552
FXUS06 KWBC 032007
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU SEPTEMBER 03 2026
6-10 DAY OUTLOOK FOR SEP 09 - 13 2026
TODAY'S NUMERICAL MODELS PREDICT A COMPLEX 500-HPA FLOW PATTERN, ESPECIALLY
ACROSS THE WESTERN CONTIGUOUS UNITED STATES (CONUS). THE TROPICAL EASTERN AND
CENTRAL NORTH PACIFIC REMAINS ACTIVE, WITH THREE HURRICANES CURRENTLY SCATTERED
ACROSS THE REGION (CATEGORY-4 LOWELL, CATEGORY-3 KARINA, CATEGORY-1 MARIE) AND
ELEVATED CHANCES FOR AT LEAST ONE ADDITIONAL SYSTEM TO FORM DURING THE 6-10 OR
8-14 DAY PERIOD. MEANWHILE, A MID-LEVEL TROUGH IS FORECAST NEAR THE WEST COAST,
WHICH MAY HELP ADVECT SOME OF THIS TROPICAL MOISTURE INTO THE WESTERN CONUS.
DOWNSTREAM, EXPANSIVE RIDGING IS FORECAST ACROSS MUCH OF THE CENTRAL AND
SOUTHEASTERN CONUS. MODELS GENERALLY AGREE ON THIS MEAN PATTERN, BUT
UNCERTAINTY REMAINS REGARDING THE PLACEMENT OF THE RIDGE AXIS AND THE AREA OF
GREATEST POSITIVE 500-HPA ANOMALIES. THE GEFS AND GEFS-AI SHOW A LOCATION
SIMILAR TO YESTERDAY OVER THE INTERIOR EASTERN CONUS, BUT WITH SIGNIFICANT
POSITIVE MEAN 500-HPA HEIGHT ANOMALIES STRETCHING FARTHER NORTH THROUGH THE
LOWER OHIO VALLEY AND GREAT LAKES. MEANWHILE, THE EUROPEAN ENSEMBLE (ECENS)
MEAN POSITIONS THE RIDGE AXIS FARTHER WEST TOWARD THE CENTRAL CONUS, WHICH IS A
WESTWARD SHIFT FROM YESTERDAY. THE CANADIAN ENSEMBLE (CMCE) MEAN, WHICH WAS A
LITTLE FARTHER WEST THAN THE OTHER ENSEMBLE MEANS YESTERDAY, HAS SHIFTED TO THE
EAST TODAY, LOOKING LIKE A COMPROMISE BETWEEN THE GEFS AND ECENS MEANS. GIVEN
THE UNCERTAINTY, THE OFFICIAL FORECAST IS A COMPROMISE OF THESE SOLUTIONS
LEANING MORE TOWARD THE GEFS, WHICH IS MORE CONSISTENT WITH ITS EARLIER RUNS.
DOWNSTREAM, THE ENSEMBLE MEANS CONTINUE TO SHOW A PERSISTENT 500-HPA TROUGH
OVER OR NEAR THE CANADIAN MARITIMES, WITH AN AXIS STRETCHING SOUTHWARD ALONG AT
LEAST PART OF THE EASTERN SEABOARD. MODELS REMAIN IN GOOD AGREEMENT ON THIS
GENERALIZED MEAN PATTERN, BUT DIVERGE REGARDING THE SOUTHWARD EXTENT OF ITS
INFLUENCE ALONG THE EAST COAST. FARTHER NORTH, A SHARP 500-HPA HEIGHT GRADIENT
IS FORECAST ACROSS ALASKA, RESULTING IN AN ACTIVE PATTERN. ANOMALOUS RIDGING IS
EXPECTED ACROSS THE ALEUTIANS AND ADJACENT NORTH PACIFIC, WHERE MEAN 500-HPA
HEIGHT ANOMALIES REACH +12 DM IN THE MANUAL BLEND. AT THE SAME TIME, AN
ANOMALOUS TROUGH IS EXPECTED ACROSS EASTERN SIBERIA AND THE BERING STRAIT,
LEAVING 500-HPA HEIGHTS NEAR OR SLIGHTLY BELOW NORMAL ACROSS MAINLAND ALASKA.
AN ACTIVE PATTERN IS ALSO POSSIBLE ACROSS HAWAII DUE TO ELEVATED TROPICAL
ACTIVITY IN THE EASTERN AND CENTRAL NORTH PACIFIC. PLEASE REFER TO THE NATIONAL
HURRICANE CENTER FOR THE LATEST INFORMATION ON TROPICAL CONDITIONS.
