969
FXUS06 KWBC 092105
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 09 2025
6-10 DAY OUTLOOK FOR OCT 15 - 19 2025
DYNAMICAL MODELS REMAIN IN GOOD AGREEMENT REGARDING THE PREDICTED 500-HPA
HEIGHT PATTERN DURING THE 6-10 DAY PERIOD. A NEGATIVE NORTH ATLANTIC
OSCILLATION (-NAO) IS FORECAST TO DEVELOP IN CONJUNCTION WITH STRONG RIDGING
NEAR GREENLAND, AND TROUGHING OVER THE NORTHWEST ATLANTIC, ASSOCIATED WITH A
DEPARTING COASTAL STORM THAT IS ANTICIPATED TO IMPACT THE EAST COAST PRIOR TO
THE START OF THE PERIOD. UPSTREAM, RIDGING IS FORECAST ACROSS THE CENTRAL
CONUS. AT THE OUTSET OF THE PERIOD, ANOMALOUS RIDGING AND TROUGHING IS
PREDICTED ACROSS SOUTHEAST ALASKA AND THE WEST COAST OF THE CONUS RESPECTIVELY,
WITH A GRADUAL WEAKENING OF THESE FEATURES LATER IN THE PERIOD. ADDITIONAL
TROUGHING IS FORECAST TO PROGRESS FROM EASTERN RUSSIA INTO THE BERING SEA AND
WESTERN ALASKA BY DAY-10. TODAYS MANUAL 6-10 DAY 500-HPA HEIGHT BLEND DEPICTS
ABOVE-NORMAL HEIGHTS ACROSS EASTERN ALASKA EXTENDING ACROSS THE NORTHWESTERN
CONUS ALONG THE CANADIAN BORDER, AND INTO MUCH OF THE CENTRAL CONUS.
CONVERSELY, BELOW-NORMAL HEIGHTS ARE INDICATED ACROSS MUCH OF WESTERN ALASKA,
INCLUDING THE ALEUTIANS, PARTS OF THE SOUTHWESTERN CONUS AND GREAT BASIN, AND
THE MID-ATLANTIC AND NORTHEAST. NEAR-NORMAL HEIGHTS ARE FORECAST ACROSS HAWAII,
WITH A WEAKNESS PROGRESSING ACROSS THE NORTHERN ISLANDS AROUND OR JUST BEFORE
THE START OF THE PERIOD.
INCREASED CHANCES FOR BELOW-NORMAL TEMPERATURES ARE FAVORED ACROSS THE CONUS
WEST OF THE ROCKIES DUE TO THE INFLUENCE OF TROUGHING, ESPECIALLY EARLY IN THE
PERIOD. INCREASING PACIFIC FLOW LATER IN THE PERIOD MAY HELP MODERATE
TEMPERATURES ACROSS THE NORTHWEST WHERE PROBABILITIES FOR BELOW-NORMAL
TEMPERATURES ARE LOWER COMPARED TO FARTHER SOUTH. CONVERSELY, ABOVE-NORMAL
TEMPERATURES ARE STRONGLY FAVORED ACROSS THE CENTRAL CONUS TIED TO RIDGING,
WITH THE HIGHEST PROBABILITIES (GREATER THAN 80 PERCENT) ACROSS NORTH-CENTRAL
TEXAS. DAILY TEMPERATURE ANOMALIES EXCEEDING +10 DEG F ARE POSSIBLE OVER PARTS
OF THE CENTRAL AND SOUTHERN PLAINS INTO ADJACENT AREAS OF THE MISSISSIPPI
VALLEY BASED ON THE UNCALIBRATED 0Z ECENS AND GEFS. WHILE THE REFORECAST TOOLS
LEAN WARMER COMPARED TO THE UNCALIBRATED TOOLS ACROSS THE MID-ATLANTIC AND
NORTHEAST, ANALOGS AND TELECONNECTIONS AS WELL AS THE EVOLVING -NAO FAVOR
ENHANCED CHANCES OF BELOW-NORMAL TEMPERATURES. STRONG SOUTHERLY FLOW AT THE
SURFACE AND ALOFT DUE TO TROUGHING OVER THE BERING SEA AND RIDGING OVER
SOUTHEAST ALASKA SUPPORT HIGH PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES
ACROSS ALASKA. ABOVE-NORMAL TEMPERATURES ARE ALSO FORECAST ACROSS HAWAII
SUPPORTED BY THE CONSOLIDATION REFORECAST TOOL.
