763
FXUS06 KWBC 182002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE FEBRUARY 18 2025
6-10 DAY OUTLOOK FOR FEB 24 - 28 2025
A PROGRESSIVE FLOW PATTERN IS FORECAST TO TAKE SHAPE ACROSS NORTH AMERICA
DURING THE 6-10 DAY PERIOD AS THE ARCTIC OSCILLATION (AO) BECOMES POSITIVE
DURING THE LAST WEEK OF FEBRUARY. HOWEVER, THE MEAN MID-LEVEL HEIGHT PATTERN IS
PREDICTED TO REMAIN BROADLY AMPLIFIED, WITH RIDGING AND ABOVE-NORMAL HEIGHTS
FAVORED ACROSS THE WESTERN CONUS, AND TROUGHING AND BELOW-NORMAL HEIGHTS ACROSS
THE EAST. THE 0Z ECENS IS LESS ROBUST WITH THE TROUGHING IN THE EAST COMPARED
TO THE 0Z GEFS AROUND THE MIDDLE OF THE PERIOD, BUT THERE IS BETTER MODEL
AGREEMENT TOWARD DAY-10 (FEB 28) AS A MID-LEVEL LOW SHIFTS SOUTHEASTWARD FROM
THE ARCTIC INTO NORTHEASTERN CANADA LEADING TO DECREASING HEIGHTS OVER THE
EAST. TROUGHING IS INITIALLY FORECAST ACROSS ALASKA, BUT THIS FEATURE IS
FORECAST TO WEAKEN WITH TIME, WITH MORE RIDGING BUILDING INTO SOUTHEAST AND
EASTERN MAINLAND ALASKA BY THE END OF THE PERIOD. BELOW-NORMAL HEIGHTS ARE
FAVORED OVER MUCH OF WESTERN AND SOUTHERN MAINLAND ALASKA, WITH CLOSER TO
NORMAL HEIGHTS FORECAST ACROSS SOUTHEAST AND NORTHERN MAINLAND ALASKA TIED TO
THE FORECAST MID-LEVEL PATTERN TRANSITION.
ELEVATED PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE FAVORED ACROSS MUCH OF
THE WESTERN AND CENTRAL CONUS TIED TO RIDGING AND CONSISTENT WITH THE GEFS AND
ECENS REFORECAST TOOLS. THE HIGHEST PROBABILITIES (GREATER THAN 80 PERCENT) ARE
HIGHLIGHTED ACROSS THE SOUTHWEST AND THE NORTHERN PLAINS. THE ECENS REFORECAST
TOOL IS NOTABLY WARMER ACROSS PARTS OF THE NORTHEAST COMPARED TO ITS GEFS
COUNTERPART, AND THIS IS LIKELY DUE TO THE WEAKER TROUGHING DEPICTED IN THE 0Z
ECENS. HOWEVER, TELECONNECTION ANALYSIS WITH THE NEGATIVE MID-LEVEL HEIGHT
ANOMALY CENTER OVER NORTHEAST CANADA SUPPORTS BELOW-NORMAL TEMPERATURES OVER
THE NORTHEAST. WHILE ALL MODELS INDICATE SOME EVIDENCE OF A WARMING TREND EARLY
IN THE PERIOD, THEY TREND COLDER BY DAY-10 (FEB 28), PARTICULARLY THE GEFS, AS
THE MID-LEVEL LOW OVER CANADA SHIFTS SOUTHEASTWARD. GIVEN THE DISCREPANCY IN
THE REFORECAST TOOLS AND SOME UNCERTAINTY IN THE MID-LEVEL PATTERN EVOLUTION,
NEAR-NORMAL TEMPERATURES ARE FAVORED ACROSS MUCH OF THE EAST. THE EXCEPTION IS
ACROSS PARTS OF THE SOUTHEAST WHERE BELOW-NORMAL TEMPERATURES PROBABILITIES ARE
INCREASED DUE TO BETTER AGREEMENT IN THE TOOLS. INCREASED CHANCES FOR
ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF ALASKA UNDERNEATH ENHANCED
SOUTHERLY FLOW UPSTREAM OF TROUGHING AND DUE TO INCREASING MID-LEVEL HEIGHTS
OVER EASTERN ALASKA LATER IN THE PERIOD. NEAR-NORMAL TEMPERATURES ARE PREDICTED
OVER PARTS OF THE WESTERN MAINLAND AND THE ALEUTIANS CLOSER TO THE TROUGH AXIS.
ABOVE-NORMAL TEMPERATURES ARE STRONGLY FAVORED ACROSS HAWAII.
