602
FXUS06 KWBC 011917
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE AUGUST 01 2023
6-10 DAY OUTLOOK FOR AUG 07 - 11 2023
THERE IS GOOD AGREEMENT ON THE PREDICTED 500-HPA CIRCULATION PATTERN OVER THE
FORECAST DOMAIN FOR THE 6-10 DAY PERIOD AMONG THE GFS, ECMWF AND CANADIAN
ENSEMBLE MEAN MODEL SOLUTIONS. THE MID-LEVEL HEIGHT BLEND DEPICTS A TROUGH AND
BELOW NORMAL 500-HPA HEIGHTS OVER MOST OF THE BERING SEA AND SOUTHWESTERN
ALASKA, AND A STRONG RIDGE AND POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE
REMAINDER OF ALASKA AND NORTHWESTERN CANADA. MAXIMUM POSITIVE MID-LEVEL HEIGHT
ANOMALIES EXCEED +210 METERS WELL NORTH OF UTQIAGVIK (BARROW), ALASKA, OVER THE
ARCTIC OCEAN. A ZONALLY ELONGATED MID-LEVEL TROUGH IS FORECAST OVER THE GULF OF
ALASKA WHICH EXTENDS AS FAR EAST AS THE BRITISH COLUMBIA AND U.S. PACIFIC
NORTHWEST COASTS. LOW-AMPLITUDE RIDGING IS INDICATED OVER THE WESTERN
CONTIGUOUS U.S. (CONUS) INTERIOR, WHICH CONNECTS TO A SUBTROPICAL RIDGE AND
NEAR TO ABOVE NORMAL 500-HPA HEIGHTS OVER THE SOUTHERN CONUS. A BROAD MID-LEVEL
TROUGH AND BELOW NORMAL 500-HPA HEIGHTS ARE DEPICTED OVER MUCH OF THE NORTHERN
AND CENTRAL CONUS EAST OF THE ROCKY MOUNTAINS.
ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS NEARLY ALL OF MAINLAND ALASKA,
SOUTHEAST ALASKA, INTERIOR PORTIONS OF THE WEST COAST STATES, THE SOUTHERN
CONUS FROM ARIZONA EASTWARD TO THE LOWER MISSISSIPPI VALLEY, TENNESSEE VALLEY,
THE SOUTHEAST, AND THE MID-ATLANTIC STATES. THIS IS ASSOCIATED WITH RIDGING
AND/OR NEAR TO ABOVE NORMAL MID-LEVEL HEIGHTS, AND IS CONSISTENT WITH
REFORECAST-CALIBRATED (AND TO A LESSER DEGREE, BIAS-CORRECTED) TEMPERATURE
TOOLS FROM THE 0Z GFS AND 0Z ECMWF ENSEMBLE MEAN MODEL RUNS. THE GREATEST
PROBABILITIES FOR ABOVE NORMAL TEMPERATURES (>70%) ARE INDICATED OVER SOUTHERN
TEXAS AND FLORIDA. BELOW NORMAL TEMPERATURE CHANCES ARE INCREASED OVER PARTS OF
THE ALEUTIANS, AND FROM THE NORTHERN AND CENTRAL ROCKIES EASTWARD ACROSS THE
NORTHERN AND CENTRAL PLAINS TO APPROXIMATELY THE UPPER HALF OF THE MISSISSIPPI
VALLEY AND THE GREAT LAKES REGION. THIS IS ASSOCIATED WITH MID-LEVEL TROUGHING
AND BELOW NORMAL 500-HPA HEIGHTS, AND IS ALSO SUPPORTED BY BIAS-CORRECTED AND
REFORECAST-CALIBRATED TEMPERATURE TOOLS.
