909
FXUS06 KWBC 152002
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 15 2024
6-10 DAY OUTLOOK FOR JAN 21 - 25 2024
MODELS ARE IN VERY GOOD AGREEMENT TODAY SHOWING A FAIRLY AMPLIFIED MID-LEVEL
PATTERN. A MEAN 500-HPA TROUGH AXIS EXTENDS SOUTHWARD THROUGH MAINLAND ALASKA,
WITH A CLOSED LOW OF ABOUT 510-DM CENTERED NEAR THE ALEUTIANS AND A DOWNSTREAM
MID-LEVEL RIDGE ACROSS WESTERN CANADA. FARTHER EAST, THERE IS A DEEP MEAN
TROUGH CENTERED OVER BAFFIN BAY WITH 500-HPA HEIGHTS BELOW 492-DM, AND AN AXIS
EXTENDING SOUTHEASTWARD ACROSS SOUTHERN GREENLAND AND INTO THE NORTH ATLANTIC.
TO THE SOUTH ACROSS THE MID-LATITUDES, A STRONG MEAN RIDGE COVERS MOST OF
CENTRAL AND SOUTHERN CANADA AND THE CONTIGUOUS U.S. (CONUS), WITH THE LARGEST
POSITIVE MEAN 500-HPA ANOMALIES CENTERED NEAR THE EASTERN GREAT LAKES. THE GEFS
AND THE EUROPEAN ENSEMBLE MEAN DEPICT 500-HPA HEIGHT ANOMALIES EXCEEDING +24-DM
IN THIS REGION FOR THE 6 TO 10 DAY PERIOD AS A WHOLE. SUBNORMAL 500-HPA HEIGHTS
ARE RESTRICTED TO THE SOUTHERN ROCKIES AND HIGH PLAINS ASSOCIATED WITH A
LOWER-LATITUDE TROUGH WITH AN AXIS EXTENDING SOUTHWARD TOWARD CENTRAL MEXICO.
WITH MOST OF THE CONUS UNDER OR JUST UPSTREAM FROM A FLAT 500-HPA RIDGE,
ABOVE-NORMAL TEMPERATURES ARE FAVORED THROUGHOUT THE CONUS EXCEPT OVER THE
SOUTHEAST, AS SHOWN BY BIAS-CORRECTED GUIDANCE AND REFORECAST TOOLS. ODDS FOR
SIGNIFICANTLY ABOVE-NORMAL TEMPERATURES EXCEED 80 PERCENT OVER MUCH OF THE
GREAT LAKES AND NORTHERN MINNESOTA, NEAR THE GREATEST 500-HPA HEIGHT
DEPARTURES. WITH FAIRLY DEEP MILD AND MOIST FLOW COMING INTO THE CONUS FROM
BOTH THE GULF OF MEXICO AND THE NORTH PACIFIC, MOST OF THE CONUS HAS ENHANCED
CHANCES FOR ABOVE-NORMAL PRECIPITATION. SUBNORMAL TOTALS ARE FAVORED ONLY IN
THE NORTHERN PLAINS, THE EASTERN MIDDLE ATLANTIC REGION, AND PARTS OF THE
NORTHEAST, WHICH ARE FARTHEST AWAY FROM THE STRONG LOW-LEVEL MOISTURE INFLUX.
THE GREATEST ODDS FOR SURPLUS PRECIPITATION (EXCEEDING 70 PERCENT) ARE CENTERED
IN THE SOUTHERN PLAINS AND MUCH OF CALIFORNIA.
ALASKA WILL BE DOMINATED BY SOUTHEAST-TO-NORTHWEST LOWER AND MID-LEVEL FLOW
ACROSS THE STATE, WITH AN ARCTIC SURFACE HIGH TO THE NORTH AND A MEAN SURFACE
LOW PRESSURE NEAR THE MID-LEVEL TROUGH IN THE NORTH PACIFIC. THE ARCTIC HIGH
PRESSURE FAVORS BELOW NORMAL TEMPERATURES ACROSS MOST OF THE STATE EXCEPT IN
SOUTHEASTERN SECTIONS, WHERE STRONG LOW-LEVEL FLOW WILL BE FROM THE SOUTHEAST,
BRINGING IN MOISTURE AND MILD AIR. THIS SET-UP ALSO FAVORS ABOVE-NORMAL
PRECIPITATION OVER SOUTHEASTERN AND SOUTH-CENTRAL ALASKA NORTHWARD TOWARD
EAST-CENTRAL ALASKA WHILE THE EAST-TO-WEST FETCH WILL BE COMING ACROSS A LONG
STRETCH OF LAND IN WESTERN ALASKA, FAVORING BELOW-NORMAL PRECIPITATION THERE.
