899
FXUS06 KWBC 232003
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI FEBRUARY 23 2024
6-10 DAY OUTLOOK FOR FEB 29 - MAR 04, 2024
TODAY’S DYNAMICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED
MID-LEVEL MEAN HEIGHT PATTERN OVER THE FORECAST DOMAIN DURING THE 6-10 DAY
PERIOD. THE SIGNIFICANT DAY-TO-DAY DIFFERENCES IN MODEL DETAILS NOTED OVER THE
LAST FEW DAYS HAVE LARGELY DISAPPEARED. THE LATEST ENSEMBLE MEAN HEIGHT
FORECASTS DEPICT A POSITIVE HEIGHT ANOMALY CENTER SOUTH OF THE ALEUTIANS IN THE
VICINITY OF 40N/165-170W (ABOUT 165 METERS ABOVE NORMAL ON THE MANUAL HEIGHT
BLEND), ASSOCIATED WITH AN ANOMALOUS MID-LEVEL RIDGE THAT EXTENDS NORTHWARD
OVER THE BERING SEA AND FAR EASTERN SIBERIA. THIS RIDGE SHOWS SIGNS OF
WEAKENING BY THE MIDDLE OF THE PERIOD, WITH THE 0Z EUROPEAN ENSEMBLE MEAN
(ECENS) RETAINING THE MOST AMPLIFIED AND PERSISTENT RIDGE. DOWNSTREAM, A
MID-LEVEL TROUGH AND WELL BELOW-NORMAL 500-HPA HEIGHTS ARE PREDICTED FROM MUCH
OF ALASKA SOUTHEASTWARD ACROSS THE FAR EASTERN PACIFIC AND NORTHWESTERN
CONTIGUOUS U.S. (CONUS). THE LARGEST NEGATIVE HEIGHT ANOMALIES (ABOUT 195
METERS BELOW NORMAL ON THE MANUAL HEIGHT BLEND) ARE DEPICTED FROM SOUTHEAST
ALASKA TO VANCOUVER ISLAND. BY DAY 9, THE MODELS FORECAST A RELOADING OF THE
ALASKA TROUGH FARTHER WEST. OVER THE CENTRAL AND EASTERN CONUS AND ADJACENT
SOUTHEASTERN CANADA, WELL ABOVE-NORMAL 500-HPA HEIGHTS ARE FORECAST, ASSOCIATED
WITH LOW AMPLITUDE FLOW. THE MANUAL HEIGHT BLEND DEPICTS A MAXIMUM POSITIVE
HEIGHT ANOMALY NEAR +210 METERS OVER NEW ENGLAND.
THE 6-10 DAY TEMPERATURE OUTLOOK FAVORS INCREASED CHANCES FOR ABOVE-NORMAL
TEMPERATURES FROM APPROXIMATELY THE NORTHERN HIGH PLAINS AND EASTERN
INTERMOUNTAIN REGION EASTWARD ACROSS THE CENTRAL AND EASTERN CONUS, WITH
HIGHEST PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES EXCEEDING 80 PERCENT FROM
THE VICINITY OF THE UPPER MISSISSIPPI VALLEY EASTWARD INTO THE LOWER GREAT
LAKES REGION. THIS IS CONSISTENT WITH THE STATISTICAL TEMPERATURE ANALOGS
DERIVED FROM THE MANUAL HEIGHT BLEND. BELOW-NORMAL TEMPERATURE CHANCES ARE
ELEVATED ACROSS THE FAR WEST IN PROXIMITY TO A MID-LEVEL TROUGH AND
BELOW-NORMAL HEIGHTS, AND CONSISTENT WITH RAW (UNCALIBRATED) MODEL TEMPERATURES
FROM THE ENSEMBLE MEANS. TODAY’S 6-10 DAY TEMPERATURE OUTLOOK REFLECTS A
COMPROMISE BETWEEN THE COOLER RAW MODEL TEMPERATURE FORECASTS AND THE WARMER
REFORECAST-CALIBRATED TEMPERATURES OVER THE WESTERN CONUS. ACROSS ALASKA,
SURFACE TEMPERATURE TOOLS ARE IN UNANIMOUS AGREEMENT FAVORING INCREASED CHANCES
FOR BELOW-NORMAL TEMPERATURES, WITH PROBABILITIES EXCEEDING 90 PERCENT OVER
SOUTH-CENTRAL ALASKA. THE EXCEPTION INCLUDES THE WESTERN ALEUTIANS, WHERE
ABOVE-NORMAL TEMPERATURES ARE FAVORED. THIS SCENARIO IS ALSO CONSISTENT WITH
THE PREDICTED MANUAL HEIGHT BLEND. FOR HAWAII, NEAR TO ABOVE-NORMAL
TEMPERATURES ARE FAVORED, REPRESENTING A COMPROMISE BETWEEN THE AUTOMATED AND
CONSOLIDATED TEMPERATURE TOOLS.
