845
FXUS06 KWBC 311911
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE OCTOBER 31 2023
6-10 DAY OUTLOOK FOR NOV 06 - 10 2023
THE LATEST GEFS, CANADIAN, AND ECMWF ENSEMBLE MEANS ARE IN GOOD AGREEMENT
PREDICTING AN AMPLIFIED 500-HPA RIDGE OVER THE ALEUTIAN ISLANDS AND AN
AMPLIFIED TROUGH DOWNSTREAM OVER THE NORTH PACIFIC. OVER THE CONTIGUOUS U.S.
(CONUS), THE GEFS, ECMWF AND CANADIAN ENSEMBLE MEAN FORECASTS ARE IN GOOD
AGREEMENT, PREDICTING A RIDGE OVER WESTERN CANADA AND THE WESTERN CONUS AND A
TROUGH OVER EASTERN NORTH AMERICA. ALL ENSEMBLE MEANS PREDICT A MORE AMPLIFIED
TROUGH OVER THE EASTERN CONUS IN THE 6-10 DAY PERIOD RELATIVE TO YESTERDAY’S
ENSEMBLE MEAN FORECASTS, AND THE GEFS ENSEMBLE MEAN TROUGH IS MORE AMPLIFIED
THAN THE ECMWF.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MOST OF MAINLAND ALASKA, EXCLUDING
WESTERN AREAS, AND FOR SOUTHEAST ALASKA, WITH PREDICTED SOUTHERLY FLOW AND
POSITIVE 500-HPA HEIGHT ANOMALIES OVER MOST OF THE STATE. ABOVE NORMAL
TEMPERATURES ARE FAVORED FOR THE WESTERN AND SOUTH-CENTRAL CONUS, UNDER A
PREDICTED RIDGE. WEAK PROBABILITIES FAVORING ABOVE NORMAL TEMPERATURES ARE
FORECAST ACROSS THE SOUTHEAST, CONSISTENT WITH THE CONSOLIDATION OF GEFS AND
ECMWF REFORECAST-CALIBRATED TEMPERATURES, AS A MORE AMPLIFIED TROUGH IS
PREDICTED OVER THE REGION LATER IN THE PERIOD. BELOW NORMAL TEMPERATURES ARE
FAVORED FOR MOST OF THE NORTHEAST, UNDER A PREDICTED MEAN TROUGH. ABOVE NORMAL
TEMPERATURES ARE FAVORED ACROSS THE HAWAIIAN ISLANDS, AS INDICATED BY THE
CONSOLIDATION OF MODEL TEMPERATURE TOOLS.
ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR MOST OF MAINLAND ALASKA,
CONSISTENT WITH DYNAMICAL MODEL PRECIPITATION TOOLS. ABOVE NORMAL PRECIPITATION
IS LIKELY FOR THE PACIFIC NORTHWEST, AHEAD OF A PREDICTED AMPLIFIED TROUGH OVER
THE NORTHEAST PACIFIC. ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS MOST OF THE
NORTHERN TIER OF THE CONUS, CONSISTENT WITH DYNAMICAL MODEL PRECIPITATION
TOOLS. ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR MUCH OF THE EASTERN
CONUS, UNDER THE PREDICTED MID-LEVEL TROUGH. BELOW NORMAL PRECIPITATION IS
FAVORED FOR PARTS OF THE SOUTHWESTERN AND SOUTH-CENTRAL CONUS, UNDER A
PREDICTED RIDGE. ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED ACROSS THE
HAWAIIAN ISLANDS, CONSISTENT WITH THE PRECIPITATION CONSOLIDATION.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 35% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 30% 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, DUE TO
GOOD AGREEMENT ON AN AMPLIFIED MID-LEVEL HEIGHT PATTERN OVER NORTH AMERICA,
OFFSET BY A VARIABLE PATTERN OVER THE EASTERN CONUS.
8-14 DAY OUTLOOK FOR NOV 08 - 14 2023
THE PREDICTED 500-HPA CIRCULATION PATTERN FOR THE WEEK-2 PERIOD IS SIMILAR TO
THE FORECAST FOR THE 6-10 DAY PERIOD, WITH SOME EVOLUTION OF THE PATTERN. A
LESS AMPLIFIED RIDGE PERSISTS OVER THE ALEUTIANS AND A TROUGH CONTINUES TO BE
FORECAST OVER THE NORTHEASTERN PACIFIC, WITH A SLIGHT EASTWARD PROGRESSION AND
DE-AMPLIFICATION DURING THE PERIOD. THE 500-HPA RIDGE-TROUGH PATTERN OVER THE
CONUS PERSISTS INTO WEEK 2. THE GEFS ENSEMBLE MEAN PREDICTS A MORE AMPLIFIED
TROUGH OVER THE EAST IN WEEK 2 COMPARED TO THE ECMWF ENSEMBLE MEAN.
