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FXUS06 KWBC 251902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON MAY 25 2015

6-10 DAY OUTLOOK FOR MAY 31 - JUN 04, 2015

TODAY`S MODEL SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA CIRCULATION
PATTERN OVER NORTH AMERICA AND VICINITY. A TROUGH IS PREDICTED OVER THE WESTERN
ALEUTIANS AND A RIDGE IS FORECAST DOWNSTREAM OVER MUCH OF THE REMAINDER OF
ALASKA. FARTHER TO THE SOUTH, A BROAD, LOW AMPLITUDE TROUGH IS PREDICTED OVER
THE PACIFIC AND A WEAK TROUGH IS FORECAST NEAR THE MISSISSIPPI VALLEY.
RELATIVELY LOW AMPLITUDE FLOW IS PREDICTED BY MOST MODEL SOLUTIONS ACROSS THE
CONUS. AS A RESULT, NEAR TO ABOVE NORMAL HEIGHTS ARE FORECAST OVER MUCH OF THE
COUNTRY. TODAY`S 500-HPA BLEND CHART IS WEIGHTED MOST HEAVILY ON THE ECMWF AND
CANADIAN ENSEMBLE MEANS AND BASED PRIMARILY ON CONSIDERATIONS OF RECENT SKILL
AND ON ANALOG CORRELATIONS, WHICH MEASURE HOW CLOSELY THE FORECAST PATTERN
MATCHES CASES THAT HAVE OCCURRED IN THE PAST.

ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF ALASKA DUE TO PREDICTED
RIDGING. ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES ARE ALSO INDICATED
FOR MUCH OF THE WESTERN CONUS CONSISTENT WITH BIAS CORRECTED TEMPERATURES FROM
THE ECMWF ENSEMBLES AND GEFS REFORECAST GUIDANCE. BELOW NORMAL TEMPERATURES ARE
FAVORED FOR MUCH OF THE SOUTHERN PLAINS AND PARTS OF THE CENTRAL PLAINS IN
ASSOCIATION WITH A TROUGH PREDICTED NEAR THE MISSISSIPPI VALLEY AND ALSO DUE TO
SOIL MOISTURE CONSIDERATIONS. THERE ARE ENHANCED PROBABILITIES OF ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE EASTERN QUARTER OF THE CONUS AHEAD OF THE
PREDICTED MEAN TROUGH AXIS.

PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION ARE ENHANCED FOR MUCH OF THE
EASTERN CONUS AND SOUTHERN PLAINS IN ASSOCIATION WITH A MEAN TROUGH PREDICTED
NEAR THE MISSISSIPPI VALLEY. NEAR TO BELOW MEDIAN PRECIPITATION IS FAVORED
BEHIND THE TROUGH AXIS FOR MUCH OF THE CENTRAL PLAINS AND CENTRAL AND SOUTHERN
ROCKIES. ABOVE MEDIAN PRECIPITATION IS FAVORED FOR THE NORTHERN INTERMOUNTAIN
WEST, NORTHERN ROCKIES, AND PARTS OF THE NORTHERN PLAINS CONSISTENT WITH
PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF ENSEMBLE MEMBERS. CONVERSELY,
BELOW MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF ALASKA DUE TO PREDICTED
RIDGING.


TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 25% 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, 20% OF
TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 10% OF YESTERDAY`S 12Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 7


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE VARIOUS MODELS AND SURFACE TOOLS.

