670
FXUS06 KWBC 111915
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON AUGUST 11 2025
6-10 DAY OUTLOOK FOR AUG 17 - 21 2025
TODAY'S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 500-HPA
CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS DURING THE
6-10 DAY PERIOD. THE MANUAL 500-HPA HEIGHT BLEND IS BASED PRIMARILY ON THE
ENSEMBLE MEANS FROM THE GEFS, ECMWF AND CANADIAN MODELS. THE RESULTANT MANUAL
BLEND FEATURES AMPLIFIED RIDGING OVER THE BERING SEA AND MODERATE TROUGHING
DOWNSTREAM OVER THE NORTH PACIFIC, BROAD RIDGING OVER THE CONTIGUOUS U.S.
(CONUS) AND TROUGHING OVER QUEBEC, EXTENDING INTO THE NORTH ATLANTIC.
EXPANSIVE POSITIVE 500-HPA HEIGHT ANOMALIES OVER MUCH OF NORTH AMERICA BROADLY
FAVORS ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE CONUS, WITH PROBABILITIES OF
AT LEAST 50% ALMOST UNIVERSAL FROM THE GREAT BASIN TO THE APPALACHIANS, ALONG
WITH THE GULF COAST. CHANCES OF ABOVE-NORMAL TEMPERATURES WEAKEN ALONG THE WEST
COAST AND FOR THE NORTHEAST, WITH NEAR-NORMAL TEMPERATURES MOST LIKELY FOR
PORTIONS OF NORTHERN NEW ENGLAND, CALIFORNIA, AND WASHINGTON STATE. AMPLIFIED
RIDGING OVER THE BERING SEA TILTS THE ODDS TOWARDS ABOVE-NORMAL TEMPERATURES
FOR SOUTHERN AND SOUTHEASTERN ALASKA, WHILE AMPLIFIED TROUGHING UPSTREAM OVER
THE CHUKCHI SEA FAVORS BELOW-NORMAL TEMPERATURES FOR THE NORTH SLOPE. CONTINUED
POSITIVE SEA SURFACE TEMPERATURES NEAR HAWAII FAVOR PERSISTENT ABOVE-NORMAL
TEMPERATURES FOR THE STATE.
TROUGHING OVER THE NORTH PACIFIC FAVORS ABOVE-NORMAL PRECIPITATION FOR THE
NORTHWESTERN CONUS AND ALONG THE U.S.-CANADA BORDER, AND MONSOON ACTIVITY ALSO
TILTS THE ODDS TOWARDS ABOVE-NORMAL PRECIPITATION FOR PORTIONS OF THE DESERT
SOUTHWEST AND ROCKIES. THESE TWIN STREAMS OF MOISTURE CONVERGE OVER THE PLAINS,
RESULTING IN ENHANCED ATMOSPHERIC MOISTURE DOWNSTREAM AND TILTING THE MIDDLE
AND UPPER MISSISSIPPI, TENNESSEE, AND OHIO VALLEYS AS WELL AS THE APPALACHIANS
TOWARDS ABOVE-NORMAL PRECIPITATION. PORTIONS OF THE MID-ATLANTIC AND NORTHEAST
U.S. ALSO ARE SLIGHTLY FAVORED FOR ABOVE-NORMAL PRECIPITATION, WHICH MAY COME
UNDER THE INFLUENCE OF A TROPICAL CYCLONE (TC) THAT JUST FORMED JUST WEST OF
THE CAPE VERDE ISLANDS EARLIER TODAY. MODEL GUIDANCE INDICATES POOR PENETRATION
OF MONSOONAL MOISTURE INTO THE GREAT BASIN, RESULTING IN BELOW-NORMAL
PRECIPITATION FOR THE REGION. IN ALASKA, TROUGHING OVER THE CHUKCHI SEA FAVORS
ABOVE-NORMAL PRECIPITATION FOR MUCH OF THE ALASKAN MAINLAND, HOWEVER RIDGING
OVER THE BERING SEA PREVENTS SOUTHWARD SPREAD OF THIS ENHANCED MOISTURE,
TILTING THE SOUTHERN COAST TOWARDS BELOW-NORMAL PRECIPITATION.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 20% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 40% 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. VERY
GOOD AGREEMENT AMONG THE TEMPERATURE AND PRECIPITATION DYNAMICAL AND
STATISTICAL TOOLS IS OFFSET BY DIVERGING MODEL SOLUTIONS LATE IN THE PERIOD.
8-14 DAY OUTLOOK FOR AUG 19 - 25 2025
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD PREDICT A VERY SIMILAR PATTERN
TO THE 6-10DAY PERIOD. STRONG RIDGING REMAINS IN PLACE OVER THE BERING SEA AND
OVER THE SOUTHWESTERN CONUS. TROUGHING FEATURES OVER BOTH THE NORTH PACIFIC AND
CHUKCHI SEA ARE FAVORED TO WEAKEN BUT REMAIN, WHILE MODEL ENSEMBLES DEPICT THE
TROUGH OVER QUEBEC RETROGRADING AND DEEPENING SLIGHTLY, RESULTING IN A
NOTICEABLE SHIFT IN TEMPERATURES FOR MUCH OF THE EASTERN CONUS.
