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FXUS06 KWBC 161924
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE SEPTEMBER 16 2014

6-10 DAY OUTLOOK FOR SEP 22 - 26 2014

THERE IS FAIR AGREEMENT AMONG TODAY`S ENSEMBLE MEAN FORECASTS OF 6-10 DAY
500-HPA HEIGHTS OVER NORTH AMERICA AND VICINITY. MODELS AGREE ON THE PREDICTION
OF A DEEP TROUGH OVER THE EASTERN NORTH PACIFIC, SOUTH OF SOUTHWESTERN ALASKA.
A STRONG RIDGE IS PREDICTED OVER WESTERN NORTH AMERICA. DOWNSTREAM FROM THESE
FEATURES, MODELS PREDICT A TROUGH OVER THE EASTERN CONUS. THERE IS CONSIDERABLE
SPREAD AMONG THE INDIVIDUAL ENSEMBLE MEMBERS ON THE STRENGTH AND POSITION OF
THE TROUGH OVER THE EASTERN CONUS. CONFIDENCE IS HIGHER IN THE FORECAST FOR THE
WEST AS ALMOST ALL ENSEMBLE MEMBERS PREDICT ABOVE NORMAL HEIGHTS CONSISTENT
WITH THE FORECAST RIDGE.

THE STRONG RIDGE FORECAST OVER THE WESTERN CONUS FAVORS ABOVE-NORMAL
TEMPERATURES WITH A CONSIDERABLE DEGREE OF CONFIDENCE. BELOW-NORMAL
TEMPERATURES ARE FAVORED FROM THE NORTHEASTERN CONUS SOUTHWESTWARD TO THE
SOUTHERN HIGH PLAINS DUE A TROUGH PREDICTED OVER THE EASTERN CONUS. THE ODDS OF
ABOVE-NORMAL TEMPERATURES ARE ELEVATED FOR MUCH OF FLORIDA AHEAD OF A FRONTAL
BOUNDARY EARLY IN THE PERIOD AND CONSISTENT WITH ABOVE NORMAL SEA SURFACE
TEMPERATURES IN THE REGION. ABOVE-NORMAL TEMPERATURES ARE ALSO FAVORED FOR THE
ALASKA PANHANDLE AHEAD OF A PREDICTED TROUGH. BELOW-NORMAL TEMPERATURE
PROBABILITIES ARE ENHANCED FOR PARTS OF NORTHERN ALASKA NEAR THE TROUGH AXIS.
PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE ELEVATED FOR THE ALEUTIANS
CONSISTENT WITH BIAS CORRECTED TEMPERATURES FROM THE ECMWF ENSEMBLES AND GEFS
REFORECAST GUIDANCE AND CONSISTENT WITH ABOVE NORMAL SEA SURFACE TEMPERATURES
IN ADJACENT WATERS.

THE TROUGH OVER THE EASTERN CONUS ENHANCES PROBABILITIES FOR ABOVE-MEDIAN
PRECIPITATION AMOUNTS OVER MUCH OF THE SOUTHEASTERN CONUS AND PARTS OF THE
EASTERN SEABOARD. MEAN SEA LEVEL PRESSURE PREDICTIONS FROM THE MODELS SUGGEST
EASTERLY FLOW OVER THE SOUTHEAST AND GULF COAST STATES, WHICH COMBINED WITH
WARM SSTS IN THE GULF OF MEXICO ELEVATE THE CHANCES FOR ABOVE-MEDIAN
PRECIPITATION FOR THESE REGIONS. SUBSIDENCE BEHIND THE PREDICTED EASTERN CONUS
TROUGH FAVORS BELOW-MEDIAN PRECIPITATION FOR THE NORTHERN PLAINS AND UPPER
MIDWEST. THE PREDICTED WESTERN RIDGE ENHANCES CHANCES FOR BELOW-MEDIAN
PRECIPITATION FOR MUCH OF THE NORTHERN ROCKIES AND NORTHERN INTERMOUNTAIN WEST.
ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE SOUTHERN ROCKIES,
SOUTHWEST, AND SOUTHERN HIGH PLAINS CONSISTENT WITH GEFS REFORECAST GUIDANCE.
THERE ARE ELEVATED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION FOR PARTS OF
SOUTHEASTERN AND NORTHEASTERN ALASKA AHEAD OF A PREDICTED TROUGH. BELOW-MEDIAN
PRECIPITATION IS FAVORED FOR MUCH OF SOUTHWESTERN ALASKA BEHIND THE PREDICTED
TROUGH AXIS.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 10% OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8, 15% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY
8, 10% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 5% OF
TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 15% OF TODAY`S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 5% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 7


MODEL OF THE DAY: NO PREFERENCE

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO A
STRONG FORECAST ANOMALY PATTERN OVER WESTERN NORTH AMERICA OFFSET BY HIGH MODEL
SPREAD OVER THE EASTERN CONUS.

