510
FXUS06 KWBC 161929
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU MAY 16 2024
6-10 DAY OUTLOOK FOR MAY 22 - 26 2024
TODAY’S MODEL SOLUTIONS ARE VERY SIMILAR TO YESTERDAY’S AND THE GEFS, ECMWF
ENSEMBLE MEAN (ECENS), AND CANADIAN ENSEMBLE MEAN (CMCE) ALL DEPICT A SIMILAR
SYNOPTIC PICTURE OVER THE FORECAST DOMAIN DURING THE 6-10 DAY FORECAST PERIOD.
AS IS TYPICALLY THE CASE, THERE ARE RELATIVELY MINOR DIFFERENCES AMONG TODAY’S
MODELS IN THE PREDICTED AMPLITUDE AND PHASE OF SOME LONGWAVE FEATURES. TODAY’S
MANUAL BLEND FEATURES NEGATIVE 500-HPA HEIGHT ANOMALIES OVER MUCH OF THE
WESTERN AND NORTH-CENTRAL CONTIGUOUS U.S. (CONUS) WITH THE LARGEST NEGATIVE
DEPARTURES AROUND -75 METERS OVER THE NORTHERN ROCKIES. POSITIVE HEIGHT
ANOMALIES ARE FORECAST OVER THE SOUTHERN TIER OF THE CONUS, WITH 30-60 METER
DEPARTURES CENTERED OVER THE WESTERN GULF REGION. THESE POSITIVE HEIGHT
ANOMALIES ARE ASSOCIATED WITH A SUBTROPICAL RIDGE. HEIGHTS OVER THE NORTHEAST
AND MID-ATLANTIC REGION ARE FORECAST TO BE NEAR-AVERAGE. OVER THE ALASKA
DOMAIN, A WEAK TROUGH IS DEPICTED OVER THE BERING SEA AND SOUTHWESTERN
MAINLAND, WITH MID-LEVEL RIDGING ELSEWHERE. THIS MID-LEVEL RIDGING REPRESENTS
THE NORTHEASTERN EXTENT OF A BROAD, ZONALLY ELONGATED ANOMALOUS RIDGE THAT IS
PREDICTED OVER MUCH OF THE NORTH PACIFIC. MAXIMUM POSITIVE HEIGHT ANOMALIES
ASSOCIATED WITH THIS RIDGE EXCEED +150 METERS SOUTH OF THE ALEUTIANS. A WEAK
MID-LEVEL TROUGH IS ANTICIPATED NORTHWEST OF THE HAWAIIAN ISLANDS.
BELOW NORMAL TEMPERATURE CHANCES ARE INCREASED OVER SOUTHWESTERN MAINLAND
ALASKA AND THE ADJACENT ALASKA PENINSULA, CONSISTENT WITH MOST TEMPERATURE
GUIDANCE AND THE FORECAST OF A WEAK TROUGH IN THAT REGION. MID-LEVEL RIDGING
AND POSITIVE HEIGHT ANOMALIES FAVOR ABOVE NORMAL TEMPERATURE CHANCES OVER THE
REMAINDER OF THE MAINLAND. FOR THE PANHANDLE, MOST OF THE RAW AND
BIAS-CORRECTED TEMPERATURES SUPPORT BELOW NORMAL TEMPERATURES, WHEREAS THE
VARIOUS REFORECAST TEMPERATURE FIELDS FAVOR ABOVE NORMAL TEMPERATURES. THE
MANUAL BLEND INDICATES A MEAN RIDGE AXIS AND NORTHERLY ANOMALOUS FLOW, WITH
WARM ADVECTION APPROACHING FROM THE SOUTHWEST. THE TEMPERATURE OUTLOOK IS VERY
DEPENDENT UPON AN EXPECTED COOL-TO-WARM TRANSITION, AND NEAR NORMAL APPEARS TO
BE THE MOST LIKELY CATEGORY. FROM THE NORTHWESTERN AND NORTH-CENTRAL CONUS
EASTWARD INTO THE GREAT LAKES REGION, BELOW NORMAL TEMPERATURES ARE FAVORED,
SUPPORTED BY MOST TOOLS AND MID-LEVEL TROUGHING. DISPARATE TEMPERATURE GUIDANCE
OVER THE SOUTHWEST SHOWS ANY OF THE THREE CATEGORIES ARE POSSIBLE, THOUGH NEAR
TO BELOW NORMAL TEMPERATURES ARE THE MOST PREVALENT. SUBTROPICAL RIDGING FAVORS
ABOVE NORMAL TEMPERATURES FOR MUCH OF THE SOUTHERN CONUS, WITH A NORTHWARD
EXTENSION OF THIS ANOMALOUS WARMTH EXPECTED ACROSS THE EASTERN THIRD OF THE
CONUS IN ADVANCE OF MID-LEVEL TROUGHING. PROBABILITIES FAVORING ABOVE NORMAL
TEMPERATURES EXCEED 80% FOR PORTIONS OF SOUTH TEXAS. IN HAWAII, A COMPROMISE
BETWEEN THE AUTO AND ERF CONSOLIDATION TOOLS FAVORS A SLIGHT TILT TOWARDS ABOVE
NORMAL TEMPERATURES FOR KAUAI AND OAHU, AND NEAR NORMAL TEMPERATURES FOR MAUI
AND THE BIG ISLAND.
