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FXUS06 KWBC 241902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI APRIL 24 2015

6-10 DAY OUTLOOK FOR APR 30 - MAY 04, 2015

TODAY`S ENSEMBLE MODEL SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA
FLOW PATTERN EXPECTED OVER MUCH OF NORTH AMERICA AND VICINITY. ALL MODELS ARE
FORECASTING A TROUGH OVER THE GULF OF ALASKA OFF THE WEST COAST OF NORTH
AMERICA AND A RIDGE OVER THE CENTRAL CONUS. FARTHER TO THE EAST, A TROUGH IS
PREDICTED BY ALL OF TODAY`S MODEL SOLUTIONS NEAR THE EAST COAST OF NORTH
AMERICA WITH NEGATIVE 500-HPA HEIGHT ANOMALIES FORECAST OVER THE EASTERN CONUS.
THE ENSEMBLE SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE FORECAST
DOMAIN.

BELOW NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE EASTERN OF CONUS AND THE
COASTAL PLAINS IN ASSOCIATION WITH BELOW NORMAL 500-HPA HEIGHTS. RIDGING OVER
CENTRAL NORTH AMERICA INCREASES THE CHANCES FOR ABOVE NORMAL TEMPERATURES FOR
THE WESTERN AND CENTRAL CONUS INCLUDE ALASKA, THE ALEUTIANS AND THE ALASKA
PANHANDLE.

BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE CENTRAL AND EASTERN CONUS DUE TO
DESCENT EXPECTED ON THE WESTERN SIDE OF THE TROUGH FORECAST OVER THE EASTERN
U.S. AND THE WEST-CENTRAL CONUS IN ASSOCIATION WITH THE RIDGE OVER CENTRAL AND
WESTERN NORTH AMERICA.  ABOVE MEDIAN PRECIPITATION IS FAVORED FOR NEW MEXICO,
CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF CALIBRATED
REFORECAST TOOLS. THERE ARE ENHANCED CHANCES OF BELOW MEDIAN PRECIPITATION FOR
ALASKA WEST OF A TROUGH PREDICTED OVER THE GULF OF ALASKA. THE TROUGH OVER THE
GULF OF ALASKA ENHANCES PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR THE
ALASKA PANHANDLE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 20%
OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, AND 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
8


MODEL OF THE DAY: NO PREFERENCE

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
FAIRLY GOOD ENSEMBLE MEAN AGREEMENT.

8-14 DAY OUTLOOK FOR MAY 02 - 08 2015

TODAY`S WEEK TWO ENSEMBLE MEAN SOLUTIONS DEPICT A MEAN 500-HPA TROUGH OVER THE
GULF OF ALASKA MOVING EASTWARD COMPARED TO YESTERDAY`S PATTERN. A TROUGH IS
FORECAST OVER THE WEST COAST WITH A RIDGE OVER WESTERN CANADA AND MUCH OF THE
CENTRAL CONUS.

ABOVE NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED FOR ALASKA, THE ALEUTIANS,
THE ALASKA PANHANDLE, AND MUCH OF THE CONUS IN ASSOCIATION WITH POSITIVE
500-HPA HEIGHT ANOMALIES AND THE RIDGE FORECAST OVER THE CENTRAL CONUS. WITH
THE YESTERDAY`S TROUGH OVER THE EASTERN CONUS MOVING OVER THE ATLANTIC AND THE
MEAN RIDGE MOVING EASTWARD, ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE GULF
COAST, ALSO INFLUENCED BY THE POSITIVE SEA SURFACE TEMPERATURE ANOMALIES.

PROBABILITIES OF BELOW MEDIAN PRECIPITATION ARE ENHANCED WEST OF THE PREDICTED
TROUGH FOR THE PARTS OF OHIO AND TENNESSEE VALLEYS, AND THE MID-ATLANTIC COAST.
ENHANCED PROBABILITIES OF ABOVE MEDIAN PRECIPITATION ARE INDICATED FOR THE
GREAT PLAINS, THE ROCKIES AND THE GREAT BASIN IN ASSOCIATION WITH A MEAN TROUGH
PREDICTED OVER THE WEST COAST. ABOVE MEDIAN PRECIPITATION IS ALSO FAVORED FOR
THE GULF COAST, CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF
CALIBRATED REFORECAST TOOLS. THERE ARE ENHANCED PROBABILITIES OF BELOW MEDIAN
PRECIPITATION FOR EASTERN ALASKA AND THE ALASKA PANHANDLE DUE TO THE
EXPECTATION OF ABOVE NORMAL 500-HPA HEIGHTS.


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


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO
RELATIVELY GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS OFFSET BY LARGE
SPREAD AMONG THE COMPONENT ENSEMBLE MEMBERS OVER MUCH OF NORTH AMERICA

FORECASTER: QIN GINGER ZHANG

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
21

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:
19880419 - 20080508 - 19800508 - 20090408 - 19730428


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:
19880419 - 20080507 - 19790407 - 20090408 - 19730427


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 30 - MAY 04, 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 02 - 08 2015

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