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FXUS06 KWBC 211908
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED JUNE 21 2023
6-10 DAY OUTLOOK FOR JUN 27 - JUL 01, 2023
THE GFS, ECWMF, AND CANADIAN ENSEMBLE MEAN FORECASTS ARE IN VERY GOOD AGREEMENT
TODAY REGARDING THE 500-HPA CIRCULATION PATTERN OVER THE NORTH AMERICAN DOMAIN
DURING THE 6-10 DAY PERIOD, AND SHOW GOOD CONTINUITY WITH YESTERDAY’S MODEL
SOLUTIONS. THE PREDICTED PRIMARY LONGWAVE FEATURES INCLUDE 5-DAY MEAN TROUGHS
AND BELOW AVERAGE 500-HPA HEIGHTS OVER THE VICINITY OF THE BERING SEA, THE
EASTERN QUARTER OF THE CONTIGUOUS U.S. (CONUS), AND THE NEAR THE WEST COAST
(THOUGH HERE THE 500-HPA HEIGHTS ARE PREDICTED TO BE NEAR AVERAGE). MEAN RIDGES
AND ABOVE AVERAGE 500-HPA HEIGHTS ARE EXPECTED OVER THE SOUTHWESTERN AND
SOUTH-CENTRAL CONUS, AND WESTERN CANADA/SOUTHEAST ALASKA.
ABOVE NORMAL TEMPERATURES ARE FAVORED OVER PORTIONS OF THE PACIFIC NORTHWEST
AND NORTHERN GREAT BASIN IN PROXIMITY TO THE ANOMALOUS RIDGE CENTERED ACROSS
FAR WESTERN CANADA, AND PREDICTED ABOVE AVERAGE 500-HPA HEIGHTS. ODDS FAVOR
ABOVE NORMAL TEMPERATURES FOR PORTIONS OF THE DESERT SOUTHWEST, SOUTHERN
ROCKIES, THE SOUTHERN HALF OF THE GREAT PLAINS, THE LOWER AND MIDDLE
MISSISSIPPI VALLEY, AND PORTIONS OF THE SOUTHEAST. MAXIMUM PROBABILITIES FOR
ABOVE NORMAL TEMPERATURES EXCEED 80% OVER TEXAS. THE WIDESPREAD AREA OF FAVORED
ABOVE NORMAL TEMPERATURES IS SUPPORTED BY THE BIAS-CORRECTED AND REFORECAST
TEMPERATURE TOOLS FROM THE VARIOUS ENSEMBLE MEANS, AND IS GENERALLY CONSISTENT
WITH MID-LEVEL RIDGING AND POSITIVE 500-HPA HEIGHT ANOMALIES. THE VARIOUS
REFORECAST TEMPERATURE TOOLS DEPICT ABOVE NORMAL TEMPERATURES OVER NEW ENGLAND,
WHICH IS CONSISTENT GIVEN THE FORECAST MID-LEVEL TROUGH AXIS JUST WEST OF THAT
REGION. ABOVE NORMAL TEMPERATURE CHANCES ARE SLIGHTLY ENHANCED OVER FAR
NORTHEASTERN PARTS OF ALASKA, INFLUENCED BY A NEARBY MID-LEVEL RIDGE. BELOW
NORMAL TEMPERATURES ARE FAVORED OVER MOST OF ALASKA SOUTH OF THE BROOKS RANGE
IN PROXIMITY TO A MID-LEVEL TROUGH AND BELOW NORMAL MID-TROPOSPHERIC HEIGHTS.
THERE ARE ELEVATED ODDS OF BELOW NORMAL TEMPERATURES OVER PORTIONS OF
CALIFORNIA AND NEVADA, AND THE NORTH-CENTRAL GREAT PLAINS AS INDICATED BY THE
TEMPERATURE CONSOLIDATION TOOL. BELOW NORMAL TEMPERATURES ARE ALSO FAVORED OVER
THE GREAT LAKES REGION, EASTERN CORN BELT/OHIO VALLEY, UPPER TENNESSEE VALLEY,
MOST OF THE APPALACHIANS, AND THE MID-ATLANTIC REGION COINCIDENT WITH, AND WEST
OF A MID-LEVEL TROUGH AXIS AND BELOW NORMAL HEIGHTS.