THE 6-10 DAY PRECIPITATION OUTLOOK FAVORS INCREASED ODDS FOR ABOVE-NORMAL
PRECIPITATION OVER THE VAST MAJORITY OF THE LOWER 48 STATES. WEST OF THE
CONTINENTAL DIVIDE, THIS IS ATTRIBUTED TO THE PROXIMITY OF A STRONG MID-LEVEL
TROUGH AND MOIST, ONSHORE FLOW SOUTH OF SURFACE LOW PRESSURE OFF THE COAST OF
SOUTHEAST ALASKA. CHANCES FOR WETTER-THAN-NORMAL CONDITIONS EXCEED 70 PERCENT
IN FAR NORTHWESTERN CALIFORNIA. EAST OF THE DIVIDE, THERE ARE TWO MAJOR FACTORS
TO CONSIDER. DURING THE FIRST HALF OF THE PERIOD, AN INCREASE IN SOUTHERLY
RETURN FLOW OF MOIST AIR FROM THE GULF OF MEXICO IS EXPECTED ACROSS THE
SOUTHEAST, AND A COLD FRONT IS FORECAST TO MOVE ACROSS THE NORTHEAST AND OFF
THE COAST. THIS RESULTS IN ENHANCED CHANCES OF ABOVE-NORMAL AND NEAR-NORMAL
PRECIPITATION, RESPECTIVELY. ON DAY 9, THE MODELS ANTICIPATE LEE CYCLOGENESIS
OVER THE CENTRAL HIGH PLAINS, WITH THE STORM CENTER SUBSEQUENTLY TRACKING
TOWARDS THE GREAT LAKES. THIS INCREASES THE ODDS FOR ABOVE-NORMAL PRECIPITATION
ACROSS THE CENTRAL AND EAST-CENTRAL STATES. THE PRECIPITATION OUTLOOK ACROSS
THE FOUR CORNERS AREA CONTINUES ITS TENDENCY TO VACILLATE OVER THE PAST FEW
DAYS, WITH INCREASED PRECIPITATION AGAIN EXPECTED TO MOVE THROUGH THE REGION
ASSOCIATED WITH A SURGE OF PACIFIC MOISTURE ASSOCIATED WITH AN ADVANCING
MID-LEVEL TROUGH. FOR ALASKA, A MID-LEVEL TROUGH PREDICTED OVER EASTERN
PORTIONS OF THE STATE FAVORS NEAR TO BELOW-NORMAL PRECIPITATION ACROSS THE
NORTHERN, CENTRAL, AND SOUTHWESTERN MAINLAND, AND THE ALASKA PENINSULA. FOR
SOUTHEAST ALASKA, NEAR TO ABOVE-NORMAL PRECIPITATION IS FAVORED, CLOSER TO THE
SURFACE LOW PRESSURE TROUGH ANTICIPATED JUST OFF THE COAST. THE HAWAIIAN
PRECIPITATION OUTLOOK FAVORS MOSTLY ABOVE-NORMAL PRECIPITATION, SUPPORTED BY
THE AUTOMATED AND CONSOLIDATED PRECIPITATION TOOLS.
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, GIVEN
GOOD AGREEMENT IN THE MEAN HEIGHT AND TEMPERATURE FIELDS, OFFSET BY SUBSTANTIAL
DIFFERENCES AMONG THE PRECIPITATION TOOLS ESPECIALLY ACROSS THE NORTHEAST.
