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FXUS06 KWBC 111902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON MARCH 11 2024
6-10 DAY OUTLOOK FOR MAR 17 - 21 2024
THERE IS GOOD AGREEMENT AMONG THE DYNAMICAL MODELS REGARDING AN AMPLIFIED
500-HPA GEOPOTENTIAL HEIGHT PATTERN ACROSS NORTH AMERICA DURING THE 6-10 DAY
PERIOD. TROUGHING IS FAVORED ACROSS THE EASTERN U.S., WITH RIDGING INITIALLY
FORECAST ACROSS WESTERN NORTH AMERICA. LATER IN THE PERIOD, TROUGHING IS
FORECAST TO RELOAD ACROSS THE CENTRAL CONUS, WITH ANOMALOUS RIDGING
RETROGRADING ACROSS THE NORTHEASTERN PACIFIC AND ALASKA. TODAY’S 500-HPA MANUAL
HEIGHT BLEND INDICATES BELOW-NORMAL HEIGHTS FOR MUCH OF THE CONUS EAST OF THE
ROCKIES, EXCLUDING PORTIONS OF THE SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY,
AND SOUTHEAST WHERE NEAR- TO SLIGHTLY ABOVE-NORMAL HEIGHTS ARE PREDICTED. THE
LARGEST NEGATIVE HEIGHT ANOMALIES (-120 METERS) ARE PREDICTED ACROSS THE GREAT
LAKES AND INTERIOR NORTHEAST. SLIGHTLY BELOW-NORMAL HEIGHTS ARE ALSO INDICATED
ACROSS PARTS OF SOUTHERN CALIFORNIA, AND EXTENDING INTO SOUTHERN PARTS OF THE
FOUR CORNERS REGION. CONVERSELY, ABOVE-NORMAL HEIGHTS ARE FORECAST FOR THE
REMAINDER OF THE WESTERN CONUS AND ALASKA. BELOW-NORMAL HEIGHTS ARE PREDICTED
ACROSS HAWAII AS SHORTWAVE TROUGHING UNDERCUTS THE RIDGING OVER THE PACIFIC.
ELEVATED PROBABILITIES FOR BELOW-NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF
THE SOUTH-CENTRAL CONUS, THE MIDDLE AND LOWER MISSISSIPPI, OHIO, AND TENNESSEE
VALLEYS, AND SOUTHEAST AS ANOMALOUS TROUGHING LEADS TO ENHANCED NORTHERLY
MID-LEVEL FLOW, IN ADDITION TO SURFACE HIGH PRESSURE FORECAST ACROSS THE DEEP
SOUTH FAVORING IDEAL RADIATIONAL COOLING CONDITIONS OVERNIGHT. ABOVE-NORMAL
TEMPERATURE PROBABILITIES REMAIN INCREASED ACROSS THE SOUTHERN FLORIDA
PENINSULA AND OVER PARTS OF THE NORTHEAST GIVEN THE SLOWER EASTWARD PROGRESSION
OF THE COLD FRONT AND ENHANCED SOUTHERLY MID-LEVEL FLOW AHEAD OF THE TROUGH
AXIS. THE 0Z GEFS ENSEMBLE BRINGS IN SOME TRANSIENT WARMING ACROSS PARTS OF THE
UPPER MIDWEST AND GREAT LAKES LATER IN THE PERIOD AS THE INITIAL TROUGH EXITS
AND THE MID-LEVEL FLOW TEMPORARILY BECOMES MORE ZONALLY ORIENTED AHEAD OF THE
NEXT TROUGH. THE MAGNITUDE OF THIS WARMING IS UNCERTAIN GIVEN WEAKER SIGNALS IN
THE 0Z ECMWF AND CANADIAN ENSEMBLES, RESULTING IN A FORECAST OF NEAR-NORMAL
TEMPERATURES ACROSS MUCH OF THE NORTHERN TIER. PROBABILITIES FOR ABOVE-NORMAL
TEMPERATURES ARE ELEVATED OVER MUCH OF THE WESTERN CONUS AND INTO ALASKA
UNDERNEATH RIDGING. ENHANCED OFFSHORE FLOW FAVORS A TILT TOWARD ENHANCED
BELOW-NORMAL TEMPERATURE PROBABILITIES ACROSS PARTS OF WESTERN AND NORTHERN
ALASKA. BELOW-NORMAL TEMPERATURE PROBABILITIES ARE ALSO INCREASED ACROSS HAWAII
UNDERNEATH TROUGHING AND NEGATIVE HEIGHT ANOMALIES, CONSISTENT WITH THE
CONSOLIDATED TEMPERATURE TOOL.
