Prognostic Meteorological Discussion
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FXUS06 KWBC 201903
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON OCTOBER 20 2014

6-10 DAY OUTLOOK FOR OCT 26 - 30 2014

THE AVAILABLE MODELS EXHIBITED GOOD AGREEMENT ON THE 500-HPA HEIGHTS AND HEIGHT
ANOMALY PATTERNS. THE MODELS GENERALLY PREDICT ABOVE-NORMAL HEIGHTS OVER THE
ALEUTIANS, BELOW-NORMAL HEIGHTS NEAR THE PACIFIC NORTHWEST, AND WEAKLY
ABOVE-NORMAL HEIGHTS OVER MUCH OF THE CONUS, EXCEPT FOR FLORIDA. SOLUTIONS FROM
THE MODELS DISAGREE ON THE STRENGTH OF THE RIDGE/TROUGH COUPLET FROM THE
ALEUTIANS TO THE PACIFIC NORTHWEST. THE 0Z DETERMINISTIC EUROPEAN HAS THE LEAST
PROGRESSIVE PATTERN, WITH THE AREA OF BELOW-NORMAL HEIGHTS EXTENDING ONLY TO
WASHINGTON STATE. THE OTHER MODELS EXTEND THE BELOW-NORMAL HEIGHTS FARTHER
SOUTH TO OREGON OR CENTRAL CALIFORNIA. A WEAK TREND TOWARD HIGHER 500-HPA
HEIGHTS OVER THE SOUTHWEST WAS NOTED.

THE MANUAL BLEND WAS COMPRISED MAINLY OF ENSEMBLE MEANS (60 PERCENT).
YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN WAS GIVEN THE MOST WEIGHT AS THAT MODEL
HAD THE BEST COMBINED RANKING OF ANOMALY CORRELATION AND ANALOG CORRELATION
SCORE. YESTERDAY`S 12Z DETERMINISTIC EUROPEAN SOLUTION WAS INCLUDED TO ACCOUNT
FOR THAT POSSIBILITY. THE REMAINDER OF THE MANUAL BLEND WAS A MIXTURE OF THE
GFS SUPERENSEMBLE AND THE 6Z DETERMINISTIC GFS, TO CAPTURE THE TREND IN RISING
HEIGHTS OVER THE SOUTHWEST.

ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER MOST OF THE CONUS WITH UPPER-LEVEL
HEIGHTS BEING NEAR TO ABOVE-NORMAL AND SURFACE HIGH PRESSURE ACROSS MUCH OF THE
CONUS. NEAR NORMAL TEMPERATURES ARE LIKELY OVER THE PACIFIC NORTHWEST AND
PORTIONS OF THE GREAT BASIN WITH NEAR-NORMAL 500-HPA HEIGHTS AND WESTERLY FLOW.
LOW-LEVEL SOUTHWEST FLOW FAVORS ABOVE-NORMAL TEMPERATURES FOR WESTERN ALASKA
WHILE HIGH PRESSURE CAN ALLOW FOR COLDER AIR TO FLOW INTO THE ALASKA PANHANDLE.

THE TROUGH NEAR THE PACIFIC NORTHWEST FAVORS ABOVE-MEDIAN PRECIPITATION FROM
NORTHERN CALIFORNIA AND THE PACIFIC NORTHWEST TO THE NORTHERN GREAT PLAINS.
BELOW-MEDIAN PRECIPITATION, DUE TO ANOMALOUS 500-HPA RIDGING AND SURFACE HIGH
PRESSURE, IS FAVORED FROM THE SOUTHWEST TO THE GULF COAST, NORTHEASTWARD TO NEW
ENGLAND. BELOW-NORMAL HEIGHTS AND A FEED OF TROPICAL MOISTURE FAVOR
ABOVE-MEDIAN RAINFALL AMOUNTS OVER FLORIDA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S GFS SUPERENSEMBLE
MEAN CENTERED ON DAY 8, 20% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8,
40% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, AND 20% OF
YESTERDAY`S OPERATIONAL 12Z ECMWF CENTERED ON DAY 7


MODEL OF THE DAY: YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG VARIOUS DYNAMICAL AND STATISTICAL TOOLS.

