719  
FXUS06 KWBC 031904  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT MON JULY 03 2023  
 
6-10 DAY OUTLOOK FOR JUL 09 - 13 2023  
 
TODAY'S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 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 PRIMARILY ON THE  
ENSEMBLE MEANS FROM THE GFS, ECMWF, AND CANADIAN MODEL ENSEMBLES DUE TO RECENT  
MODEL SKILL. THE RESULTANT MANUAL BLEND FEATURES TROUGHING ACROSS THE EASTERN  
BERING SEA WITH RIDGING DOWNSTREAM OVER THE NORTHEAST PACIFIC, INCLUDING  
EASTERN ALASKA. A WEAK TROUGH IS PREDICTED ALONG THE WEST COAST OF THE CONUS.  
ACROSS THE REMAINDER OF THE CONUS, THE DOMINANT FEATURE IS FORECAST TO BE A  
SHORTWAVE TROUGH MOVING FROM THE ROCKIES TOWARD THE EAST COAST. A TREND TOWARD  
HIGHER MID-LEVEL HEIGHTS AND MORE RIDGING IS POSSIBLE ACROSS THE SOUTHWEST BY  
THE END OF THE PERIOD AS THE SHORTWAVE TROUGHING MOVES FURTHER DOWNSTREAM. FOR  
ALASKA, BELOW-NORMAL HEIGHTS ARE FAVORED ACROSS THE EXTREME WESTERN MAINLAND,  
WITH ABOVE-NORMAL HEIGHTS FORECAST OVER THE REMAINDER OF ALASKA, UNDERNEATH  
ANOMALOUS MID-LEVEL RIDGING.  
 
SHORTWAVE TROUGHING AND AN ASSOCIATED FRONTAL SYSTEM IS LIKELY TO RESULT IN  
ENHANCED PROBABILITIES OF BELOW-NORMAL TEMPERATURES BEING ELEVATED ACROSS MUCH  
OF THE NORTHERN AND CENTRAL ROCKIES, EXTENDING EASTWARD THROUGH THE MIDWEST,  
THE OHIO VALLEY, AND THE GREAT LAKES REGIONS. ABOVE-NORMAL TEMPERATURE  
PROBABILITIES REMAIN INCREASED ACROSS PORTIONS OF THE SOUTHEAST AND NORTHEAST.  
CHANCES FOR ABOVE-NORMAL TEMPERATURES ARE ALSO INCREASED ACROSS THE SOUTHERN  
PLAINS EXTENDING TO THE WESTERN CONUS DUE TO BUILDING SUBTROPICAL RIDGING OVER  
THE SOUTHWEST/SOUTHERN PLAINS AND PREDICTED RIDGING OVER THE NORTHEAST PACIFIC.  
INCREASED TROUGHING OVER THE BERING SEA FAVORS BELOW-NORMAL TEMPERATURES  
ACROSS SOUTHWESTERN PORTIONS OF ALASKA, CONSISTENT WITH THE GEFS AND ECMWF  
REFORECAST CONSOLIDATION TOOL. NEAR- TO ABOVE-NORMAL TEMPERATURES ARE FAVORED  
ACROSS PARTS OF EASTERN AND NORTHERN ALASKA GIVEN CLOSER PROXIMITY TO THE RIDGE  
AND SUPPORTED BY THE ECMWF GUIDANCE.  
 
PREDICTED SHORTWAVE TROUGHING AND AN ASSOCIATED FRONTAL DISTURBANCE MOVING  
ACROSS THE EASTERN TWO-THIRDS OF THE CONUS LEAD TO ENHANCED PRECIPITATION  
CHANCES OVER MANY AREAS FROM THE NORTHERN AND CENTRAL ROCKIES THROUGH THE GREAT  
PLAINS, MISSISSIPPI, TENNESSEE, AND OHIO VALLEYS,GREAT LAKES REGION,  
MID-ATLANTIC, AND NORTHEAST. BELOW-NORMAL PRECIPITATION PROBABILITIES ARE  
INCREASED ACROSS PARTS OF THE SOUTHERN PLAINS, NEVADA, AND THE FOUR CORNERS  
REGION DUE TO SUBTROPICAL RIDGING AND A SLOW START TO THE MONSOON. RIDGING  
ACROSS THE NORTHEAST PACIFIC FAVORS INCREASED NEAR- TO BELOW-NORMAL  
PRECIPITATION PROBABILITIES ACROSS SOUTHEASTERN ALASKA. TROUGHING OVER THE  
BERING SEA AND ASSOCIATED ENHANCED SOUTHERLY FLOW FAVORED ABOVE-NORMAL  
PRECIPITATION CHANCES FOR THE REMAINDER OF MAINLAND ALASKA AND THE ALEUTIANS.  
 