THE MID-LEVEL RIDGING EXPECTED ACROSS MUCH OF THE CONUS FAVORS ABOVE NORMAL
TEMPERATURES FROM THE DESERT SOUTHWEST AND ROCKIES EASTWARD THROUGH MOST OF THE
ATLANTIC COAST. CHANCES FOR ABOVE-NORMAL TEMPERATURES EXCEED 70 PERCENT FROM
THE CENTRAL AND SOUTHERN GREAT PLAINS THROUGH THE GULF COAST REGION.
TEMPERATURES ARE EXPECTED TO AVERAGE CLOSER TO NORMAL ACROSS MOST OF THE
PACIFIC COAST STATES, THE NORTHERN INTERMOUNTAIN WEST, AND MUCH OF NEW ENGLAND
DUE TO MID-LEVEL TROUGHING ENCROACHING ON THOSE AREAS. THERE ARE SLIGHTLY
ELEVATED CHANCES FOR WARMER THAN NORMAL CONDITIONS THROUGH NORTHERN, CENTRAL,
AND EASTERN ALASKA, WITH ODDS TOPPING 40 PERCENT IN THE SOUTHEASTERN MAINLAND
AND ADJACENT PANHANDLE. HAWAII IS LIKELY TO BE WARMER THAN NORMAL, PRIMARILY
DUE TO THE LARGE RESERVOIR OF ABOVE-NORMAL SEA SURFACE TEMPERATURES (SSTS) IN
THE ADJACENT PACIFIC, DRIVEN IN PART BY THE STRONG CURRENT EL NINO. CHANCES FOR
WARMTH INCREASE FROM NORTHWEST TO SOUTHEAST ACROSS THE ISLAND CHAIN, EXCEEDING
70 PERCENT IN SOUTHERN SECTIONS OF THE BIG ISLAND.
ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS MOST OF THE WEST, TIED TO
PERSISTENT CYCLONIC MID-LATITUDE FLOW COUPLED WITH THE POTENTIAL ADVECTION OF
TROPICAL MOISTURE FROM AN ACTIVE EASTERN TROPICAL PACIFIC. CONFIDENCE FOR
ABOVE-NORMAL PRECIPITATION IS HIGHEST (ABOVE 50 PERCENT CHANCE) ACROSS PARTS OF
THE SOUTHWEST (WHERE TROPICAL MOISTURE INFLUX IS MOST LIKELY) AND PARTS OF THE
NORTHWEST (DUE TO PROXIMITY OF THE MID-LEVEL TROUGH). ELEVATED CHANCES OF
ABOVE-NORMAL PRECIPITATION EXTEND EASTWARD THROUGH THE ROCKIES AND ACROSS THE
NORTHERN TIER OF THE CONUS. ALONG THE PERIPHERY OF THE ANTICIPATED MID-LEVEL
RIDGE. THERE IS A LOT OF UNCERTAINTY FROM THE CENTRAL GREAT PLAINS SOUTHWARD
ACROSS THE GULF COAST REGION AND EASTWARD THROUGH MOST OF THE ATLANTIC
SEABOARD. ALMOST ALL RAW AND REFORECAST MODEL OUTPUT GENERALLY FAVOR
ABOVE-NORMAL PRECIPITATION OVER THIS BROAD REGION WHILE ANALOGS AND
TELECONNECTIONS SHOW BELOW-NORMAL PRECIPITATION MOST LIKELY. GIVEN THIS
DISCREPANCY, THE OFFICIAL FORECAST FAVORS NEITHER ABNORMALLY DRY NOR ABNORMALLY
WET CONDITIONS OVER THIS BROAD AREA. MEANWHILE, THE ENHANCED MID-LEVEL HEIGHT
GRADIENT SUPPORTS INCREASED MOISTURE ADVECTION ACROSS, LEADING TO ELEVATED
PROBABILITIES OF ABOVE-NORMAL PRECIPITATION FOR MOST OF THE STATE. ABOVE-NORMAL
PRECIPITATION IS FAVORED ACROSS HAWAII, CONSISTENT WITH MOST GUIDANCE AND
ENHANCED BY THE ACTIVE EASTERN AND CENTRAL TROPICAL PACIFIC. ODDS FOR SURPLUS
PRECIPITATION EXCEED 50 PERCENT STATEWIDE.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 15% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 30% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED
ON DAY 8, 20% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF
TODAY'S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND 25% OF TODAY'S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: BELOW AVERAGE, 2 OUT OF 5, DUE TO
A PREDICTED COMPLEX 500-HPA FLOW PATTERN, THE INHERENT UNCERTAINTY OF TROPICAL
CONDITIONS, AND THE SHARP DIFFERENCES BETWEEN MODEL-DERIVED PRECIPITATION
FORECASTS COMPARED TO ANALOG AND TELECONNECTION SIGNALS.