TROUGHING IN THE WEST ALONG WITH INCREASED MOISTURE ADVECTION FROM THE TROPICAL
EAST PACIFIC FAVOR ELEVATED CHANCES FOR ABOVE-NORMAL PRECIPITATION EXTENDING
FROM THE SOUTHWEST TO THE NORTHERN PLAINS WITH MODELS INDICATING SOME POTENTIAL
FOR LEE CYCLOGENESIS EARLY IN THE PERIOD. PROBABILITIES FOR BELOW-NORMAL
PRECIPITATION ARE INCREASED ACROSS PORTIONS OF THE FAR NORTHWESTERN CONUS
CLOSER TO THE POSITIVE HEIGHT ANOMALY CENTER OVER SOUTHEAST ALASKA. THERE IS A
STRONG SIGNAL FOR BELOW-NORMAL PRECIPITATION IN NEARLY ALL OF THE FORECAST
TOOLS ACROSS THE SOUTHERN PLAINS INTO MUCH OF THE SOUTHEASTERN CONUS EXTENDING
NORTH INTO THE OHIO VALLEY TIED TO SURFACE HIGH PRESSURE. 6-10 PRECIPITATION
TOTALS FROM THE 0Z ECENS, GEFS, AND CMCE ARE GENERALLY LESS THAN A QUARTER-INCH
ACROSS MUCH OF THE SOUTH-CENTRAL AND SOUTHEASTERN CONUS. THIS SUPPORTS
INCREASED CHANCES OF BELOW-NORMAL PRECIPITATION IN THE FORECAST, WITH THE
HIGHEST CHANCES (GREATER THAN 60 PERCENT) EXTENDING FROM EASTERN TEXAS THROUGH
THE NORTHERN GULF COAST STATES. SOME RESIDUAL MOISTURE FROM A DEPARTING COASTAL
LOW IS POSSIBLE ACROSS EASTERN NEW ENGLAND SLIGHTLY TILTING THE ODDS TO
ABOVE-NORMAL PRECIPITATION. TROUGHING ACROSS THE BERING SEA AND POTENTIAL
SURFACE LOW PRESSURE FAVORS ENHANCED PROBABILITIES FOR ABOVE-NORMAL
PRECIPITATION OVER MUCH OF ALASKA, INCREASING TO THE WEST. ELEVATED CHANCES FOR
BELOW-NORMAL PRECIPITATION REMAIN ACROSS PARTS OF SOUTHEAST ALASKA TIED TO
PREDICTED RIDGING ACROSS THE REGION. ABOVE-NORMAL PRECIPITATION IS FORECAST
ACROSS HAWAII, WITH HIGHER PROBABILITIES ACROSS THE NORTHERN ISLANDS.
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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT IN DEPICTING AN AMPLIFIED 500-HPA PATTERN ACROSS MUCH OF
THE FORECAST DOMAIN.
8-14 DAY OUTLOOK FOR OCT 17 - 23 2025
DURING WEEK-2, THE 500-HPA HEIGHT PATTERN ACROSS THE CONUS IS PREDICTED TO
DE-AMPLIFY, WITH SOME WEAKENING OF THE -NAO. THE 0Z ECENS, GEFS, AND CMCE ARE
IN GOOD AGREEMENT REGARDING TROUGHING SPREADING FROM WESTERN ALASKA
SOUTHEASTWARD THROUGH THE GULF OF ALASKA AND NORTHEAST PACIFIC LATER IN THE
PERIOD RESULTING IN HEIGHT FALLS AND INCREASING ONSHORE FLOW ACROSS SOUTHEAST
ALASKA AND THE PACIFIC NORTHWEST. TODAYS WEEK-2 MANUAL HEIGHT BLEND IS
GENERALLY TIED TO STRONGER ANOMALIES EARLIER IN THE PERIOD, AND IS ALSO SIMILAR
TO THAT OF THE 6-10 DAY PERIOD, EXCEPT WEAKER IN MAGNITUDE AS A FASTER, MORE
PROGRESSIVE MID-LEVEL FLOW PATTERN DEVELOPS OVER THE CONUS. ABOVE-NORMAL
HEIGHTS ARE DEPICTED ACROSS EASTERN ALASKA AND OVER THE CENTRAL CONUS. AREAS OF
NEAR-TO BELOW-NORMAL HEIGHTS ARE INDICATED ACROSS WESTERN ALASKA, THE WESTERN
CONUS, AND OVER THE MID-ATLANTIC AND NORTHEAST. NEAR-NORMAL HEIGHTS ARE
FORECAST ACROSS HAWAII.