AT THE START OF THE 6-10 DAY PERIOD, A STORM SYSTEM IS FORECASTED TO LIFT
NORTHWARD ACROSS THE GREAT LAKES REGION INTO SOUTHERN CANADA, WITH A COLD FRONT
EXTENDING SOUTHWESTWARD FROM THE SURFACE LOW. THIS COLD FRONT IS EXPECTED TO
STALL AS IT APPROACHES THE GULF COAST, AND SERVE TO FOCUS ABOVE NORMAL
PRECIPITATION ACROSS THE SOUTHEAST. BY THE MIDDLE OF THE PERIOD, LEE
CYCLOGENESIS IS ANTICIPATED OVER EASTERN COLORADO, WITH THE SURFACE LOW
TRACKING NORTHEASTWARD TOWARDS THE GREAT LAKES. THIS LOW PRESSURE SYSTEM IS
EXPECTED TO BRING WIDESPREAD ABOVE NORMAL PRECIPITATION TO MUCH OF THE CENTRAL
AND EASTERN CONUS. ABOVE NORMAL PRECIPITATION IS ALSO ANTICIPATED ACROSS THE
NORTHWESTERN QUARTER OF THE CONUS, IN ADVANCE OF A PREDICTED MID-LEVEL TROUGH
AND NEGATIVE HEIGHT ANOMALIES. ALL THESE AREAS OF FAVORED ABOVE NORMAL
PRECIPITATION ARE WELL SUPPORTED BY MOST OF THE FORECAST TOOLS. THE SUBTROPICAL
RIDGE FAVORS BELOW NORMAL PRECIPITATION FOR NEW MEXICO, SOUTHERN COLORADO,
WESTERN AND FAR SOUTHERN PARTS OF TEXAS, AND CENTRAL AND SOUTHERN FLORIDA.
ABOVE NORMAL PRECIPITATION CHANCES ARE ELEVATED OVER MOST OF ALASKA IN ADVANCE
OF A MID-LEVEL TROUGH AND WIDESPREAD ONSHORE FLOW. THE EXCEPTION IS OVER THE
PANHANDLE, WHERE NEAR TO BELOW NORMAL PRECIPITATION IS FAVORED UNDER A
MID-LEVEL RIDGE AND POSITIVE HEIGHT ANOMALIES. A COMPROMISE BETWEEN THE
HAWAIIAN AUTO AND CONSOLIDATION TOOLS FAVORS ANOMALOUSLY WET CONDITIONS
STATEWIDE IN ADVANCE OF A 500-HPA TROUGH.
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, WITH
GOOD RUN-TO-RUN CONTINUITY AMONG FORECAST MODELS, OFFSET BY DIFFERENCES BETWEEN
MODELS REGARDING STRENGTH AND POSITION OF VARIOUS SYNOPTIC FEATURES.
8-14 DAY OUTLOOK FOR MAY 24 - 30 2024
DURING WEEK-2, POSITIVE 500-HPA HEIGHT ANOMALIES PERSIST OVER THE NORTH PACIFIC
AND OVER MUCH OF THE SOUTHERN TIER OF THE CONUS. NEAR TO SLIGHTLY BELOW NORMAL
500-HPA HEIGHTS ARE PREDICTED OVER MUCH OF THE WESTERN CONUS, AND EXTENDING
EASTWARD ACROSS THE NORTHERN TIER TO THE GREAT LAKES REGION. THE FULL HEIGHT
FIELD DEPICTED BY THE MANUAL BLEND OVER THE CONUS FEATURES A LOW AMPLITUDE
TROUGH-RIDGE-TROUGH PATTERN. FOR ALASKA, A VERY WEAK TROUGH IS INDICATED IN THE
FULL HEIGHT FIELD ALONG THE WESTERN COAST, WITH MID-LEVEL RIDGING AND POSITIVE
HEIGHT ANOMALIES DOMINATING THE REMAINDER OF THE STATE. A WEAK TROUGH CONTINUES
TO BE FORECAST NORTHWEST OF HAWAII.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE SOUTHERN CONUS EAST OF THE
ROCKIES, WITH A NORTHWARD EXTENSION ACROSS THE OHIO VALLEY AND MOST OF THE
NORTHEAST AND MID-ATLANTIC REGION. THIS IS SUPPORTED BY THE REFORECAST
TEMPERATURE TOOLS, AND ALIGNS WELL WITH THE OVERALL SYNOPTIC PATTERN. A
LOW-AMPLITUDE TROUGH NEAR THE WEST COAST TILTS THE ODDS TOWARDS BELOW NORMAL
TEMPERATURES FOR THE WEST COAST STATES, THE NORTHERN ROCKIES, NORTHERN PLAINS,
AND UPPER MISSISSIPPI VALLEY. IN ALASKA, BELOW NORMAL TEMPERATURE CHANCES ARE
INCREASED OVER APPROXIMATELY THE SOUTHWESTERN QUARTER OF THE STATE, WITH ABOVE
NORMAL TEMPERATURE CHANCES ENHANCED OVER THE NORTH SLOPE, EASTERN PARTS OF THE
MAINLAND, AND THE PANHANDLE. THIS PATTERN IS CONSISTENT WITH THE MANUAL HEIGHT
BLEND FEATURES, AND MANY OF THE TEMPERATURE FORECAST TOOLS, ESPECIALLY RAW AND
