559
FXUS06 KWBC 092028
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE JANUARY 09 2024
6-10 DAY OUTLOOK FOR JAN 15 - 19 2024
TODAY'S MODEL SOLUTIONS ARE IN VERY GOOD AGREEMENT ON THE PREDICTED AMPLIFIED
500-HPA CIRCULATION PATTERN ACROSS NORTH AMERICA AND SURROUNDING REGIONS DURING
THE 6-10 DAY PERIOD. THE MANUAL 500-HPA HEIGHT BLEND IS BASED ON THE 0Z
ENSEMBLE MEANS FROM THE GEFS, ECMWF, AND CANADIAN MODELS, WEIGHTING THE ECMWF
AND GEFS MODELS SLIGHTLY HIGHER DUE TO RECENT MODEL SKILL. SPLIT MID-LEVEL FLOW
IS FORECAST OVER THE ALEUTIANS AND NORTH PACIFIC, WITH A SHORTWAVE TROUGH TO
THE SOUTH AND A RIDGE OVER THE BERING SEA. AN AMPLIFIED, NEGATIVELY TILTED
TROUGH AND ASSOCIATED NEGATIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST OVER MOST
OF THE CONTIGUOUS U.S. (CONUS), WHILE POSITIVE 500-HPA HEIGHT ANOMALIES ARE
FORECAST ALONG THE WEST COAST IN THE ENSEMBLE MEANS. NEGATIVE 500-HPA HEIGHT
ANOMALIES ARE FORECAST CENTERED TO THE NORTH OF HAWAII.
BELOW-NORMAL TEMPERATURES ARE FAVORED OVER PARTS OF THE NORTHWEST, AND
PROBABILITIES FOR BELOW-NORMAL TEMPERATURES ARE MUCH ENHANCED OVER THE CENTRAL
AND EASTERN CONUS, UNDER AN AMPLIFIED TROUGH, ORIENTED FROM NORTHWEST TO
SOUTHEAST. THESE MUCH ENHANCED PROBABILITIES COINCIDE WITH WHERE ARCTIC HIGH
PRESSURE SHIFTS SOUTH AND EAST FROM THE GREAT PLAINS TO THE OHIO VALLEY. THE
GREATEST PROBABILITIES FOR BELOW-NORMAL TEMPERATURES EXCEED 90 PERCENT OVER
MUCH OF THE CENTRAL PLAINS AND MIDDLE MISSISSIPPI VALLEY. ABOVE-NORMAL
TEMPERATURES ARE FAVORED ALONG THE WEST COAST WITH ONSHORE FLOW PREVAILING.
THERE IS MORE UNCERTAINTY IN THE FORECAST FOR ALASKA, WITH A WIDER RANGE OF
MODEL SOLUTIONS. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE WESTERN
AND NORTHERN PORTIONS OF THE STATE, WHILE BELOW-NORMAL TEMPERATURES ARE
SLIGHTLY FAVORED FOR SOUTHEAST ALASKA, UNDER ANOMALOUS NORTHERLY FLOW. FOR
HAWAII, THE AUTOMATED BLEND OF FORECAST TOOLS FAVORS NEAR-NORMAL TEMPERATURES
FOR THE NORTHWESTERN ISLAND OF KAUAI AND ABOVE-NORMAL TEMPERATURES FOR THE REST
OF THE STATE.
WITH SURFACE LOW PRESSURE DURING THE 6-10 DAY PERIOD CENTERED WELL AWAY FROM
THE ALASKAN COAST, BELOW-NORMAL PRECIPITATION IS FAVORED FOR MUCH OF THE
WESTERN AND SOUTHERN PORTIONS OF THE STATE. CYCLONIC MID-LEVEL FLOW AND A LOW
PRESSURE SYSTEM MOVING EASTWARD INTO THE NORTHWESTERN CONUS DURING THE PERIOD
FAVORS ABOVE-NORMAL PRECIPITATION FROM THE PACIFIC NORTHWEST ACROSS THE
NORTHERN ROCKIES INTO THE NORTHERN PLAINS. ABOVE-NORMAL PRECIPITATION IS ALSO
SLIGHTLY FAVORED FOR PORTIONS OF THE GREAT LAKES REGION PRONE TO LAKE-EFFECT
SNOW. BELOW-NORMAL PRECIPITATION IS FAVORED ACROSS MUCH OF THE SOUTHWEST AND
CENTRAL PLAINS AS WELL AS THE MIDDLE AND UPPER MISSISSIPPI AND OHIO VALLEYS.