8-14 DAY OUTLOOK FOR OCT 28 - NOV 03, 2014

MODEL FORECASTS OF 500-HPA HEIGHTS VARY CONSIDERABLY MORE IN THE 8-14 DAY
TIMEFRAME COMPARED TO THE 6-10 DAY TIMEFRAME. ANOMALIES PREDICTED BY THE MODELS
ARE GENERALLY WEAK, RESULTING IN A POORLY SPECIFIED CIRCULATION PATTERN. MOST
MODEL SOLUTIONS DEPICT BELOW-NORMAL HEIGHTS NEAR THE PACIFIC NORTHWEST, WITH
THE GFS BASED SOLUTIONS EXTENDING THAT FEATURE EASTWARD, WHILE THE EUROPEAN AND
CANADIAN ENSEMBLE MEANS KEEP THE FEATURE NEAR THE COAST. GENERALLY,
ABOVE-NORMAL HEIGHTS ARE PREDICTED OVER THE REST OF THE CONUS AND ALASKA.

THE LARGEST CONSTITUENT OF 500-HPA MANUAL BLEND WAS THE 6Z GFS ENSEMBLE MEAN,
AS THAT MODEL HAD THE HIGHEST RANKING OF ANOMALY CORRELATION AND ANALOG
CORRELATION. THE PATTERN IN THE OTHER CONSTITUENT MODELS WAS SIMILAR, EXCEPT
FOR THE 6Z DETERMINISTIC GFS WHICH EXTENDS THE BELOW-NORMAL HEIGHTS ALL THE WAY
ALONG THE U.S.-CANADIAN BORDER.

ABOVE-NORMAL TEMPERATURES ARE GENERALLY FAVORED FOR MUCH OF THE CONUS DUE TO
PREDICTED ABOVE-NORMAL HEIGHTS AND SURFACE HIGH PRESSURE. THE GFS SUPERENSEMBLE
AND THE 0Z ECMWF ENSEMBLE MEAN DO NOT INDICATE A SINGLE LOW-PRESSURE CENTER AT
THE SURFACE IN THE 7-DAY MEAN SEA-LEVEL PRESSURE FIELD OVER THE CONUS, WHILE
OTHER MODELS DEPICT A SMALL AREA OF LOWER PRESSURES OVER THE CENTRAL PLAINS.
BELOW-NORMAL TEMPERATURES ARE FAVORED OVER THE PORTIONS OF THE ALASKA PANHANDLE
PREDICTED TO BE UNDER EASTERLY FLOW, WHILE WESTERN ALASKA WILL LIKELY
EXPERIENCE ABOVE-NORMAL TEMPERATURES.

ABOVE-MEDIAN PRECIPITATION IS FAVORED ACROSS WESTERN ALASKA DUE TO
SOUTHWESTERLY FLOW AT THE SURFACE AND AN ACTIVE STORM TRACK ACROSS THE
ALEUTIANS. THE TROUGH NEAR THE PACIFIC NORTHWEST FAVORS ABOVE-MEDIAN RAINS FROM
THE PACIFIC NORTHWEST TO THE CENTRAL AND NORTHERN GREAT PLAINS. MODELS INDICATE
A MOIST FLOW FROM THE SOUTH ACROSS THE GREAT PLAINS, CONSISTENT WITH A RIDGE
OVER THE EASTERN CONUS.  BELOW-MEDIAN PRECIPITATION AMOUNTS ARE LIKELY ACROSS
THE SOUTHEAST AND SOUTHWEST, SUPPORTED BY THE PREDICTED ABOVE-NORMAL 500-HPA
HEIGHTS OVER THOSE REGIONS

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 40% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11,
15% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 30% 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: MATT ROSENCRANS

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
NOVEMBER 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:
19841008 - 19791024 - 19631011 - 19531009 - 19541019


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:
19531011 - 19791024 - 19841006 - 19901027 - 19631011


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 26 - 30 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 28 - NOV 03, 2014

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