682  
FXUS06 KWBC 151902  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EDT TUE SEPTEMBER 15 2026  
 
6-10 DAY OUTLOOK FOR SEP 21 - 25 2026  
 
TODAY'S DYNAMICAL MODELS DEPICT AN OMEGA-LIKE PATTERN WITH A RIDGE OVER  
SOUTH-CENTRAL CANADA BRACKETED BY TROUGHS OVER THE CANADIAN MARITIME PROVINCES  
AND NEAR THE WEST COAST. THE ANCHORING RIDGE BECOMES ESTABLISHED EARLY IN THE  
PERIOD AND GAINS STRENGTH THROUGH THE PERIOD. FARTHER TO THE SOUTH, A TROUGH OR  
CLOSED LOW IS FORECAST NEAR THE CENTRAL GULF COAST REGION WITH REMNANT WEAKNESS  
IN THE SUBTROPICAL RIDGE POTENTIALLY PERSISTING INTO WEEK-2. IN ALASKA, AN  
EARLY STRONG TROUGH IS FORECAST TO WEAKEN THROUGH THE PERIOD. THIS COULD BE AN  
INDICATION OF ENSEMBLE GUIDANCE STRUGGLING WITH THE EVENTUAL TRACK OF ANY  
RECURVING TROPICAL CYCLONES FROM THE WEST PACIFIC AND THE EFFECT ON THE  
LONGWAVE MID-LEVEL HEIGHT PATTERN. THIS COMPLEX FORECAST EVOLUTION IN ALASKA  
AND DOWNSTREAM ALONG THE WEST COAST RESULTS IN INCREASED MODEL SPREAD AND  
UNCERTAINTY ACROSS THE REGION. THE TROPICAL EASTERN AND CENTRAL PACIFIC REMAINS  
ACTIVE AND MAY INFLUENCE THE SENSIBLE WEATHER ACROSS HAWAII.  
 
ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS MOST OF THE CONUS, TIED TO  
PREDICTED WIDESPREAD ABOVE NORMAL MEAN MID-LEVEL HEIGHTS. A GREATER THAN 60  
PERCENT CHANCE FOR ABOVE NORMAL TEMPERATURES IS FORECAST ACROSS THE TENNESSEE  
VALLEY SOUTHWARD TO THE GULF COAST, IN THE WARM SECTOR AHEAD OF A DEVELOPING  
SURFACE LOW OVER THE CENTRAL PLAINS AND MIDDLE MISSISSIPPI VALLEY. MEANWHILE, A  
SECOND AREA OF CHANCES GREATER THAN 60 PERCENT CHANCES FORECAST FOR THE  
NORTHERN HIGH PLAINS, ASSOCIATED WITH THE RIDGE OVER SOUTH-CENTRAL CANADA.  
WEAKER CHANCES FOR ABOVE NORMAL TEMPERATURES ARE FORECAST ACROSS MUCH OF THE  
WEST DUE TO UNCERTAINTY SURROUNDING THE POTENTIAL EVOLUTION OF A CUT-OFF LOW  
NEAR THE COAST. NEAR NORMAL TEMPERATURES ARE MODESTLY FAVORED OVER PARTS OF  
NORTHERN NEW ENGLAND, ASSOCIATED WITH A TROUGH CENTERED NEAR ATLANTIC CANADA.  
BELOW NORMAL TEMPERATURES ARE LIKELY ACROSS WESTERN AND CENTRAL MAINLAND ALASKA  
AS WELL AS THE ALASKA PENINSULA DUE TO ANOMALOUS TROUGHING. ABOVE NORMAL  
TEMPERATURES ARE FAVORED FOR PARTS OF THE ALEUTIANS, ASSOCIATED WITH ABOVE  
NORMAL SEA SURFACE TEMPERATURES IN ADJACENT WATERS. ABOVE NORMAL TEMPERATURES  
ARE LIKELY ACROSS HAWAII DUE TO WIDESPREAD ABOVE NORMAL SSTS IN THE TROPICAL  
EASTERN AND CENTRAL PACIFIC ASSOCIATED WITH THE CURRENT EL NINO.  
 
