877
FXUS06 KWBC 132002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST MON JANUARY 13 2025
6-10 DAY OUTLOOK FOR JAN 19 - 23 2025
A HIGHLY AMPLIFIED 500-HPA HEIGHT PATTERN IS FORECAST ACROSS THE FORECAST
DOMAIN DURING THE 6-10 DAY PERIOD, WITH RIDGING OVER WESTERN NORTH AMERICA AND
STRONG TROUGHING DOWNSTREAM EAST OF THE ROCKIES. THE MANUAL HEIGHT BLEND
INDICATES ABOVE-NORMAL HEIGHTS WEST OF THE ROCKIES AND EXTENDING NORTHWARD
THROUGH ALASKA. A +210 METER POSITIVE HEIGHT ANOMALY CENTER IS NOTED JUST TO
THE WEST OF BRITISH COLUMBIA. BELOW NORMAL HEIGHTS ARE PREDICTED FOR MOST OF
THE CONUS EAST OF THE ROCKIES, WITH THE STRONGEST NEGATIVE ANOMALIES (-180
METERS) OVER THE GREAT LAKES. SLIGHTLY ABOVE-NORMAL HEIGHTS ARE FORECAST ACROSS
THE FLORIDA PENINSULA, FURTHER DOWNSTREAM FROM THE MEAN TROUGH AXIS. A VARIABLE
MID-LEVEL HEIGHT PATTERN IS FORECAST ACROSS THE CENTRAL PACIFIC AND HAWAII,
ALTHOUGH MORE TROUGHING MAY BEGIN TO TAKE SHAPE LATER IN THE PERIOD.
NEAR-NORMAL HEIGHTS ARE FORECAST ACROSS THE ISLANDS FOR THE PERIOD AS A WHOLE.
THE DEEP TROUGHING MOVING THROUGH THE CENTRAL AND EASTERN CONUS IS LIKELY TO
LEAD TO A MAJOR ARCTIC AIR OUTBREAK. THE 0Z ECENS INDICATES WIDESPREAD DAILY
TEMPERATURE ANOMALIES EXCEEDING -20 DEG F, ESPECIALLY EARLY IN THE PERIOD,
CORRESPONDING WITH SUBZERO TEMPERATURES ACROSS THE NORTHERN AND CENTRAL PLAINS,
MIDWEST, AND POSSIBLY INTO THE INTERIOR NORTHEAST, AND MINIMUM TEMPERATURES IN
THE 20S DEG F POSSIBLY REACHING THE GULF OF MEXICO COAST. THE 0Z GEFS IS NOT AS
COLD AS THE ECENS, BUT STILL IS IN GOOD AGREEMENT REGARDING THE PATTERN AND
PLACEMENT OF BELOW-NORMAL TEMPERATURES. THE REFORECAST AND UNCALIBRATED TOOLS
ALL SUPPORT ELEVATED PROBABILITIES FOR BELOW-NORMAL TEMPERATURES ACROSS NEARLY
ALL OF THE CONUS, WITH THE HIGHEST CHANCES (GREATER THAN 80 PERCENT) ACROSS THE
GREAT PLAINS EAST TO THE APPALACHIANS. INCREASING DOWNSLOPE WINDS SLIGHTLY
FAVOR NEAR- TO ABOVE-NORMAL TEMPERATURES ACROSS PORTIONS OF CALIFORNIA AND
WESTERN NEVADA. RIDGING SUPPORTS HIGH CHANCES FOR ABOVE-NORMAL TEMPERATURES
OVER ALASKA. THE CONSOLIDATION FORECAST TOOL SUPPORTS ENHANCED PROBABILITIES
FOR ABOVE-NORMAL TEMPERATURES ACROSS HAWAII, BUT WITH REDUCED PROBABILITIES TO
THE NORTH DUE TO THE POTENTIAL FOR TROUGHING TO DEVELOP OVER THE REGION.
