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FXUS06 KWBC 151932
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE APRIL 15 2014

6-10 DAY OUTLOOK FOR APR 21 - 25 2014

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIR AGREEMENT ON THE 500-HPA FLOW
PATTERN OVER THE FORECAST DOMAIN. HOWEVER, ENSEMBLE SPREAD IS HIGH AND THERE
ARE SIGNIFICANT DIFFERENCES AMONG THE DETERMINISTIC RUNS. A TROUGH IS FORECAST
BY THE ENSEMBLE MEANS OVER THE ALEUTIANS. DOWNSTREAM OF THIS TROUGH, A RIDGE IS
PREDICTED OVER WESTERN CANADA EXTENDING NORTHWESTWARD TO INTERIOR ALASKA. OVER
THE CONUS, TROUGHS ARE PREDICTED FOR THE SOUTHWEST AND THE NORTHEAST WHILE
POSITIVE 500-HPA HEIGHT ANOMALIES ARE FORECAST OVER MUCH OF THE CENTER OF THE
COUNTRY. THERE ARE SOME SIGNIFICANT DIFFERENCES BETWEEN THE DETERMINISTIC GFS
AND ECMWF SOLUTIONS OVER THE CONUS. TODAY`S DETERMINISTIC GFS RUNS FORECAST AN
AMPLIFIED PATTERN WITH A STRONG TROUGH OVER THE WESTERN CONUS WHILE TODAY`S
DETERMINISTIC 00Z ECMWF PREDICTS ZONAL FLOW FROM COAST TO COAST. DUE TO THE
HIGH UNCERTAINTIES AMONG THE DETERMINISTIC RUNS, MOST OF THE WEIGHT IN THE
OFFICIAL 500-HPA HEIGHT BLEND WAS GIVEN TO THE ENSEMBLE MEAN SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE CENTRAL CONUS UNDERNEATH
FORECAST POSITIVE 500-HPA HEIGHT ANOMALIES. THE TROUGH FORECAST OVER THE
NORTHEASTERN CONUS ENHANCES PROBABILITIES FOR BELOW-NORMAL TEMPERATURES FOR
PARTS OF THE GREAT LAKES AND NORTHEAST. ENHANCED PROBABILITIES OF BELOW-NORMAL
TEMPERATURES ARE ALSO INDICATED FOR PARTS OF FLORIDA BEHIND A TROUGH AXIS OVER
THE ATLANTIC OCEAN. ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ALSO ENHANCED
FOR MUCH OF ALASKA AHEAD OF A TROUGH AXIS FORECAST OVER THE ALEUTIANS.

PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION ARE ENHANCED FOR MUCH OF THE
NORTHWESTERN CONUS AHEAD OF A TROUGH PREDICTED OFF THE PACIFIC NORTHWEST COAST.
ABOVE-MEDIAN PRECIPITATION IS ALSO FAVORED FOR MUCH OF THE SOUTHERN PLAINS
AHEAD OF A TROUGH PREDICTED OVER THE SOUTHWESTERN CONUS. CONVERSELY, THERE ARE
INCREASED PROBABILITIES FOR BELOW-MEDIAN PRECIPITATION FOR PARTS OF THE
SOUTHEASTERN CONUS BEHIND A TROUGH FORECAST OVER THE WESTERN ATLANTIC OCEAN.
MOIST FLOW ASSOCIATED WITH A FORECAST TROUGH OVER THE ALEUTIANS FAVORS
ABOVE-MEDIAN PRECIPITATION FOR MUCH OF SOUTHERN ALASKA. ENHANCED PROBABILITIES
OF BELOW-MEDIAN PRECIPITATION ARE INDICATED FOR PARTS OF NORTHWESTERN ALASKA TO
THE NORTH OF THE EXPECTED MEAN STORM TRACK.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY`S OPERATIONAL 0Z
GFS CENTERED ON DAY 8...5 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY
8...15 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT
OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8...20 PERCENT OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8...10 PERCENT OF TODAY`S 0Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 8...5 PERCENT OF YESTERDAY`S OPERATIONAL 12Z ECMWF
CENTERED ON DAY 7...AND 5 PERCENT OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7.

MODEL OF THE DAY: TODAY`S 00Z ECMWF ENSEMBLE MEAN AND TODAY`S 06Z GFS ENSEMBLE
MEAN (TIED)

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: BELOW AVERAGE, 2 OUT OF 5, DUE TO
RELATIVELY HIGH SPREAD AMONG THE ENSEMBLE MEMBERS.

