487  
FXUS06 KWBC 161902  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT THU OCTOBER 16 2025  
 
6-10 DAY OUTLOOK FOR OCT 22 - 26 2025  
 
THERE IS GOOD AGREEMENT AMONG THE 0Z ECENS, GEFS, AND CMCE MODELS REGARDING AN  
AMPLIFIED 500-HPA HEIGHT PATTERN ACROSS NORTH AMERICA DURING THE 6-10 DAY  
PERIOD. COMPARED TO YESTERDAY, THE MODELS ARE MORE AMPLIFIED WITH INITIAL  
TROUGHING ACROSS THE NORTHEAST REFLECTIVE OF THE NEGATIVE PHASE OF THE NORTH  
ATLANTIC OSCILLATION (-NAO). THE TROUGHING IS FORECAST TO WEAKEN WITH TIME AS  
THE MEAN RIDGE AXIS SHIFTS EASTWARD OVER THE EAST-CENTRAL CONUS. DEEP TROUGHING  
IS FORECAST ACROSS THE GULF OF ALASKA, EXTENDING INTO THE NORTHEAST PACIFIC AND  
WESTERN CONUS. TODAY'S 6-10 DAY MANUAL 500-HPA HEIGHT BLEND DEPICTS  
BELOW-NORMAL HEIGHTS ACROSS MUCH OF THE EASTERN THIRD OF THE CONUS, WITH THE  
LARGEST MAGNITUDE (-60 METERS) OVER THE NORTHEAST. ABOVE-NORMAL HEIGHTS ARE  
INDICATED ACROSS THE INTERIOR WEST EASTWARD THROUGH MUCH OF THE GREAT PLAINS  
INTO THE MISSISSIPPI VALLEY. THE HIGH AMPLITUDE TROUGHING OVER WESTERN NORTH  
AMERICA RESULTS IN A BROAD REGION OF BELOW-NORMAL HEIGHTS EXTENDING FROM ALASKA  
TO THE WEST COAST OF THE CONUS. ABOVE-NORMAL HEIGHTS ARE FORECAST ACROSS HAWAII.  
 
THE AMPLIFIED TROUGHING ACROSS THE EASTERN U.S. SUPPORTS AN INCREASE IN THE  
PROBABILITIES FOR BELOW-NORMAL TEMPERATURES OVER THE REGION. THE UNCALIBRATED  
ECENS AND GEFS, AND TO SOME DEGREE, THE REFORECAST TOOLS ARE SUPPORTIVE OF THE  
FORECAST TRENDING COOLER RELATIVE TO YESTERDAY. ELSEWHERE ACROSS THE CONUS,  
PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE ELEVATED, WITH THE HIGHEST  
CHANCES (GREATER THAN 60 PERCENT) OVER THE GREAT PLAINS. INCREASING PACIFIC  
FLOW ACROSS THE WEST FAVORS AN INCREASE IN CLOUD COVER AND PRECIPITATION LATER  
IN THE PERIOD. THEREFORE, PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE LOWER  
THAN THOSE TO THE EAST, WITH NEAR-NORMAL TEMPERATURES MORE LIKELY OVER PARTS OF  
THE PACIFIC NORTHWEST AND SOUTHWEST. ENHANCED ODDS FOR NEAR- TO BELOW-NORMAL  
TEMPERATURES ARE FAVORED FOR MUCH OF ALASKA UNDERNEATH TROUGHING. THE EXCEPTION  
IS ACROSS THE NORTHEASTERN MAINLAND, WHERE ABOVE-NORMAL TEMPERATURE  
PROBABILITIES ARE INCREASED, SUPPORTED BY THE REFORECAST AND UNCALIBRATED  
FORECAST TOOLS. ABOVE-NORMAL TEMPERATURES ARE STRONGLY FAVORED ACROSS HAWAII  
TIED TO RIDGING AND POSITIVE HEIGHT ANOMALIES PREDICTED OVER THE SOUTH-CENTRAL  
PACIFIC.  
 
