Prognostic Meteorological Discussion
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FXUS06 KWBC 291901
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI AUGUST 29 2014

6-10 DAY OUTLOOK FOR SEP 04 - 08 2014

TODAY`S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA PATTERN HEIGHT
FORECAST FOR THE 6-10 DAY PERIOD. ALL MODELS ARE FORECASTING POSITIVE 500-HPA
HEIGHT ANOMALIES OVER THE FAR NORTHERN PACIFIC, EXTENDING ACROSS THE ALEUTIANS
TO A RIDGE OVER THE GULF OF ALASKA. DOWNSTREAM, NEGATIVE 500-HPA HEIGHT
ANOMALIES ARE EXPECTED OVER THE NORTHERN ROCKIES AND NORTHERN PLAINS WITH A
TROUGH FORECAST JUST INLAND OF THE PACIFIC COAST. POSITIVE 500-HPA HEIGHT
ANOMALIES ARE EXPECTED OVER THE EASTERN CONUS. THE ENSEMBLE SPAGHETTI DIAGRAMS
INDICATE MODERATE SPREAD ACROSS THE FORECAST DOMAIN. IN THE SOUTHERN TIER OF
THE CONUS, MODEL ENSEMBLE MEAN SOLUTIONS FORECAST A STRONG SUBTROPICAL RIDGE
THERE.

BELOW-NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED FOR NORTHEASTERN ALASKA IN
ASSOCIATION WITH NEGATIVE 500-HPA HEIGHT ANOMALIES. ABOVE-NORMAL TEMPERATURE
PROBABILITIES ARE FAVORED FOR THE REST OF ALASKA, THE ALEUTIANS AND THE
PANHANDLE RELATED TO RIDGING. BELOW-NORMAL TEMPERATURE PROBABILITIES ARE
ENHANCED FOR THE NORTHWESTERN AND NORTH-CENTRAL CONUS IN PROXIMITY TO THE THE
FORECAST TROUGH OVER THE AREA. ALL FORECAST TOOLS ARE IN REASONABLY GOOD
AGREEMENT ON THE FORECAST TEMPERATURE PATTERN ACROSS THE EASTERN AND SOUTHERN
CONUS, WITH FORECAST POSITIVE 500-HPA HEIGHT ANOMALIES FROM THE GREAT LAKES
TOWARD THE SOUTHWESTERN U.S. ABOVE NORMAL TEMPERATURES ARE FAVORED SOUTH OF THE
MEAN FRONTAL BOUNDARY, ESPECIALLY ACROSS THE SOUTHERN PLAINS, AND SOUTHEAST.

ABOVE-MEDIAN PRECIPITATION CHANCES ARE ENHANCED FOR ALASKA AND THE ALEUTIANS,
RELATED TO THE PREDICTED LOWER-LEVEL SOUTHWESTERLY FLOW OVER THE AREA.
BELOW-MEDIAN PRECIPITATION CHANCES ARE ENHANCED FOR THE NORTHWESTERN CONUS
EXTENDING TO THE CENTRAL ROCKIES AND THE SOUTHERN PLAINS, CONSISTENT WITH NAEFS
AND GEFS REFORECAST GUIDANCE. WITH NEGATIVE HEIGHT ANOMALIES CENTERED OVER THE
NORTHERN PLAINS, ABOVE-MEDIAN PRECIPITATION IS FAVORED ALONG AND EAST OF THE
ANOMALOUS TROUGH AXIS ASSOCIATED WITH AN ACTIVE STORM TRACK.


TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 40% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, AND
40% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: TODAY`S GFS SUPER-ENSEMBLE MEAN AND TODAY`S 0Z ECMWF ENSEMBLE
MEAN ARE TIED

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE MODELS AND TOOLS

8-14 DAY OUTLOOK FOR SEP 06 - 12 2014

THE ENSEMBLE MEAN PREDICTIONS ON THE 500-HPA HEIGHT PATTERN FOR THE WEEK-2
PERIOD ARE IN FAIR AGREEMENT OVER NORTH AMERICA. A TROUGH IS PREDICTED OVER THE
PACIFIC NORTHWEST, AND WEAK 500-HPA HEIGHT ANOMALIES ARE FORECAST OVER THE
CONUS. OVER THE SOUTHERN TIER OF THE CONUS, MODEL ENSEMBLE MEAN SOLUTIONS
CONTINUE TO FORECAST A STRONG SUBTROPICAL RIDGE THERE. OVER THE ALASKA SECTOR,
A CONSENSUS OF THE ENSEMBLE MEAN SOLUTIONS FORECAST A WEAK RIDGE OVER THE GULF
OF ALASKA WITH POSITIVE 500-HPA HEIGHT ANOMALIES OVER THE STATE.