TODAY’S 6-10 DAY PRECIPITATION OUTLOOK FAVORS A TILT IN THE ODDS TOWARDS ABOVE
NORMAL PRECIPITATION FOR PRACTICALLY ALL OF ALASKA SOUTH OF THE BROOKS RANGE,
ASSOCIATED WITH THE MID-LEVEL TROUGH OVER THE BERING SEA. BELOW NORMAL
PRECIPITATION IS SLIGHTLY FAVORED FOR PARTS OF THE NORTH SLOPE UNDER WELL ABOVE
NORMAL 500-HPA HEIGHTS AND INCREASED SUBSIDENCE ALOFT. MOIST FLOW AHEAD OF THE
TROUGH PREDICTED OVER THE GULF OF ALASKA AND NORTHEAST PACIFIC ENHANCES THE
ODDS FOR ABOVE NORMAL PRECIPITATION FOR APPROXIMATELY THE NORTHWESTERN QUARTER
OF THE CONUS, AND MOST OF THE GREAT PLAINS REGION. MOST AREAS EAST OF THE
PLAINS ARE SLIGHTLY FAVORED TO GET ABOVE NORMAL PRECIPITATION DURING THE
FORECAST PERIOD AND ENHANCED PROBABILITIES FOR ABOVE NORMAL PRECIPITATION
EXCEED 40% ACROSS THE SOUTH-CENTRAL PLAINS, SOUTH-CENTRAL MISSISSIPPI VALLEY TO
THE TENNESSEE VALLEY, GENERALLY OUTLINING THE 500-HPA RIDGE-TROUGH PATTERN
ANTICIPATED ACROSS THE CONUS. THIS AREA IS ALSO WHERE A BAROCLINIC ZONE IS
EXPECTED TO STALL, WITH INCREASED GULF INFLOW FROM THE SOUTH. INDIVIDUAL
DISTURBANCES MOVING ACROSS PARTS OF THE NORTHEAST RESULT IN A >40% CHANCE OF
ABOVE NORMAL PRECIPITATION FOR THIS AREA. BELOW NORMAL PRECIPITATION CHANCES
ARE INCREASED FOR NEVADA, FAR SOUTHEASTERN PARTS OF CALIFORNIA, MOST OF THE
FOUR CORNERS STATES, AND SOUTHERN TEXAS, AS INDICATED BY THE CONSOLIDATION
PRECIPITATION TOOL, AND ASSOCIATED WITH A WEAKENED AND SOUTHWARD-SHIFTED
MONSOON RIDGE.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
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: ABOVE AVERAGE, 4 OUT OF 5, BASED
ON GOOD AGREEMENT AMONG THE DYNAMICAL MODEL 500-HPA HEIGHT FORECASTS AND MOST
SURFACE TEMPERATURE TOOLS, OFFSET BY SOME AREAS OF DISAGREEMENT AMONG
PRECIPITATION TOOLS.
8-14 DAY OUTLOOK FOR AUG 09 - 15 2023
ENSEMBLE MEAN SOLUTIONS FOR THE WEEK-2 500-HPA HEIGHT FORECAST ARE GENERALLY IN
GOOD AGREEMENT TODAY OVER THE FORECAST DOMAIN. A SIGNIFICANT DEEPENING OF THE
BERING SEA TROUGH IS ANTICIPATED BY THE ENSEMBLE MEAN MODEL SOLUTIONS, WITH
MID-LEVEL HEIGHTS FALLING TO NEARLY 100 METERS BELOW NORMAL OVER THE ALEUTIANS.
A STRONG ANOMALOUS RIDGE IS INDICATED OVER NORTHERN AND EASTERN ALASKA AND
NORTHWESTERN CANADA, WITH MAXIMUM MID-LEVEL HEIGHT ANOMALIES OF +150 METERS OR
MORE ABOVE NORMAL OVER THE ARCTIC OCEAN WELL NORTH OF UTQIAGVIK (BARROW). A
TROUGH ACCOMPANIED BY NEAR NORMAL 500-HPA HEIGHTS IS DEPICTED OVER EASTERN
PORTIONS OF NORTH AMERICA. SUBTROPICAL RIDGING AND NEAR TO SLIGHTLY ABOVE
NORMAL MID-LEVEL HEIGHTS ARE PREDICTED ACROSS THE SOUTHERN CONUS, WITH THE
ELONGATED MEAN RIDGE AXIS NEAR THE 30TH PARALLEL. THE POSITION OF THIS AXIS IS
NOT CONDUCIVE FOR THE NORTHWARD TRANSPORT OF MONSOONAL MOISTURE ACROSS THE
MEXICAN BORDER INTO ARIZONA AND NEW MEXICO. A SLIGHTLY MORE AMPLIFIED TROUGH IS
FORECAST NEAR THE WEST COAST OF THE CONUS, RELATIVE TO THE EARLIER 6-10 DAY
PERIOD.
REFORECAST-CALIBRATED TEMPERATURE TOOLS FAVOR ABOVE NORMAL TEMPERATURES OVER
MOST OF MAINLAND AND SOUTHEAST ALASKA IN THE WEEK-2 PERIOD, UNDER MOSTLY
RIDGING AND/OR POSITIVE 500-HPA HEIGHT ANOMALIES. BELOW NORMAL TEMPERATURE
CHANCES ARE INCREASED OVER THE ALEUTIANS AND ALASKA PENINSULA, IN PROXIMITY TO
A DEEPENING MID-LEVEL TROUGH. FOR THE CONUS, ABOVE NORMAL TEMPERATURE CHANCES
ARE INCREASED OVER INTERIOR SECTIONS OF WASHINGTON AND OREGON, AND NEVADA,
AHEAD OF A WEAK TROUGH AXIS. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED FROM
THE FOUR CORNERS REGION EASTWARD ACROSS THE SOUTHERN PLAINS, LOWER MISSISSIPPI
VALLEY, TENNESSEE VALLEY, THE CENTRAL AND SOUTHERN APPALACHIANS, SOUTHEAST, AND
MID-ATLANTIC REGION. MAXIMUM PROBABILITIES FOR ABOVE NORMAL TEMPERATURES EXCEED
70% OVER THE FLORIDA PENINSULA. THIS IS SUPPORTED BY REFORECAST-CALIBRATED
TEMPERATURES FROM THE ECMWF ENSEMBLE MEAN MODEL, WHICH REPRESENTS A REASONABLE
COMPROMISE BETWEEN THE WARMER GEFS SOLUTION AND COOLER CANADIAN ENSEMBLE MEAN
SOLUTION. BELOW NORMAL TEMPERATURES ARE FAVORED FROM THE NORTHERN AND CENTRAL
ROCKIES EASTWARD ACROSS THE NORTHERN AND CENTRAL PLAINS TO THE UPPER
MISSISSIPPI VALLEY AND THE GREAT LAKES REGION, ASSOCIATED WITH A MID-LEVEL
TROUGH.
