807  
FXUS06 KWBC 281903  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT TUE MAY 28 2024  
 
6-10 DAY OUTLOOK FOR JUN 03 - 07 2024  
 
TODAY'S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON A MODERATELY AMPLIFIED 500-HPA  
CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS DURING THE  
6-10 DAY PERIOD. THE MANUAL 500-HPA HEIGHT BLEND IS BASED ON THE ENSEMBLE MEANS  
FROM THE GEFS, ECMWF, AND CANADIAN MODELS DUE TO RECENT MODEL SKILL. THE  
RESULTANT MANUAL BLEND FEATURES STRONG TROUGHING AND NEGATIVE 500-HPA HEIGHT  
ANOMALIES OVER ALASKA AND THE GULF OF ALASKA. RIDGING AND POSITIVE HEIGHT  
ANOMALIES ARE FORECAST OVER THE WESTERN AND CENTRAL CONTIGUOUS U.S. (CONUS),  
WHILE ANOTHER TROUGH IS DEPICTED OVER THE SOUTHEAST AND WESTERN ATLANTIC. NEAR-  
TO SLIGHTLY ABOVE-NORMAL 500-HPA HEIGHTS ARE FORECAST OVER THE HAWAIIAN ISLANDS.  
 
ENHANCED CHANCES FOR ABOVE-NORMAL TEMPERATURES ARE PREDICTED OVER MOST OF THE  
CONUS DUE TO THE ANTICIPATED MID-LEVEL RIDGING, GENERALLY ABOVE-NORMAL 500-HPA  
HEIGHT ANOMALIES, AND INCREASED SOUTHWESTERLY SURFACE FLOW, SUPPORTED BY MOST  
OF THE DYNAMICAL TEMPERATURE FORECAST TOOLS. PROBABILITIES FAVORING ABOVE  
NORMAL TEMPERATURES EXCEED 80% FOR PARTS OF THE CENTRAL GREAT BASIN.  
BELOW-NORMAL TEMPERATURE PROBABILITIES ARE INCREASED OVER ALASKA, INCLUDING THE  
ALEUTIANS AND SOUTHEAST ALASKA, CLOSER TO THE MID-LEVEL TROUGH AND SURFACE  
STORMINESS. IN HAWAII, ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE SLIGHTLY  
FAVORED UNDERNEATH NEAR- TO WEAK POSITIVE HEIGHT ANOMALIES.  
 
ANOMALOUS MID-LEVEL RIDGING FAVORS BELOW-NORMAL PRECIPITATION OVER PARTS OF THE  
NORTHERN AND CENTRAL GREAT BASIN EXTENDING EASTWARD TO PORTIONS OF THE WESTERN  
UPPER MISSISSIPPI VALLEY. ABOVE-NORMAL PRECIPITATION IS LIKELY OVER THE PACIFIC  
NORTHWEST AND PARTS OF NORTHERN CALIFORNIA IN ASSOCIATION WITH A TROUGH  
PREDICTED OVER THE GULF OF ALASKA. ABOVE-NORMAL PRECIPITATION PROBABILITIES ARE  
ALSO INCREASED OVER MUCH OF THE EASTERN AND THE SOUTH-CENTRAL CONUS DUE TO  
SOUTHERLY RETURN FLOW ASSOCIATED WITH MEAN SURFACE HIGH PRESSURE OVER THE  
SOUTHEAST AND THE MID-LEVEL TROUGH EXPECTED TO LINGER IN THE REGION THROUGH  
MUCH OF THE PERIOD, AND SUPPORTED BY MOST OF THE DYNAMICAL PRECIPITATION  
FORECAST TOOLS. IN ALASKA, ABOVE-NORMAL PRECIPITATION CHANCES ARE ELEVATED OVER  
MUCH OF ALASKA DUE TO THE TREND TOWARD INCREASED TROUGHING TO THE SOUTH AND  
SOUTHWEST OF THE STATE LATER IN THE PERIOD, CONSISTENT WITH MOST TEMPERATURE  
GUIDANCE. IN HAWAII, BELOW-NORMAL PRECIPITATION PROBABILITIES ARE SLIGHTLY  
ELEVATED ACROSS HAWAII ISLANDS, CONSISTENT WITH THE CONSOLIDATION PRECIPITATION  
FORECAST TOOL.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S GFS  
SUPERENSEMBLE 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 JUN 05 - 11 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.THE GEFS AND ECMWF ARE IN GOOD AGREEMENT  
REGARDING A RIDGE WITH ABOVE-NORMAL 500-HPA HEIGHTS OVER THE WESTERN AND  
CENTRAL CONUS DURING THE WEEK-2 PERIOD. WEAK ANOMALOUS TROUGHING IS FORECAST  
OVER THE EASTERN CONUS. STRONG TROUGHING AND NEGATIVE 500-HPA HEIGHT ANOMALIES  
ARE PERSISTENT OVER MUCH OF ALASKA AND THE GULF OF ALASKA. NEAR- TO SLIGHTLY  
ABOVE-NORMAL 500-HPA HEIGHTS ARE STILL PREDICTED OVER THE HAWAIIAN ISLANDS.  
 