THERE ARE ENHANCED PROBABILITIES FOR NEAR- TO BELOW-NORMAL TEMPERATURES FOR
SOME AREAS OF THE NORTHERN PLAINS, THE UPPER-MISSISSIPPI RIVER VALLEY AND THE
GREAT LAKES REGIONS IN ASSOCIATION WITH AN EXPECTED TROUGH. ENHANCED
PROBABILITIES OF NEAR- TO ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE
SOUTHERN CONUS, AND WEST COAST CONSISTENT WITH NAEFS GUIDANCE AND BIAS
CORRECTED TEMPERATURES FROM THE 0Z ECMWF ENSEMBLES. ABOVE-NORMAL TEMPERATURES
ARE FAVORED FOR MUCH OF SOUTHWESTERN ALASKA INCLUDING THE ALEUTIANS AND THE
PANHANDLE.

ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE CENTRAL AND EASTERN CONUS
IN ASSOCIATION WITH THE FORECAST TROUGH IN CENTRAL NORTH AMERICA. NEAR- TO
BELOW-MEDIAN PRECIPITATION PROBABILITIES ARE ENHANCED FOR PARTS OF THE
NORTHWESTERN CONUS, AND THE GREAT BASIN CONSISTENT WITH NAEFS AND GEFS
REFORECAST GUIDANCE. THERE ARE ENHANCED PROBABILITIES OF NEAR- TO ABOVE-MEDIAN
PRECIPITATION FOR ALASKA, THE ALEUTIANS AND THE PANHANDLE.


THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, 20% OF
YESTERDAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 10, AND 20% OF YESTERDAY`S
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO REASONABLE AGREEMENT AMONG MODEL TOOLS, OFFSET BY A LOW-AMPLITUDE FORECAST
PATTERN

FORECASTER: QIN GINGER ZHANG

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
SEPTEMBER 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:
20050824 - 20060826 - 20010905 - 19830903 - 19620908


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:
20050821 - 19980815 - 19620909 - 20060826 - 20050826


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 04 - 08 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    B     OREGON      B    B     NRN CALIF   N    B
SRN CALIF   N    N     IDAHO       B    B     NEVADA      N    B
W MONTANA   B    N     E MONTANA   B    A     WYOMING     B    A
UTAH        N    B     ARIZONA     A    N     COLORADO    N    N
NEW MEXICO  A    N     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    A     KANSAS      A    A     OKLAHOMA    A    N
N TEXAS     A    B     S TEXAS     A    N     W TEXAS     A    B
MINNESOTA   B    A     IOWA        A    A     MISSOURI    A    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    A     MAINE       A    A
MASS        A    A     CONN        A    A     RHODE IS    A    N
PENN        A    A     NEW JERSEY  A    A     W VIRGINIA  A    A
MARYLAND    A    A     DELAWARE    A    N     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  B    A
AK ALEUTIAN A    N     AK WESTERN  A    N     AK INT BSN  N    A
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    A    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 06 - 12 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    B     OREGON      N    B     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       N    B     NEVADA      N    B
W MONTANA   N    N     E MONTANA   B    A     WYOMING     N    N
UTAH        N    B     ARIZONA     N    A     COLORADO    N    A
NEW MEXICO  A    A     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    A     KANSAS      A    A     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   B    A     IOWA        N    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   B    A
ILLINOIS    A    A     MISSISSIPPI A    A     MICHIGAN    N    A
INDIANA     A    A     OHIO        A    A     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    A     NEW YORK    N    A
VERMONT     N    A     NEW HAMP    N    A     MAINE       N    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    N     AK N SLOPE  N    A
AK ALEUTIAN A    A     AK WESTERN  A    N     AK INT BSN  N    A
AK S INT    A    N     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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