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FXUS06 KWBC 171948
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU APRIL 17 2014

6-10 DAY OUTLOOK FOR APR 23 - 27 2014

TODAY`S GFS AND ECMWF ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON
THE 500-HPA FLOW PATTERN OVER THE FORECAST DOMAIN. A TROUGH IS FORECAST BY
THESE SOLUTIONS OVER THE ALEUTIANS. DOWNSTREAM OF THIS TROUGH, A RIDGE IS
PREDICTED OVER WESTERN CANADA EXTENDING NORTHWESTWARD TO NORTHEASTERN ALASKA.
FARTHER TO THE SOUTH, A TROUGH IS PREDICTED FOR THE SOUTHWESTERN CONUS WHILE A
FLAT RIDGE IS FORECAST DOWNSTREAM OVER THE SOUTHEASTERN CONUS. TODAY`S 00Z
CANADIAN ENSEMBLE MEAN DIFFERS FROM ITS GFS AND ECWMF COUNTERPARTS IN BRINGING
THE SOUTHWESTERN CONUS TROUGH FARTHER EASTWARD OVER THE CENTRAL AND SOUTHERN
ROCKIES. THE DETERMINISTIC RUNS FROM THE GFS AND ECWMF ARE IN RELATIVELY GOOD
AGREEMENT WITH THEIR RESPECTIVE ENSEMBLE MEAN SOLUTIONS. TODAY`S OFFICIAL
MANUAL 500-HPA HEIGHT BLEND CONTAINS SIGNIFICANT CONTRIBUTIONS FROM BOTH THE
ECWMF- AND GFS-BASED SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE CENTRAL AND EASTERN CONUS
UNDERNEATH FORECAST POSITIVE 500-HPA HEIGHT ANOMALIES. THE TROUGH FORECAST OVER
THE SOUTHWESTERN CONUS ENHANCES PROBABILITIES FOR BELOW-NORMAL TEMPERATURES FOR
PARTS OF THE WESTERN CONUS. ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED
FOR MUCH OF ALASKA AHEAD OF A TROUGH AXIS FORECAST OVER THE ALEUTIANS.

ABOVE-MEDIAN PRECIPITATION PROBABILITIES ARE ENHANCED FOR MUCH OF THE
NORTHWESTERN CONUS DUE TO TROUGHS FORECAST OVER THE SOUTHWESTERN CONUS AND OFF
THE PACIFIC NORTHWEST COAST. ABOVE-MEDIAN PRECIPITATION IS ALSO FAVORED FOR
PARTS OF THE SOUTHERN PLAINS, NORTHEASTWARD TO THE GREAT LAKES AHEAD OF THE
TROUGH PREDICTED OVER THE SOUTHWESTERN CONUS. CONVERSELY, THERE ARE INCREASED
PROBABILITIES FOR BELOW-MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHEASTERN
CONUS IN ASSOCIATION WITH A FORECAST RIDGE. ENHANCED PROBABILITIES OF
ABOVE-MEDIAN PRECIPITATION ARE INDICATED FOR THE ALEUTIANS IN ASSOCIATION WITH
A TROUGH FORECAST IN THE VICINITY. ABOVE-MEDIAN PRECIPITATION IS ALSO FAVORED
FOR PARTS OF THE ALASKA PANHANDLE AHEAD OF A TROUGH PREDICTED JUST OFF THE
COAST. 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...15 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON
DAY 8...15 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...15
PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...10 PERCENT OF
TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8...20 PERCENT OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY`S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 8...AND 5 PERCENT OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 7.

