685  
FXUS06 KWBC 191951  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT TUE AUGUST 19 2025  
 
6-10 DAY OUTLOOK FOR AUG 25 - 29 2025  
 
TODAY'S ENSEMBLE MEAN SOLUTIONS GENERALLY DEPICT A HIGH AMPLITUDE PATTERN  
ACROSS MUCH OF NORTH AMERICA AND SURROUNDING AREAS. THE MOST DOMINANT FEATURES  
INCLUDE A STRONG RIDGE CENTERED JUST OFF THE COAST OF SOUTHEAST ALASKA, A  
STRONG MID-LEVEL LOW TO ITS NORTH OVER THE ARCTIC OCEAN, AND A BROAD ANOMALOUS  
TROUGH OVER THE EASTERN CONUS. A COMPLEX PATTERN IS FORECAST UPSTREAM OVER THE  
PACIFIC AS A TROUGH IS PREDICTED WELL SOUTH OF THE GULF OF ALASKA, UNDERCUTTING  
THE RIDGE TO ITS NORTH. A SECOND, WEAKER TROUGH IS PREDICTED FURTHER TO THE  
SOUTH, JUST OFF THE WEST COAST OF THE CONUS. DOWNSTREAM OF NORTH AMERICA,  
ANOMALOUS RIDGING IS PREDICTED OVER THE NORTH ATLANTIC EXTENDING NORTHWARD TO  
JUST OFF THE COAST OF ATLANTIC CANADA. FARTHER TO THE SOUTH, SUBTROPICAL  
RIDGING IS FORECAST ALONG MUCH OF THE SOUTHERN TIER OF THE CONUS, CENTERED FROM  
THE RIO GRAND VALLEY TO THE WESTERN GULF COAST REGION. THE ECMWF ENSEMBLE MEAN  
DEPICTS A WEAKNESS IN THIS SUBTROPICAL RIDGE OVER THE SOUTHEAST.  
 
A STRONG RIDGE FORECAST NEAR SOUTHEASTERN ALASKA FAVORS ABOVE-NORMAL  
TEMPERATURES FOR THE SOUTHERN AND CENTRAL MAINLAND, SOUTHEAST ALASKA, AND  
SOUTHWARD TO THE NORTHWESTERN CONUS. PROBABILITIES OF ABOVE-NORMAL TEMPERATURES  
EXCEED 80 PERCENT FOR MUCH OF WASHINGTON STATE. BELOW-NORMAL TEMPERATURES ARE  
FAVORED FOR THE ALASKA NORTH SLOPE NEAR A PREDICTED ANOMALOUS MID-LEVEL LOW  
OVER THE ADJACENT ARCTIC OCEAN. FARTHER TO THE SOUTH, NEAR-NORMAL TEMPERATURES  
ARE MORE LIKELY ACROSS MUCH OF SOUTHERN CALIFORNIA INTO THE SOUTHWEST AND GREAT  
BASIN ASSOCIATED WITH WEAK TROUGHING FORECAST JUST OFF THE COAST AND DUE TO THE  
POTENTIAL FOR INCREASED CLOUDINESS. BELOW-NORMAL TEMPERATURES ARE LIKELY FROM  
MOST OF THE EASTERN SEABOARD WESTWARD TO MUCH OF THE PLAINS DUE TO ANOMALOUS  
TROUGHING CENTERED OVER THE EASTERN GREAT LAKES. CHANCES OF BELOW-NORMAL  
TEMPERATURES EXCEED 80 PERCENT FOR THE OHIO VALLEY, SOUTHERN GREAT LAKES,  
MIDDLE MISSISSIPPI VALLEY, AND ADJACENT AREAS OF THE CENTRAL PLAINS.  
ABOVE-NORMAL TEMPERATURES ARE MORE LIKELY FARTHER TO THE SOUTH, FOR THE FLORIDA  
PENINSULA, SOUTHERN PORTIONS OF THE SOUTHERN PLAINS, THE RIO GRAND VALLEY, AND  
SOUTHEASTERN PARTS OF THE SOUTHWEST DUE TO PREDICTED SUBTROPICAL RIDGING.  
INCREASED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE INDICATED FOR WESTERN  
AND CENTRAL PORTIONS OF HAWAII DRIVEN MOSTLY BY OBSERVED POSITIVE SEA SURFACE  
TEMPERATURES ANOMALIES IN THE ADJACENT PACIFIC.  
 
