452
FXUS06 KWBC 311937
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON JULY 31 2023
6-10 DAY OUTLOOK FOR AUG 06 - 10 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
NEAR TO 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 WESTERN CANADA. MAXIMUM POSITIVE MID-LEVEL
HEIGHT ANOMALIES EXCEED +210 METERS WELL NORTHEAST 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 FAR SOUTHERN CONUS. A BROAD
MID-LEVEL TROUGH AND NEAR TO BELOW NORMAL 500-HPA HEIGHTS IS DEPICTED OVER MOST
OF CENTRAL AND EASTERN NORTH AMERICA.
ABOVE NORMAL TEMPERATURES ARE FAVORED ACROSS NEARLY ALL OF MAINLAND ALASKA,
SOUTHEAST ALASKA, THE WEST COAST STATES OF THE CONUS, THE FAR SOUTHERN CONUS
FROM ARIZONA EASTWARD TO THE LOWER MISSISSIPPI VALLEY, MUCH OF THE OHIO AND
TENNESSEE VALLEYS, THE MID-ATLANTIC STATES, AND THE SOUTHEAST. THIS IS
ASSOCIATED WITH RIDGING AND/OR NEAR TO ABOVE NORMAL MID-LEVEL HEIGHTS, AND IS
CONSISTENT WITH BIAS-CORRECTED AND REFORECAST- CALIBRATED TEMPERATURE TOOLS
FROM THE VARIOUS ENSEMBLE MEAN MODEL RUNS. THE GREATEST PROBABILITIES FOR ABOVE
NORMAL TEMPERATURES (>70%) ARE INDICATED OVER SOUTHERN TEXAS, SOUTHERN
LOUISIANA, AND FLORIDA. BELOW NORMAL TEMPERATURE CHANCES ARE INCREASED FROM
EASTERN SECTIONS OF THE NORTHERN AND CENTRAL INTERMOUNTAIN WEST EASTWARD ACROSS
THE NORTHERN AND CENTRAL PLAINS TO THE UPPER MISSISSIPPI VALLEY AND WESTERN
GREAT LAKES REGION, AND PARTS OF THE NORTHEAST. THIS IS ASSOCIATED WITH
MID-LEVEL TROUGHING AND NEAR TO 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 MUCH OF WESTERN ALASKA, ASSOCIATED WITH THE MID-LEVEL
TROUGH OVER THE BERING SEA. BELOW NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR
FAR NORTHEASTERN ALASKA 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. THOUGH MOST AREAS EAST OF THE PLAINS ARE SLIGHTLY FAVORED TO GET
ABOVE NORMAL PRECIPITATION DURING THE FORECAST PERIOD, ENHANCED PROBABILITIES
FOR ABOVE NORMAL PRECIPITATION (>40%) EXTEND ACROSS THE CENTRAL AND
SOUTH-CENTRAL MISSISSIPPI VALLEY TO THE TENNESSEE VALLEY, GENERALLY OUTLINING
THE 500-HPA RIDGE-TROUGH PATTERN ANTICIPATED ACROSS THE CONUS. INDIVIDUAL
DISTURBANCES MOVING ACROSS THE GREAT LAKES AND NORTHEAST RESULT IN A >40%
CHANCE OF ABOVE NORMAL PRECIPITATION FOR THESE AREAS. BELOW NORMAL
PRECIPITATION CHANCES ARE INCREASED FOR MUCH OF THE SOUTHWEST 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: NEAR AVERAGE, 3 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 08 - 14 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 EASTERN
ALEUTIANS/WESTERN PENINSULA OF ALASKA. A STRONG ANOMALOUS RIDGE IS INDICATED
OVER NORTHERN AND EASTERN ALASKA AND NORTHWESTERN CANADA, WITH MAXIMUM
MID-LEVEL HEIGHT ANOMALIES OF +150 METERS ABOVE NORMAL ABOUT HALFWAY BETWEEN
UTQIAGVIK (BARROW) AND THE NORTH POLE OVER THE ARCTIC OCEAN. A BROAD TROUGH IS
DEPICTED OVER CENTRAL AND EASTERN PORTIONS OF NORTH AMERICA. SUBTROPICAL
RIDGING AND ABOVE NORMAL MID-LEVEL HEIGHTS ARE PREDICTED ACROSS THE SOUTHERN
CONUS. A SLIGHTLY STRONGER TROUGH IS FORECAST NEAR THE WEST COAST OF THE CONUS,
RELATIVE TO THE EARLIER 6-10 DAY PERIOD.