ABOVE NORMAL PRECIPITATION CHANCES ARE ENHANCED FROM NORTHERN AND CENTRAL
CALIFORNIA AND MOST OF OREGON AND WASHINGTON EASTWARD ACROSS NORTHERN AND
CENTRAL PORTIONS OF THE GREAT BASIN, APPROXIMATELY THE NORTHWESTERN HALF OF THE
ROCKIES, THE NORTHERN AND CENTRAL PLAINS, AND PARTS OF THE UPPER MISSISSIPPI
VALLEY. THIS IS SUPPORTED BY REFORECAST PRECIPITATION OUTPUT FROM THE VARIOUS
ENSEMBLE MEANS, AND IS CONSISTENT WITH THE MID-LEVEL TROUGH PREDICTED NEAR THE
WEST COAST. ABOVE NORMAL PRECIPITATION CHANCES ARE INCREASED FROM THE CENTRAL
GREAT LAKES REGION AND OHIO/TENNESSEE VALLEYS EASTWARD TO THE ATLANTIC SEABOARD
FROM MAINE TO SOUTH CAROLINA. THIS IS DUE TO A COMBINATION OF FACTORS WHICH
INCLUDE: THE PROXIMITY OF A MID-LEVEL TROUGH AND ACCOMPANYING BELOW NORMAL
500-HPA HEIGHTS, AND WEAK DISTURBANCES MOVING OVER THE CREST OF THE HIGH PLAINS
RIDGE AND CONTINUING ACROSS THE NOTED REGION IN NORTHWEST FLOW ALOFT. ABOVE
NORMAL PRECIPITATION CHANCES ARE INCREASED OVER MOST OF ALASKA, COINCIDENT WITH
AND EAST OF A PREDICTED MID-LEVEL TROUGH. BELOW NORMAL PRECIPITATION IS FAVORED
FROM THE DESERT SOUTHWEST AND FOUR CORNERS REGION EASTWARD OVER THE SOUTHERN
ROCKIES, SOUTHERN GREAT PLAINS, AND LOWER MISSISSIPPI VALLEY UNDER MID-LEVEL
RIDGING AND MODESTLY ABOVE NORMAL 500-HPA HEIGHTS. BELOW NORMAL PRECIPITATION
CHANCES ARE ALSO SLIGHTLY ENHANCED OVER THE FAR SOUTHERN PANHANDLE OF SOUTHEAST
ALASKA, IN PROXIMITY TO A MID-LEVEL RIDGE.
TROPICAL STORM BRET (JUN 21, 11AM AST) IS FORECAST TO TRACK WESTWARD DURING THE
NEXT 5 DAYS OVER THE LOW LATITUDES OF THE ATLANTIC BASIN AND MOST OF THE
CARIBBEAN SEA. AT THIS TIME, IT IS TOO EARLY TO TELL WHERE OR IF BRET WILL HAVE
ANY INFLUENCE ON THE SOUTHERN CONUS, AND THEREFORE REMAINS A SIGNIFICANT
WILDCARD IN THIS 6-10 DAY PRECIPITATION FORECAST. WELL TO THE EAST OF BRET IS
ANOTHER TROPICAL SYSTEM WHICH IS ALSO TRACKING WESTWARD, WHICH HAS A 70% CHANCE
OF DEVELOPING INTO A TROPICAL CYCLONE WITHIN THE NEXT 48 HOURS. AT THIS TIME IT
APPEARS THE SYSTEM WILL REMAIN FAR OUT OVER THE ATLANTIC AND NOT POSE A PROBLEM
FOR THE CONUS, THOUGH IT STILL NEEDS TO BE CAREFULLY MONITORED FOR ANY NEW
DEVELOPMENTS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 34% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 33% 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
UPON VERY GOOD CONSENSUS AMONG THE DYNAMICAL 500-HPA HEIGHT MODELS, AND GOOD
AGREEMENT AMONG SURFACE TEMPERATURE AND PRECIPITATION TOOLS.