8-14 DAY OUTLOOK FOR MAR 02 - 08 2024
FOR WEEK-2, THE VARIOUS ENSEMBLE MEAN SOLUTIONS DEPICT A MEAN MID-LEVEL
CIRCULATION PATTERN THAT IS SIMILAR TO THE ONE PREDICTED FOR THE EARLIER 6-10
DAY PERIOD. THE THREE PRIMARY LONGWAVE FEATURES EXPECTED TO AFFECT NORTH
AMERICA INCLUDE LARGE ANOMALOUS RIDGES CENTERED OVER THE NORTH-CENTRAL PACIFIC
(40N, 170-180W) AND IN THE VICINITY OF MAINE. A SIGNIFICANT ANOMALOUS TROUGH IS
FAVORED FROM ALASKA SOUTHEASTWARD OVER PORTIONS OF THE WESTERN CONUS. THE 0Z
GEFS PREDICTS AT LEAST -30 METER HEIGHT DEPARTURES ACROSS APPROXIMATELY THE
WESTERN HALF OF THE CONUS, WHILE THE 0Z ECENS DEPICTS AT LEAST -30 METER HEIGHT
DEPARTURES ENCLOSING ONLY THE NORTHWESTERN CONUS. THE MANUAL HEIGHT BLEND
DEPICTS BROAD BUT WEAK CYCLONIC CURVATURE ACROSS THE WESTERN AND CENTRAL THIRDS
OF THE LOWER 48 STATES, AND ANTICYCLONIC CURVATURE OVER THE EASTERN THIRD OF
THE CONUS.
THE WEEK-2 TEMPERATURE OUTLOOK FAVORS BELOW-NORMAL TEMPERATURE CHANCES FOR MOST
OF THE WESTERN THIRD OF THE CONUS. SIMILAR TO WHAT WAS DONE FOR THE 6-10 DAY
TEMPERATURE OUTLOOK, THE WEEK-2 TEMPERATURE OUTLOOK REPRESENTS A COMPROMISE
BETWEEN COOLER RAW MODEL TEMPERATURES AND WARMER REFORECAST-CALIBRATED
TEMPERATURES. THIS IS ALSO CONSISTENT WITH A MID-LEVEL TROUGH AND BELOW-NORMAL
HEIGHTS PREDICTED ACROSS THIS REGION. FROM APPROXIMATELY THE ROCKIES EASTWARD
ACROSS THE CENTRAL AND EASTERN CONUS, ODDS FAVOR ABOVE-NORMAL TEMPERATURES,
WITH 80 PERCENT OR BETTER CHANCES INDICATED FROM THE GREAT LAKES REGION AND
NORTHERN OHIO VALLEY EASTWARD TO THE NORTHERN AND UPPER MID-ATLANTIC COAST.
THIS IS CONSISTENT WITH THE FORECAST OF MID-LEVEL ANOMALOUS RIDGING, AND MOST
OF TODAY’S WEEK-2 TEMPERATURE GUIDANCE. IN ALASKA, TOOLS CONTINUE TO FAVOR
BELOW-NORMAL TEMPERATURES STATE-WIDE INCLUDING THE WESTERN ALEUTIANS. THIS
LATTER AREA IS NEAR THE PREDICTED LOCATION OF THE RELOADING MID-LEVEL TROUGH
EARLY IN WEEK-2, AND WHERE REINFORCING COLD AIR IS EXPECTED TO TRAVERSE.
FARTHER SOUTH IN HAWAII, NEAR-NORMAL TEMPERATURES ARE FAVORED FOR THE CENTRAL
AND SOUTHEASTERN ISLANDS, AND ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER THE
NORTHWESTERN ISLANDS OF OAHU, KAUAI, AND NIIHAU. THIS REPRESENTS A COMPROMISE
BETWEEN AUTOMATED AND CONSOLIDATED TEMPERATURE TOOLS.