RIDGING OVER THE WESTERN CONUS COMBINED WITH A MORE PROGRESSIVE FLOW PATTERN
FAVORS ELEVATED PROBABILITIES FOR BELOW-NORMAL PRECIPITATION OVER MUCH OF THE
CENTRAL AND SOUTHERN TIERS OF THE CONUS. THERE IS GOOD AGREEMENT IN THE MODELS
REGARDING A LESS ACTIVE STROM TRACK DURING THIS PERIOD COMPARED TO EARLIER IN
THE MONTH WITH SURFACE HIGH PRESSURE EXTENDING FROM THE WESTERN CONUS INTO THE
MID-SOUTH. THE GEFS AND ECENS REFORECAST TOOLS SUPPORT A TILT TOWARD ENHANCED
ABOVE-NORMAL PRECIPITATION PROBABILITIES ALONG PARTS OF THE U.S./CANADIAN
BORDER, WITH NEAR-NORMAL PRECIPITATION CHANCES EXTENDING FURTHER SOUTH ALONG
THE EASTERN SEABOARD GIVEN THE DEPICTION OF SURFACE LOW DEVELOPMENT AND
ASSOCIATED ENHANCED PRECIPITATION ALONG THE EAST COAST IN THE 0Z ECENS AND
RECENT DETERMINISTIC GFS RUNS ON DAYS 9 AND 10 (FEB 27-28). ABOVE-NORMAL
PRECIPITATION CHANCES ARE INCREASED ACROSS SOUTHEASTERN ALASKA TIED TO AN
ACTIVE SURFACE LOW TRACK OVER THE NORTH-CENTRAL PACIFIC. NEAR-NORMAL
PRECIPITATION IS FORECAST ACROSS THE ALEUTIANS AND NORTHERN MAINLAND FURTHER
DISPLACED FROM THE MEAN STORM TRACK. NEAR- TO BELOW-NORMAL PRECIPITATION IS
FORECAST ACROSS HAWAII SUPPORTED BY THE REFORECAST CONSOLIDATION TOOL.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% 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
GENERALLY GOOD AGREEMENT IN THE FORECAST TOOLS REGARDING TEMPERATURE AND
PRECIPITATION PROBABILITIES, OFFSET BY SOME UNCERTAINTY DUE TO A MORE
PROGRESSIVE MID-LEVEL FLOW PATTERN AND THE DEGREE OF TROUGHING IN THE EAST.
8-14 DAY OUTLOOK FOR FEB 26 - MAR 04, 2025
DURING WEEK-2, THE 500-HPA HEIGHT PATTERN ACROSS WESTERN NORTH AMERICA IS
FORECAST TO WEAKEN AND RETROGRADE, WITH A VARIABLE HEIGHT PATTERN CONTINUING
ACROSS THE EAST, ALTHOUGH WITH A TENDENCY TOWARD MORE TROUGHING AS MID-LEVEL
LOW PRESSURE BECOMES CENTERED ACROSS ATLANTIC CANADA. BY THE END OF THE PERIOD,
TROUGHING MAY ALSO INCREASE ACROSS PORTIONS OF THE WEST-CENTRAL CONUS AS THE
RIDGING SHIFTS FURTHER UPSTREAM. FOR THE PERIOD AS A WHOLE, NEAR-NORMAL HEIGHTS
ARE FAVORED ACROSS MUCH OF THE EASTERN HALF OF THE CONUS. ABOVE-NORMAL HEIGHTS
ARE FORECAST ACROSS THE WESTERN CONUS, ALTHOUGH THE POSITIVE ANOMALIES ARE
SUBSTANTIALLY REDUCED COMPARED TO THE 6-10 DAY PERIOD. THE RETROGRESSION OF THE
TROUGH-RIDGE PATTERN SUPPORTS BELOW-NORMAL HEIGHTS ACROSS FAR WESTERN MAINLAND
ALASKA AND THE ALEUTIANS, WITH ABOVE-NORMAL HEIGHTS OVER EASTERN ALASKA.
THE GEFS AND ECENS REFORECAST TOOLS CONTINUE TO SUPPORT INCREASED PROBABILITIES
FOR ABOVE-NORMAL TEMPERATURES ACROSS THE WESTERN AND CENTRAL CONUS TIED TO
RIDGING EARLY IN THE PERIOD. THE TEMPERATURE FORECAST IS MORE UNCERTAIN ACROSS
THE EAST, WITH THE GEFS (ECENS) REFORECAST TOOL DEPICTING ENHANCED CHANCES FOR
BELOW (ABOVE) NORMAL TEMPERATURES. TODAY’S OUTLOOK LEANS TOWARD HIGHER CHANCES
OF NEAR- TO BELOW-NORMAL TEMPERATURES GIVEN THE PROJECTED EXTENSION OF NEGATIVE
HEIGHT ANOMALIES OVER NORTHEASTERN CANADA THROUGHOUT THE PERIOD, ALONG WITH
SUPPORT FROM UNCALIBRATED GUIDANCE AND THE TELECONNECTION TOOL. ABOVE-NORMAL
TEMPERATURE PROBABILITIES ARE INCREASED OVER MOST OF ALASKA AS RIDGING BUILDS
ACROSS THE STATE. ABOVE-NORMAL TEMPERATURES ALSO REMAIN FAVORED ACROSS HAWAII.