8-14 DAY OUTLOOK FOR JUN 29 - JUL 05, 2023
THE GFS, ECWMF, AND CANADIAN ENSEMBLE MEAN FORECASTS ARE IN GOOD AGREEMENT
TODAY ON THE PREDICTED 500-HPA CIRCULATION PATTERN OVER THE NORTH AMERICAN
DOMAIN DURING WEEK-2. SIMILAR TO THE PREDICTED 6-10 DAY CIRCULATION PATTERN,
THE WEEK-2 FORECAST FEATURES MEAN TROUGHS OVER THE VICINITY OF THE BERING SEA,
THE WEST COAST OF THE CONUS, AND THE EASTERN CONUS. MEAN RIDGES AND ABOVE
AVERAGE 500-HPA HEIGHTS ARE EXPECTED OVER THE SOUTHWESTERN AND SOUTH-CENTRAL
CONUS, AND WESTERN CANADA/SOUTHEAST ALASKA. THE SUBTROPICAL RIDGE ACROSS THE
SOUTHWESTERN AND SOUTH-CENTRAL CONUS IS FORECAST BY THE ENSEMBLE MEAN SOLUTIONS
AND THE 0Z/6Z DETERMINISTIC GFS SOLUTIONS TO EXPAND WESTWARD, APPROACHING ITS
SUMMERTIME MEAN CLIMATOLOGICAL POSITION NEAR THE FOUR CORNERS REGION. THIS
WESTWARD SHIFT OF THE RIDGE TOWARDS THE FOUR CORNERS REGION IN EARLY SUMMER IS
INDICATIVE OF THE APPROACHING SOUTHWEST MONSOON SEASON.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE WESTERN AND CENTRAL
THIRDS OF THE CONUS, THE SOUTHEAST, AND PORTIONS OF NEW YORK AND NEW ENGLAND.
PROBABILITIES FOR ABOVE NORMAL TEMPERATURES EXCEED 70% OVER TEXAS. THIS
EXPANSIVE AREA OF RELATIVE WARMTH IS CONSISTENT WITH MID-LEVEL RIDGING AND
POSITIVE 500-HPA HEIGHT ANOMALIES, AS WELL AS A WEAKENING WEST COAST 500-HPA
TROUGH. ABOVE NORMAL TEMPERATURE CHANCES ARE SLIGHTLY ELEVATED OVER FAR
NORTHEASTERN ALASKA IN PROXIMITY TO A MID-LEVEL RIDGE AND NEAR TO ABOVE NORMAL
500-HPA HEIGHTS. BELOW NORMAL TEMPERATURES ARE FAVORED FOR MOST OF ALASKA SOUTH
OF THE BROOKS RANGE, BASED ON THE WEEK-2 TEMPERATURE CONSOLIDATION FORECAST,
AND BIAS-CORRECTED TEMPERATURES FROM THE VARIOUS ENSEMBLE MEANS. BELOW NORMAL
TEMPERATURES ARE FAVORED FROM THE VICINITY OF THE UPPER OHIO VALLEY
SOUTHEASTWARD ACROSS THE CENTRAL APPALACHIANS TO THE MID-ATLANTIC COAST, BASED
ON A SUBJECTIVE CONSENSUS OF THE OBJECTIVE TEMPERATURE TOOLS. A SMALL AREA OF
MODESTLY ENHANCED ODDS OF BELOW NORMAL TEMPERATURES IS ALSO INDICATED OVER
WYOMING.