8-14 DAY OUTLOOK FOR APR 23 - 29 2014

DURING THE WEEK TWO-PERIOD, TODAY`S MODEL SOLUTIONS ARE CHARACTERIZED BY
RELATIVELY HIGH SPREAD AMONG THE ENSEMBLE MEMBERS. THE ECWMF AND CANADIAN
ENSEMBLE MEAN SOLUTIONS FORECAST ZONAL FLOW OVER THE CONUS FROM COAST TO COAST
DUE, IN PART, TO DIFFERENCES IN THE COMPONENT ENSEMBLE MEMBERS BEING AVERAGED
TOGETHER. IN CONTRAST, THE GFS-BASED SOLUTIONS PREDICT A MORE AMPLIFIED PATTERN
WITH A FAIRLY STRONG TROUGH OVER THE SOUTHWESTERN CONUS. AGREEMENT IS BETTER
OVER ALASKA WHERE A TROUGH IS PREDICTED OVER THE ALEUTIANS AND DOWNSTREAM
RIDGING IS FORECAST OVER THE INTERIOR. TODAY`S WEEK TWO MANUAL 500-HPA HEIGHT
BLEND IS WEIGHTED MOST HEAVILY TOWARD THE ECWMF ENSEMBLE MEAN SOLUTIONS DUE, IN
PART, TO CONSIDERATION OF RECENT SKILL AND TO ANALOG CORRELATIONS.

PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE ENHANCED FOR MUCH OF THE CENTRAL
CONUS AND PARTS OF THE NORTHWESTERN CONUS UNDERNEATH PREDICTED POSITIVE 500-HPA
HEIGHT ANOMALIES. BELOW-NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE GREAT
LAKES REGION EXTENDING TO NORTHERN NEW ENGLAND DUE TO A WEAK TROUGH PREDICTED
NEAR THESE REGIONS. BELOW-NORMAL TEMPERATURES ARE ALSO FAVORED FOR PARTS OF THE
WESTERN GULF COAST REGION DUE, IN PART, TO BELOW NORMAL SSTS IN ADJACENT
WATERS. CONVERSELY, ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED FOR
MUCH OF ALASKA AHEAD OF THE TROUGH PREDICTED OVER THE ALEUTIANS.

ENHANCED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION ARE INDICATED ALONG MUCH
OF THE NORTHWESTERN CONUS AHEAD OF A TROUGH FORECAST OFF THE PACIFIC NORTHWEST
COAST. ABOVE-MEDIAN PRECIPITATION IS ALSO FAVORED FOR MUCH OF THE CENTRAL CONUS
AHEAD OF A TROUGH FORECAST OVER THE SOUTHWESTERN CONUS. THERE ARE ENHANCED
PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION FOR SOUTHERN ALASKA IN ASSOCIATION
WITH A TROUGH FORECAST OVER THE ALEUTIANS. CONVERSELY, ENHANCED PROBABILITIES
OF BELOW-MEDIAN PRECIPITATION IS INDICATED FOR PARTS OF NORTHWESTERN ALASKA TO
THE NORTH OF THE EXPECTED MEAN STORM TRACK.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 5 PERCENT OF TODAY`S OPERATIONAL
0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED
ON DAY 11...20 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...15
PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...25 PERCENT OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11...5 PERCENT OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11...AND 20 PERCENT 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 RELATIVELY LARGE SPREAD AMONG 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
APRIL 17

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:
19940404 - 19790403 - 20000410 - 20040421 - 19580429


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:
20090428 - 19790403 - 19940404 - 19700325 - 19660426


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 21 - 25 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       A    A     NEVADA      A    A
W MONTANA   A    A     E MONTANA   A    A     WYOMING     A    A
UTAH        A    A     ARIZONA     A    N     COLORADO    A    N
NEW MEXICO  A    N     N DAKOTA    A    A     S DAKOTA    A    A
NEBRASKA    A    N     KANSAS      A    A     OKLAHOMA    A    A
N TEXAS     A    A     S TEXAS     N    A     W TEXAS     A    A
MINNESOTA   A    A     IOWA        A    N     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   N    N     WISCONSIN   A    N
ILLINOIS    A    N     MISSISSIPPI N    N     MICHIGAN    N    N
INDIANA     A    N     OHIO        N    N     KENTUCKY    A    N
TENNESSEE   A    N     ALABAMA     N    B     NEW YORK    B    N
VERMONT     B    N     NEW HAMP    B    N     MAINE       B    N
MASS        N    N     CONN        N    N     RHODE IS    N    N
PENN        N    N     NEW JERSEY  N    N     W VIRGINIA  N    N
MARYLAND    N    N     DELAWARE    N    N     VIRGINIA    N    N
N CAROLINA  N    N     S CAROLINA  N    B     GEORGIA     N    B
FL PNHDL    N    B     FL PENIN    B    B     AK N SLOPE  A    N
AK ALEUTIAN N    A     AK WESTERN  A    N     AK INT BSN  A    N
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    N    A



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 23 - 29 2014

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