8-14 DAY OUTLOOK FOR SEP 11 - 17 2026
THE GENERAL PATTERN OF MID-LEVEL FEATURES IS EXPECTED TO CONTINUE DURING THE
WEEK-2 PERIOD, ALTHOUGH SOME SLOW DEAMPLIFICATION IS POSSIBLE. THE ACTIVE
EASTERN AND CENTRAL TROPICAL PACIFIC AND WEAK MID-LEVEL TROUGHING ALONG MUCH OF
THE WEST COAST FAVORS A CONTINUING INFLUX OF TROPICAL MOISTURE THERE, BUT
UNCERTAINTY IS HIGH REGARDING THE EVOLUTION OF CONDITIONS IN THE TROPICAL
PACIFIC AND ITS POTENTIAL TO INCREASE THE AMOUNT OF TROPICAL MOISTURE BEING
PULLED INTO THE WESTERN CONUS. EXPANSIVE RIDGING IS FORECAST ACROSS MUCH OF THE
CENTRAL AND EASTERN CONUS, RESULTING IN A BROAD AREA OF MODESTLY ABOVE-NORMAL
MID-LEVEL HEIGHTS, ALTHOUGH MODELS REMAIN IN MEDIOCRE AGREEMENT ON THE
PLACEMENT AND STRENGTH OF THE GREATEST 500-HPA HEIGHT ANOMALIES. AGAIN, THE
OFFICIAL FORECAST IS A COMPROMISE LEANING TOWARD THE FARTHER-EAST AND MORE
CONSISTENT GEFS MEAN, BUT THE CONTINUING DIFFERENCES OF LOCATION AND EXTENT
LOWER CONFIDENCE. MID-LEVEL TROUGHING IS EXPECTED TO PERSIST OVER ATLANTIC
CANADA, FAVORING SLIGHTLY BELOW-NORMAL HEIGHTS ACROSS NORTHERN PARTS OF THE
EASTERN SEABOARD, WITH MORE UNCERTAINTY FARTHER SOUTH. THE ENHANCED HEIGHT
GRADIENT ACROSS ALASKA IS EXPECTED TO REMAIN IN PLACE, BUT SLOWLY WEAKEN WITH
TIME DUE TO EXPECTED WEAKENING OF THE MID-LEVEL RIDGING IN THE NORTH PACIFIC.
SUBNORMAL MEAN 500-HPA HEIGHTS ARE ANTICIPATED STATEWIDE DURING WEEK-2,
ESPECIALLY IN NORTHWESTERN SECTIONS. UNCERTAINTY IS HIGH ACROSS HAWAII. THE
EASTERN AND CENTRAL TROPICAL PACIFIC ARE LIKELY TO REMAIN ACTIVE, BUT THE
SENSIBLE WEATHER ACROSS THE STATE WILL DEPEND ON THE EVOLUTION OF INDIVIDUAL
TROPICAL SYSTEMS AND THEIR MOISTURE CONTENT.
ABOVE-NORMAL TEMPERATURES ARE LIKELY TO PERSIST ACROSS A LARGE PORTION OF THE
CONUS DURING WEEK-2, UNDER GENERALLY ABOVE-NORMAL 500-HPA HEIGHTS. CONFIDENCE
REMAINS PARTICULARLY HIGH (OVER 70 PERCENT CHANCE) FROM THE SOUTHEASTERN GREAT
PLAINS EASTWARD INTO THE SOUTH ATLANTIC REGION. CLOSER TO MID-LEVEL TROUGHING,
CONFIDENCE IN ABOVE-NORMAL TEMPERATURES IS LOWER FARTHER NORTH ALONG THE
ATLANTIC COAST WHILE NEAR-NORMAL TEMPERATURES ARE FAVORED ALONG THE WESTERN
TIER OF THE CONUS. LOWERING 500-HPA HEIGHTS SLIGHTLY FAVOR SUBNORMAL
TEMPERATURES ACROSS SOUTHWESTERN ALASKA WHILE SLIGHTLY INCREASED ODDS FOR
WARMTH CONTINUE ACROSS THE SOUTHERN AND EASTERN TIERS OF THE MAINLAND.
