661
FXUS06 KWBC 092003
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 09 2024
6-10 DAY OUTLOOK FOR FEB 15 - 19 2024
A MAJOR PATTERN CHANGE IS LIKELY DURING MID-FEBRUARY AS A NEGATIVE ARCTIC
OSCILLATION (-AO) BECOMES WELL-ESTABLISHED. DESPITE THIS -AO WHICH TYPICALLY
FAVORS ANOMALOUS COLD ACROSS THE CENTRAL AND EASTERN CONTIGUOUS U.S., THE
INCREASING PACIFIC FLOW RESULTS IN LOWER FORECAST CONFIDENCE FOR A WIDESPREAD
COLDER OUTCOME. THE MANUAL 500-HPA HEIGHT BLEND (NEAR EQUAL WEIGHTING OF THE
GEFS, ECMWF, AND CANADIAN ENSEMBLE MEANS) DEPICTS HIGH AMPLITUDE TROUGHS OVER
THE NORTHEASTERN PACIFIC AND NORTHWESTERN ATLANTIC AND A HIGH AMPLITUDE RIDGE
CENTERED ACROSS THE HIGHER LATITUDES OF WESTERN NORTH AMERICA. COMPARED TO
EARLY FEBRUARY, TEMPERATURES ARE FORECAST TO MODERATE AND BE CLOSER TO
CLIMATOLOGY ACROSS THE CENTRAL AND EASTERN CONUS. STRONG COLD AIR ADVECTION,
ASSOCIATED WITH AN INTENSE LOW PRESSURE SYSTEM OVER THE CANADIAN MARITIMES
FAVORS BELOW-NORMAL TEMPERATURES ALONG THE EAST COAST. A SOUTHERN STREAM
SHORTWAVE TROUGH AND NEGATIVE 500-HPA HEIGHT ANOMALIES SUPPORT INCREASED
BELOW-NORMAL TEMPERATURE PROBABILITIES FOR MUCH OF TEXAS AND GULF COAST.
BELOW-NORMAL TEMPERATURES ARE ALSO MORE LIKELY ACROSS THE NORTHERN GREAT PLAINS
DUE TO ARCTIC HIGH PRESSURE SHIFTING SOUTHWARD. THIS ARCTIC HIGH MAY PROVIDE A
BRIEF PERIOD OF ANOMALOUS COLD TO THE MIDWEST, BUT UNCERTAINTY IS HIGH ON ITS
DURATION AND SPATIAL EXTENT. ELSEWHERE, ACROSS THE CENTRAL GREAT PLAINS AND
MISSISSIPPI VALLEY, 6-10 DAY TEMPERATURE TOOLS HAVE TRENDED WARMER AS
INCREASING PACIFIC FLOW SEEMS TO BE THE MORE DOMINANT INFLUENCE. ENHANCED
PACIFIC FLOW SUPPORTS INCREASED ABOVE-NORMAL TEMPERATURE PROBABILITIES ACROSS A
MAJORITY OF THE WEST.
FOLLOWING A BREAK IN THE HEAVY PRECIPITATION ACROSS CALIFORNIA AND THE
SOUTHWEST, A RETURN OF A WET PATTERN IS LIKELY FOR THESE AREAS LATER NEXT WEEK
AS THE ANOMALOUS TROUGH SHIFTS CLOSER TO THE WEST COAST. ABOVE-NORMAL
PRECIPITATION PROBABILITIES CONTINUE TO INCREASE ACROSS CALIFORNIA AND THE
SOUTHWEST AS THE WET PATTERN RESUMES. PROBABILITIES FOR ABOVE-NORMAL
PRECIPITATION TAPER OFF TO THE NORTH ACROSS THE WESTERN CONUS SINCE MODEL
GUIDANCE REMAINS CONSISTENT THAT THE PRIMARY STORM TRACK REMAINS SOUTH OF THE
40TH PARALLEL. AS THE LONGWAVE 500-HPA TROUGH AXIS SHIFTS EASTWARD TOWARDS THE
WEST COAST, THERE IS AN INCREASING CHANCE OF SURFACE LOW DEVELOPMENT ACROSS THE
HIGH PLAINS. THEREFORE, A SLIGHT LEAN TOWARDS ABOVE-NORMAL PRECIPITATION IS
FORECAST THROUGHOUT THE GREAT PLAINS. ON DAY 6 AND 7 (FEBRUARY 15 AND 16), A
SOUTHERN STREAM SHORTWAVE TROUGH IS FORECAST TO RESULT IN SURFACE CYCLOGENESIS
EITHER ALONG THE GULF COAST OR NORTHERN GULF OF MEXICO. ALONG THE PREDICTED
TRACK OF THIS SHORTWAVE TROUGH AND ASSOCIATED LOW PRESSURE SYSTEM, ABOVE-NORMAL
PRECIPITATION IS FAVORED ACROSS THE SOUTHERN GREAT PLAINS, GULF COAST STATES,
AND SOUTHEAST. THERE IS LIKELY TO BE A SHARP SOUTH-TO-NORTH GRADIENT IN
PRECIPITATION AMOUNTS FROM THE GULF COAST TO THE TENNESSEE VALLEY AND
CAROLINAS. SINCE THIS LOW PRESSURE SYSTEM IS EXPECTED TO REMAIN SUPPRESSED,
BELOW-NORMAL PRECIPITATION IS MORE LIKELY ACROSS THE OHIO VALLEY, NORTHERN
MID-ATLANTIC, AND NORTHEAST.
