956
FXUS06 KWBC 221942
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON JULY 22 2024
6-10 DAY OUTLOOK FOR JUL 28 - AUG 01, 2024
THERE IS GOOD AGREEMENT ON THE 500-HPA HEIGHT FORECAST ACROSS NORTH AMERICA
BETWEEN THE 0Z ENSEMBLE MEAN SOLUTIONS OF THE ECMWF, GEFS AND CANADIAN MODELS
WITH ONLY SMALL DIFFERENCES AMONG THE HEIGHT FORECASTS. A MID-LEVEL TROUGH OVER
THE WESTERN CONTIGUOUS U.S. (CONUS) AT THE START OF THE PERIOD DEAMPLIFIES OVER
TIME, WHILE A RIDGE OVER THE NORTHEASTERN CONUS AND ASSOCIATED POSITIVE 500-HPA
HEIGHT ANOMALIES SPREAD WESTWARD TO COVER MOST OF THE CONUS. THE GEFS ENSEMBLE
MEAN MAINTAINS WEAK RELATIVE TROUGHING AND NEAR AVERAGE 500-HPA HEIGHTS OVER
THE NORTHWESTERN CONUS LATE IN THE PERIOD, WHILE THE ECMWF MODEL PREDICTS WEAK
POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE WEST AND NEAR AVERAGE HEIGHTS OVER
THE SOUTHEASTERN CONUS. MOST MODEL SOLUTIONS PREDICT CYCLONIC FLOW OVER MOST OF
ALASKA AHEAD OF A BROAD TROUGH CENTERED TO THE WEST OF THE STATE. NEGATIVE
500-HPA HEIGHT ANOMALIES ARE FORECAST OVER THE MAINLAND AND POSITIVE ANOMALIES
ARE PREDICTED TO THE SOUTH OF THE STATE. WEAK POSITIVE 500-HPA HEIGHT ANOMALIES
ARE PREDICTED OVER HAWAII BY THE ECMWF ENSEMBLE MEAN, WHILE NEAR AVERAGE
500-HPA HEIGHTS ARE PREDICTED OVER HAWAII BY THE GEFS.
BELOW-NORMAL TEMPERATURES ARE LIKELY OVER MOST OF ALASKA EXCEPT FOR THE WESTERN
AND CENTRAL ALEUTIANS, UNDER NEGATIVE 500-HPA HEIGHT ANOMALIES. NEAR-NORMAL
TEMPERATURES ARE FAVORED OVER WEST COAST STATES OF THE CONUS, WITH A
DEAMPLIFYING TROUGH OVER THE REGION. BELOW-NORMAL TEMPERATURES ARE SLIGHTLY
FAVORED FOR PARTS OF SOUTHERN CALIFORNIA, CONSISTENT WITH THE TEMPERATURE
CONSOLIDATION TOOL. NEAR-NORMAL TEMPERATURES ARE FAVORED OVER MOST OF THE
SOUTHEASTERN CONUS, WHERE TEMPERATURE FORECASTS FROM THE ECMWF AND GEFS ARE
LESS CONSISTENT. BELOW-NORMAL TEMPERATURES ARE FAVORED FOR SOUTHERN TEXAS,
WHILE ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE EASTERN GULF COAST,
CONSISTENT WITH THE TEMPERATURE CONSOLIDATION TOOL. ABOVE-NORMAL TEMPERATURES
ARE LIKELY ACROSS THE REMAINDER OF THE CONUS, AS POSITIVE 500-HPA HEIGHT
ANOMALIES SPREAD WESTWARD OVER THE ENTIRE CONUS DURING THE PERIOD. NEAR-NORMAL
TEMPERATURES ARE FAVORED FOR HAWAII, UNDER WEAK MID-LEVEL HEIGHT ANOMALIES.
ABOVE-NORMAL PRECIPITATION IS FAVORED ACROSS ALASKA, UNDER ENHANCED ONSHORE
FLOW OR CYCLONIC FLOW. ABOVE-NORMAL PRECIPITATION IS FAVORED FOR PARTS OF THE
PACIFIC NORTHWEST, AHEAD OF RELATIVE TROUGHING DURING THE PERIOD. BELOW-NORMAL
PRECIPITATION IS FAVORED OVER A LARGE AREA OF THE WESTERN HALF OF THE CONUS,
CONSISTENT WITH MOST DYNAMICAL MODEL FORECASTS. ABOVE-NORMAL PRECIPITATION IS
FAVORED OVER SOUTHEASTERN TEXAS CONSISTENT WITH THE PRECIPITATION CONSOLIDATION
TOOL. ABOVE-NORMAL PRECIPITATION IS SLIGHTLY FAVORED OVER MUCH OF THE EASTERN
HALF OF THE CONUS, OUTSIDE THE NORTHEAST, CONSISTENT WITH MOST DYNAMICAL MODEL
PRECIPITATION TOOLS. NEAR-TO-BELOW-NORMAL PRECIPITATION IS FAVORED FOR THE
NORTHEAST, CONSISTENT WITH THE CONSOLIDATION. THE ECMWF MODEL FORECAST FAVORS
DRIER CONDITIONS IN THIS AREA RELATIVE TO THE GEFS MODEL FORECAST. NEAR-NORMAL
PRECIPITATION IS FAVORED ACROSS HAWAII, AS PREDICTED BY THE AUTO PRECIPITATION
FORECAST TOOL.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 35% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
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: ABOVE-AVERAGE, 4 OUT OF 5, DUE TO
GOOD GENERAL AGREEMENT AMONG THE DYNAMICAL MODEL HEIGHT FORECASTS AND TOOLS,
OFFSET BY DIFFERENCES IN TEMPERATURE AND PRECIPITATION TOOLS FOR SOME AREAS.