ABOVE-NORMAL TEMPERATURES REMAIN LIKELY ACROSS HAWAII, CONSISTENT WITH
CONTINUED ABOVE-NORMAL SSTS ACROSS THE EASTERN AND CENTRAL TROPICAL PACIFIC.
MID-LEVEL TROUGHING COMBINED WITH INCREASED ACTIVITY IN THE EASTERN TROPICAL
PACIFIC SUPPORT A CONTINUED ACTIVE PATTERN ACROSS MUCH OF THE WEST, WITH
PROBABILITIES OF ABOVE-NORMAL PRECIPITATION EXCEEDING 40 PERCENT FROM THE
PACIFIC COAST INTO THE WESTERN ROCKIES. DOWNSTREAM, ABOVE-NORMAL PRECIPITATION
IS MARGINALLY FAVORED OVER MOST OF THE ROCKIES AND PLAINS AS WELL AS THE
NORTHERN TIER OF THE CONUS ON THE PERIPHERY OF MID-LEVEL RIDGING. THERE IS
CONSIDERABLE UNCERTAINTY OVER THE REMAINDER OF THE CONUS WITH RAW AND
STATISTICALLY-DERIVED ENSEMBLE OUTPUT CONTINUING TO FAVOR ABOVE-NORMAL
PRECIPITATION WHILE ANALOGS AND TELECONNECTIONS FAVOR DRIER THAN NORMAL
CONDITIONS JUST AS STRONGLY. ABOVE-NORMAL PRECIPITATION IS FAVORED FOR MOST OF
ALASKA DUE TO THE PREDICTED TROUGHING ALONG WITH A FAIRLY ROBUST 500-HPA HEIGHT
ANOMALY GRADIENT. THE ACTIVE PATTERN ACROSS THE EASTERN AND CENTRAL TROPICAL
PACIFIC SUPPORTS THE CONTINUATION OF INCREASED CHANCES OF ABOVE-NORMAL
PRECIPITATION ACROSS HAWAII.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 17% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 35% OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED
ON DAY 11, 23% 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
UNCERTAINTY IN THE TROPICS, THE PREDICTED COMPLEX MID-LEVEL LOW PATTERN IN THE
WESTERN CONUS, AND LARGE DIFFERENCES OVER MUCH OF THE CENTRAL AND EASTERN CONUS
BETWEEN THE WET-LEANING MODEL-DERIVED PRECIPITATION FORECASTS AND THE MUCH
DRIER ANALOGS AND TELECONNECTIONS.
FORECASTER: RICH TINKER
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:
20190916 - 20050904 - 20240822 - 20240912 - 20050828
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:
20050905 - 20240822 - 20240912 - 20050831 - 20190916
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 09 - 13 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON N A NRN CALIF N A
SRN CALIF A A IDAHO N A NEVADA N A
W MONTANA N 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 N OKLAHOMA A N
N TEXAS A N S TEXAS A N W TEXAS A A
MINNESOTA A A 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 N NEW YORK A N
VERMONT A A NEW HAMP N A MAINE N A
MASS N A CONN A N RHODE IS N N
PENN A N NEW JERSEY A N W VIRGINIA A N
MARYLAND A N DELAWARE A N VIRGINIA A N
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A N AK N SLOPE A A
AK ALEUTIAN N N AK WESTERN N A AK INT BSN A A
AK S INT A A AK SO COAST A N AK PNHDL A A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 11 - 17 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON N A NRN CALIF N 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 N W TEXAS A A
MINNESOTA A A 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 N NEW YORK A N
VERMONT A N NEW HAMP A N MAINE A N
MASS A N CONN A N RHODE IS A N
PENN A N NEW JERSEY A N W VIRGINIA A N
MARYLAND A N DELAWARE A N VIRGINIA A N
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A N AK N SLOPE A A
AK ALEUTIAN N N AK WESTERN B A AK INT BSN N A
AK S INT N A AK SO COAST N A AK PNHDL N 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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page