SOUTHERLY SURFACE FLOW FAVORS ABOVE-NORMAL TEMPERATURES ACROSS MUCH OF ALASKA,
EXCEPT FOR PARTS OF SOUTHEASTERN ALASKA DUE TO THE PROXIMITY OF ARCTIC HIGH
PRESSURE. SINCE THE STORM TRACK ACROSS THE NORTH PACIFIC IS EXPECTED TO BE
DISPLACED SOUTHWARD, MODEL SOLUTIONS CONTINUE TO FEATURE INCREASED BELOW-NORMAL
PRECIPITATION PROBABILITIES THROUGHOUT ALASKA.
A HIGHLY AMPLIFIED TROUGH OVER THE NORTH PACIFIC LEADS TO NORTHERLY SURFACE
FLOW, PROMOTING INCREASED BELOW-NORMAL TEMPERATURE PROBABILITIES ACROSS HAWAII.
THE CONSOLIDATION TOOL SUPPORTS NEAR TO BELOW NORMAL PRECIPITATION.
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: AVERAGE, 3 OUT OF 5, DUE TO GOOD
AGREEMENT AMONG THE PRECIPITATION TOOLS OFFSET BY UNCERTAINTY ON THE MAGNITUDE
OF ANOMALOUS COLD OVERSPREADING THE CENTRAL AND EASTERN CONUS.
8-14 DAY OUTLOOK FOR FEB 17 - 23 2024
THE GEFS, ECMWF, AND CANADIAN ENSEMBLE MEANS DEPICT A HIGHLY AMPLIFIED TROUGH
NEAR THE WEST COAST AND MAINTAIN THE POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE
HIGHEST LATITUDES OF NORTH AMERICA. MOST GEFS MEMBERS FEATURE A CONTINUATION OF
A -AO THROUGH LATE FEBRUARY BUT ENSEMBLE SPREAD INCREASES LATER IN WEEK-2 WITH
A FEW MEMBERS GOING POSITIVE. ONE NOTABLE CHANGE TODAY IS THAT MODEL SOLUTIONS
HAVE A MID-LEVEL RIDGE SHIFTING EAST TOWARDS THE NORTH-CENTRAL CONUS WITH
POSITIVE 500-HPA HEIGHT ANOMALIES DEVELOPING OVER SOUTHERN CANADA. THIS CHANGE
IN THE LONGWAVE PATTERN WOULD DECREASE THE CHANCE FOR ANY SUSTAINED COLD AIR
ADVECTION ACROSS THE GREAT PLAINS AND MIDWEST AND THE DYNAMICAL MODEL OUTPUT
HAS TRENDED WARMER ACROSS THE CENTRAL AND EASTERN CONUS. THEREFORE, NEAR TO
ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MORE OF THESE AREAS COMPARED TO
PREVIOUS DAYS. THE MOST LIKELY AREA FOR BELOW-NORMAL TEMPERATURES IS ALONG THE
EAST COAST WHERE COLD AIR ADVECTION IS FORECAST TO BE THE STRONGEST AND THE
NORTHERN GREAT PLAINS DUE TO ARCTIC HIGH PRESSURE. PREVAILING ENHANCED PACIFIC
FLOW CONTINUES TO FAVOR ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE WEST.
HOWEVER, BELOW-NORMAL TEMPERATURES ARE MORE LIKELY FOR PARTS OF SOUTHERN
CALIFORNIA AND THE SOUTHWEST DUE MOSTLY TO THE WET PATTERN.
FORECAST CONFIDENCE REMAINS HIGH THAT A WET PATTERN RETURNS TO CALIFORNIA AND
THE SOUTHWEST AS AN AMPLIFIED 500-HPA TROUGH SHIFTS CLOSER TO THE WEST COAST.