ABOVE-NORMAL PRECIPITATION PROBABILITIES ARE INCREASED ACROSS PARTS OF THE
SOUTHWEST, SOUTHERN PLAINS, CENTRAL GULF OF MEXICO COAST, AND SOUTHEAST NEAR
THE BASE OF THE PREDICTED TROUGH AXIS, AND WHERE A SLOW MOVING FRONT FAVORS ONE
OR MORE SHORTWAVE DISTURBANCES ENHANCING PRECIPITATION CHANCES ACROSS THESE
AREAS. BEHIND THE FRONT, AND UNDER ANOMALOUS NORTHERLY MID-LEVEL FLOW,
BELOW-NORMAL PRECIPITATION PROBABILITIES ARE INCREASED OVER MUCH OF THE GREAT
PLAINS, MIDWEST, AND PARTS OF THE MID-ATLANTIC AND NORTHEAST. LINGERING
PRECIPITATION CHANCES EARLY IN THE PERIOD ACROSS NEW ENGLAND FAVOR A TILT
TOWARD ENHANCED PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION FOR THE PERIOD AS
A WHOLE, SUPPORTED BY THE GEFS AND ECMWF REFORECAST TOOLS. RIDGING PREDICTED
ACROSS THE WEST FAVORS ENHANCED CHANCES OF BELOW-NORMAL PRECIPITATION ALONG THE
PACIFIC COAST EXTENDING INTO PARTS OF THE CENTRAL ROCKIES. TROUGHING RELOADING
LATER IN THE PERIOD SLIGHTLY ELEVATES ABOVE-NORMAL PRECIPITATION CHANCES ACROSS
THE NORTHERN ROCKIES. RIDGING BUILDING ACROSS THE NORTHEASTERN PACIFIC FAVORS A
NORTHWARD ORIENTED STORM TRACK ACROSS ALASKA, WITH ABOVE (BELOW)-NORMAL
PRECIPITATION PROBABILITIES INCREASED OVER MUCH OF THE MAINLAND AND ALEUTIANS
(SOUTHEAST ALASKA). NEAR- TO BELOW-NORMAL PRECIPITATION CHANCES ARE INCREASED
ACROSS HAWAII CONSISTENT WITH A MORE NORTHERLY MID-LEVEL FLOW PATTERN ACROSS
THE STATE IN THE WAKE OF TROUGHING.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON
DAY 8, 30% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY'S OPERATIONAL 0Z ECMWF 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
VERY GOOD MODEL AGREEMENT, OFFSET BY A TRANSIENT MID-LEVEL HEIGHT PATTERN, AND
SOME MINOR DIFFERENCES IN THE FORECAST TOOLS.