THE MAJOR STORY FOR THE PRECIPITATION OUTLOOK IS THE DEVELOPING ATMOSPHERIC  
RIVER EVENT ALONG THE U.S. WEST COAST TIED TO TROUGHING EXTENDING SOUTHWARD  
FROM ALASKA INTO THE NORTHEAST PACIFIC. WHILE THE OUTSET OF THE PERIOD IS  
FORECAST TO BE RELATIVELY DRY, PRECIPITATION SIGNALS INCREASE GREATLY BY DAYS 7  
AND 8. THE PATTERN SUPPORTS HIGH PROBABILITIES OF ABOVE-NORMAL PRECIPITATION  
ACROSS MUCH OF THE WEST. THE LARGEST PROBABILITIES (GREATER THAN 70 PERCENT)  
ARE FOCUSED ACROSS COASTAL OREGON AND NORTHWESTERN CALIFORNIA, WITH DECREASING  
PROBABILITIES ACROSS THE SOUTHWEST INTO THE SOUTHERN PLAINS. TIED TO INCREASED  
RIDGING AND SURFACE HIGH PRESSURE, ODDS FOR BELOW-NORMAL PRECIPITATION ARE  
INCREASED OVER MUCH OF THE NORTHERN HALF OF THE PLAINS, MIDWEST, AND INTO THE  
SOUTHEAST. THE TROUGH IN THE EAST AND ASSOCIATED CYCLONIC FLOW FAVORS A SLIGHT  
TILT TOWARD ABOVE-NORMAL PRECIPITATION CHANCES ACROSS NEW ENGLAND. NEAR- TO  
ABOVE-NORMAL PRECIPITATION CHANCES ARE INCREASED ACROSS ALASKA, ALTHOUGH THE  
STRONGEST SIGNALS ARE PREDICTED TO SHIFT TO THE SOUTH OF THE STATE BY THE END  
OF THE PERIOD. SLIGHTLY ELEVATED ABOVE-NORMAL PRECIPITATION PROBABILITIES ARE  
FORECAST ACROSS HAWAII, SUPPORTED BY THE CONSOLIDATION REFORECAST TOOL.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 0Z 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  
GENERALLY GOOD MODEL AGREEMENT, BUT OFFSET BY SOME UNCERTAINTY IN THE EAST  
GIVEN THE TREND TO MORE TROUGHING COMPARED TO YESTERDAY.  
 
8-14 DAY OUTLOOK FOR OCT 24 - 30 2025  
 
THE HIGH AMPLITUDE 500-HPA HEIGHT PATTERN IS FORECAST TO CONTINUE ACROSS  
WESTERN NORTH AMERICA DURING THE WEEK-2 PERIOD, WITH ANOMALOUS TROUGHING  
PERSISTING ACROSS THE NORTHEASTERN PACIFIC INTO THE WEST COAST. FURTHER  
DOWNSTREAM, THE PATTERN IS PREDICTED TO BE MORE TRANSIENT, WITH INITIAL RIDGING  
OVER THE EAST-CENTRAL CONUS BEING REPLACED BY SHORTWAVE TROUGHING. THE 0Z ECENS  
AND CMCE ARE MORE ROBUST WITH THIS FEATURE COMPARED TO THE 0Z GEFS. THE WEEK-2  
MANUAL HEIGHT BLEND DEPICTS BELOW-NORMAL HEIGHTS EXTENDING FROM ALASKA INTO THE  
NORTHWESTERN CONUS. CONVERSELY, LARGE ABOVE-NORMAL HEIGHT ANOMALIES ARE  
INDICATED OVER MUCH OF CENTRAL AND EASTERN CANADA, EXTENDING INTO PARTS OF THE  
NORTH-CENTRAL AND NORTHEASTERN CONUS. NEAR-NORMAL HEIGHTS ARE PREDICTED OVER  
MUCH OF THE SOUTH-CENTRAL AND SOUTHEASTERN CONUS. ELONGATED RIDGING OVER THE  
CENTRAL AND EASTERN PACIFIC SUPPORT ABOVE-NORMAL HEIGHTS EXTENDING FROM HAWAII  
INTO THE SOUTHWESTERN U.S.  
 
INCREASED PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE FORECAST ACROSS THE  
INTERIOR CONUS UNDERNEATH TRANSIENT RIDGING EARLY IN THE PERIOD AND GOOD  
SUPPORT FROM THE ECENS AND GEFS REFORECAST AND UNCALIBRATED TOOLS. THE LARGEST  
PROBABILITIES (GREATER THAN 70 PERCENT) ARE HIGHLIGHTED ACROSS THE NORTHERN  
PLAINS AND UPPER MISSISSIPPI VALLEY. AREAS OF NEAR-NORMAL TEMPERATURES ARE  
FORECAST ACROSS THE MID-ATLANTIC TIED TO TROUGHING AND A WEAK -NAO PERSISTING,  
AND OVER THE WEST DUE TO ENHANCED CLOUD COVER AND PRECIPITATION. THE  
TEMPERATURE FORECAST FOR ALASKA AND HAWAII IS VERY SIMILAR TO THAT OF THE 6-10  
DAY PERIOD. NEAR- TO BELOW-NORMAL TEMPERATURE PROBABILITIES ARE INCREASED FOR  
MUCH OF ALASKA UNDERNEATH TROUGHING, WITH HIGHER ODDS FOR ABOVE-NORMAL  
TEMPERATURES REMAINING ACROSS THE NORTHEASTERN MAINLAND. ABOVE-NORMAL  
TEMPERATURES CONTINUE TO BE STRONGLY FAVORED ACROSS HAWAII.  
 