MODEL OF THE DAY: TODAY`S 00Z ECMWF ENSEMBLE MEAN

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

8-14 DAY OUTLOOK FOR APR 25 - MAY 01, 2014

DURING THE WEEK TWO PERIOD, TODAY`S ENSEMBLE MEAN SOLUTIONS FORECAST A FAIRLY
STRONG JET OVER THE NORTH PACIFIC CULMINATING WITH A TROUGH NEAR THE WEST COAST
OF THE CONUS. THE 00Z ECMWF ENSEMBLE MEAN SOLUTION HAS THE TROUGH AXIS JUST OFF
THE COAST WHILE THE 06Z GFS ENSEMBLE MEAN SOLUTION BRINGS A SOUTHERN STREAM
TROUGH INLAND OVER THE SOUTHWESTERN CONUS. DISAGREEMENTS ARE ALSO APPARENT
DOWNSTREAM OF THIS TROUGH AS THE 00Z ECMWF ENSEMBLE MEAN FORECASTS WEAK RIDGING
OVER PARTS OF THE CENTRAL CONUS, WHILE THE 00Z CANADIAN ENSEMBLE MEAN PREDICTS
WEAK CYCLONIC FLOW OVER THIS REGION. WEAK 500-HPA HEIGHT ANOMALIES ARE FORECAST
FOR THE EASTERN CONUS BY ALL OF THE ENSEMBLE MEAN SOLUTIONS DUE, IN PART, TO
DIFFERENCES IN THE COMPONENT ENSEMBLE MEMBERS BEING AVERAGED TOGETHER. THE
DETERMINISTIC GFS SOLUTIONS SHOW A MORE DISTINCT SPLIT FLOW RELATIVE TO THE
ENSEMBLE MEANS CHARACTERIZED BY A SOUTHERN STREAM TROUGH NEAR THE SOUTHWESTERN
CONUS AND NORTHERN STREAM TROUGHS NEAR THE PACIFIC NORTHWEST COAST AND OVER
EASTERN CANADA. HOWEVER, THERE ARE SIGNIFICANT RUN TO RUN DIFFERENCES AMONG THE
DETERMINISTIC GFS ON THE DETAILS OF THESE FEATURES. AGREEMENT IS SOMEWHAT
BETTER OVER ALASKA, WHERE A TROUGH IS PREDICTED OVER THE BERING SEA EXTENDING
SOUTHEASTWARD OVER THE GULF OF ALASKA. TODAY`S WEEK TWO MANUAL 500-HPA HEIGHT
BLEND IS WEIGHTED MOST HEAVILY TOWARD THE ENSEMBLE MEAN SOLUTIONS FROM THE
ECMWF AND GFS.

PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE ENHANCED FOR MUCH OF THE ROCKIES
AND CENTRAL AND SOUTHERN PLAINS AHEAD OF A TROUGH FORECAST NEAR THE WEST COAST.
ABOVE NORMAL TEMPERATURES ARE SLIGHTLY FAVORED FOR PARTS OF THE SOUTHEASTERN
CONUS AND MID-ATLANTIC UNDERNEATH PREDICTED WEAKLY POSITIVE 500-HPA HEIGHT
ANOMALIES AND LOW-AMPLITIDE FLOW. CONVERSELY, BELOW-NORMAL TEMPERATURES ARE
FAVORED FOR PARTS OF THE GREAT LAKES AND NORTHEAST IN ASSOCIATION WITH A TROUGH
PREDICTED OVER EASTERN CANADA. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MUCH
OF ALASKA AHEAD OF THE TROUGH PREDICTED OVER THE ALEUTIANS.

ENHANCED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION ARE INDICATED FOR MUCH OF
THE FAR WEST RELATED TO TROUGHS PREDICTED NEAR THE WEST COAST. ABOVE-MEDIAN
PRECIPITATION IS FAVORED FOR PARTS OF THE PLAINS EXTENDING NORTHEAST TO THE
GREAT LAKES AHEAD OF A TROUGH FORECAST OVER THE SOUTHWESTERN CONUS.
CONVERSELY, THERE ARE INCREASED PROBABILITIES OF BELOW-MEDIAN PRECIPITATION FOR
PARTS OF THE EXTREME SOUTHEASTERN CONUS IN ASSOCIATION WITH WEAK RIDGING.
BELOW-MEDIAN PRECIPITATION IS ALSO FAVORED FOR PARTS OF THE CENTRAL ROCKIES AND
CENTRAL HIGH PLAINS CONSISTENT WITH NAEFS AND GEFS REFORECAST GUIDANCE. THERE
ARE ENHANCED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION FOR THE ALASKA
PANHANDLE RELATED TO A TROUGH FORECAST OFF THE COAST. NEAR TO BELOW-MEDIAN
PRECIPITATION IS FAVORED FOR NORTHWESTERN ALASKA TO THE NORTH OF THE EXPECTED
MEAN STORM TRACK.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10 PERCENT OF TODAY`S
OPERATIONAL 0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 11...15 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON
DAY 11...20 PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...20
PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11...15 PERCENT OF
TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11...AND 10 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 POOR MODEL AGREEMENT.

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 MAY
15

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:
19940405 - 19900416 - 19700331 - 20000410 - 19930420


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:
19940404 - 19700331 - 19900327 - 19900417 - 19730414


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 23 - 27 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 25 - MAY 01, 2014

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