WITH THIS DEEPENING AND RETROGRADING TROUGH, THE NORTHEASTERN CONUS IS FAVORED
TO SHIFT FROM ABOVE-NORMAL TEMPERATURES DURING THE 6-10 DAY PERIOD TO
NEAR-NORMAL FOR WEEK-2, WITH A SLIGHT TILT TOWARDS BELOW-NORMAL TEMPERATURES
INDICATED FOR NEW ENGLAND. ABOVE-NORMAL TEMPERATURES CONTINUE TO BE FAVORED
ACROSS THE WESTERN HALF OF THE LOWER 48 AND ALONG THE GULF COAST, ALTHOUGH
PROBABILITIES ARE SUBSTANTIALLY LOWER FOR THE GREAT PLAINS AND SOUTHEAST U.S.
FOR ALASKA THE PERSISTENT UPPER-LEVEL PATTERN RESULTS IN A MOSTLY PERSISTENCE
FORECAST, ALTHOUGH WEAKENING TROUGHING OVER THE CHUKCHI SEA ALLOWS FOR A SLIGHT
SHIFT NORTHWARD FOR ABOVE-NORMAL TEMPERATURES. SIMILARLY, THE HAWAII FORECAST
IS LITTLE CHANGED FROM THE 6-10 DAY PERIOD WITH NO CHANGES IN TEMPERATURE
FORCING IN THE REGION.
MONSOON MOISTURE IS FAVORED TO CONTINUE SPREADING INTO THE SOUTHWESTERN CONUS,
TILTING THE ODDS TOWARDS ABOVE-NORMAL PRECIPITATION FROM THE DESERT SOUTHWEST
UP INTO THE CENTRAL ROCKIES. MODELS DEPICT PACIFIC MOISTURE MOVING OVER THE TOP
OF THE CONUS RIDGE AND ALONG THE U.S.-CANADA BORDER, SLIGHTLY FAVORING
ABOVE-NORMAL PRECIPITATION FOR PORTIONS OF THE NORTHERN PLAINS AS WELL.
TROPICAL MOISTURE COULD ALSO PLAY A ROLE IN THE WEEK-2 PRECIPITATION OUTLOOK AS
THE ATLANTIC TC SEASON PICKS UP, RESULTING IN A MODEST TILT TOWARDS
ABOVE-NORMAL PRECIPITATION FOR THE GULF COAST AND UP THE EAST COAST. AS THE
WEEK PROGRESSES THE TROPICS WILL BE CLOSELY MONITORED FOR POTENTIAL IMPACTS
FROM ANY TCS. THE FAVORED WETNESS FOR THE EASTERN CONUS IS ALSO CONSISTENT WITH
AN AMPLIFYING 500-HPA TROUGH.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 34% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 33% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5. GOOD
AGREEMENT AMONG THE TEMPERATURE AND PRECIPITATION DYNAMICAL AND STATISTICAL
TOOLS IS OFFSET BY A SIGNIFICANT PATTERN SHIFT INDICATED DURING WEEK-2.
FORECASTER: DANIEL BARANDIARAN
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:
20090817 - 19880801 - 19900727 - 20020726 - 20020810
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:
19880731 - 20020811 - 20090816 - 19900729 - 20040728
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 17 - 21 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON A A NRN CALIF A N
SRN CALIF N N IDAHO A N NEVADA A B
W MONTANA A A E MONTANA A A WYOMING A N
UTAH A B ARIZONA A N 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 A MISSOURI A A
ARKANSAS A N LOUISIANA A N WISCONSIN A A
ILLINOIS A A MISSISSIPPI A N MICHIGAN A N
INDIANA A A OHIO A N KENTUCKY A A
TENNESSEE A A ALABAMA A N NEW YORK A N
VERMONT N A NEW HAMP N A MAINE N A
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 N
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A N AK N SLOPE B A
AK ALEUTIAN A B AK WESTERN N A AK INT BSN N A
AK S INT A B AK SO COAST A B AK PNHDL A N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 19 - 25 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A N
SRN CALIF A N IDAHO A N NEVADA A N
W MONTANA A N E MONTANA A N WYOMING A N
UTAH A N ARIZONA A A COLORADO A N
NEW MEXICO A N N DAKOTA A N S DAKOTA A N
NEBRASKA A N KANSAS A N OKLAHOMA A N
N TEXAS A N S TEXAS A A W TEXAS A N
MINNESOTA A N IOWA N N MISSOURI A N
ARKANSAS A N LOUISIANA A A WISCONSIN N N
ILLINOIS N B MISSISSIPPI A N MICHIGAN N B
INDIANA N B OHIO N N KENTUCKY N N
TENNESSEE N N ALABAMA A A NEW YORK N N
VERMONT B N NEW HAMP B N MAINE B N
MASS B N CONN N N RHODE IS B A
PENN N N NEW JERSEY N A W VIRGINIA N N
MARYLAND N A DELAWARE N A VIRGINIA N A
N CAROLINA N A S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN A A AK N SLOPE B A
AK ALEUTIAN A B AK WESTERN N A AK INT BSN N A
AK S INT A N AK SO COAST A N AK PNHDL A 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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