BIAS-CORRECTED AND REFORECAST-CALIBRATED TEMPERATURE TOOLS FAVOR ABOVE NORMAL
TEMPERATURES OVER NEARLY ALL OF MAINLAND ALASKA AND SOUTHEAST ALASKA IN THE
WEEK-2 PERIOD, UNDER MOSTLY RIDGING AND POSITIVE 500-HPA HEIGHT ANOMALIES.
BELOW NORMAL TEMPERATURE CHANCES ARE INCREASED OVER THE ALEUTIANS, IN PROXIMITY
TO A DEEPENING MID-LEVEL TROUGH. FOR THE CONUS, ABOVE NORMAL TEMPERATURE
CHANCES ARE INCREASED OVER INTERIOR SECTIONS OF WASHINGTON AND OREGON AHEAD OF
A WEAK TROUGH AXIS. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED ACROSS THE
SOUTHERN STATES FROM ARIZONA AND NEW MEXICO EASTWARD ACROSS THE SOUTHERN
PLAINS, AND MUCH OF THE MIDDLE AND LOWER MISSISSIPPI VALLEY. FROM THERE, THE
AREA OF FAVORED ABOVE NORMAL TEMPERATURES EXTENDS EASTWARD TO THE ATLANTIC
SEABOARD, FROM SOUTHERN NEW YORK TO FLORIDA. MAXIMUM PROBABILITIES FOR ABOVE
NORMAL TEMPERATURES EXCEED 70% OVER PARTS OF EASTERN TEXAS AND THE FLORIDA
PENINSULA. THIS IS SUPPORTED BY REFORECAST-CALIBRATED TEMPERATURE TOOLS FROM
THE GFS AND ECMWF ENSEMBLE MEAN MODELS. BELOW NORMAL TEMPERATURES ARE FAVORED
FROM EASTERN SECTIONS OF THE INTERMOUNTAIN WEST EASTWARD ACROSS THE NORTHERN
AND CENTRAL PLAINS, THE UPPER MISSISSIPPI VALLEY, AND UPPER MICHIGAN,
ASSOCIATED WITH A MID-LEVEL TROUGH AND NEAR NORMAL 500-HPA HEIGHTS.
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, MUCH OF THE
GREAT PLAINS AND MISSISSIPPI VALLEY, AND CONTINUING EASTWARD TO THE ATLANTIC
COAST FROM MAINE TO VIRGINIA, AND INTERIOR PORTIONS OF THE SOUTHEAST. THE
REASONING FOR THIS IS SIMILAR TO THAT DESCRIBED ABOVE IN THE 6-10 DAY
PRECIPITATION SECTION. BELOW NORMAL PRECIPITATION CHANCES ARE ELEVATED OVER A
LARGE FRACTION OF THE SOUTHWESTERN QUARTER OF THE CONUS, SUPPORTED BY THE AUTO
AND CONSOLIDATION PRECIPITATION TOOLS, AND CONSISTENT WITH A WEAKENED AND
SOUTHWARD-SHIFTED MONSOON. BELOW NORMAL PRECIPITATION IS ALSO FAVORED OVER FAR
NORTHEASTERN ALASKA, IN PROXIMITY TO A MID-LEVEL RIDGE AND WELL ABOVE NORMAL
500-HPA HEIGHTS. ABOVE NORMAL PRECIPITATION IS FAVORED FOR CENTRAL AND SOUTHERN
ALASKA IN A WIDESPREAD ONSHORE FLOW REGIME AHEAD OF A DEEP ALEUTIAN 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: 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:
19940812 - 19570814 - 19610729 - 19540808 - 19890711
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 - 19570812 - 19890710 - 19610728 - 19980730
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 06 - 10 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF A A
SRN CALIF A N IDAHO B A NEVADA A N
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B 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 B W TEXAS A N
MINNESOTA B N IOWA B A MISSOURI B A
ARKANSAS A A LOUISIANA A A WISCONSIN B A
ILLINOIS N A MISSISSIPPI A A MICHIGAN N A
INDIANA N A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK N A
VERMONT N A NEW HAMP N A MAINE N A
MASS N A CONN N A RHODE IS N 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 N AK N SLOPE A N
AK ALEUTIAN N A AK WESTERN A A AK INT BSN A N
AK S INT A A AK SO COAST A A AK PNHDL A N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 08 - 14 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON N A NRN CALIF N N
SRN CALIF N N IDAHO B A NEVADA N B
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B B ARIZONA A B COLORADO B N
NEW MEXICO A B 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 A A MISSISSIPPI A A MICHIGAN N A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK N A
VERMONT N A NEW HAMP N A MAINE N A
MASS N N CONN N A RHODE IS N N
PENN A A NEW JERSEY A A W VIRGINIA A A
MARYLAND A A DELAWARE A N VIRGINIA A A
N CAROLINA A N 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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