE AUTOBLEND, BELOW-NORMAL PRECIPITATION IS SLIGHTLY FAVORED ACROSS  
HAWAII.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S GFS  
SUPERENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 11, AND 30% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON  
DAY 11  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: ABOUT-AVERAGE, 3 OUT OF 5, DUE TO  
GOOD GENERAL AGREEMENT AMONG THE DYNAMICAL MODEL HEIGHT FORECASTS, OFFSET BY  
DIFFERENCES IN TEMPERATURE AND PRECIPITATION TOOLS FOR SOME AREAS.  
 
FORECASTER: LUKE H  
 
NOTES:  
 
AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OCCASIONALLY MANUAL  
INTERVENTION IS NECESSARY TO ADDRESS QUALITY CONTROL AND CONSISTENCY ISSUES. IN  
THESE CASES, FORECASTS ARE MANUALLY DRAWN BUT A FULL DISCUSSION IS NOT ISSUED.  
 
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  
 
THE TEMPERATURE MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WARMER (ORANGE,  
"A"), COLDER (BLUE, "B"), OR CLOSE TO (UNSHADED, "N"). HISTORICAL AVERAGE  
VALUES FOR THE CALENDAR PERIOD OF THE FORECAST (DASHES, "F"). LABELS ON THE  
SHADED LINES GIVE THE PROBABILITY (> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  
PROBABILITY OF N IS ALWAYS < 40%.  
 
THE PRECIPITATION MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WETTER (GREEN,  
"A"), DRIER (TAN, "B"), OR CLOSE TO (UNSHADED, "N"). HISTORICAL MEDIAN VALUES  
FOR THE CALENDAR PERIOD OF THE FORECAST (DASHES, "INCHES"). LABELS ON THE  
SHADED LINES GIVE THE PROBABILITY (> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  
PROBABILITY OF N IS ALWAYS < 40%.  
 
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 CLIMATE PREDICTION CENTER USES 1991-2020 BASE PERIOD MEANS AS REFERENCE IN  
THE CLIMATE OUTLOOKS.  
 
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON  
AUGUST 15.  
 
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:  
19630715 - 19960803 - 19880805 - 19990724 - 19880810  
 
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:  
19510709 - 19520709 - 19530709 - 19540709 - 19550709  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR AUG 05 - 09 2024  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A N NRN CALIF A A  
SRN CALIF A A IDAHO A A NEVADA A A  
W MONTANA A A E MONTANA N A WYOMING A A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA B A S DAKOTA A A  
NEBRASKA A A KANSAS A A OKLAHOMA A N  
N TEXAS A N S TEXAS A A W TEXAS A N  
MINNESOTA B A IOWA A A MISSOURI A N  
ARKANSAS A N LOUISIANA A N WISCONSIN N A  
ILLINOIS A A MISSISSIPPI A N MICHIGAN A A  
INDIANA A A OHIO A A KENTUCKY A N  
TENNESSEE A N ALABAMA A N NEW YORK A A  
VERMONT N A NEW HAMP A A MAINE B A  
MASS A A CONN A A RHODE IS A A  
PENN A A NEW JERSEY A A W VIRGINIA A N  
MARYLAND A A DELAWARE A A VIRGINIA A A  
N CAROLINA A A S CAROLINA A A GEORGIA A A  
FL PNHDL A A FL PENIN A A AK N SLOPE A A  
AK ALEUTIAN B A AK WESTERN A A AK INT BSN A B  
AK S INT A A AK SO COAST A A AK PNHDL A B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR AUG 07 - 13 2024  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF A A IDAHO A A NEVADA A A  
W MONTANA B A E MONTANA B A WYOMING B A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA B A S DAKOTA B A  
NEBRASKA B A KANSAS A A OKLAHOMA A A  
N TEXAS A N S TEXAS A N W TEXAS A A  
MINNESOTA B A IOWA B A MISSOURI A A  
ARKANSAS A A LOUISIANA A N WISCONSIN B A  
ILLINOIS A A MISSISSIPPI A N MICHIGAN B A  
INDIANA A A OHIO A A KENTUCKY A A  
TENNESSEE A A ALABAMA A A NEW YORK A A  
VERMONT B A NEW HAMP N A MAINE B A  
MASS N A CONN A A RHODE IS A A  
PENN A A NEW JERSEY A A W VIRGINIA A A  
MARYLAND A A DELAWARE A A VIRGINIA A A  
N CAROLINA A A S CAROLINA A A GEORGIA A A  
FL PNHDL A A FL PENIN A A AK N SLOPE A A  
AK ALEUTIAN B A AK WESTERN A A AK INT BSN A A  
AK S INT A A AK SO COAST A A AK PNHDL A B  
 
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.  
 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab HPC Page
Main Text Page