8-14 DAY OUTLOOK FOR MAR 19 - 25 2024
VERY GOOD MODEL AGREEMENT CONTINUES INTO WEEK-2, WITH THE 0Z ECMWF, GEFS, AND
CANADIAN ENSEMBLES ALL DEPICTING ANOMALOUS TROUGHING BUILDING INTO THE CENTRAL
CONUS EARLY IN THE PERIOD. THIS TROUGH IS FAVORED TO BE ORIENTED MORE TO THE
WEST COMPARED TO THE INITIAL TROUGH IN THE 6-10 DAY PERIOD, ALLOWING FOR SOME
WEAK RIDGING TO DEVELOP ACROSS NORTHEASTERN NORTH AMERICA BY THE MIDDLE OF THE
PERIOD. RIDGING IS ALSO PREDICTED ACROSS THE EASTERN PACIFIC, EXTENDING
NORTHWARD THROUGH ALASKA. THE WEEK-2 500-HPA MANUAL HEIGHT BLEND DEPICTS
BELOW-NORMAL HEIGHTS ACROSS MUCH OF THE EASTERN AND NORTHERN CONUS, AND
NEAR-NORMAL HEIGHTS OVER MUCH OF THE INTERIOR WEST GIVEN THE RETROGRESSION OF
RIDGING AND MORE INFLUENCE FROM TROUGHING. SLIGHTLY ABOVE-NORMAL HEIGHTS ARE
INDICATED ACROSS THE PACIFIC NORTHWEST, IN CLOSER PROXIMITY TO THE RIDGE OVER
THE PACIFIC. ABOVE-NORMAL HEIGHTS ARE PREDICTED FOR MUCH OF ALASKA, EXCLUDING
THE WESTERN ALEUTIANS WHERE UPSTREAM TROUGHING FAVORS A TRANSITION TO
BELOW-NORMAL HEIGHTS. BELOW-NORMAL HEIGHTS REMAIN FORECAST ACROSS HAWAII.
INCREASED BELOW-NORMAL TEMPERATURE PROBABILITIES ARE FORECAST ACROSS MUCH OF
THE EASTERN CONUS AND OVER PARTS OF THE NORTHERN ROCKIES AND PLAINS, WITH THE
EXCEPTIONS CONTINUING TO BE PARTS OF SOUTH FLORIDA AND NEW ENGLAND WHERE WEAK
PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES REMAIN FAVORED. AS IN THE 6-10 DAY
PERIOD, THERE IS UNCERTAINTY IN THE AMOUNT OF WARMING ACROSS PARTS OF THE
NORTHERN TIER OF THE CONUS, WITH THE GEFS REFORECAST TOOL DEPICTING
CONSIDERABLY HIGHER ABOVE-NORMAL TEMPERURARE PROBABILITIES COMPARED TO THE
ECMWF AND CANADIAN REFORECAST TOOLS. AS EVIDENCED BY THE ANALOGUE GUIDANCE, THE
TROUGH FORECAST TO AMPLIFY ACROSS THE CENTRAL CONUS FAVORS INCREASED CHANCES OF
BELOW-NORMAL TEMPERATURES, AND THIS TILT IS REFLECTED IN THE FORECAST DESPITE
SOME INITIAL WARMING POSSIBLE EARLY IN THE PERIOD. ACROSS THE WEST,
PROBABILITIES FOR NEAR- TO ABOVE-NORMAL TEMPERATURES ARE INCREASED OVER MOST
AREAS, ALTHOUGH THERE ARE SOME DIFFERENCES BETWEEN THE UNCALIBRATED GUIDANCE
AND REFORECAST TOOLS OVER THE INTERIOR WEST AS RIDGING BECOMES MORE FOCUSED
ACROSS THE PACIFIC AND HEIGHT ANOMALIES BECOME NEGATIVE, RESULTING IN A GREATER
TILT TOWARD NEAR-NORMAL TEMPERATURES OVER PARTS OF THE ROCKIES AND HIGH PLAINS.
HIGH PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE FORECAST ACROSS ALASKA
GIVEN THE RIDGE PLACEMENT, CONSISTENT WITH NEARLY ALL DYNAMICAL AND STATISTICAL
GUIDANCE. BELOW-NORMAL TEMPERATURES REMAIN FORECAST ACROSS HAWAII, SUPPORTED BY
THE CONSOLIDATED FORECAST TOOL.
