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FXUS06 KWBC 221902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU JUNE 22 2017

6-10 DAY OUTLOOK FOR JUN 28 - JUL 02, 2017

TODAY`S MODELS EXHIBIT FAIR AGREEMENT IN THE PREDICTED 500-HPA HEIGHT PATTERN.
A WEAK TROUGH IS PREDICTED OVER NORTHEASTERN NORTH AMERICA WHICH EXTENDS INTO
THE EASTERN CONUS. WEAK RIDGING IS INDICATED UPSTREAM OVER THE ROCKIES WHILE A
WEAK TROUGH IS FORECAST NEAR THE PACIFIC NORTHWEST COAST. FOR ALASKA, RIDGING
AND ABOVE NORMAL HEIGHTS ARE FORECAST ACROSS ALL BUT WESTERN ALASKA, WHERE
TROUGHING AND BELOW NORMAL HEIGHTS ARE ANTICIPATED. THE 0Z ECMWF ENSEMBLE MEAN,
0Z GFS ENSEMBLE MEAN, AND THE 0Z CANADIAN ENSEMBLE MEAN RECEIVED THE GREATEST
WEIGHTS IN TODAY`S 500-HPA MANUAL HEIGHT BLEND DUE TO ANALYSIS OF ANALOG
CORRELATIONS (WHICH MEASURE HOW CLOSELY THE FORECAST PATTERN MATCHES CASES THAT
HAVE OCCURRED IN THE PAST) AND RECENT SKILL (BASED ON ANOMALY CORRELATIONS OF
THE 500-HPA PATTERN DURING THE LAST 60 DAYS).

BELOW NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE EASTERN HALF OF THE CONUS
IN ASSOCIATION WITH A MEAN TROUGH OVER NORTHEASTERN NORTH AMERICA CONSISTENT
WITH THE GEFS AND ECMWF BIAS-CORRECTED TEMPERATURE FORECAST TOOLS. RIDGING
AND/OR ABOVE NORMAL HEIGHTS LEAD TO ENHANCED PROBABILITIES FOR NEAR TO ABOVE
NORMAL TEMPERATURES FOR MUCH OF THE WESTERN CONUS AND ALASKA.

RIDGING OVER EASTERN ALASKA FAVORS GENERALLY DRIER THAN NORMAL CONDITIONS FOR
PARTS OF EASTERN MAINLAND ALASKA, WHILE MOIST FLOW AROUND THE WEST SIDE OF THE
RIDGE SUPPORTS ABOVE MEDIAN PRECIPITATION ACROSS PARTS OF WESTERN ALASKA AND
THE ALEUTIANS. TROUGHING OVER NORTHEASTERN NORTH AMERICA LEADS TO INCREASED
CHANCES FOR ABOVE MEDIAN PRECIPITATION FOR PARTS OF THE NORTHERN PLAINS, THE
UPPER AND MIDDLE MISSISSIPPI VALLEY, GREAT LAKES, OHIO VALLEY, AND NORTHEAST.
ENHANCED PROBABILITIES FOR BELOW MEDIAN PRECIPITATION ARE INDICATED FOR PARTS
OF THE SOUTHEAST, THE EASTERN TENNESSEE VALLEY, AND THE MIDDLE ATLANTIC, WHICH
IS CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GEFS AND ECMWF ENSEMBLE
MEMBERS. BELOW MEDIAN PRECIPITATION IS ALSO FAVORED FOR THE PACIFIC NORTHWEST
AND THE NORTHERN GREAT BASIN DUE TO A LOW-AMPLITUDE RIDGE AND POSITIVE HEIGHT
ANOMALIES MOVING INTO THE AREA FROM THE WEST.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 25% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 25% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 10% 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: AVERAGE, 3 OUT OF 5, DUE TO FAIR
MODEL AGREEMENT.

8-14 DAY OUTLOOK FOR JUN 30 - JUL 06, 2017

DURING THE WEEK-2 PERIOD, MOST MODEL RUNS CONTINUE TO PREDICT A TROUGH NEAR THE
PACIFIC NORTHWEST COAST, A WEAK RIDGE CENTERED NEAR THE HIGH PLAINS, AND A
DEAMPLIFYING TROUGH CENTERED NEAR THE GREAT LAKES. TODAY`S WEEK-2 MANUAL
500-HPA HEIGHT BLEND IS WEIGHTED MOST HEAVILY TOWARD THE ENSEMBLE MEAN SOLUTION
FROM THE 0Z ECMWF DUE TO SUPERIOR SKILL OVER THE PAST 60 DAYS. THE RESULTING
500-HPA PATTERN FEATURES VERY WEAK ANOMALIES OVER ALMOST THE ENTIRE DOMAIN
LEADING TO A LOW CONFIDENCE FORECAST.