ABOVE NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR MOST OF ALASKA OUTSIDE OF
THE WEST-CENTRAL COAST OF MAINLAND ALASKA, CONSISTENT WITH MOST DYNAMICAL MODEL
TEMPERATURE TOOLS. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN AND
CENTRAL CONUS FOR WEEK 2, UNDER A PERSISTENT RIDGE AND ASSOCIATED POSITIVE
500-HPA HEIGHT ANOMALIES. BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE EASTERN
CONUS, UNDER A PREDICTED TROUGH, WHILE PROBABILITIES FOR BELOW NORMAL
TEMPERATURES ARE LOWER FOR THE SOUTHEAST, WITH A VARIABLE MID-LEVEL HEIGHT
PATTERN. ABOVE NORMAL TEMPERATURES CONTINUE TO BE FAVORED FOR THE HAWAIIAN
ISLANDS, AS PREDICTED BY DYNAMICAL MODEL TEMPERATURE TOOLS.
ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR THE NORTH SLOPE AND SOUTHERN
MAINLAND ALASKA, CONSISTENT WITH PRECIPITATION FORECAST TOOLS. ABOVE NORMAL
PRECIPITATION IS FAVORED FOR SOUTHEAST ALASKA INCLUDING THE ALASKA PANHANDLE,
AND FOR THE PACIFIC COAST OF THE CONUS, AHEAD OF THE PREDICTED TROUGH.
NEAR-TO-BELOW NORMAL PRECIPITATION IS FAVORED FOR THE SOUTHWEST, UNDER THE
PREDICTED RIDGE. ABOVE NORMAL PRECIPITATION IS FAVORED FOR PARTS OF THE GREAT
PLAINS WITH SOUTHERLY MOISTURE FLOW AROUND SURFACE HIGH PRESSURE. BELOW NORMAL
PRECIPITATION IS SLIGHTLY FAVORED FOR MUCH OF THE SOUTHEASTERN CONUS, AS THE
EAST DRIES OUT CONSISTENT WITH THE PRECIPITATION CONSOLIDATION. ABOVE NORMAL
PRECIPITATION CONTINUES TO BE SLIGHTLY FAVORED FOR PARTS OF NEW ENGLAND,
CONSISTENT WITH DYNAMICAL MODEL FORECASTS. ABOVE NORMAL PRECIPITATION IS
SLIGHTLY FAVORED FOR MOST OF THE ISLANDS OF HAWAII OUTSIDE OF SOUTHEASTERN
AREAS OF THE BIG ISLAND, AS PREDICTED BY THE PRECIPITATION CONSOLIDATION.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 30% 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
GOOD OVERALL AGREEMENT BETWEEN MODEL FORECASTS ON THE 500-HPA HEIGHT PATTERN IN
WEEK-2, OFFSET BY INCREASING UNCERTAINTY IN BOTH TEMPERATURE AND PRECIPITATION
TOOLS ALONG WITH A VARIABLE CIRCULATION PATTERN.
FORECASTER: D COLLINS
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
NOVEMBER 16.
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:
19811022 - 19931105 - 19861110 - 19861031 - 19601018
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:
19811021 - 19791109 - 19861109 - 19931105 - 19861103
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 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 A A NEVADA A A
W MONTANA A A E MONTANA N A WYOMING A A
UTAH A B ARIZONA A B COLORADO A N
NEW MEXICO A B N DAKOTA B A S DAKOTA N A
NEBRASKA A A KANSAS A N OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA B A IOWA B A MISSOURI N A
ARKANSAS A N LOUISIANA A B WISCONSIN B A
ILLINOIS B A MISSISSIPPI A N MICHIGAN B A
INDIANA B A OHIO B A KENTUCKY N A
TENNESSEE N A ALABAMA A N NEW YORK B A
VERMONT B A NEW HAMP B A MAINE B A
MASS B A CONN B A RHODE IS B A
PENN B A NEW JERSEY B A W VIRGINIA B A
MARYLAND B 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 A A
AK ALEUTIAN N A AK WESTERN N A AK INT BSN A A
AK S INT A A AK SO COAST A A AK PNHDL A N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 08 - 14 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 A N NEVADA A N
W MONTANA A N E MONTANA A N WYOMING A N
UTAH A N ARIZONA A B COLORADO A N
NEW MEXICO A N N DAKOTA A N S DAKOTA A A
NEBRASKA A A KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A A W TEXAS A A
MINNESOTA N N IOWA N N MISSOURI N N
ARKANSAS N N LOUISIANA A N WISCONSIN B N
ILLINOIS B N MISSISSIPPI N B MICHIGAN B N
INDIANA B N OHIO B N KENTUCKY B B
TENNESSEE B B ALABAMA B B NEW YORK B N
VERMONT B N NEW HAMP B A MAINE B A
MASS B A CONN B A RHODE IS B A
PENN B N NEW JERSEY B N W VIRGINIA B N
MARYLAND B N DELAWARE B N VIRGINIA B N
N CAROLINA B B S CAROLINA B B GEORGIA B B
FL PNHDL B B FL PENIN B B AK N SLOPE A A
AK ALEUTIAN A N AK WESTERN A A AK INT BSN A N
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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