INCREASED TROPICAL MOISTURE ADVECTION AND CYCLONIC FLOW CONTINUE TO RESULT IN  
ELEVATED PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION ACROSS SOUTHERN AND  
CENTRAL SECTIONS OF THE WESTERN CONUS. THE HIGHEST PROBABILITIES (GREATER THAN  
50 PERCENT) ARE FOCUSED ACROSS THE SOUTHWEST AND ADJACENT AREAS. A TILT TOWARD  
BELOW NORMAL PRECIPITATION IS INDICATED FOR THE UPPER MISSISSIPPI VALLEY AND  
WESTERN GREAT LAKES, DUE TO PREDICTED SURFACE HIGH PRESSURE. ENHANCED  
NORTHEASTERLY MARITIME FLOW ON THE SOUTHERN AND EASTERN FRINGE OF THIS SURFACE  
HIGH FAVORS ABOVE NORMAL PRECIPITATION ALONG MUCH OF THE EASTERN SEABOARD.  
ADDITIONALLY, THE POTENTIAL FOR A SHORTWAVE TROUGH LEADS TO ELEVATED CHANCES OF  
ABOVE NORMAL PRECIPITATION ACROSS THE SOUTHEASTERN QUADRANT OF THE CONUS.  
PERSISTENT CYCLONIC FLOW AND ASSOCIATED SURFACE LOW PRESSURE FAVORS ABOVE  
NORMAL PRECIPITATION ACROSS MOST OF EASTERN AND CENTRAL ALASKA. AN ACTIVE  
EASTERN AND CENTRAL TROPICAL PACIFIC FAVORS ABOVE NORMAL PRECIPITATION ACROSS  
HAWAII. PLEASE STAY TUNED TO THE NATIONAL HURRICANE CENTER FOR THE LATEST  
DEVELOPMENTS IN THE TROPICS.  
 
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: AVERAGE, 3 OUT OF 5, DUE TO GOOD  
MODEL AGREEMENT REGARDING AN EVOLUTION TOWARD AN OMEGA-LIKE PATTERN OFFSET BY  
LARGE MODEL UNCERTAINTY REGARDING THE EVOLUTION OF INDIVIDUAL FEATURES,  
ESPECIALLY ALONG THE WEST COAST.  
 
8-14 DAY OUTLOOK FOR SEP 23 - 29 2026  
 
BY THE BEGINNING OF WEEK-2, AN OMEGA-LIKE PATTERN IS FORECAST WITH ANOMALOUS  
RIDGING PREDICTED OVER SOUTH-CENTRAL CANADA. HOWEVER, THERE ARE DIFFERENCES  
BETWEEN THE EVOLUTION OF THE MID-LEVEL HEIGHT PATTERN AMONG THE DYNAMICAL MODEL  
GUIDANCE. THE ECENS AND CMCE MAINTAIN A STRONGER RIDGE CENTER OVER CENTRAL AND  
EASTERN CANADA WITH MORE TROUGHING ALONG THE WEST COAST OF NORTH AMERICA.  
MEANWHILE, THE GEFS HAS A WEAKER AND MORE TRANSIENT RIDGE ACROSS CANADA AND  
BRINGS AN ADDITIONAL QUICK MOVING POSITIVE HEIGHT ANOMALY INTO THE WESTERN US.  
IN LIGHT OF THE STRONGER AGREEMENT BETWEEN THE ECENS AND CMCE, THIS IS THE  
FAVORED SOLUTION IN THE MANUAL 500-HPA HEIGHT BLEND. IN ALASKA, THE PATTERN IS  
QUITE UNCERTAIN WITH MID-LEVEL HEIGHTS RISING TO BE NEAR-NORMAL WITH TIME.  
HAWAII WILL CONTINUE TO BE SUSCEPTIBLE TO INFLUXES OF TROPICAL ACTIVITY AS THE  
TROPICAL EASTERN AND CENTRAL PACIFIC REMAIN ACTIVE.  
 
WITH THE ECENS AND CMCE FORECASTING A STABLE EXPANSIVE RIDGE FORECAST OVER  
SOUTH-CENTRAL CANADA, ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS MOST OF THE  
CONUS. THE STRONGEST CHANCES ARE FORECAST OVER THE UPPER MISSISSIPPI VALLEY,  
UPPER GREAT LAKES, AND NORTHERN PLAINS AND SEPARATELY OVER THE WESTERN GULF  
COAST WHERE PROBABILITIES EXCEED 60%. CONFIDENCE IS LOWER OVER THE WESTERN  
CONUS WHERE DIFFERENCES AMONG THE DYNAMICAL MODELS AND STATISTICAL GUIDANCE  
LEAD TO A SLIGHT TILT TOWARDS ABOVE NORMAL TEMPERATURES. WEAKER CHANCES FOR  
ABOVE NORMAL TEMPERATURES IS ALSO FOUND OVER THE NORTHEAST AND MID-ATLANTIC,  
CLOSER TO MID-LEVEL TROUGHING AND CHANCES FOR ONSHORE FLOW AROUND THE SOUTHERN  
PERIPHERY OF THE MID-LEVEL RIDGING. IN ALASKA, A SLIGHT TILT TOWARDS BELOW  
NORMAL TEMPERATURES IS FAVORED WITH THE MID-LEVEL HEIGHT PATTERN BREAKING DOWN  
OVER THE STATE. ABOVE NORMAL TEMPERATURES REMAIN LIKELY ACROSS HAWAII.  
 