8-14 DAY OUTLOOK FOR SEP 24 - 30 2014

DURING THE WEEK TWO PERIOD, TODAY`S MODEL ENSEMBLES EXHIBIT HIGH SPREAD OVER
MUCH OF THE FORECAST DOMAIN INDICATING HIGH UNCERTAINTY AMONG THE MODEL
SOLUTIONS. TODAY`S ENSEMBLE MEAN SOLUTIONS FORECAST A TROUGH OVER ALASKA.
RELATIVELY LOW-AMPLITUDE FLOW IS FORECAST BY THE ENSEMBLE MEANS OVER MUCH OF
THE CONUS AND A WEAK TROUGH IS INDICATED OVER PARTS OF THE EASTERN CONUS.
HEIGHT ANOMALIES ARE RELATIVELY WEAK OVER THE CONUS IN TODAY`S ECMWF AND
CANADIAN ENSEMBLE MEAN SOLUTIONS DUE, IN PART, TO LARGE SPREAD IN THE COMPONENT
ENSEMBLE MEMBERS BEING AVERAGED TOGETHER. MOREOVER, SUCCESSIVE RUNS OF THE
DETERMINISTIC GFS ARE HAVING DIFFICULTY RESOLVING INDIVIDUAL SHORTWAVE FEATURES
EMBEDDED WITHIN THE OVERALL FLOW ADDING TO THE UNCERTAINTY IN TODAY`S OUTLOOK.
DUE TO THE UNCERTAINTIES EXHIBITED IN THE DETERMINISTIC GFS SOLUTIONS, TODAY`S
WEEK TWO MANUAL HEIGHT BLEND CONSISTS PRIMARILY OF THE ENSEMBLE MEAN SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN CONUS AND NORTHERN PLAINS
UNDERNEATH PREDICTED POSITIVE 500-HPA HEIGHT ANOMALIES. NEAR- TO BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR THE NORTHEASTERN CONUS TO THE SOUTHERN PLAINS DUE
TO THE PREDICTED TROUGH OVER THE EASTERN CONUS AND CONTINUITY WITH THE 6 TO 10
DAY OUTLOOK. ELSEWHERE, TEMPERATURE ANOMALIES FOR THE 8-14 DAY PERIOD ARE
EXPECTED TO BE SIMILAR TO THOSE IN THE 6-10 DAY PERIOD.

THE PRECIPITATION FORECAST FOR THE 8-14 DAY PERIOD FAVORS BELOW-MEDIAN
PRECIPITATION FOR THE GREAT PLAINS, UPPER MIDWEST, MUCH OF THE GREAT LAKES, AND
MUCH OF THE TO THE OHIO VALLEY BEHIND A TROUGH PREDICTED OVER THE EASTERN
CONUS. ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE SOUTHEASTERN
CONUS AHEAD OF THE PREDICTED TROUGH AXIS. NEAR- TO BELOW-MEDIAN PRECIPITATION
PROBABILITIES ARE ENHANCED FOR THE WESTERN CONUS (WITH THE EXCEPTION OF PARTS
OF THE PACIFIC NORTHWEST) UNDERNEATH PREDICTED RIDGING. MOIST FLOW AHEAD OF A
TROUGH OVER THE EASTERN NORTH PACIFIC FAVORS ABOVE-MEDIAN PRECIPITATION FOR THE
ALASKA PANHANDLE AND PARTS OF WASHINGTON STATE. BELOW-MEDIAN PRECIPITATION
PROBABILITIES ARE ENHANCED FOR MUCH OF SOUTHWESTERN ALASKA BEHIND A PREDICTED
TROUGH AXIS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15% 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, 15% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 10, AND 5% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO HIGH SPREAD AMONG TODAY`S ENSEMBLE MEMBERS

FORECASTER: SCOTT HANDEL

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:
19550910 - 20080915 - 19740912 - 19730916 - 19950911


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:
19550909 - 20080914 - 19840929 - 19740910 - 19950912


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 22 - 26 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 24 - 30 2014

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