Prognostic Meteorological Discussion
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FXUS06 KWBC 211940
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE OCTOBER 21 2014

6-10 DAY OUTLOOK FOR OCT 27 - 31 2014

THE AVAILABLE MODELS FROM TODAY EXHIBIT GOOD AGREEMENT, WITH THE EXCEPTION OF
THE 0Z DETERMINISTIC ECMWF. THE OVERALL PATTERN SHOWS A TROUGH OFF THE WEST
COAST AND A WEAK TROUGH OVER THE CENTRAL CONUS, WITH RIDGING OVER THE EASTERN
THIRD OF THE LOWER 48 STATES. ABOVE-NORMAL 500-HPA HEIGHTS ARE PREDICTED BY
MOST MODELS OVER WESTERN AND CENTRAL ALASKA, WITH THE 0Z DETERMINISTIC ECMWF
SOLUTION SLIGHTLY FURTHER WEST WITH THE RIDGE AXIS.

THE 500-HPA MANUAL HEIGHT BLEND`S LARGEST CONSTITUENT WAS THE 0Z EUROPEAN
ENSEMBLE MEAN AS THAT MODEL HAS THE BEST COMBINED RANKING OF ANOMALY
CORRELATION OF THE MOST RECENT 60 DAYS AND ANALOG CORRELATION. THE 0Z GFS
ENSEMBLE MEAN WAS THE SECOND LARGEST COMPONENT, AS THAT MODEL HAS THE BEST
COMBINED SCORE AMONG THE GFS BASED SOLUTIONS. THE 6Z DETERMINISTIC AND ENSEMBLE
MEAN, AND THE CANADIAN ENSEMBLE MEAN WERE EXCLUDED DUE TO PROBLEMS WITH
SATELLITE DATA INGEST FROM SOME POES AND GOES SYSTEMS. THE ISSUE IS NOT
SUSPECTED TO HAVE IMPACTED THE ECMWF MODEL RUNS.

TELECONNECTIONS ON A POSITIVE HEIGHT ANOMALY CENTER JUST SOUTH OF THE ALEUTIANS
YIELD A PATTERN SIMILAR TO THE DYNAMICAL MODELS AND TOOLS OFF THE MODELS. THE
0Z DETERMINISTIC EUROPEAN WAS CONSIDERABLY DIFFERENT FROM THE TELECONNECTIONS
RUN ON THE POSITIVE HEIGHT CENTER, AS THAT MODEL HAS THE POSITIVE HEIGHT CENTER
FURTHER SOUTH AND WEST, RESULTING IN A SHIFT IN THE DOWNSTREAM TROUGH AXIS
LOCATION.

ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER MOST OF THE CONUS UNDER MOSTLY
ABOVE-NORMAL 500-HPA HEIGHT ANOMALIES AND A PROGRESSIVE PATTERN. NEAR-NORMAL
TEMPERATURES ARE FAVORED OVER THE INTERIOR PACIFIC NORTHWEST DUE TO THE
INFLUENCE OF THE TROUGH OFF THE WEST COAST. ABOVE-NORMAL TEMPERATURES ARE
FAVORED OVER WESTERN ALASKA DUE TO ANOMALOUS SOUTHERLY FLOW ALOFT AND SOUTHWEST
LOWER LEVEL FLOW, WHILE THE ALASKA PANHANDLE IS LIKELY INFLUENCED BY HIGH
PRESSURE FROM OVER CANADA.

SOUTHWEST FLOW OVER WESTERN ALASKA FAVORS ABOVE-MEDIAN PRECIPITATION THERE,
WHILE UPPER-LEVEL RIDGING OVER ALASKA FAVORS BELOW-MEDIAN PRECIPITATION FOR
SOUTHERN AND SOUTHEASTERN ALASKA. TROUGHING NEAR THE PACIFIC NORTHWEST AND A
PROGRESSIVE PATTERN FAVOR ABOVE-MEDIAN PRECIPITATION FROM THE PACIFIC NORTHWEST
TO THE GREAT LAKES.  BELOW-MEDIAN PRECIPITATION IS LIKELY ACROSS THE SOUTHWEST
DUE TO THE INFLUENCE OF LOW-LEVEL HIGH PRESSURE, AND FROM THE GULF COAST TO NEW
ENGLAND DUE TO A NORTHWARD DISPLACEMENT OF THE MEAN STORM TRACK.

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, 35% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 20% OF TODAY`S OPERATIONAL 0Z ECMWF
CENTERED ON DAY 8


MODEL OF THE DAY: TODAY`S 0Z EUROPEAN ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD
AGREEMENT AMONG VARIOUS DYNAMICAL AND STATISTICAL TOOLS. SATELLITE DATA INGEST
INTO GFS AND CANADIAN DID NOT HAPPEN PROPERLY, POTENTIALLY IMPACTING TRACK OF
TROPICAL STORM ANA, LOWERING CONFIDENCE BY 1 POINT.