8-14 DAY OUTLOOK FOR JUL 30 - AUG 05, 2024
THE WEEK-2 MANUAL BLEND AND THE ECMWF, GEFS AND CANADIAN ENSEMBLE MEAN
FORECASTS PREDICT POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE ALEUTIAN ISLANDS
AND ACROSS THE ENTIRE CONUS, WITH NEGATIVE 500-HPA HEIGHT ANOMALIES PREDICTED
OVER MAINLAND AND SOUTHEAST ALASKA. CYCLONIC FLOW AHEAD OF A TROUGH CONTINUES
OVER MOST OF ALASKA, WHILE A RIDGE IS PREDICTED OVER THE CONUS IN EACH ENSEMBLE
MEAN.
NEARLY COAST-TO-COAST LIKELY ABOVE-NORMAL TEMPERATURES ARE PREDICTED ACROSS THE
CONUS, UNDER A RIDGE AND CONSISTENT WITH MOST DYNAMICAL MODEL TEMPERATURE
TOOLS. A SMALL AREA OF FAVORED NEAR-NORMAL TEMPERATURES IS FORECAST FOR PARTS
OF SOUTH TEXAS. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN
ALEUTIANS, UNDER PREDICTED POSITIVE 500-HPA HEIGHT ANOMALIES, WHILE
BELOW-NORMAL TEMPERATURES ARE FAVORED FOR MAINLAND AND SOUTHEAST ALASKA, UNDER
PREDICTED NEGATIVE 500-HPA HEIGHT ANOMALIES IN THE MANUAL BLEND AND MOST
DYNAMICAL MODEL FORECASTS. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR WESTERN
ISLANDS OF HAWAII, UNDER WEAK POSITIVE 500-HPA HEIGHT ANOMALIES.
ABOVE-NORMAL PRECIPITATION CONTINUES TO BE FAVORED FOR THE EASTERN ALEUTIANS,
MAINLAND ALASKA, AND SOUTHEAST ALASKA, UNDER ENHANCED ONSHORE AND CYCLONIC
FLOW. ABOVE-NORMAL PRECIPITATION CONTINUES TO BE SLIGHTLY FAVORED FOR SOME
AREAS OF THE PACIFIC NORTHWEST, AHEAD OF A WEAK RELATIVE TROUGH. BELOW-NORMAL
PRECIPITATION IS FAVORED ACROSS MOST OF THE WESTERN CONUS IN WEEK-2, UNDER THE
PREDICTED BROAD RIDGE. ABOVE-NORMAL PRECIPITATION IS SLIGHTLY FAVORED OVER MOST
OF THE EASTERN CONUS AND ALONG THE ENTIRE GULF COAST, WHERE PRECIPITATION TOOLS
ARE RELATIVELY CONSISTENT. NEAR-NORMAL PRECIPITATION IS FAVORED ACROSS HAWAII,
AS PREDICTED BY THE AUTO PRECIPITATION FORECAST TOOL.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 35% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 40% 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: ABOUT-AVERAGE, 3 OUT OF 5, DUE TO
GOOD GENERAL AGREEMENT AMONG THE DYNAMICAL MODEL HEIGHT FORECASTS AND TOOLS,
OFFSET BY DIFFERENCES IN TEMPERATURE AND PRECIPITATION TOOLS FOR SOME AREAS AND
AN EVOLVING CIRCULATION PATTERN.
FORECASTER: D COLLINS
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
AUGUST 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:
19980801 - 20030720 - 19980707 - 20020710 - 20060704
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:
19980801 - 19890715 - 19980706 - 20060703 - 20030720
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 28 - AUG 01, 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N A OREGON N N NRN CALIF N N
SRN CALIF B B IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A B
UTAH A B ARIZONA A B COLORADO A B
NEW MEXICO A B N DAKOTA A N S DAKOTA A N
NEBRASKA A N KANSAS A N OKLAHOMA A A
N TEXAS N A S TEXAS B A W TEXAS A B
MINNESOTA A A IOWA A A MISSOURI A A
ARKANSAS N A LOUISIANA N A WISCONSIN A A
ILLINOIS A A MISSISSIPPI N A MICHIGAN A A
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA N A NEW YORK A N
VERMONT A N NEW HAMP A N MAINE A N
MASS A N CONN A N RHODE IS A N
PENN A N NEW JERSEY A N W VIRGINIA A A
MARYLAND A N DELAWARE A N VIRGINIA A N
N CAROLINA N A S CAROLINA N A GEORGIA N A
FL PNHDL A A FL PENIN A A AK N SLOPE B A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL B A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 30 - AUG 05, 2024
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A A OREGON A N NRN CALIF A N
SRN CALIF A N IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A B
UTAH A B ARIZONA A B COLORADO A B
NEW MEXICO A B N DAKOTA A N S DAKOTA A B
NEBRASKA A B KANSAS A B OKLAHOMA A N
N TEXAS A N S TEXAS N A W TEXAS A N
MINNESOTA A N IOWA A N MISSOURI A N
ARKANSAS A N LOUISIANA A A WISCONSIN A N
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 A
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 B A
AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL B 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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page