BIAS-CORRECTED TEMPERATURES FROM THE VARIOUS ENSEMBLE MEANS. IN HAWAII, THE
PATTERN FORECASTED FOR THE 6-10 DAY PERIOD IS EXPECTED TO PERSIST THROUGH
WEEK-2, WITH ABOVE NORMAL TEMPERATURES FAVORED FOR KAUAI AND OAHU, AND NEAR
NORMAL TEMPERATURES FAVORED FOR MAUI AND THE BIG ISLAND.
ABOVE NORMAL PRECIPITATION IS FAVORED NEAR THE CANADIAN BORDER AND EXTENDING
SOUTHWARD ACROSS MOST OF THE CENTRAL AND EASTERN CONUS, CONSISTENT WITH THE
CONSOLIDATION AND AUTO PRECIPITATION TOOLS. BELOW NORMAL PRECIPITATION IS
FAVORED FROM NEVADA SOUTHEASTWARD ACROSS PORTIONS OF THE FOUR CORNERS REGION TO
FAR SOUTHWESTERN TEXAS, AND ALSO OVER FAR SOUTHERN TEXAS, ALSO SUPPORTED BY THE
CONSOLIDATION AND AUTO PRECIPITATION TOOLS. FOR HAWAII AND ALASKA,
PREDOMINANTLY WET CONDITIONS ARE FAVORED RELATIVE TO NORMAL WITH THE SAME
GENERAL SYNOPTIC FEATURES IN PLACE AS WAS THE CASE WITH THE 6-10 DAY OUTLOOK.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 35% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 35% 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: ABOVE AVERAGE, 4 OUT OF 5, WITH
GOOD RUN-TO-RUN CONTINUITY AMONG FORECAST MODELS, OFFSET BY DIFFERENCES BETWEEN
MODELS REGARDING STRENGTH AND POSITION OF VARIOUS SYNOPTIC FEATURES.
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
JUNE 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:
19660519 - 19990529 - 19920508 - 19890515 - 19980505
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:
19990528 - 19660520 - 20010522 - 19640425 - 19660515
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 22 - 26 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B N
SRN CALIF B N IDAHO B A NEVADA B N
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B N ARIZONA N N COLORADO N N
NEW MEXICO N B N DAKOTA B A S DAKOTA B A
NEBRASKA N A KANSAS N A OKLAHOMA A A
N TEXAS A A S TEXAS A N W TEXAS A B
MINNESOTA B A IOWA N A MISSOURI N A
ARKANSAS A A LOUISIANA A A WISCONSIN N 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 N MAINE A N
MASS A N CONN A N RHODE IS A N
PENN A A NEW JERSEY A N 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 B AK N SLOPE A A
AK ALEUTIAN B N AK WESTERN B A AK INT BSN A A
AK S INT B A AK SO COAST B A AK PNHDL N N
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 24 - 30 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B N OREGON B N NRN CALIF B N
SRN CALIF B N IDAHO B N NEVADA N B
W MONTANA B N E MONTANA B A WYOMING B N
UTAH N B ARIZONA N N COLORADO N N
NEW MEXICO A B N DAKOTA B A S DAKOTA B A
NEBRASKA N A KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A N W TEXAS A A
MINNESOTA B A IOWA N A MISSOURI A A
ARKANSAS A A LOUISIANA A A WISCONSIN B A
ILLINOIS N A MISSISSIPPI A A MICHIGAN N A
INDIANA N A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A A NEW YORK A N
VERMONT A N NEW HAMP A N MAINE A N
MASS N N CONN N N RHODE IS N N
PENN A A NEW JERSEY N N W VIRGINIA A A
MARYLAND N A DELAWARE N A VIRGINIA A A
N CAROLINA A A S CAROLINA A A GEORGIA A A
FL PNHDL A A FL PENIN A N AK N SLOPE A A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN A A
AK S INT B A AK SO COAST B N AK PNHDL A 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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