AS WAS THE CASE FOR THE EARLIER 6-10 DAY PRECIPITATION OUTLOOK, THE WEEK-2
PRECIPITATION OUTLOOK FAVORS INCREASED CHANCES OF ABOVE-NORMAL PRECIPITATION
ACROSS NEARLY ALL OF THE LOWER 48 STATES. IN THE WEST, THIS IS DUE TO THE
PROXIMITY OF A SIGNIFICANT MID-LEVEL TROUGH AND MOIST, ONSHORE FLOW ASSOCIATED
WITH AN AREA OF SURFACE LOW PRESSURE OFF THE COASTS OF SOUTH-CENTRAL AND
SOUTHEAST ALASKA. ABOVE-NORMAL PRECIPITATION CHANCES ARE THEREFORE ELEVATED
ACROSS SOUTH-CENTRAL AND SOUTHEAST ALASKA, AND ALSO OVER THE ALEUTIANS.
BELOW-NORMAL PRECIPITATION CHANCES ARE INCREASED OVER WESTERN PORTIONS OF
MAINLAND ALASKA, SUPPORTED TO VARYING DEGREES BY THE REFORECAST PRECIPITATION
TOOLS. RETURNING TO THE LOWER 48 STATES, A MINIMAL TILT IN THE ODDS FAVORING
ABOVE-NORMAL PRECIPITATION IS DEPICTED OVER PORTIONS OF THE INTERMOUNTAIN WEST,
THE ROCKIES, AND WESTERN AND SOUTHERN TEXAS. THIS IS CONSISTENT WITH INCREASED
SOUTHERLY RETURN FLOW FROM THE GULF OF MEXICO EARLY IN WEEK-2, FOLLOWED BY A
CYCLONIC SYSTEM EXPECTED TO TRACK FROM THE CENTRAL HIGH PLAINS NORTHEASTWARD
ACROSS THE GREAT LAKES REGION WITH ITS ACCOMPANYING FRONTAL ZONES.
PRECIPITATION IS FORECAST TO TAPER OFF FARTHER EAST OVER THE NORTHEAST AND
MID-ATLANTIC REGIONS, CLOSER TO THE LARGEST POSITIVE 500-HPA HEIGHT ANOMALIES
CENTERED IN THE VICINITY OF MAINE. ABOVE-NORMAL PRECIPITATION CHANCES ARE
ENHANCED ACROSS MOST OF HAWAII AS DEPICTED BY THE AUTOMATED AND CONSOLIDATED
PRECIPITATION TOOLS.
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 OVERALL AGREEMENT AMONG THE FORECASTED MID-LEVEL HEIGHT PATTERNS AND
SURFACE TEMPERATURE PATTERNS, OFFSET BY UNCERTAINTY IN THE TEMPERATURE PATTERN
OVER THE WEST-CENTRAL CONUS AS NOTED EARLIER, AND SOME UNCERTAINTY AMONG 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
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:
20090217 - 19900302 - 19850308 - 19590217 - 20060218
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:
20090303 - 19900302 - 19850307 - 20090216 - 20010214
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 29 - MAR 04, 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B A
SRN CALIF B A IDAHO N A NEVADA B A
W MONTANA N A E MONTANA A A WYOMING A A
UTAH A A ARIZONA A N COLORADO A N
NEW MEXICO A N N DAKOTA A A 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 A A IOWA A A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN A A
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK A A
VERMONT A N NEW HAMP A N MAINE A N
MASS A N CONN A A RHODE IS A N
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 A AK N SLOPE B N
AK ALEUTIAN B N AK WESTERN B B AK INT BSN B B
AK S INT B N AK SO COAST B N AK PNHDL B A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 02 - 08 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B A
SRN CALIF B A IDAHO B A NEVADA B A
W MONTANA B A E MONTANA A A WYOMING N A
UTAH B A ARIZONA B A COLORADO N A
NEW MEXICO N A N DAKOTA A A 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 A A IOWA A A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN A A
ILLINOIS A A MISSISSIPPI A A MICHIGAN A A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK A A
VERMONT A A NEW HAMP A A MAINE A N
MASS A N CONN A N RHODE IS A N
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 A AK N SLOPE B N
AK ALEUTIAN B N AK WESTERN B B AK INT BSN B N
AK S INT B A AK SO COAST B A AK PNHDL B 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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