TROUGHING OVER THE GREAT LAKES LEADS TO ENHANCED PROBABILITIES FOR BELOW NORMAL
TEMPERATURES FOR PARTS OF THE UPPER MISSISSIPPI VALLEY AND THE GREAT LAKES.
MEAN SOUTHWESTERLY LOW LEVEL FLOW SUPPORTS ABOVE NORMAL TEMPERATURES FOR THE
SOUTHERN ROCKIES AND SOUTHERN PLAINS. ABOVE AVERAGE TEMPERATURES ARE SLIGHTLY
FAVORED FOR PORTIONS OF THE SOUTHEAST AND THE MIDDLE ATLANTIC CONSISTENT WITH
CALIBRATED ECMWF GUIDANCE. RIDGING LEADS TO INCREASED CHANCES FOR ABOVE NORMAL
TEMPERATURES ACROSS EASTERN ALASKA AND WASHINGTON STATE.

ABOVE MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE NORTHERN PLAINS, MOST OF
THE MISSISSIPPI VALLEY, GREAT LAKES, NORTHEAST, MID-ATLANTIC, AND THE OHIO AND
TENNESSEE VALLEYS UNDERNEATH CYCLONIC FLOW. SURFACE HIGH PRESSURE SUPPORTS
DRIER THAN NORMAL CONDITIONS FOR PARTS OF CAROLINA. NEAR TO BELOW MEDIAN
PRECIPITATION IS FAVORED FOR THE NORTHWEST, THE GENERAL VICINITY OF THE
ROCKIES, GENERALLY ASSOCIATED WITH 500-HPA RIDGING AND/OR ABOVE-NORMAL HEIGHTS.
ABOVE MEDIAN PRECIPITATION IS FAVORED FOR ALASKA CONSISTENT WITH PRECIPITATION
ESTIMATES FROM THE GEFS ENSEMBLE MEMBERS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, 10% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 30% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: MUCH BELOW AVERAGE, 1 OUT OF 5,
DUE TO WEAK MEAN 500-HPA ANOMALIES IN THE MANUAL BLEND ACROSS MUCH OF THE
FORECAST DOMAIN AND LARGE DISAGREEMENTS AMONG THE SURFACE SPECIFICATION TOOLS.

FORECASTER: LUKE H

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 1981-2010 BASE PERIOD MEANS FOR
TEMPERATURE...PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN
THE CLIMATE OUTLOOKS.

THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON
JULY 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:
19810624 - 19670701 - 19770627 - 20020605 - 19610624


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:
19810623 - 19670630 - 19770627 - 19680619 - 19600615


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 28 - JUL 02, 2017

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     OREGON      A    B     NRN CALIF   A    N
SRN CALIF   N    N     IDAHO       N    B     NEVADA      A    N
W MONTANA   N    N     E MONTANA   N    N     WYOMING     N    N
UTAH        A    N     ARIZONA     A    N     COLORADO    A    N
NEW MEXICO  A    N     N DAKOTA    N    A     S DAKOTA    A    A
NEBRASKA    A    A     KANSAS      A    N     OKLAHOMA    N    N
N TEXAS     N    N     S TEXAS     N    N     W TEXAS     A    N
MINNESOTA   B    A     IOWA        N    A     MISSOURI    B    A
ARKANSAS    B    N     LOUISIANA   B    N     WISCONSIN   B    A
ILLINOIS    B    A     MISSISSIPPI B    N     MICHIGAN    B    A
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    N
TENNESSEE   B    B     ALABAMA     B    B     NEW YORK    B    A
VERMONT     B    A     NEW HAMP    B    A     MAINE       N    A
MASS        B    N     CONN        B    N     RHODE IS    B    N
PENN        N    A     NEW JERSEY  B    N     W VIRGINIA  B    N
MARYLAND    B    N     DELAWARE    B    N     VIRGINIA    B    B
N CAROLINA  B    B     S CAROLINA  B    B     GEORGIA     B    B
FL PNHDL    B    N     FL PENIN    N    N     AK N SLOPE  A    A
AK ALEUTIAN A    A     AK WESTERN  A    A     AK INT BSN  A    N
AK S INT    N    A     AK SO COAST N    A     AK PNHDL    N    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 30 - JUL 06, 2017

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    N     OREGON      N    N     NRN CALIF   N    N
SRN CALIF   N    N     IDAHO       N    B     NEVADA      N    N
W MONTANA   N    N     E MONTANA   N    N     WYOMING     N    N
UTAH        N    B     ARIZONA     N    N     COLORADO    N    B
NEW MEXICO  A    B     N DAKOTA    N    A     S DAKOTA    N    A
NEBRASKA    N    N     KANSAS      N    N     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   N    A     IOWA        N    A     MISSOURI    N    A
ARKANSAS    N    N     LOUISIANA   N    N     WISCONSIN   B    A
ILLINOIS    N    A     MISSISSIPPI N    N     MICHIGAN    B    A
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    A     ALABAMA     N    N     NEW YORK    B    A
VERMONT     N    A     NEW HAMP    N    A     MAINE       N    A
MASS        N    A     CONN        N    A     RHODE IS    N    A
PENN        N    A     NEW JERSEY  N    A     W VIRGINIA  N    A
MARYLAND    N    A     DELAWARE    N    N     VIRGINIA    N    N
N CAROLINA  A    N     S CAROLINA  A    B     GEORGIA     A    N
FL PNHDL    A    N     FL PENIN    A    N     AK N SLOPE  A    A
AK ALEUTIAN N    A     AK WESTERN  N    A     AK INT BSN  A    A
AK S INT    N    A     AK SO COAST N    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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