ABOVE-NORMAL PRECIPITATION REMAINS FAVORED FOR PORTIONS OF THE SOUTHEAST U.S.
WITH LINGERING STORMINESS ASSOCIATED WITH THE EXITING TROUGH. NEAR-NORMAL
PRECIPITATION IS FORECAST FOR THE BIG ISLAND OF HAWAII AND THE REST OF THE
STATE TILTS SLIGHTLY TOWARDS ABOVE-NORMAL PRECIPITATION, CONSISTENT WITH A
BLEND OF MODEL FORECAST TOOLS.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 38% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 37% 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, DUE TO
GOOD AGREEMENT AMONG MODEL SOLUTIONS ON AN AMPLIFIED MID-LEVEL CIRCULATION
PATTERN AND AMONG TEMPERATURE AND PRECIPITATION FORECAST TOOLS FOR THE CONUS,
OFFSET BY SIGNIFICANT UNCERTAINTY IN THE FORECAST FOR ALASKA.
8-14 DAY OUTLOOK FOR JAN 17 - 23 2024
ENSEMBLE MEAN SOLUTIONS FOR THE 8-14 DAY PERIOD GENERALLY PREDICT A SIMILAR
500-HPA CIRCULATION PATTERN TO THE 6-10 DAY PERIOD ACROSS NORTH AMERICA AND THE
SURROUNDING REGIONS, WITH SOME EASTWARD PROGRESSION OF THE PATTERN OVER THE
CONUS. POSITIVE 500-HPA HEIGHT ANOMALIES PERSIST CENTERED TO THE NORTHWEST OF
MAINLAND ALASKA IN THE WEEK-2 PERIOD, BUT DIFFERENCES AMONG THE ECMWF, GEFS,
AND CANADIAN TEMPERATURE AND PRECIPITATION TOOLS CONTINUE. THE PREDICTED TROUGH
OVER THE CONUS PROGRESSES EASTWARD, WITH NEGATIVE 500-HPA HEIGHT ANOMALIES OVER
THE EASTERN HALF OF THE CONUS. BELOW-AVERAGE 500-HPA HEIGHTS CONTINUE TO BE
CENTERED TO THE NORTH OF HAWAII IN THE GEFS AND ECMWF ENSEMBLE MEAN SOLUTIONS.
BELOW-NORMAL TEMPERATURES ARE LIKELY OVER MOST OF THE EASTERN TWO-THIRDS OF THE
CONUS, FROM THE NORTHERN ROCKIES AND GREAT PLAINS EASTWARD, UNDER THE PREDICTED
TROUGH. ABOVE-NORMAL TEMPERATURES ARE LIKELY FOR MUCH OF THE WEST COAST, GREAT
BASIN, AND DESERT SOUTHWEST UNDER RISING MID-LEVEL HEIGHTS. WITH UNCERTAINTY
AMONG THE MODEL TEMPERATURE FORECAST TOOLS, NEAR-NORMAL TEMPERATURES ARE
FORECAST ACROSS MOST OF ALASKA. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR
NORTHWESTERN ALASKA, UNDER A PREDICTED RIDGE. BELOW-NORMAL TEMPERATURES ARE
FAVORED FOR SOUTHEAST ALASKA UNDER ANOMALOUS NORTHEASTERLY MID-LEVEL FLOW.
ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR HAWAIIAN ISLANDS, CONSISTENT WITH
MODEL TEMPERATURE TOOLS.