ABOVE NORMAL PRECIPITATION CHANCES ARE ELEVATED FROM NEAR THE CASCADE MOUNTAIN
RANGE OF THE PACIFIC NORTHWEST EASTWARD ACROSS THE NORTHERN GREAT BASIN, THE
NORTHERN ROCKIES, NORTHERN AND CENTRAL PORTIONS OF THE PLAINS, PORTIONS OF THE
MISSISSIPPI VALLEY, THE OHIO AND TENNESSEE VALLEYS, THE SOUTHEAST,
APPALACHIANS, AND EAST COAST STATES FROM MAINE TO GEORGIA. THIS IS BASED ON RAW
PRECIPITATION PROBABILITIES FROM THE ENSEMBLE MEAN SOLUTIONS AND FROM THE
REFORECAST PRECIPITATION TOOLS. ABOVE NORMAL PRECIPITATION IS ALSO FAVORED OVER
MOST OF ALASKA IN PROXIMITY TO A MID-LEVEL TROUGH, NEAR TO BELOW NORMAL 500-HPA
HEIGHTS, AND PREDICTED WIDESPREAD ONSHORE FLOW. BELOW NORMAL PRECIPITATION IS
FAVORED FOR THE CENTRAL AND SOUTHERN GREAT BASIN, SOUTHERN ROCKIES, AND MUCH OF
TEXAS AND LOUISIANA. THIS IS WELL SUPPORTED BY THE AUTO AND CONSOLIDATED
PRECIPITATION TOOLS, AND THE PROXIMITY OF A MID-LEVEL RIDGE AND POSITIVE
500-HPA HEIGHT ANOMALIES. IT IS ALSO WORTH NOTING THAT SOIL MOISTURE CONDITIONS
ACROSS EASTERN TEXAS HAVE SIGNIFICANTLY DEGRADED IN THE PAST TWO WEEKS, WHICH
WILL ONLY EXACERBATE THE EXCESSIVE HEAT EXPECTED DURING THIS FORECAST PERIOD.
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: ABOVE AVERAGE, 4 OUT OF 5, BASED
ON GOOD AGREEMENT AMONG THE VARIOUS 500-HPA HEIGHT MODELS, OFFSET BY RELATIVELY
MINOR DIFFERENCES AMONG THE SURFACE TEMPERATURE AND 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
JULY 20.
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:
19980625 - 19850626 - 19890626 - 20070614 - 19760602
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:
19980625 - 19890626 - 19850626 - 19760603 - 20070614
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 27 - JUL 01, 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF B A
SRN CALIF B N IDAHO A A NEVADA N A
W MONTANA N A E MONTANA B A WYOMING B A
UTAH N B ARIZONA A B COLORADO A N
NEW MEXICO A B N DAKOTA N A S DAKOTA N A
NEBRASKA N A KANSAS A A OKLAHOMA A N
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA N A IOWA N N MISSOURI A N
ARKANSAS A N LOUISIANA A B WISCONSIN B N
ILLINOIS B N MISSISSIPPI A N MICHIGAN B N
INDIANA B N OHIO B A KENTUCKY B A
TENNESSEE B A ALABAMA A N NEW YORK N A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN N A RHODE IS A A
PENN B A NEW JERSEY N A W VIRGINIA B A
MARYLAND B A DELAWARE B A VIRGINIA B A
N CAROLINA B A S CAROLINA B A GEORGIA N N
FL PNHDL A N FL PENIN A N AK N SLOPE N A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN N A
AK S INT B A AK SO COAST B A AK PNHDL B N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 29 - JUL 05, 2023
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A N NRN CALIF A N
SRN CALIF A N IDAHO A A NEVADA A B
W MONTANA A A E MONTANA N A WYOMING N A
UTAH A B ARIZONA A B COLORADO A N
NEW MEXICO A B N DAKOTA A A S DAKOTA N A
NEBRASKA N A KANSAS A A OKLAHOMA A N
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA A N IOWA A N MISSOURI A A
ARKANSAS A N LOUISIANA A N WISCONSIN A N
ILLINOIS N N MISSISSIPPI A N MICHIGAN N N
INDIANA N N OHIO B A KENTUCKY N A
TENNESSEE N A ALABAMA A A NEW YORK N A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN N A RHODE IS A A
PENN B A NEW JERSEY N A W VIRGINIA B A
MARYLAND B A DELAWARE B A VIRGINIA B A
N CAROLINA B A S CAROLINA N A GEORGIA A A
FL PNHDL A N FL PENIN A N AK N SLOPE N A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL B 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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