MOST OF THE TOOLS FAVOR WETTER- AND WARMER-THAN-NORMAL WEATHER ACROSS HAWAII,
CONSISTENT WITH RELATIVELY LOW 500-HPA HEIGHTS TO THE NORTH AND NORTHWEST OF
THE STATE.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 25% OF TODAY'S GFS
SUPERENSEMBLE MEAN CENTERED ON DAY 8, 25% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, 25% OF TODAY'S OPERATIONAL 0Z ECMWF 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: MUCH ABOVE AVERAGE, 5 OUT OF 5,
GIVEN UNUSUALLY GOOD AGREEMENT IN BOTH THE RAW MODEL OUTPUTS AND THE DERIVED
BIAS-CORRECTED AND REFORECAST TOOLS.
8-14 DAY OUTLOOK FOR JAN 23 - 29 2024
FOR WEEK-2, THE DETAILS OF THE MODEL SOLUTIONS DO NOT AGREE QUITE AS WELL AS
DURING THE 6 TO 10 DAY PERIOD, BUT ALL SHOW A SIMILAR MID-LEVEL PATTERN WITH AN
ANOMALOUS MEAN TROUGH OVER BAFFIN BAY, GREENLAND, AND SURROUNDING AREAS
ABOVE-NORMAL 500-HPA HEIGHTS ARE FORECAST ACROSS MOST OF THE CONUS AND CANADA,
CENTERED OVER OR NEAR THE GREAT LAKES WITH A SECONDARY RIDGE AXIS ALONG WESTERN
NORTH AMERICA. A RELATIVELY WEAK MID-LEVEL TROUGH PERSISTS OVER SOUTHERN
SECTIONS OF THE ROCKIES AND HIGH PLAINS. THE CANADIAN ENSEMBLE MEAN IS WEAKER
THAN THE OTHER TWO ENSEMBLE MEANS, AND HAS A MORE POSITIVE TILT TO THE
LOWER-LATITUDE TROUGH. FARTHER WEST, MODEL AGREEMENT IS NOT AS GOOD OVER ALASKA
AND THE NORTH PACIFIC. ALL GUIDANCE SHOWS ABOVE-NORMAL 500-HPA HEIGHTS ACROSS
MOST OF THE STATE, BUT ANOMALIES ARE SLIGHTLY STRONGER AND MORE WIDESPREADS IN
THE GEFS THAN IN THE EUROPEAN AND CANADIAN ENSEMBLE MEANS. ALSO, THE GEFS
CENTERS A REGION OF BELOW-NORMAL 500-HPA HEIGHTS JUST NORTH OF HAWAII WHILE THE
OTHER TWO ENSEMBLE MEANS SHOW A LARGER FEATURE THAT EXTENDS NORTHWARD TOWARD
THE ALEUTIANS. THE PATTERN SHOWN IN THE EUROPEAN AND CANADIAN ENSEMBLE MEANS IS
SLIGHTLY FAVORED SINCE THE PREPONDERANCE OF TOOLS LEANS IN THIS DIRECTION, BUT
IN ANY CASE, THE RESULTING SENSIBLE WEATHER ACROSS THE STATE IS SIMILAR FOR
BOTH SOLUTIONS.
