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FXUS06 KWBC 271925
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED AUGUST 27 2014

6-10 DAY OUTLOOK FOR SEP 02 - 06 2014

TODAY`S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA PATTERN 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
WEAK RIDGE OVER THE GULF OF ALASKA. DOWNSTREAM, NEGATIVE 500-HPA HEIGHT
ANOMALIES ARE EXPECTED OVER NORTHERN ALASKA SOUTHEASTWARD TO THE NORTHERN
ROCKIES AND NORTHERN PLAINS WITH A TROUGH FORECAST OVER THE NORTHWESTERN CONUS.
HOWEVER, THE 06Z OPERATIONAL GFS SOLUTION HAS THE TROUGH WITHDRAW WESTWARD WITH
NEGATIVE 500-HPA HEIGHT ANOMALIES OFF THE PACIFIC COAST. 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 THE INTERIOR BASIN OF
ALASKA IN ASSOCIATION WITH THE NEGATIVE 500-HPA HEIGHT ANOMALIES. ABOVE-NORMAL
TEMPERATURE PROBABILITIES FAVORED AREAS FOR WESTERN ALASKA, THE ALEUTIANS AND
THE PANHANDLE RELATED THE WEAK RIDGE DEVELOPMENT. BELOW-NORMAL TEMPERATURE
PROBABILITIES ARE ALSO ENHANCED FOR THE NORTHWESTERN CONUS NEAR THE TROUGH
FORECAST IN THIS REGION.  OFFSHORE WINDS FAVOR ABOVE NORMAL TEMPERATURES IN
CALIFORNIA. ALL FORECAST TOOLS ARE IN REASONABLY GOOD AGREEMENT ON THE FORECAST
TEMPERATURE PATTERN ACROSS THE CENTRAL AND EASTERN CONUS, WITH A MEAN FRONTAL
POSITION FORECAST FROM THE GREAT LAKES TOWARD THE SOUTHWESTERN U.S. ABOVE
NORMAL TEMPERATURES ARE FAVORED SOUTH OF THE FRONT, INCLUDING THE SOUTHERN
PLAINS, AND EASTERN U.S.

BELOW-MEDIAN PRECIPITATION CHANCES ARE ENHANCED FOR SOUTHERN ALASKA AND THE
ALEUTIANS RELATED TO THE PREDICTED RIDGE IN THE AREA, WHILE ABOVE-MEDIAN
PRECIPITATION IS FAVORED FOR NORTHERN ALASKA. BELOW-MEDIAN PRECIPITATION
CHANCES ARE ENHANCED FOR THE NORTHWESTERN CONUS EXCEPT THE NORTHERN ROCKIES AND
THE NORTHERN PLAINS CONSISTENT WITH NAEFS AND GEFS REFORECAST GUIDANCE. THE
FORECAST 500-HPA PATTERN IS NOT PARTICULARLY FAVORABLE FOR AN ACTIVE MONSOON,
INCREASING THE LIKELIHOOD FOR BELOW-MEDIAN PRECIPITATION IN THE SOUTHWEST. 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 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 20%
OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 20% OF YESTERDAY`S GFS
SUPERENSEMBLE MEAN CENTERED ON DAY 7, AND 20% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 7


MODEL OF THE DAY: NO PREFERENCE.

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 04 - 10 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. IN THE SOUTHERN TIER OF THE CONUS, MODEL ENSEMBLE MEAN SOLUTIONS ALSO
FORECAST A STRONG SUBTROPICAL RIDGE THERE. OVER THE ALASKA SECTOR, A CONSENSUS
OF THE ENSEMBLE MEAN SOLUTIONS FORECAST A 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 ROCKIES AND NORTHERN PLAINS IN ASSOCIATION WITH AN
EXPECTED TROUGH. ENHANCED PROBABILITIES OF NEAR- TO ABOVE-NORMAL TEMPERATURES
ARE FAVORED FOR MUCH OF THE NORTHEAST, SOUTHERN CONUS, AND CALIFORNIA
CONSISTENT WITH NAEFS GUIDANCE AND BIAS CORRECTED TEMPERATURES FROM THE 0Z
ECMWF ENSEMBLES. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF WESTERN
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 BROAD PARTS OF THE
NORTHWESTERN CONUS, THE GREAT BASIN AND SOUTHERN TEXAS CONSISTENT WITH NAEFS
AND GEFS REFORECAST GUIDANCE. THERE ARE ENHANCED PROBABILITIES OF NEAR- TO
BELOW-MEDIAN PRECIPITATION FOR SOUTHERN ALASKA AND THE PANHANDLE. NEAR- TO
ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR NORTHERN ALASKA.


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 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, 20% OF
YESTERDAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 10, 20% OF YESTERDAY`S 12Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, AND 10% OF YESTERDAY`S 12Z CANADIAN
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:
20020831 - 19520828 - 19800820 - 20020810 - 19510826


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:
19520829 - 19990904 - 20020830 - 20090817 - 19730806


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 02 - 06 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    N     OREGON      B    B     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       B    B     NEVADA      A    B
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    B
UTAH        B    B     ARIZONA     A    B     COLORADO    N    B
NEW MEXICO  A    B     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    A     KANSAS      A    A     OKLAHOMA    A    A
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    B
MINNESOTA   N    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   A    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    A     RHODE IS    A    N
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  N    A
AK ALEUTIAN A    B     AK WESTERN  A    B     AK INT BSN  B    A
AK S INT    B    B     AK SO COAST A    B     AK PNHDL    A    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 04 - 10 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    N     OREGON      N    B     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       B    B     NEVADA      N    B
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    B
UTAH        N    B     ARIZONA     N    N     COLORADO    N    N
NEW MEXICO  A    A     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    A     KANSAS      A    A     OKLAHOMA    A    A
N TEXAS     A    N     S TEXAS     A    B     W TEXAS     A    N
MINNESOTA   N    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   A    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    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  N    A
AK ALEUTIAN A    N     AK WESTERN  A    B     AK INT BSN  N    A
AK S INT    A    B     AK SO COAST A    B     AK PNHDL    A    B

                           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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