THE WEEK-2 TEMPERATURES OUTLOOK IS SIMILAR TO THE 6-10 DAY OUTLOOK, WITH THE
LARGEST CHANGE BEING A TREND TOWARD WARMER TEMPERATURES ACROSS THE WEST,
PARTICULARLY THE NORTHWEST, AS PACIFIC FLOW INCREASES AHEAD OF TROUGHING MOVING
INTO THE NORTHEAST PACIFIC. THIS SLIGHTLY TILTS THE ODDS TOWARD ABOVE-NORMAL
TEMPERATURES ACROSS THE PACIFIC NORTHWEST, WITH ELEVATED CHANCES FOR
BELOW-NORMAL TEMPERATURES REMAINING OVER PARTS OF THE SOUTHWEST. INCREASED
CHANCES OF ABOVE-NORMAL TEMPERATURES ARE FORECAST FOR MUCH OF THE CENTRAL AND
SOUTHEASTERN CONUS SUPPORTED BY THE GEFS AND ECENS REFORECAST TOOLS AND TIED TO
ENHANCED RIDGING EARLY IN THE PERIOD. AS DISCUSSED IN THE 6-10 OUTLOOK, THE
-NAO ALONG WITH UNCALIBRATED GUIDANCE SUPPORT HIGHER CHANCES FOR BELOW-NORMAL
TEMPERATURES ACROSS PORTIONS OF THE MID-ATLANTIC AND NORTHEAST. HIGH
PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES REMAIN FORECAST ACROSS ALASKA
UNDERNEATH ENHANCED SOUTHERLY FLOW. ABOVE-NORMAL TEMPERATURES ARE ALSO FORECAST
FOR HAWAII, SUPPORTED BY THE CONSOLIDATION REFORECAST TOOL.
THE DE-AMPLIFYING MID-LEVEL PATTERN ACROSS THE CONUS RESULTS IN DECREASING
SIGNALS FOR PRECIPITATION DURING WEEK-2. HOWEVER, INCREASED PACIFIC FLOW AND
POTENTIAL SHORTWAVE IMPULSES SUPPORT A BROAD AREA OF ENHANCED ABOVE-NORMAL
PRECIPITATION ACROSS MUCH OF THE WESTERN HALF OF THE CONUS, EXTENDING INTO THE
GREAT PLAINS AND UPPER MISSISSIPPI VALLEY. TROUGHING SHIFTING TOWARD THE
NORTHEAST PACIFIC MAY FURTHER ELEVATE PRECIPITATION CHANCES ACROSS THE PACIFIC
NORTHWEST BY THE END OF THE PERIOD. BELOW-NORMAL PRECIPITATION CHANCES REMAIN
ELEVATED ACROSS PARTS OF THE SOUTH-CENTRAL AND SOUTHEASTERN CONUS, ALTHOUGH
PROBABILITIES ARE REDUCED COMPARED TO THE 6-10 DAY PERIOD AS THE RIDGING
WEAKENS. NEAR-NORMAL PRECIPITATION IS FAVORED ACROSS THE NORTHEAST WHERE THERE
IS SOME POTENTIAL FOR ADDITIONAL SURFACE LOW PRESSURE DEVELOPMENT. INCREASED
CHANCES FOR ABOVE-NORMAL PRECIPITATION ARE FORECAST FOR MUCH OF ALASKA, WITH
THE HIGHEST PROBABILITIES (40 PERCENT) SHIFTING INTO THE SOUTHERN MAINLAND.
ABOVE-NORMAL PRECIPITATION IS FORECAST ACROSS HAWAII.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 6Z GFS
ENSEMBLE 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: AVERAGE, 3 OUT OF 5, DUE TO GOOD
MODEL AGREEMENT ON THE 500-HPA PATTERN EVOLUTION, OFFSET BY UNCERTAINTY
REGARDING A DE-AMPLIFYING FLOW PATTERN.
FORECASTER: THOMAS COLLOW
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON
OCTOBER 16.
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 15 - 19 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B B OREGON B A NRN CALIF B A
SRN CALIF B A IDAHO B A NEVADA B A
W MONTANA B A E MONTANA B A WYOMING A A
UTAH B A ARIZONA B A COLORADO A A
NEW MEXICO A A N DAKOTA A A S DAKOTA A A
NEBRASKA A A KANSAS A A OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA A A IOWA A A MISSOURI A B
ARKANSAS A B LOUISIANA A B WISCONSIN A A
ILLINOIS A N MISSISSIPPI A B MICHIGAN A N
INDIANA A B OHIO N B KENTUCKY A B
TENNESSEE A B ALABAMA A B NEW YORK B N
VERMONT N N NEW HAMP N A MAINE A A
MASS B A CONN B N RHODE IS B A
PENN B N NEW JERSEY B N W VIRGINIA N B
MARYLAND B N DELAWARE B N VIRGINIA B B
N CAROLINA B B S CAROLINA A B GEORGIA A B
FL PNHDL A B FL PENIN A B AK N SLOPE A 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 A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 17 - 23 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A N OREGON N A NRN CALIF B A
SRN CALIF B A IDAHO N A NEVADA B A
W MONTANA N A E MONTANA N A WYOMING A A
UTAH N 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 N W TEXAS A N
MINNESOTA A A IOWA A A MISSOURI A N
ARKANSAS A N LOUISIANA A B WISCONSIN A A
ILLINOIS A N MISSISSIPPI A B MICHIGAN N N
INDIANA A N OHIO N N KENTUCKY A N
TENNESSEE A B ALABAMA A B NEW YORK B N
VERMONT B N NEW HAMP B N MAINE A N
MASS B N CONN B N RHODE IS B N
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 A B GEORGIA A B
FL PNHDL A B FL PENIN A B AK N SLOPE A 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 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.
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