8-14 DAY OUTLOOK FOR OCT 29 - NOV 04, 2014

MODEL SOLUTIONS FOR THE 8-14 DAY PERIOD EXHIBIT MORE DISAGREEMENT THAN DURING
THE 6-10 DAY PERIOD. MOST MODEL SOLUTIONS DEPICT BELOW-NORMAL HEIGHTS OVER THE
EASTERN PACIFIC OFF THE PACIFIC NORTHWEST COAST, AND ABOVE-NORMAL HEIGHTS OVER
THE EASTERN HALF OF THE CONUS. THE 12Z GFS SOLUTION IS MUCH MORE PROGRESSIVE
AND BRINGS BELOW-NORMAL HEIGHTS TO THE GREAT PLAINS. ANOMALIES IN THE CANADIAN
ENSEMBLE MEAN ARE EXTREMELY WEAK.

TELECONNECTIONS BASED ON A POSITIVE HEIGHT CENTER NEAR THE ALEUTIANS, A FEATURE
COMMON TO MANY OF THE MODEL SOLUTIONS, ARE VERY SENSITIVE TO PLACEMENT OF
CENTER OF CIRCULATION. SHIFTING THE CENTER EAST BY ABOUT 10 DEGREES LONGITUDE
COMPLETELY FLIPS THE SIGN OF THE PRECIPITATION ANOMALY FOR THE CALIFORNIA
COAST. THE MODEL SOLUTIONS VARY ABOUT THE PLACEMENT OF THE ABOVE-NORMAL HEIGHTS
NEAR THE ALEUTIANS, SO THIS HIGH LEVEL OF SENSITIVITY INCREASES UNCERTAINTY IN
THE OUTLOOK.

THE LARGELY ABOVE-NORMAL HEIGHTS FOR MOST OF THE CONUS FAVOR ABOVE-NORMAL
TEMPERATURES, EXCEPT FOR THE NORTHERN ROCKIES, NORTHERN GREAT PLAINS, AND GREAT
LAKES WHERE THE STORM TRACK IS LIKELY TO BE LOCATED. SOUTHWEST FLOW AND
ABOVE-NORMAL HEIGHTS FAVOR ABOVE-NORMAL TEMPERATURES OVER ALASKA, EXCEPT FOR
THE PANHANDLE.

SOUTHWEST FLOW FAVORS ABOVE-MEDIAN PRECIPITATION FOR MUCH OF ALASKA, WHILE
LOW-LEVEL RIDGING SUPPORTS BELOW-MEDIAN PRECIPITATION ACROSS THE ALASKA
PANHANDLE. THE ACTIVE STORM TRACK IS LIKELY TO INFLUENCE THE NORTHERN ROCKIES
AND NORTHERN GREAT PLAINS, FAVORING ABOVE-MEDIAN PRECIPITATION FOR THOSE
REGIONS. LOW-LEVEL RIDGING IS FORECAST OVER THE SOUTHEAST, FAVORING
BELOW-MEDIAN PRECIPITATION FOR THE GULF COAST BUT SUPPORTING ABOVE-MEDIAN RAINS
FOR MUCH OF FLORIDA.  GOOD RETURN FLOW OVER THE CENTRAL GREAT PLAINS INCREASES
THE ODDS FOR ABOVE-MEDIANS PRECIPITATION IN THAT REGION.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 30% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, AND 40% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11


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, AND UNCERTAINTY DUE TO MODEL DATA INGEST IRREGULARITIES AND
SENSITIVITY IN TELECONNECTION PATTERNS.



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:
19841007 - 19541019 - 19531011 - 19831101 - 20081002


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 - 19841007 - 19631011 - 19831031 - 19641012


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 27 - 31 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    A     OREGON      N    A     NRN CALIF   A    A
SRN CALIF   A    N     IDAHO       N    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    N     S DAKOTA    A    N
NEBRASKA    A    N     KANSAS      A    A     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    B     W TEXAS     A    B
MINNESOTA   A    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    B     LOUISIANA   A    B     WISCONSIN   A    A
ILLINOIS    A    N     MISSISSIPPI A    B     MICHIGAN    A    A
INDIANA     A    N     OHIO        A    B     KENTUCKY    A    B
TENNESSEE   A    B     ALABAMA     A    B     NEW YORK    A    B
VERMONT     A    B     NEW HAMP    A    B     MAINE       A    B
MASS        A    B     CONN        A    B     RHODE IS    A    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    A    A     AK N SLOPE  A    A
AK ALEUTIAN A    N     AK WESTERN  A    A     AK INT BSN  A    A
AK S INT    N    B     AK SO COAST N    B     AK PNHDL    B    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 29 - NOV 04, 2014

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