ABOVE-NORMAL PRECIPITATION IS FAVORED FOR A BROAD AREA OF THE INTERIOR WEST  
AHEAD OF A TROUGH PREDICTED OFF THE WEST COAST AND ASSOCIATED WITH POTENTIAL  
INFLUXES OF MONSOONAL MOISTURE. INCREASED CHANCES OF ABOVE-NORMAL PRECIPITATION  
EXTENDS EASTWARD TO MUCH OF THE SOUTHERN PLAINS, ASSOCIATED WITH A PREDICTED  
STATIONARY FRONTAL BOUNDARY. BELOW-NORMAL PRECIPITATION IS MORE LIKELY ACROSS  
THE UPPER MISSISSIPPI VALLEY, THE WESTERN GREAT LAKES, MUCH OF THE OHIO VALLEY,  
AND PARTS OF THE NORTHERN PLAINS ASSOCIATED WITH A PREDICTED SURFACE HIGH  
PRESSURE AND ASSOCIATED STABLE CANADIAN AIRMASS. ABOVE-NORMAL PRECIPITATION IS  
SLIGHTLY FAVORED ALONG THE EAST COAST, AHEAD OF A PREDICTED TROUGH CENTERED  
OVER THE EASTERN GREAT LAKES. BELOW-NORMAL PRECIPITATION IS LIKELY FROM  
SOUTHEASTERN ALASKA TO THE PACIFIC NORTHWEST DUE TO PREDICTED EXPANSIVE  
RIDGING. AN ACTIVE PATTERN IS MORE LIKELY FOR THE REMAINDER OF ALASKA AHEAD OF  
A MEAN TROUGH PREDICTED NEAR THE CHUKCHI PENINSULA. BELOW-NORMAL PRECIPITATION  
IS MORE LIKELY FOR PARTS OF THE BIG ISLAND OF HAWAII ASSOCIATED WITH PREDICTED  
ANOMALOUS RIDGING CENTERED TO THE EAST OF THE ISLAND CHAIN.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 20% OF TODAY'S 0Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 50% 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 TODAY’S ENSEMBLE MEANS.  
 
8-14 DAY OUTLOOK FOR AUG 27 - SEP 02, 2025  
 
THE WEEK-2 PERIOD FEATURES A MARKED REDUCTION IN AMPLITUDE OF MOST OF THE MAIN  
FEATURES DESCRIBED IN THE 6-10 DAY DISCUSSION. HOWEVER THERE IS LITTLE CHANGE  
IN THE LOCATION OF THESE FEATURES BETWEEN THE TWO OUTLOOK PERIODS. AN ANOMALOUS  
RIDGE IS FORECAST TO WEAKEN AND PUSH SLIGHTLY INLAND NEAR SOUTHEAST ALASKA AND  
EXTEND SOUTHWARD TO THE PACIFIC NORTHWEST AND NORTHERN ROCKIES. A MID-LEVEL LOW  
TO THE NORTH OF ALASKA IS FORECAST TO SIGNIFICANTLY WEAKEN. FARTHER TO THE  
SOUTH, PERSISTENT BUT SHALLOW TROUGHING IS PREDICTED OFF THE WEST COAST OF THE  
CONUS. A TROUGH IS FORECAST TO PERSIST OVER THE EASTERN GREAT LAKES WELL INTO  
WEEK-2 BUT SLOWLY WEAKEN. SUBTROPICAL RIDGING OF TYPICAL STRENGTH FOR THIS TIME  
OF YEAR IS FORECAST ACROSS MUCH OF THE SOUTHERN TIER OF THE CONUS. GENERALLY  
NEAR TO ABOVE-NORMAL 500-HPA HEIGHTS ARE FORECAST FOR HAWAII DUE TO PREDICTED  
ANOMALOUS RIDGING TO THE EAST OF THE STATE EARLY IN THE PERIOD FOLLOWED BY THE  
POTENTIAL DEVELOPMENT OF ANOTHER RIDGE NORTHWEST OF THE STATE LATER IN WEEK-2.  
 
PERSISTENT RIDGING OVER WESTERN CANADA FAVORS ABOVE-NORMAL TEMPERATURES ACROSS  
MUCH OF NEARBY ALASKA AND THE NORTHWESTERN CONUS. ABOVE-NORMAL TEMPERATURE  
PROBABILITIES EXCEED 60 PERCENT FOR WASHINGTON STATE AND ADJACENT AREAS OF  
NORTHERN OREGON. BELOW-NORMAL TEMPERATURES ARE MORE LIKELY ACROSS MUCH OF THE  
CENTRAL AND EASTERN CONUS DUE TO A PREDICTED ANOMALOUS TROUGH CENTERED NEAR THE  
GREAT LAKES. PROBABILITIES OF BELOW-NORMAL TEMPERATURES EXCEED 60 PERCENT FOR  
MUCH OF THE OHIO AND MIDDLE MISSISSIPPI VALLEYS AND ADJACENT CENTRAL PLAINS.  
ABOVE-NORMAL TEMPERATURES ARE MORE LIKELY TO THE SOUTH OF THIS TROUGH, FOR THE  
FLORIDA PENINSULA AND SOUTHERN TEXAS, ASSOCIATED WITH SUBTROPICAL RIDGING.  
ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR HAWAII DUE MOSTLY TO POSITIVE SST  
ANOMALIES IN THE ADJACENT PACIFIC OCEAN.  
 