THERE ARE INCREASING CHANCES OF ABOVE-NORMAL PRECIPITATION ACROSS MUCH OF THE
WESTERN CONUS, AS MODELS PREDICT A POTENTIAL STORM SYSTEM OFF OF THE PACIFIC
COAST, WITH SLIGHTLY ENHANCED PROBABILITIES OF ABOVE-NORMAL PRECIPITATION
EXTENDING AS FAR EASTWARD AS WESTERN AREAS OF THE NORTHERN PLAINS. INCREASED
RETURN FLOW AROUND SURFACE HIGH PRESSURE OVER THE EASTERN CONUS ALSO ENHANCES
CHANCES FOR ABOVE-NORMAL PRECIPITATION FOR THE SOUTHERN PLAINS. SURFACE HIGH
PRESSURE, SHIFTING EASTWARD, INCREASES THE CHANCES OF BELOW-NORMAL
PRECIPITATION OVER THE NORTHEASTERN CONUS. NEAR-NORMAL PRECIPITATION IS FAVORED
FOR MOST OF HAWAII EXCEPT FOR THE BIG ISLAND, WHICH TILTS TOWARD BELOW-NORMAL
PRECIPITATION BY A BLEND OF MODEL PRECIPITATION TOOLS.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 34% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 33% 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, DUE TO
GOOD AGREEMENT AMONG MODEL SOLUTIONS ON THE OVERALL MID-LEVEL CIRCULATION
PATTERN, OFFSET BY WEAKER PROBABILITIES IN TEMPERATURE AND PRECIPITATION TOOLS.
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
JANUARY 18.
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:
19670105 - 19640106 - 19661231 - 20071227 - 19640114
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:
19670104 - 19661230 - 19550120 - 19640112 - 19790119
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 15 - 19 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF A A
SRN CALIF N B IDAHO B A NEVADA B B
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B B ARIZONA N B COLORADO B A
NEW MEXICO B B N DAKOTA B N S DAKOTA B N
NEBRASKA B N KANSAS B B OKLAHOMA B B
N TEXAS B B S TEXAS B N W TEXAS B B
MINNESOTA B N IOWA B B MISSOURI B B
ARKANSAS B B LOUISIANA B N WISCONSIN B N
ILLINOIS B B MISSISSIPPI B N MICHIGAN B N
INDIANA B N OHIO B N KENTUCKY B N
TENNESSEE B N ALABAMA B A NEW YORK B N
VERMONT B N NEW HAMP B N MAINE N A
MASS B N CONN B N RHODE IS B N
PENN B N NEW JERSEY B N W VIRGINIA B N
MARYLAND B N DELAWARE B N VIRGINIA B N
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN B A AK N SLOPE A N
AK ALEUTIAN A B AK WESTERN A B AK INT BSN A N
AK S INT N N AK SO COAST N B AK PNHDL B N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 17 - 23 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON N A NRN CALIF A A
SRN CALIF A A IDAHO B A NEVADA A A
W MONTANA B A E MONTANA B A WYOMING B A
UTAH A A ARIZONA A A COLORADO B A
NEW MEXICO B A N DAKOTA B N S DAKOTA B N
NEBRASKA B N KANSAS B N OKLAHOMA B N
N TEXAS B A S TEXAS B A W TEXAS B A
MINNESOTA B N IOWA B N MISSOURI B B
ARKANSAS B N LOUISIANA B A WISCONSIN B B
ILLINOIS B B MISSISSIPPI B N MICHIGAN B B
INDIANA B B OHIO B B KENTUCKY B B
TENNESSEE B B ALABAMA B B NEW YORK B B
VERMONT B B NEW HAMP B B MAINE B B
MASS B B CONN B B RHODE IS B B
PENN B B NEW JERSEY B B W VIRGINIA B B
MARYLAND B B DELAWARE B B VIRGINIA B B
N CAROLINA B B S CAROLINA B B GEORGIA B B
FL PNHDL B N FL PENIN B A AK N SLOPE A N
AK ALEUTIAN A N AK WESTERN N B AK INT BSN N B
AK S INT N B AK SO COAST N N 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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