THE ONGOING ATMOSPHERIC RIVER EVENT ACROSS THE WEST COAST CONTINUES TO FAVOR  
HIGH PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION ACROSS MUCH OF THE WEST. THE  
HIGHEST CHANCES (GREATER THAN 70 PERCENT) ARE FOCUSED ACROSS PORTIONS OF  
WESTERN OREGON AND NORTHWESTERN CALIFORNIA WHERE SEVERAL INCHES OF RAIN MAY  
FALL DURING THE WEEK-2 PERIOD BASED ON THE 0Z ECENS AND GEFS. ADDITIONAL  
SHORTWAVE TROUGHING AS DEPICTED IN THE 0Z ECENS AND CMCE FAVORS AN INCREASE IN  
THE ODDS FOR ABOVE-NORMAL PRECIPITATION ACROSS PORTIONS OF THE GREAT PLAINS  
INTO THE LOWER MISSISSIPPI VALLEY. SLIGHTLY BELOW-NORMAL PRECIPITATION CHANCES  
REMAIN ELEVATED ACROSS THE GREAT LAKES AND NORTHEAST FURTHER DISPLACED FROM  
THIS FEATURE. TROPICAL CYCLOGENESIS IS POSSIBLE ACROSS THE CARIBBEAN DURING  
WEEK-2, AND ANY SYSTEM THAT FORMS WILL NEED TO BE WATCHED AS CLIMATOLOGY  
GENERALLY FAVORS A RECURVING TRACK TO THE NORTH. CURRENTLY MOST LONG-RANGE  
MODEL SOLUTIONS FAVOR ANY SYSTEM REMAINING OVER THE WESTERN ATLANTIC, BUT  
CONFIDENCE IS LOW GIVEN THAT A SYSTEM HAS NOT YET FORMED. A DRYING TREND  
REMAINS FORECAST ACROSS ALASKA, WITH NEAR-NORMAL PRECIPITATION FAVORED ACROSS  
MOST OF THE STATE, WITH THE EXCEPTION OF PORTIONS OF THE ALEUTIANS, NORTHERN  
MAINLAND, AND SOUTHEAST ALASKA WHERE WEAK PROBABILITIES FOR ABOVE-NORMAL  
PRECIPITATION ARE FAVORED. A SLIGHT TILT TOWARD ENHANCED PROBABILITIES FOR  
ABOVE-NORMAL PRECIPITATION IS FORECAST FOR HAWAII.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 25% OF TODAY'S 0Z 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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO  
GOOD MODEL AGREEMENT REGARDING AN AMPLIFIED TROUGH NEAR THE WEST COAST OF THE  
CONUS, OFFSET BY GREATER UNCERTAINTY FURTHER DOWNSTREAM.  
 
FORECASTER: THOMAS COLLOW  
 
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON  
NOVEMBER 20.  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR OCT 22 - 26 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF N A IDAHO A A NEVADA A A  
W MONTANA A A 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 A OKLAHOMA A A  
N TEXAS A A S TEXAS A A W TEXAS A A  
MINNESOTA A B IOWA A B MISSOURI A B  
ARKANSAS N N LOUISIANA A N WISCONSIN A B  
ILLINOIS N B MISSISSIPPI N B MICHIGAN A B  
INDIANA N B OHIO B B KENTUCKY B B  
TENNESSEE B B ALABAMA N B NEW YORK N N  
VERMONT A A NEW HAMP A A MAINE A A  
MASS N A CONN N N RHODE IS N A  
PENN B N NEW JERSEY B N W VIRGINIA B B  
MARYLAND B N DELAWARE B N VIRGINIA B B  
N CAROLINA B B S CAROLINA B B GEORGIA B B  
FL PNHDL N B FL PENIN A N AK N SLOPE N A  
AK ALEUTIAN B A AK WESTERN B N AK INT BSN N A  
AK S INT N A AK SO COAST N A AK PNHDL B A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR OCT 24 - 30 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON N A OREGON N A NRN CALIF N A  
SRN CALIF N A IDAHO A A NEVADA N A  
W MONTANA A A E MONTANA A N WYOMING A N  
UTAH A A ARIZONA A N COLORADO A A  
NEW MEXICO A N N DAKOTA A N S DAKOTA A N  
NEBRASKA A N KANSAS A A OKLAHOMA A N  
N TEXAS A N S TEXAS A N W TEXAS A N  
MINNESOTA A N IOWA A N MISSOURI A N  
ARKANSAS A N LOUISIANA A N WISCONSIN A N  
ILLINOIS A N MISSISSIPPI A N MICHIGAN A B  
INDIANA A N OHIO A N KENTUCKY A N  
TENNESSEE A N ALABAMA A N NEW YORK A B  
VERMONT A B NEW HAMP A B MAINE A N  
MASS A B CONN A N RHODE IS A N  
PENN A N NEW JERSEY N N W VIRGINIA N N  
MARYLAND N N DELAWARE N N VIRGINIA N N  
N CAROLINA N N S CAROLINA N N GEORGIA A N  
FL PNHDL A N FL PENIN A N AK N SLOPE N A  
AK ALEUTIAN B A AK WESTERN B N AK INT BSN N N  
AK S INT N N AK SO COAST N N AK PNHDL B 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.  
 
 
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