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FXUS06 KWBC 191905
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI SEPTEMBER 19 2014

6-10 DAY OUTLOOK FOR SEP 25 - 29 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 TROUGH OVER ALASKA. DOWNSTREAM, MOST MODELS PREDICT A TROUGH OVER THE
NORTHWESTERN CONUS WHILE RIDGING IS FORECAST OVER MUCH OF THE EASTERN CONUS.
MODEL SPREAD IS LOWER TODAY RELATIVE TO THAT EXPERIENCED EARLIER THIS WEEK
RESULTING IN AN INCREASE IN CONFIDENCE IN TODAY`S OUTLOOK. TODAY`S OFFICIAL
500-HPA HEIGHT BLEND IS BASED PRIMARILY ON THE ENSEMBLE MEAN SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FROM PARTS OF THE SOUTHWESTERN CONUS TO
THE NORTHERN PLAINS AHEAD OF A TROUGH PREDICTED NEAR THE NORTHWESTERN CONUS.
NEAR- TO BELOW-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE NORTHWESTERN
CONUS IN ASSOCIATION WITH THE FORECAST TROUGH. THE ODDS OF ABOVE-NORMAL
TEMPERATURES ARE ELEVATED FOR SOUTHERN FLORIDA AND MUCH OF THE GULF COAST
CONSISTENT WITH ABOVE NORMAL SEA SURFACE TEMPERATURES IN THE REGION AND BIAS
CORRECTED TEMPERATURES FROM THE 0Z ECMWF ENSEMBLES. 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 WITH ABOVE NORMAL SEA SURFACE TEMPERATURES IN ADJACENT
WATERS.

ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR THE PACIFIC NORTHWEST AND THE ROCKIES
DUE TO A TROUGH PREDICTED NEAR THE NORTHWESTERN CONUS. AN ANTICIPATED FRONT AND
MEAN EASTERLY FLOW ENHANCES PROBABILITIES FOR ABOVE-MEDIAN PRECIPITATION
AMOUNTS OVER FLORIDA. PREDICTED SURFACE HIGH PRESSURE FAVORS BELOW-MEDIAN
PRECIPITATION FOR THE NORTHEASTERN CONUS. THERE ARE ELEVATED PROBABILITIES OF
ABOVE-MEDIAN PRECIPITATION FOR PARTS OF THE ALASKA PANHANDLE AHEAD OF A
PREDICTED TROUGH. BELOW-MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE
REMAINDER OF ALASKA NEAR AND WEST OF THE PREDICTED TROUGH AXIS.

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, 5% OF
TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 30% 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, AND
15% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: 0Z ECMWF ENSEMBLE MEAN

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

8-14 DAY OUTLOOK FOR SEP 27 - OCT 03, 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 ECMWF AND CANADIAN ENSEMBLE
MEANS OVER MUCH OF THE CONUS DUE, IN PART, TO LARGE VARIATIONS AMONG THE
COMPONENT ENSEMBLE MEMBERS BEING AVERAGED TOGETHER. TODAY`S GFS-BASED SOLUTIONS
PREDICT A TROUGH OVER THE ROCKIES AND STRONG RIDGING OVER MUCH OF EASTERN NORTH
AMERICA. DUE TO LARGE UNCERTAINTIES AMONG INDIVIDUAL ENSEMBLE MEMBERS, TODAY`S
WEEK TWO MANUAL HEIGHT BLEND CONSISTS PRIMARILY OF THE ENSEMBLE MEAN SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE EASTERN CONUS DUE TO PREDICTED
RIDGING. ENHANCED PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE ALSO INDICATED
FOR PARTS OF CALIFORNIA, UNDERNEATH PREDICTED POSITIVE 500-HPA HEIGHT
ANOMALIES. NEAR-NORMAL TEMPERATURES ARE FAVORED FOR THE PACIFIC NORTHWEST AND
MUCH OF THE INTERMOUNTAIN WEST IN ASSOCIATION WITH A PREDICTED TROUGH.
ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ELEVATED FOR THE ALASKA PANHANDLE
AHEAD OF A PREDICTED TROUGH. PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE
ENHANCED FOR THE ALEUTIANS CONSISTENT WITH BIAS CORRECTED TEMPERATURES FROM THE
ECMWF ENSEMBLES AND WITH ABOVE NORMAL SEA SURFACE TEMPERATURES IN ADJACENT
WATERS.

THE PRECIPITATION FORECAST FOR THE 8-14 DAY PERIOD FAVORS ABOVE-MEDIAN
PRECIPITATION FOR THE PACIFIC NORTHWEST, ROCKIES, AND MUCH OF THE PLAINS IN
ASSOCIATION WITH A TROUGH PREDICTED OVER THE ROCKIES IN THE MANUAL BLEND.
BELOW-MEDIAN PRECIPITATION PROBABILITIES ARE ENHANCED FOR MUCH OF THE NORTHEAST
CONUS DUE TO PREDICTED MEAN SURFACE HIGH PRESSURE. ABOVE-MEDIAN PRECIPITATION
PROBABILITIES ARE ENHANCED FOR MUCH OF THE SOUTHEASTERN CONUS CONSISTENT WITH
NAEFS AND GEFS REFORECAST GUIDANCE. MOIST FLOW AHEAD OF A TROUGH OVER THE
EASTERN NORTH PACIFIC FAVORS ABOVE-MEDIAN PRECIPITATION FOR THE ALASKA
PANHANDLE. BELOW-MEDIAN PRECIPITATION PROBABILITIES ARE ENHANCED FOR MUCH OF
THE REMAINDER OF ALASKA SIMILAR TO THAT PREDICTED IN THE 6 TO 10 DAY PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 30% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 20% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 5% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 5% 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 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
OCTOBER 16

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:
19841002 - 19640914 - 19840914 - 19760902 - 19620919


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:
19640914 - 19841002 - 19620918 - 19840917 - 19800926


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 25 - 29 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 27 - OCT 03, 2014

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