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 NORMAL, 4 OUT OF 5, DUE TO  
PERSISTENT SYNOPTIC PATTERN AND GOOD AGREEMENT AMONG FORECAST MODELS, OFFSET BY  
WEAKENING OF HIGH AMPLITUDE PATTERN LATE IN FORECAST PERIOD.  
 
8-14 DAY OUTLOOK FOR JUL 11 - 17 2023  
 
THE 500-HPA HEIGHT PATTERN DURING WEEK-2 IS PREDICTED TO BE SIMILAR TO THE 6-10  
DAY PERIOD. RIDGING AND ABOVE NORMAL 500-HPA HEIGHTS REMAINS FAVORED ACROSS  
THE NORTHEAST PACIFIC AND NORTHWEST ATLANTIC. THE GENERAL PATTERN IS LIKELY TO  
BE INCREASING SUBTROPICAL RIDGING ACROSS THE SOUTHERN TIER, WITH WEAK TROUGHING  
AND NEGATIVE 500-HPA ANOMALIES REMAINING ACROSS THE NORTHEASTERN CONUS.  
TROUGHING IS FORECAST TO WEAKEN ACROSS THE BERING SEA, ALONG WITH A  
RETROGRESSION OF THE RIDGING ACROSS THE NORTHEAST PACIFIC, LEADING TO HIGHER  
HEIGHTS OVER ALASKA COMPARED TO THE 6-10 DAY PERIOD.  
 
DURING WEEK-2, INCREASED PROBABILITIES FOR BELOW-NORMAL TEMPERATURES ARE  
FORECAST OVER THE NORTHERN PLAINS, THE UPPER AND MIDDLE MISSISSIPPI VALLEY, AND  
SPREADING EASTWARD INTO PARTS OF THE MID-ATLANTIC AND NORTHEAST. A TILT TOWARD  
INCREASED PROBABILITIES FOR NEAR-NORMAL TEMPERATURES IS FORECAST ACROSS NEW  
ENGLAND WHERE SLIGHTLY ABOVE-NORMAL MID-LEVEL HEIGHTS ARE PREDICTED DUE TO  
RIDGING OVER THE NORTHWEST ATLANTIC. INCREASING SUBTROPICAL RIDGING FAVORS  
ELEVATED PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ALONG THE SOUTHERN TIER,  
ESPECIALLY ACROSS PORTIONS OF SOUTHERN TEXAS WHERE RENEWED EXCESSIVE HEAT  
CONCERNS ARE PREDICTED DURING THE PERIOD. INCREASED PROBABILITIES OF NEAR- TO  
ABOVE-NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR THE WESTERN CONUS DUE TO  
RIDGING OVER THE NORTHEAST PACIFIC. ENHANCED ONSHORE FLOW FAVORS A PERSISTENCE  
OF ELEVATED BELOW-NORMAL TEMPERATURE PROBABILITIES ACROSS MUCH OF WESTERN  
ALASKA, WITH A STRONGER INFLUENCE FROM RIDGING AND HIGHER MID-LEVEL HEIGHTS  
FAVORING INCREASED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ACROSS EASTERN  
PORTIONS OF THE STATE.  
 