THE ENSEMBLE MEANS DEPICT THE RENEWAL OF THIS WET PATTERN BY THE BEGINNING OF
WEEK-2, FEBRUARY 17. TOTAL PRECIPITATION AMOUNTS FROM THE ENSEMBLE MEANS ARE
ABOVE 2 INCHES (LIQUID EQUIVALENT) ACROSS MUCH OF CALIFORNIA, SUPPORTING
ABOVE-NORMAL PRECIPITATION PROBABILITIES THAT EXCEED 60 PERCENT AND EVEN 70
PERCENT FOR SOUTHERN CALIFORNIA. THESE RELATIVELY HIGH PROBABILITIES ALSO
INCLUDE THE DRIER CLIMATOLOGY AREAS OF THE DESERT SOUTHWEST. ENHANCED PACIFIC
FLOW SUPPORTS ELEVATED ABOVE-NORMAL PRECIPITATION PROBABILITIES ACROSS MUCH OF
THE GREAT BASIN AND ROCKIES. DUE TO AN INCREASING CHANCE OF SURFACE LOW
DEVELOPMENT TO THE LEE OF THE ROCKIES, ABOVE-NORMAL PRECIPITATION IS FAVORED
ACROSS THE CENTRAL TO SOUTHERN GREAT PLAINS. HEAVY PRECIPITATION IS EXPECTED TO
BE ONGOING ACROSS PARTS OF THE SOUTHEAST ON DAY 8 (FEBRUARY 17) AND ANOTHER LOW
PRESSURE SYSTEM MAY AFFECT THIS REGION BY THE END OF WEEK-2. SIMILAR TO THE
6-10 DAY PERIOD, THERE IS LIKELY TO BE A SHARP SOUTH-TO-NORTH GRADIENT IN
PRECIPITATION AMOUNTS FROM THE GULF COAST AND SOUTHEAST TO THE OHIO VALLEY AND
NORTHEAST.
TEMPERATURE PROBABILITIES ARE LIMITED THROUGHOUT ALASKA AS IT REMAINS UNCLEAR
IF SOUTHERLY OR EASTERLY SURFACE FLOW BECOMES MORE DOMINANT. ABOVE-NORMAL
TEMPERATURES ARE MORE LIKELY ACROSS THE WESTERN TWO-THIRDS OF THE STATE WITH A
SLIGHT LEAN TOWARDS BELOW-NORMAL TEMPERATURES FOR PARTS OF SOUTHEASTERN ALASKA.
ONSHORE FLOW SLIGHTLY FAVORS ABOVE-NORMAL PRECIPITATION ACROSS SOUTHERN ALASKA
WITH NEAR NORMAL OR A SLIGHT LEAN TOWARDS BELOW-NORMAL PRECIPITATION FORECAST
FOR THE REMAINDER OF THE STATE.
THE DEEP 500-HPA TROUGH OVER THE NORTHEASTERN PACIFIC ALONG WITH A PERIOD OF
NORTHERLY SURFACE FLOW FAVORS BELOW-NORMAL TEMPERATURES THROUGHOUT HAWAII.
BASED ON THE CONSOLIDATION TOOL, NEAR NORMAL PRECIPITATION IS FORECAST.
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: AVERAGE, 3 OUT OF 5, DUE TO
CONTINUED GOOD AGREEMENT AMONG THE PRECIPITATION TOOLS OFFSET BY POOR AGREEMENT
AND INCONSISTENCY AMONG THE TEMPERATURE TOOLS.
FORECASTER: BRAD PUGH
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 15.
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:
19510219 - 19810223 - 20040202 - 19550218 - 20050207
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:
19510219 - 19810222 - 20050208 - 19690221 - 20040203
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 15 - 19 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON A A NRN CALIF A A
SRN CALIF N A IDAHO A A NEVADA A A
W MONTANA B A E MONTANA B A WYOMING N A
UTAH A A ARIZONA N A COLORADO N A
NEW MEXICO N A N DAKOTA B A S DAKOTA N A
NEBRASKA N A KANSAS N A OKLAHOMA N A
N TEXAS B A S TEXAS B A W TEXAS N A
MINNESOTA N N IOWA A N MISSOURI A N
ARKANSAS N N LOUISIANA B A WISCONSIN A N
ILLINOIS A N MISSISSIPPI B A MICHIGAN A N
INDIANA N B OHIO N B KENTUCKY N B
TENNESSEE N B ALABAMA B A NEW YORK B B
VERMONT B B NEW HAMP B B MAINE B B
MASS B B CONN B B RHODE IS B B
PENN B B NEW JERSEY B B W VIRGINIA B B
MARYLAND B B DELAWARE B B VIRGINIA B N
N CAROLINA B N S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN B A AK N SLOPE A B
AK ALEUTIAN A B AK WESTERN A B AK INT BSN A B
AK S INT A B AK SO COAST A B AK PNHDL B B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 17 - 23 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A A NRN CALIF A A
SRN CALIF B A IDAHO A A NEVADA A A
W MONTANA B N E MONTANA B N WYOMING N A
UTAH A A ARIZONA B A COLORADO N A
NEW MEXICO N A N DAKOTA N N S DAKOTA N A
NEBRASKA N A KANSAS N A OKLAHOMA N A
N TEXAS N A S TEXAS B A W TEXAS N A
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS N N LOUISIANA B A WISCONSIN A B
ILLINOIS A N MISSISSIPPI N A MICHIGAN A B
INDIANA N N OHIO N N KENTUCKY N N
TENNESSEE N N ALABAMA N A NEW YORK B B
VERMONT B B NEW HAMP B B MAINE B B
MASS B B CONN B B RHODE IS B B
PENN N B NEW JERSEY B B W VIRGINIA N 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 B
AK ALEUTIAN A N AK WESTERN A B AK INT BSN N B
AK S INT A A AK SO COAST A A AK PNHDL B N
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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