THE TRANSITION TO MORE TROUGHING ACROSS THE CENTRAL CONUS RESULTS IN A BROAD
AREA OF ELEVATED NEAR- TO ABOVE-NORMAL PRECIPITATION PROBABILITIES ACROSS MOST
OF THE CONUS, EXCLUDING THE PACIFIC NORTHWEST WHERE BELOW-NORMAL PRECIPITATION
PROBABILITIES ARE ENHANCED CLOSER TO THE RIDGING OVER THE EASTERN PACIFIC.
MODELS DO NOT CLEARLY INDICATE ANY MAJOR STORM SYSTEMS, BUT THE SYNOPTIC
PATTERN FAVORS A STORM TRACK THROUGH THE GREAT LAKES LEADING TO AN ENHANCEMENT
OF PROBABILITIES IN THAT REGION, WITH OCCASIONAL FRONTALLY FOCUSED
PRECIPITATION ACROSS PARTS OF THE EAST. AS IN THE 6-10 DAY OUTLOOK, RIDGING
OVER THE EASTERN PACIFIC FAVORS A NORTHWARD ORIENTED STORM TRACK ACROSS ALASKA
RESULTING IN ENHANCED PROBABILITIES FOR ABOVE-NORMAL PRECIPITATION OVER MUCH OF
THE MAINLAND AND ALEUTIANS, AND INCREASED CHANCES FOR BELOW-NORMAL
PRECIPITATION ACROSS SOUTHEAST ALASKA. BELOW-NORMAL PRECIPITATION IS FAVORED
FOR HAWAII, AS MEAN TROUGHING SHIFTS FAR ENOUGH TO THE EAST.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 6Z 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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT REGARDING THE MID-LEVEL PATTERN EVOLUTION, OFFSET BY
WEAKENING SYNOPTIC SIGNALS LATER IN THE PERIOD.
FORECASTER: THOMAS COLLOW
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
MARCH 21.
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:
19730316 - 19530315 - 19770305 - 19990309 - 19900307
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:
19530314 - 19770308 - 19730317 - 19900307 - 19990310
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 17 - 21 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A B
SRN CALIF A B IDAHO A B NEVADA A B
W MONTANA A A E MONTANA A N WYOMING A N
UTAH A N ARIZONA A A COLORADO N N
NEW MEXICO B A N DAKOTA N B S DAKOTA N B
NEBRASKA N B KANSAS N B OKLAHOMA B B
N TEXAS B N S TEXAS B A W TEXAS B A
MINNESOTA N B IOWA N B MISSOURI B B
ARKANSAS B B LOUISIANA B A WISCONSIN N B
ILLINOIS B B MISSISSIPPI B N MICHIGAN N B
INDIANA B B OHIO B B KENTUCKY B B
TENNESSEE B B ALABAMA B A NEW YORK N N
VERMONT A N NEW HAMP A N MAINE A A
MASS A N CONN A N RHODE IS A N
PENN N B NEW JERSEY N N W VIRGINIA B B
MARYLAND N B DELAWARE N N VIRGINIA N B
N CAROLINA N N S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN N A AK N SLOPE B A
AK ALEUTIAN A A AK WESTERN A A AK INT BSN A A
AK S INT A A AK SO COAST A A AK PNHDL A B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 19 - 25 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A N NRN CALIF A N
SRN CALIF A A IDAHO A A NEVADA A A
W MONTANA N A E MONTANA B A WYOMING N A
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO N A N DAKOTA B A S DAKOTA N A
NEBRASKA N A KANSAS N A OKLAHOMA N N
N TEXAS B N S TEXAS B N W TEXAS N N
MINNESOTA B A IOWA N A MISSOURI B A
ARKANSAS B N LOUISIANA B A WISCONSIN B A
ILLINOIS B A MISSISSIPPI B A MICHIGAN N A
INDIANA B A OHIO B A KENTUCKY B A
TENNESSEE B A ALABAMA B A NEW YORK N A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN N A RHODE IS N N
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 B A
FL PNHDL B A FL PENIN B A AK N SLOPE A A
AK ALEUTIAN A A AK WESTERN A A AK INT BSN A A
AK S INT A A AK SO COAST A A AK PNHDL A B
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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