THE SUBTROPICAL RIDGE AND BROADLY ABOVE-NORMAL 500-HPA HEIGHTS AS WELL AS  
INCREASED SOUTHWESTERLY SURFACE FLOW OVER THE SOUTH-CENTRAL CONUS FAVOR  
ELEVATED PROBABILITIES FOR NEAR- TO ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE  
CONUS, WITH THE HIGHEST PROBABILITIES PERSISTING ACROSS PORTIONS OF NORTHERN  
AND CENTRAL GREAT BASIN. ONE EXCEPTION IS OVER PARTS OF THE OHIO AND TENNESSEE  
VALLEYS AS WELL AS PORTIONS OF THE SOUTHERN UPPER GREAT LAKES FAVORING SLIGHTLY  
BELOW-NORMAL TEMPERATURES DUE TO LINGERING INFLUENCE FROM A TROUGH AND NEGATIVE  
500-HPA ANOMALIES PREDICTED OVER THE REGION. IN ALASKA, BELOW-NORMAL  
TEMPERATURE CHANCES ARE INCREASED OVER SOUTHERN PORTIONS OF THE STATE, WHILE  
ABOVE-NORMAL TEMPERATURES ARE LIKELY OVER NORTHERN PARTS OF THE STATE. IN  
HAWAII, ABOVE-NORMAL TEMPERATURES ARE SLIGHTLY FAVORED OVER THE STATE,  
CONSISTENT WITH THE CONSOLIDATION TEMPERATURE FORECAST TOOL.  
 
INCREASED PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION ARE FAVORED ACROSS MUCH  
OF THE SOUTHWESTERN AND NORTHEASTERN CONUS, SUPPORTED BY MOST OF THE  
PRECIPITATION FORECAST TOOLS. THERE IS A TILT TOWARD ELEVATED BELOW-NORMAL  
PRECIPITATION PROBABILITIES ACROSS THE PACIFIC NORTHWEST EXTENDING EASTWARD TO  
THE WESTERN UPPER GREAT LAKES, UNDER A RIDGE AND POSITIVE 500-HPA ANOMALIES  
PREDICTED OVER THE REGION. THERE ARE ENHANCED CHANCES FOR ABOVE-NORMAL  
PRECIPITATION OVER MUCH OF ALASKA, UNDER A MOIST PACIFIC AIR MASS AND SOME  
POTENTIAL INFLUENCE FROM THE STRONG TROUGHING CENTERED NEAR SOUTHERN ALASKA.  
SLIGHTLY DRIER THAN NORMAL WEATHER IS LIKELY ACROSS THE HAWAII ISLANDS,  
CONSISTENT WITH THE CONSOLIDATION PRECIPITATION FORECAST TOOL.  
 
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: ABOVE AVERAGE, 4 OUT OF 5, WITH  
GOOD RUN-TO-RUN CONTINUITY AMONG FORECAST MODELS, OFFSET BY DIFFERENCES BETWEEN  
MODELS REGARDING STRENGTH AND POSITION OF VARIOUS SYNOPTIC FEATURES.  
 
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  
JUNE 20.  
 
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:  
19660514 - 19660519 - 20040529 - 19620601 - 19890519  
 
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:  
19660515 - 20040529 - 19620530 - 19660520 - 19890520  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR JUN 03 - 07 2024  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A N  
SRN CALIF A N IDAHO A B NEVADA A B  
W MONTANA A B E MONTANA A B WYOMING A B  
UTAH A B ARIZONA A N COLORADO A B  
NEW MEXICO A A N DAKOTA A B S DAKOTA A B  
NEBRASKA A B KANSAS A N OKLAHOMA A A  
N TEXAS A A S TEXAS A A W TEXAS A A  
MINNESOTA A N IOWA A B MISSOURI A A  
ARKANSAS A A LOUISIANA A A WISCONSIN A N  
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A  
INDIANA A A OHIO A A KENTUCKY A A  
TENNESSEE A A ALABAMA A A NEW YORK A A  
VERMONT A A NEW HAMP A A MAINE A A  
MASS A 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 N FL PENIN A N AK N SLOPE B A  
AK ALEUTIAN B N AK WESTERN B A AK INT BSN B A  
AK S INT B A AK SO COAST B A AK PNHDL B A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR JUN 05 - 11 2024  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A B OREGON A B NRN CALIF A N  
SRN CALIF A A IDAHO A B NEVADA A N  
W MONTANA A B E MONTANA A B WYOMING A B  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA A B S DAKOTA A B  
NEBRASKA A B KANSAS A B OKLAHOMA A N  
N TEXAS A N S TEXAS A N W TEXAS A A  
MINNESOTA A B IOWA A B MISSOURI N B  
ARKANSAS A N LOUISIANA A N WISCONSIN A B  
ILLINOIS N B MISSISSIPPI A N MICHIGAN N N  
INDIANA N N OHIO N N KENTUCKY N N  
TENNESSEE N N ALABAMA A N NEW YORK N A  
VERMONT N A NEW HAMP N A MAINE A A  
MASS N A CONN N A RHODE IS N A  
PENN N A NEW JERSEY N A W VIRGINIA N N  
MARYLAND N A DELAWARE N A VIRGINIA N N  
N CAROLINA A N S CAROLINA A N GEORGIA A N  
FL PNHDL A N FL PENIN A N AK N SLOPE A N  
AK ALEUTIAN B N AK WESTERN B A AK INT BSN B A  
AK S INT B A AK SO COAST B A AK PNHDL B A  
 
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