A CONTINUED ACTIVE PATTERN IS FAVORED ACROSS THE WEST, DUE TO THE COMBINATION  
OF CYCLONIC FLOW ALONG THE COAST AND POTENTIAL ADVECTION OF MOISTURE FROM AN  
ACTIVE EASTERN TROPICAL PACIFIC. BELOW NORMAL PRECIPITATION IS FAVORED FARTHER  
TO THE EAST, ACROSS THE GREAT LAKES, THE NORTHERN HALF OF THE MISSISSIPPI  
VALLEY AND INTERIOR PORTIONS OF THE NORTHEAST, ASSOCIATED WITH PREDICTED  
SURFACE HIGH PRESSURE. ABOVE NORMAL PRECIPITATION IS FAVORED TO THE SOUTH AND  
EAST OF THIS SURFACE HIGH, ASSOCIATED WITH ENHANCED NORTHEASTERLY OR EASTERLY  
MARITIME FLOW. IN ALASKA, ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED  
CONSISTENT WITH THE REFORECAST GUIDANCE. PROBABILITIES OF ABOVE NORMAL  
PRECIPITATION ALSO EXCEED 50 PERCENT ACROSS THE EASTERN ISLANDS OF HAWAII, AS  
THE TROPICAL PACIFIC IS FAVORED TO REMAIN ACTIVE.  
 
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: BELOW AVERAGE, 2 OUT OF 5, DUE TO  
A PREDICTED COMPLEX PATTERN OVER THE WESTERN CONUS AND ELEVATED UNCERTAINTY  
REGARDING THE EVOLUTION OF THE TROPICS.  
 
FORECASTER: RYAN BOLT  
 
NOTES:  
 
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 (GRAY, "N") NORMAL.  
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 (GRAY, "N")  
NORMAL. 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  
SEPTEMBER 17.  
 
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:  
20180921 - 20190928 - 20050922 - 20200912 - 20180829  
 
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:  
20180923 - 20200912 - 20190928 - 20180830 - 19900826  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR SEP 21 - 25 2026  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A N OREGON A N NRN CALIF A A  
SRN CALIF A A IDAHO A N NEVADA A A  
W MONTANA A N E MONTANA A N WYOMING A A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA A B S DAKOTA A N  
NEBRASKA A A KANSAS A A OKLAHOMA A A  
N TEXAS A A S TEXAS A A W TEXAS A A  
MINNESOTA A B IOWA A N MISSOURI A N  
ARKANSAS A A LOUISIANA A A WISCONSIN A B  
ILLINOIS A N MISSISSIPPI A A MICHIGAN A B  
INDIANA A N OHIO A N KENTUCKY A A  
TENNESSEE A A ALABAMA A A NEW YORK A N  
VERMONT A N NEW HAMP A A MAINE N N  
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 A FL PENIN A A AK N SLOPE B A  
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A  
AK S INT B A AK SO COAST B A AK PNHDL N A  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR SEP 23 - 29 2026  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A N OREGON N A NRN CALIF A A  
SRN CALIF A A IDAHO A A NEVADA A A  
W MONTANA A A E MONTANA A A WYOMING A A  
UTAH A A ARIZONA A A COLORADO A A  
NEW MEXICO A A N DAKOTA A 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 A  
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 N  
INDIANA A N OHIO A N KENTUCKY A N  
TENNESSEE A N ALABAMA A A NEW YORK A N  
VERMONT A N NEW HAMP A N MAINE A N  
MASS A N CONN A A RHODE IS A A  
PENN A N 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 N N  
AK ALEUTIAN A N AK WESTERN B N AK INT BSN N N  
AK S INT N N AK SO COAST N N AK PNHDL N 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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