A WET PATTERN CONTINUES TO BE LIKELY FOR MUCH OF THE INTERIOR WEST, CONSISTENT  
WITH TELECONNECTIONS FROM AN UPSTREAM RIDGE CENTERED OVER WESTERN CANADA.  
PRECIPITATION AMOUNTS ACROSS THE PARTS OF THE SOUTHWEST AND GREAT BASIN MAY BE  
ENHANCED DUE TO THE ADVECTION OF MONSOONAL MOISTURE INTO THE REGION. THE AREA  
OF INCREASED ABOVE-NORMAL PRECIPITATION CHANCES EXTENDS TO PARTS OF THE  
SOUTHERN AND CENTRAL PLAINS DUE TO THE POTENTIAL OF A MEAN FRONTAL BOUNDARY IN  
THE VICINITY. DRIER THAN NORMAL CONDITIONS ARE MORE LIKELY WELL TO THE NORTH  
AND WEST OF THIS BOUNDARY, ACROSS THE GREAT LAKES AND OHIO VALLEY AS SURFACE  
HIGH PRESSURE ASSOCIATED WITH A CANADIAN AIRMASS SETTLES IN. ABOVE-NORMAL  
PRECIPITATION IS FAVORED ALONG THE IMMEDIATE EAST COAST AHEAD OF THE MEAN  
TROUGH PREDICTED OVER THE EASTERN GREAT LAKES. STRONG RIDGING LEADS TO  
INCREASED CHANCES OF BELOW-NORMAL PRECIPITATION ACROSS SOUTHEAST ALASKA. AN  
ACTIVE PATTERN IS MORE LIKELY FOR MOST OF THE REMAINDER OF THE STATE AHEAD OF A  
TROUGH FORECAST NEAR THE CHUKCHI PENINSULA. A SLIGHT TILT TOWARD BELOW-NORMAL  
PRECIPITATION IS FORECAST FOR THE BIG ISLAND OF HAWAII DUE TO PREDICTED  
ANOMALOUS RIDGING TO THE EAST OF THE STATE EARLY IN THE PERIOD. NEAR-NORMAL  
PRECIPITATION IS FAVORED FOR THE REMAINDER OF THE ISLAND CHAIN FARTHER AWAY  
FROM THE RIDGE CENTER.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 25% OF TODAY'S 6Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, 50% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 11, AND 25% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON  
DAY 11  
 
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD  
MODEL AGREEMENT ON THE 500-HPA PATTERN EARLY IN THE PERIOD, OFFSET BY INCREASED  
UNCERTAINTY AND DECREASED PATTERN AMPLIFICATION LATER IN WEEK-2.  
 
 
FORECASTER: SCOTT 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 21.  
 
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:  
19910828 - 20010804 - 20010822 - 19600902 - 19950816  
 
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:  
19910828 - 19600901 - 19950818 - 19690821 - 19990815  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR AUG 25 - 29 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A B OREGON A A NRN CALIF A N  
SRN CALIF N A IDAHO A A NEVADA A A  
W MONTANA A N E MONTANA N N WYOMING N A  
UTAH N A ARIZONA N A COLORADO B A  
NEW MEXICO N A N DAKOTA B B S DAKOTA B N  
NEBRASKA B N KANSAS B N OKLAHOMA B A  
N TEXAS B A S TEXAS A A W TEXAS A A  
MINNESOTA B B IOWA B B MISSOURI B N  
ARKANSAS B N LOUISIANA N N WISCONSIN B B  
ILLINOIS B B MISSISSIPPI B N MICHIGAN B B  
INDIANA B B OHIO B B KENTUCKY B N  
TENNESSEE B N ALABAMA B N NEW YORK B A  
VERMONT B A NEW HAMP B A MAINE B A  
MASS B A CONN B A RHODE IS B A  
PENN B N NEW JERSEY B A W VIRGINIA B N  
MARYLAND B N DELAWARE B A VIRGINIA B N  
N CAROLINA B A S CAROLINA B A GEORGIA B N  
FL PNHDL N N FL PENIN A A AK N SLOPE B A  
AK ALEUTIAN A A AK WESTERN A A AK INT BSN N A  
AK S INT A A AK SO COAST A N AK PNHDL A B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR AUG 27 - SEP 02, 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A N  
SRN CALIF N A IDAHO A A NEVADA N A  
W MONTANA A A E MONTANA N N WYOMING N A  
UTAH N A ARIZONA N A COLORADO B A  
NEW MEXICO N A N DAKOTA B N S DAKOTA B N  
NEBRASKA B N KANSAS B A OKLAHOMA B A  
N TEXAS N A S TEXAS N N W TEXAS N A  
MINNESOTA B B IOWA B N MISSOURI B N  
ARKANSAS B A LOUISIANA N N WISCONSIN B B  
ILLINOIS B N MISSISSIPPI B N MICHIGAN B B  
INDIANA B B OHIO B B KENTUCKY B B  
TENNESSEE B B ALABAMA B N NEW YORK B N  
VERMONT B N NEW HAMP B A MAINE B A  
MASS B A CONN B A RHODE IS B A  
PENN B B NEW JERSEY B N W VIRGINIA B B  
MARYLAND B N DELAWARE B N VIRGINIA B N  
N CAROLINA B A S CAROLINA B N GEORGIA N N  
FL PNHDL N N FL PENIN A A AK N SLOPE N A  
AK ALEUTIAN A 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.  
 
 
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