THE PREVAILING ABOVE-NORMAL 500-HPA HEIGHTS WILL FAVOR ABOVE-NORMAL
TEMPERATURES THROUGHOUT THE CONUS, WITH THE GREATEST CHANCES OF OCCURRENCE
ACROSS THE GREAT LAKES (OVER 80 PERCENT) CLOSEST TO THE 500-HPA POSITIVE HEIGHT
ANOMALY. CHANCES FOR WARMER THAN NORMAL WEATHER EXCEED 60 PERCENT EVERYWHERE
FROM THE MISSISSIPPI VALLEY TO THE ATLANTIC COAST, AND SIMILAR CHANCES FOR
WARMTH EXIST ALONG THE WEST-CENTRAL CONUS COAST NEAR THE WESTERN NORTH AMERICA
MEAN MID-LEVEL RIDGE. ABOVE-NORMAL PRECIPITATION IS ALSO FAVORED FOR MOST OF
THE CONUS, PARTICULARLY ACROSS THE SOUTHERN GREAT PLAINS AND LOWER MISSISSIPPI
VALLEY, WHERE ODDS EXCEED 60 PERCENT. THIS REGION SHOULD EXPERIENCE ENHANCED
MOIST FLOW FROM THE SOUTH OR SOUTHEAST, AND IS UPSTREAM FROM THE LOWER-LATITUDE
TROUGH EXTENDING FROM THE SOUTHERN ROCKIES INTO CENTRAL MEXICO. ONLY PARTS OF
THE NORTHERN PLAINS HAVE SLIGHTLY ELEVATED ODDS FOR SUBNORMAL PRECIPITATION.
WITH A MODERATELY STRONG FETCH OF AIR CROSSING ALASKA BETWEEN ARCTIC HIGH
PRESSURE TO THE NORTH AND LOWER SURFACE PRESSURES IN THE NORTH PACIFIC, WEEK-2
SHOULD FEATURE CONDITIONS SIMILAR TO THE 6- TO 10-DAY PERIOD, WITH WARMER AND
WETTER CONDITIONS FAVORED IN SOUTHEASTERN PARTS OF THE STATE WHILE COLDER AND
DRIER WEATHER IS FAVORED OVER MOST OF THE WESTERN MAINLAND. CONDITIONS SHOULD
BE CLOSER TO NORMAL ALONG MOST OF THE ARCTIC COAST.
SUBNORMAL MID-LEVEL HEIGHTS ARE EXPECTED TO CONTINUE TO THE NORTHWEST OF
HAWAII, WITH UNUSUALLY HIGH 500-HPA HEIGHTS TO THE SOUTH AND SOUTHEAST OF THE
ISLAND CHAIN. AS A RESULT, WARMER- AND WETTER-THAN-NORMAL CONDITIONS ARE
EXPECTED TO CONTINUE.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 40% OF TODAY'S GFS
SUPERENSEMBLE MEAN CENTERED ON DAY 11, 15% OF TODAY'S OPERATIONAL 6Z GFS
CENTERED ON DAY 11, 25% 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 NORMAL, 4 OUT OF 5, FOR GOOD
OVERALL MODEL AGREEMENT, TEMPERED BY INCREASED UNCERTAINTY IN THE DETAILS OF
THE STRENGTH AND TIMING OF MID-LEVEL FEATURES.
FORECASTER: RICH TINKER
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:
19781226 - 19590102 - 19681228 - 19700102 - 19960129
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:
19781226 - 19710103 - 19700102 - 19590102 - 19681229
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 21 - 25 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF A A
SRN CALIF A A IDAHO A A NEVADA A A
W MONTANA A A E MONTANA A B WYOMING A N
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA A B S DAKOTA A B
NEBRASKA A A KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A A W TEXAS A A
MINNESOTA A N 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 N
VERMONT A N NEW HAMP A B MAINE A B
MASS A B CONN A B RHODE IS A B
PENN A N NEW JERSEY A B W VIRGINIA A A
MARYLAND A N DELAWARE A B VIRGINIA A N
N CAROLINA N N S CAROLINA N A GEORGIA N A
FL PNHDL N A FL PENIN N A AK N SLOPE B B
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 A A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 23 - 29 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF A A
SRN CALIF A A IDAHO A A NEVADA A A
W MONTANA A N E MONTANA A N WYOMING A N
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA A N S DAKOTA A N
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 A CONN A A RHODE IS A A
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 N N
AK ALEUTIAN B N AK WESTERN B N AK INT BSN N N
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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