THE LARGEST SHIFT RELATIVE TO THE 6-10 DAY PERIOD IS IN THE PRECIPITATION
FORECAST ACROSS THE CONUS. AS THE RIDGING INITIALLY OVER THE WEST RETROGRADES,
WITH A MORE CYCLONIC MID-LEVEL FLOW PATTERN IN ITS WAKE, A MORE ACTIVE STORM
TRACK MAY BEGIN TO DEVELOP ACROSS THE CENTRAL CONUS BY THE END OF WEEK-2.
FORECAST TOOLS SUPPORT ENHANCED CHANCES FOR ABOVE-NORMAL PRECIPITATION ACROSS
MUCH OF THE CENTRAL CONUS, WITH A HIGHER CLIMATOLOGY RESULTING IN NEAR-NORMAL
PRECIPITATION FAVORED FOR MUCH OF THE EAST. CONVERSELY, BELOW-NORMAL
PRECIPITATION PROBABILITIES ARE INCREASED CLOSER TO THE WEST COAST TIED TO
DECREASED ONSHORE FLOW AS THE RIDGING BECOMES CENTERED OVER THE EASTERN
PACIFIC. ENHANCED CHANCES FOR ABOVE-NORMAL PRECIPITATION REMAIN FAVORED FOR
MOST OF ALASKA UNDERNEATH ENHANCED SOUTHERLY FLOW AND AN ACTIVE STORM TRACK,
ESPECIALLY EARLY IN THE PERIOD. NEAR-TO BELOW NORMAL PRECIPITATION REMAINS
FAVORED FOR MOST OF HAWAII. A SLIGHT TILT TOWARD ENHANCED ABOVE-NORMAL
PRECIPITATION ODDS IS FORECAST OVER KAUAI DUE TO SOME INFLUENCE FROM TROUGHING
EXTENDING ACROSS THE CENTRAL PACIFIC DURING THE PERIOD.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 25% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 50% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 25% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO
GENERALLY GOOD TOOL AGREEMENT, OFFSET BY SOME UNCERTAINTY DUE TO A
TRANSITIONING MID-LEVEL PATTERN AND IN THE TEMPERATURE FORECAST ACROSS THE EAST.
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
FEBRUARY 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:
20070212 - 19570304 - 19570217 - 19710204 - 19860207
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:
20070212 - 19570303 - 19710204 - 19800210 - 19570216
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 24 - 28 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A N NRN CALIF A B
SRN CALIF A B IDAHO A B NEVADA A B
W MONTANA A N E MONTANA A N WYOMING A B
UTAH A B ARIZONA A B COLORADO A B
NEW MEXICO A B N DAKOTA A A S DAKOTA A N
NEBRASKA A B KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA A A IOWA A B MISSOURI A B
ARKANSAS A B LOUISIANA A B WISCONSIN A N
ILLINOIS A B MISSISSIPPI N B MICHIGAN N N
INDIANA N B OHIO N N KENTUCKY N B
TENNESSEE N B ALABAMA N B NEW YORK N N
VERMONT N N NEW HAMP N N MAINE N A
MASS N N CONN N N RHODE IS N N
PENN N N NEW JERSEY N N W VIRGINIA N N
MARYLAND N N DELAWARE N N VIRGINIA N N
N CAROLINA N N S CAROLINA N N GEORGIA N B
FL PNHDL B B FL PENIN B N AK N SLOPE A N
AK ALEUTIAN A N AK WESTERN A N AK INT BSN A N
AK S INT A A AK SO COAST A A AK PNHDL A A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 26 - MAR 04, 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A B
SRN CALIF A N IDAHO A B NEVADA A B
W MONTANA A N E MONTANA A A WYOMING A A
UTAH A N ARIZONA A N COLORADO A A
NEW MEXICO A 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 N MISSISSIPPI N A MICHIGAN B N
INDIANA N N OHIO B N KENTUCKY N N
TENNESSEE N N ALABAMA N N NEW YORK B N
VERMONT B N NEW HAMP B N MAINE B N
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 N N S CAROLINA N N GEORGIA N N
FL PNHDL N N FL PENIN B N 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 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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