AS DISCUSSED IN THE 6-10 DAY OUTLOOK, SHORTWAVE TROUGHING IS FORECAST TO LEAD  
TO A FRONTAL SYSTEM MOVING ACROSS THE EASTERN CONUS EARLY IN THE WEEK-2 PERIOD.  
AS A RESULT, ABOVE-NORMAL PRECIPITATION IS FORECAST OVER NORTHERN WASHINGTON,  
NORTHERN IDAHO, PARTS OF THE NORTHERN AND CENTRAL PLAINS EXTENDING EASTWARD TO  
PORTIONS OF THE MID-ATLANTIC AND NORTHEAST. NEAR-TO-BELOW NORMAL PRECIPITATION  
CONTINUES TO BE SLIGHTLY FAVORED FOR PARTS OF SOUTHWESTERN AND SOUTHEAST  
ALASKA, UNDERNEATH THE RIDGE OVER THE NORTHEAST PACIFIC. ENHANCED  
PROBABILITIES FOR BELOW-NORMAL PRECIPITATION ARE ALSO FAVORED FOR PARTS OF  
IDAHO, NEVADA, UTAH, ARIZONA, THE SOUTHERN HIGH PLAINS, AND THE LOWER  
MISSISSIPPI VALLEY DUE TO A LATE START TO THE MONSOON AND PREDICTED SUBTROPICAL  
RIDGE OVER THE REGION. NEAR- TO ABOVE-NORMAL PRECIPITATION PROBABILITIES ARE  
INCREASED ACROSS MOST OF NORTHERN AND CENTRAL MAINLAND ALASKA, DUE TO WEST TO  
SOUTHWESTERLY SURFACE FLOW AND SUPPORTED BY MOST DYNAMICAL MODEL PRECIPITATION  
TOOLS.  
 
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: 3 OUT OF 5, DUE TO FAIR AGREEMENT  
AMONG MODEL ENSEMBLES ON THE PERSISTENT SYNOPTIC PATTERN, OFFSET BY WEAKER  
ANOMALIES REDUCING FORECAST CONFIDENCE.  
 
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  
JULY 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:  
19520707 - 19940716 - 19870711 - 19890621 - 19530717  
 
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:  
19520708 - 19890620 - 19870710 - 19870625 - 19940715  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR JUL 09 - 13 2023  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A N NRN CALIF A N  
SRN CALIF A N IDAHO A A NEVADA A B  
W MONTANA A A E MONTANA B A WYOMING B A  
UTAH A B ARIZONA A B COLORADO A N  
NEW MEXICO A B N DAKOTA B A S DAKOTA B A  
NEBRASKA B A KANSAS A A OKLAHOMA A N  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA B A IOWA B A MISSOURI B A  
ARKANSAS A A LOUISIANA A B WISCONSIN B A  
ILLINOIS B A MISSISSIPPI A N MICHIGAN B A  
INDIANA B A OHIO B A KENTUCKY B A  
TENNESSEE A A ALABAMA A A NEW YORK N A  
VERMONT N A NEW HAMP N A MAINE N A  
MASS N A CONN N A RHODE IS N A  
PENN B A NEW JERSEY N A W VIRGINIA B A  
MARYLAND N A DELAWARE N A VIRGINIA N A  
N CAROLINA A A S CAROLINA A A GEORGIA A A  
FL PNHDL A N FL PENIN A N AK N SLOPE N A  
AK ALEUTIAN N A AK WESTERN B A AK INT BSN N A  
AK S INT B A AK SO COAST B A AK PNHDL A B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR JUL 11 - 17 2023  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A N OREGON A N NRN CALIF A N  
SRN CALIF A N IDAHO A B NEVADA A B  
W MONTANA A N E MONTANA N N WYOMING N N  
UTAH A B ARIZONA A N COLORADO A N  
NEW MEXICO A N N DAKOTA B N S DAKOTA B N  
NEBRASKA N N KANSAS A N OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA B N IOWA B N MISSOURI A N  
ARKANSAS A N LOUISIANA A B WISCONSIN B N  
ILLINOIS B N MISSISSIPPI A B MICHIGAN B N  
INDIANA B N OHIO B N KENTUCKY B N  
TENNESSEE A N ALABAMA A N NEW YORK B N  
VERMONT N N NEW HAMP N N MAINE N N  
MASS N N CONN B N RHODE IS N N  
PENN B N NEW JERSEY B N W VIRGINIA B N  
MARYLAND B N DELAWARE B N VIRGINIA B N  
N CAROLINA A N S CAROLINA A N GEORGIA A N  
FL PNHDL A N FL PENIN A N AK N SLOPE N A  
AK ALEUTIAN N N AK WESTERN B A AK INT BSN A A  
AK S INT B N AK SO COAST B N 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.  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page