THE WEEK-2 PRECIPITATION OUTLOOK IS SIMILAR TO THE 6-10 DAY PRECIPITATION
OUTLOOK, THOUGH WITH SOME ADJUSTMENTS. THERE ARE INCREASED CHANCES FOR ABOVE
NORMAL PRECIPITATION FOR THE NORTHWESTERN QUARTER OF THE CONUS, MOST OF THE
GREAT PLAINS AND MISSISSIPPI VALLEY, AND CONTINUING EASTWARD TO THE ATLANTIC
COAST FROM MAINE TO VIRGINIA, AS WELL AS INTERIOR PORTIONS OF THE SOUTHEAST AND
CENTRAL GULF COAST REGION. THE REASONING FOR THIS IS SIMILAR TO THAT DESCRIBED
ABOVE IN THE 6-10 DAY PRECIPITATION SECTION. BELOW NORMAL PRECIPITATION CHANCES
ARE ELEVATED OVER MUCH OF THE FOUR CORNERS REGION, SOUTHEASTERN NEVADA, AND
ADJACENT PARTS OF EXTREME SOUTHEASTERN CALIFORNIA, SUPPORTED BY THE
CONSOLIDATION PRECIPITATION TOOL, AND CONSISTENT WITH A WEAKENED AND
SOUTHWARD-SHIFTED MONSOON. ABOVE NORMAL PRECIPITATION IS FAVORED FOR MOST OF
ALASKA SOUTH OF THE BROOKS RANGE IN A WIDESPREAD ONSHORE FLOW REGIME AHEAD OF A
DEEP ALEUTIAN TROUGH. A SMALL AREA OF SLIGHTLY FAVORED BELOW NORMAL
PRECIPITATION IS INDICATED OVER PART OF THE NORTH SLOPE REGION.
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: NEAR AVERAGE, 3 OUT OF 5, BASED ON
GOOD AGREEMENT AMONG THE DYNAMICAL MODEL 500-HPA HEIGHT AND SURFACE TEMPERATURE
FORECASTS, OFFSET BY FORECASTS OF WEAK 500-HPA HEIGHT ANOMALIES AND WEAK
SIGNALS IN THE PRECIPITATION TOOLS.
FORECASTER: ANTHONY A
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 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:
19940813 - 19570815 - 19540808 - 19970727 - 19610729
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:
19940813 - 19570813 - 20040806 - 19540808 - 19630813
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 07 - 11 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF N N
SRN CALIF N N IDAHO B A NEVADA A B
W MONTANA B A E MONTANA B A WYOMING B A
UTAH N B ARIZONA A B COLORADO B N
NEW MEXICO A B N DAKOTA B A S DAKOTA B A
NEBRASKA B A KANSAS B A OKLAHOMA N A
N TEXAS A A S TEXAS A N W TEXAS A A
MINNESOTA B A IOWA B A MISSOURI N A
ARKANSAS A A LOUISIANA A A WISCONSIN B N
ILLINOIS N A MISSISSIPPI A A MICHIGAN B A
INDIANA N A OHIO N A KENTUCKY N A
TENNESSEE A A ALABAMA A A NEW YORK N A
VERMONT B A NEW HAMP N A MAINE N A
MASS N A CONN N A RHODE IS N A
PENN N A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A N VIRGINIA A N
N CAROLINA A N S CAROLINA A N GEORGIA A A
FL PNHDL A N FL PENIN A N AK N SLOPE A N
AK ALEUTIAN N 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 AUG 09 - 15 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF N N
SRN CALIF N N IDAHO B A NEVADA A N
W MONTANA B A E MONTANA B A WYOMING B A
UTAH N N ARIZONA A N COLORADO B N
NEW MEXICO A N N DAKOTA B A S DAKOTA B A
NEBRASKA B A KANSAS N A OKLAHOMA A A
N TEXAS A A S TEXAS A N W TEXAS A N
MINNESOTA B A IOWA B A MISSOURI N A
ARKANSAS A A LOUISIANA A N WISCONSIN B A
ILLINOIS N A MISSISSIPPI A A MICHIGAN B A
INDIANA N A OHIO N A KENTUCKY N A
TENNESSEE A A ALABAMA A A NEW YORK N A
VERMONT B A NEW HAMP N A MAINE N A
MASS N A CONN N A RHODE IS N A
PENN N A NEW JERSEY N A W VIRGINIA N A
MARYLAND A A DELAWARE A A VIRGINIA A A
N CAROLINA A A S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A N AK N SLOPE A N
AK ALEUTIAN B 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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