8-14 DAY OUTLOOK FOR JUN 02 - 08 2015

DURING THE WEEK TWO PERIOD, TODAY`S ENSEMBLE MEAN SOLUTIONS ARE SIMILAR TO THAT
PREDICTED DURING THE 6 TO 10 DAY PERIOD. RIDGING AND ABOVE NORMAL HEIGHTS ARE
FORECAST FOR MUCH OF ALASKA. MOSTLY ZONAL FLOW AND ABOVE NORMAL HEIGHTS ARE
FORECAST ACROSS MUCH OF THE NORTHERN HALF OF THE CONUS WHILE NEAR NORMAL
HEIGHTS ARE PREDICTED OVER MUCH OF THE SOUTHERN TIER OF THE CONUS. ENSEMBLE
SPREAD IS MODERATELY HIGH OVER MUCH OF THE FORECAST DOMAIN INDICATING MODEL
DIFFERENCES IN RESOLVING INDIVIDUAL SHORTWAVE FEATURES WITHIN THE OVERALL FLOW
PATTERN. TODAY`S WEEK TWO MANUAL 500-HPA HEIGHT BLEND IS BASED PRIMARILY ON THE
ENSEMBLE MEAN SOLUTIONS WITH THE GREATEST WEIGHTS GIVEN TO TODAY`S 0Z ECMWF AND
0Z CANADIAN ENSEMBLE MEANS.

ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE CONUS IN ASSOCIATION WITH
FORECAST LOW AMPLITUDE FLOW AND PREDICTED NEAR TO ABOVE NORMAL HEIGHTS.
HOWEVER, THERE ARE ENHANCED PROBABILITIES OF BELOW NORMAL TEMPERATURES FOR
PARTS OF THE SOUTHERN PLAINS DUE, IN PART, TO SOIL MOISTURE CONSIDERATIONS.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MOST OF ALASKA IN ASSOCIATION WITH
PREDICTED RIDGING.

ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE EASTERN CONUS CONSISTENT
WITH GEFS REFORECAST GUIDANCE. HOWEVER ENHANCED PROBABILITIES OF ABOVE MEDIAN
PRECIPITATION ARE WEAK ACROSS MUCH OF THE REGION DUE TO CONFLICTING GUIDANCE
FROM THE ECMWF ENSEMBLES, WHICH PREDICT A RELATIVELY DRIER PATTERN. NEAR TO
BELOW MEDIAN PRECIPITATION IS FAVORED FOR MOST OF ALASKA IN ASSOCIATION WITH
PREDICTED RIDGING. NEAR TO BELOW MEDIAN PRECIPITATION IS ALSO FAVORED FOR MUCH
OF THE WESTERN QUARTER OF THE CONUS CONSISTENT WITH GEFS REFORECAST GUIDANCE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 5% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11,
10% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 25% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 25% 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: AVERAGE, 3 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS OFFSET BY DISAGREEMENTS
AMONG THE SURFACE TOOLS (PARTICULARLY FOR PRECIPITATION).

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
JUNE 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:
19710605 - 19690608 - 19900507 - 19890603 - 20080526


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:
19900506 - 19890602 - 19710604 - 20030607 - 20080526


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 31 - JUN 04, 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 02 - 08 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    N     NEVADA      A    B
W MONTANA   A    N     E MONTANA   A    A     WYOMING     A    N
UTAH        A    N     ARIZONA     A    N     COLORADO    A    N
NEW MEXICO  N    A     N DAKOTA    A    A     S DAKOTA    A    A
NEBRASKA    A    N     KANSAS      A    N     OKLAHOMA    N    N
N TEXAS     B    N     S TEXAS     B    N     W TEXAS     B    N
MINNESOTA   A    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   A    A
ILLINOIS    A    A     MISSISSIPPI A    A     MICHIGAN    A    A
INDIANA     A    A     OHIO        A    A     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    A     NEW YORK    A    A
VERMONT     A    A     NEW HAMP    A    A     MAINE       A    A
MASS        A    A     CONN        A    A     RHODE IS    A    A
PENN        A    A     NEW JERSEY  A    A     W VIRGINIA  A    A
MARYLAND    A    A     DELAWARE    A    A     VIRGINIA    A    A
N CAROLINA  A    A     S CAROLINA  A    A     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  N    B
AK ALEUTIAN A    N     AK WESTERN  A    N     AK INT BSN  A    B
AK S INT    A    N     AK SO COAST A    N     AK PNHDL    A    N

                           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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