THE AMPLIFIED MID-LEVEL PATTERN LEADS TO A FAIRLY CONFIDENT PRECIPITATION
FORECAST, WITH THE ONLY UNCERTAINTY BEING THE STORM TRACK ALONG AND NEAR THE
EAST COAST. COMPARED TO YESTERDAY, THERE HAS BEEN A TREND TO A DRIER FORECAST
FOR MUCH OF THE EAST, WITH THE INCOMING TROUGHING PUSHING THE STORM TRACK WELL
TO THE SOUTH AND OFFSHORE. THEREFORE, THE HIGHEST CHANCES FOR ABOVE-NORMAL
PRECIPITATION ARE HIGHLIGHTED ACROSS THE GULF COAST AND SOUTHEAST. NEAR-NORMAL
PRECIPITATION IS FORECAST ACROSS THE NORTHEAST DUE TO DIFFERENCES IN THE
REFORECAST TOOLS WITH THE ECENS (GEFS) BEING DRIER (WETTER), AND SOME POTENTIAL
FOR A SURFACE LOW AT THE BEGINNING OF THE PERIOD AS THE TROUGH INITIALLY PUSHES
INTO THE REGION. ENHANCED CHANCES FOR BELOW-NORMAL PRECIPITATION ARE FAVORED
ACROSS THE TENNESSEE, OHIO, AND UPPER AND MIDDLE MISSISSIPPI VALLEY TIED TO
INCOMING SURFACE HIGH PRESSURE. ELEVATED LAKE EFFECT SNOW CHANCES SLIGHTLY
TILTS THE ODDS TOWARD ABOVE-NORMAL PRECIPITATION ACROSS THE GREAT LAKES.
ANOMALOUS RIDGING ACROSS THE WEST SUPPORTS HIGH CHANCES FOR BELOW-NORMAL
PRECIPITATION FROM THE ROCKIES TO THE PACIFIC COAST, WITH OCCASIONAL SHORTWAVES
MOVING OVERTOP THE RIDGE AXIS AND ON THE BACKSIDE OF THE DOWNSTREAM TROUGHING
LEADING TO ELEVATED CHANCES FOR ABOVE-NORMAL PRECIPITATION ACROSS THE HIGH
PLAINS. INCREASED SOUTHERLY FLOW ALONG WITH WEAK TROUGHING OVER THE BERING SEA
FAVORS ELEVATED CHANCES OF ABOVE-NORMAL PRECIPITATION OVER MOST OF ALASKA, WITH
THE HIGHEST CHANCES ACROSS THE NORTHWESTERN MAINLAND DUE TO THE PROJECTED
NORTHWARD SHIFT IN THE STORM TRACK AND REDUCED PRECIPITATION CLIMATOLOGY IN
THIS REGION. NEAR- TO ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS HAWAII.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON
DAY 8, 35% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY'S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND 20% OF TODAY'S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: WELL ABOVE AVERAGE, 5 OUT OF 5,
DUE TO VERY GOOD MODEL AGREEMENT REGARDING AN AMPLIFIED MID-LEVEL PATTERN OVER
THE FORECAST DOMAIN AND A MAJOR ARCTIC OUTBREAK ACROSS THE EASTERN HALF OF THE
U.S.
8-14 DAY OUTLOOK FOR JAN 21 - 27 2025
THE 500-HPA HEIGHT PATTERN DURING WEEK-2 REMAINS GENERALLY PERSISTENT WITH THAT
OF THE 6-10 DAY PERIOD, WITH SOME DECREASE IN AMPLITUDE IN THE LONGWAVE
FEATURES. THE GEFS AND CMCE BEGIN TO BUILD POSITIVE HEIGHT ANOMALIES ACROSS THE
EAST WHICH COULD BE CONSISTENT WITH THE START OF AN MJO-INDUCED PATTERN CHANGE.
HOWEVER, ALL OF THE MODELS APPEAR TO BEGIN RELOADING THE LONGWAVE TROUGHING
ACROSS THE PLAINS AND UPPER MIDWEST SO THE EXACT EVOLUTION LATER IN WEEK-2 AND
BEYOND REMAINS UNCERTAIN. THE MANUAL HEIGHT BLEND FOR WEEK-2 DEPICTS
BELOW-NORMAL HEIGHTS ACROSS MOST OF THE CONUS EAST OF THE ROCKIES, WITH THE
EXCEPTION BEING THE COASTAL SOUTHEAST AND THE FLORIDA PENINSULA WHERE WEAKLY
ABOVE-NORMAL HEIGHTS ARE INDICATED. ABOVE-NORMAL HEIGHTS CONTINUE TO BE
DEPICTED WEST OF THE ROCKIES AND EXTENDING NORTHWARD THROUGH ALASKA UNDERNEATH
RIDGING. NEAR-NORMAL HEIGHTS REMAIN FAVORED FOR HAWAII DUE TO A VARIABLE HEIGHT
PATTERN.
ENHANCED CHANCES FOR BELOW-NORMAL TEMPERATURES ARE FORECAST ACROSS MOST OF THE
CONUS DURING WEEK-2. BY THE START OF THE PERIOD, THE LARGEST NEGATIVE
TEMPERATURE ANOMALIES ARE PREDICTED TO SHIFT INTO THE EASTERN U.S., AS SOME
MODERATION BEGINS ACROSS THE CENTRAL CONUS, WITH THE MOST EXTREME COLD LIKELY
SUBSIDING. LATER IN WEEK-2, THIS MODERATION IS FORECAST TO SPREAD EASTWARD,
ALTHOUGH TEMPERATURES ARE STILL FORECAST TO BE BELOW-NORMAL. TODAY’S FORECAST
DEPICTS THE HIGHEST CHANCES (GREATER THAN 70 PERCENT) OF BELOW-NORMAL
TEMPERATURES ACROSS MUCH OF THE EASTERN THIRD OF THE CONUS. THE GEFS AND ECENS
REFORECAST TOOLS SUPPORT ENHANCED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES
ACROSS THE SOUTHWEST TIED TO RIDGING AND INCREASING DOWNSLOPE WINDS, WITH
HIGHER PROBABILITIES EXTENDING THROUGH ALASKA. THE CONSOLIDATION FORECAST TOOL
SUPPORTS ENHANCED ODDS FOR ABOVE-NORMAL TEMPERATURES ACROSS HAWAII.
SIMILAR TO THE 6-10 DAY PERIOD, THE HIGHEST ODDS FOR ABOVE-NORMAL PRECIPITATION
ARE FORECAST ALONG THE TROUGH AXIS, ACROSS THE NORTHERN HIGH PLAINS, AND THE
GULF COAST AND SOUTHEAST. THE STORM TRACK ACROSS THE EAST COAST REMAINS
UNCERTAIN WITH THE ECENS REFORECAST TOOL CONTINUING TO FAVOR MORE WIDESPREAD
ELEVATED CHANCES FOR BELOW-NORMAL PRECIPITATION COMPARED TO THE GEFS REFORECAST
TOOL WHICH SIGNALS A MEAN STORM TRACK CLOSER TO THE COAST. THEREFORE,
NEAR-NORMAL PRECIPITATION IS FAVORED OVER THE TENNESSEE VALLEY AND ALONG THE
EAST COAST, WITH BELOW-NORMAL PRECIPITATION PROBABILITIES INCREASED FURTHER
INLAND ACROSS THE MIDWEST AND INTERIOR NORTHEAST. BELOW-NORMAL PRECIPITATION
CHANCES CONTINUE TO BE ENHANCED ACROSS THE WEST TIED TO RIDGING. THE REFORECAST
TOOLS SUPPORT ENHANCED CHANCES FOR ABOVE-NORMAL PRECIPITATION ACROSS ALASKA,
WITH ABOVE-NORMAL PRECIPITATION ODDS ALSO REMAINING ELEVATED ACROSS HAWAII.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 40% OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 20% 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 HEIGHT PATTERN, OFFSET BY
DECREASING AMPLIFICATION AND SOME UNCERTAINTY IN THE EVOLUTION TOWARD THE END
OF 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
JANUARY 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:
19661227 - 19691230 - 19751231 - 19550110 - 19550121
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:
19661228 - 19691229 - 19751231 - 19550109 - 19550121
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 19 - 23 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B B OREGON B B NRN CALIF N B
SRN CALIF B B IDAHO B B NEVADA B B
W MONTANA B B E MONTANA B A WYOMING B A
UTAH B B ARIZONA B B COLORADO B N
NEW MEXICO B B N DAKOTA B A S DAKOTA B N
NEBRASKA B N KANSAS B N OKLAHOMA B N
N TEXAS B N S TEXAS B A W TEXAS B N
MINNESOTA B N IOWA B B MISSOURI B B
ARKANSAS B B LOUISIANA B A WISCONSIN B N
ILLINOIS B B MISSISSIPPI B N MICHIGAN B A
INDIANA B B OHIO B N KENTUCKY B B
TENNESSEE B B ALABAMA B N NEW YORK B N
VERMONT B N NEW HAMP B N MAINE B N
MASS B N CONN B N 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 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 A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 21 - 27 2025
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B B OREGON B B NRN CALIF A B
SRN CALIF A B IDAHO B B NEVADA A B
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B B ARIZONA B B COLORADO B N
NEW MEXICO B B N DAKOTA B A S DAKOTA B N
NEBRASKA B N KANSAS B N OKLAHOMA B N
N TEXAS B A S TEXAS B A W TEXAS B N
MINNESOTA B N IOWA B N MISSOURI B N
ARKANSAS B N LOUISIANA B A WISCONSIN B N
ILLINOIS B N MISSISSIPPI B A MICHIGAN B N
INDIANA B N OHIO B B KENTUCKY B N
TENNESSEE B N ALABAMA B A NEW YORK B B
VERMONT B B NEW HAMP B B MAINE B B
MASS B N CONN B N RHODE IS B N
PENN B B NEW JERSEY B N W VIRGINIA B N
MARYLAND B N DELAWARE B N VIRGINIA B N
N CAROLINA B N S CAROLINA B N 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 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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