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FXUS06 KWBC 261907
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE MAY 26 2015

6-10 DAY OUTLOOK FOR JUN 01 - 05 2015

TODAY`S MODEL SOLUTIONS ARE IN FAIR AGREEMENT ON THE 500-HPA CIRCULATION
PATTERN OVER NORTH AMERICA AND VICINITY. A TROUGH IS PREDICTED BY THE ENSEMBLE
MEANS OVER THE WESTERN ALEUTIANS AND A RIDGE IS FORECAST DOWNSTREAM OVER MUCH
OF THE REMAINDER OF ALASKA. HOWEVER, SOME SOLUTIONS, SUCH AS THE DETERMINISTIC
0Z GFS AND 0Z ECMWF, PREDICT THE RIDGE CENTER TO PINCH OFF FROM THE MAIN FLOW
AND MOVE TO THE NORTH OF THE STATE, ALLOWING A DOWNSTREAM TROUGH TO AFFECT
NORTHEASTERN ALASKA. FARTHER TO THE SOUTH, THE ENSEMBLE MEANS FORECAST WEAK
TROUGHS OVER THE PACIFIC NORTHWEST AND OVER 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 SOUTHERN AND WESTERN 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 PARTS OF THE SOUTHERN 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 THE EASTERN QUARTER OF THE CONUS AHEAD OF THE PREDICTED MEAN
TROUGH AXIS.

PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION ARE ENHANCED FOR MUCH OF THE
SOUTHEASTERN CONUS AHEAD OF A MEAN TROUGH PREDICTED NEAR THE MISSISSIPPI
VALLEY. BELOW MEDIAN PRECIPITATION IS FAVORED BEHIND THE TROUGH AXIS FOR MUCH
OF THE SOUTHERN HIGH PLAINS. ABOVE MEDIAN PRECIPITATION IS FAVORED FOR THE
NORTHERN INTERMOUNTAIN WEST, NORTHERN ROCKIES, AND PARTS OF THE NORTHERN PLAINS
AHEAD OF A TROUGH PREDICTED OVER THE PACIFIC NORTHWEST. BELOW MEDIAN
PRECIPITATION IS FAVORED FARTHER TO THE SOUTH FOR MUCH OF THE GREAT BASIN
CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF ENSEMBLE
MEMBERS. BELOW MEDIAN PRECIPITATION IS ALSO 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, 10% 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, 15% 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: AVERAGE, 3 OUT OF 5, DUE TO FAIR
MODEL AGREEMENT

8-14 DAY OUTLOOK FOR JUN 03 - 09 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 BY THE ENSEMBLE MEANS ACROSS MUCH OF THE NORTHERN HALF OF THE CONUS
WHILE NEAR NORMAL HEIGHTS ARE PREDICTED OVER MUCH OF THE SOUTHERN TIER OF THE
CONUS. HOWEVER, THE DETERMINISTIC 0Z AND 6Z GFS FORECAST A TROUGH OVER THE
EASTERN 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 WESTERN AND EASTERN CONUS
CONSISTENT WITH FORECAST LOW AMPLITUDE FLOW AND ASSOCIATED NEAR TO ABOVE NORMAL
HEIGHTS PREDICTED BY THE ENSEMBLE MEANS. HOWEVER, THERE ARE ENHANCED
PROBABILITIES OF NEAR TO BELOW NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL
CONUS BEHIND A POTENTIAL TROUGH PREDICTED OVER THE EASTERN CONUS BY THE GFS
SOLUTIONS. THE GREATEST PROBABILITIES FOR BELOW NORMAL TEMPERATURES ARE
INDICATED FOR PARTS OF THE SOUTHERN PLAINS DUE, IN PART, TO SOIL MOISTURE
CONSIDERATIONS. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MOST OF SOUTHWESTERN
ALASKA IN ASSOCIATION WITH PREDICTED RIDGING. HOWEVER, BELOW NORMAL
TEMPERATURES ARE FAVORED FOR PARTS OF NORTHEASTERN ALASKA CONSISTENT WITH GEFS
REFORECAST GUIDANCE.

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 MUCH OF THE WESTERN QUARTER OF THE
CONUS CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF ENSEMBLES.
BELOW MEDIAN PRECIPITATION IS FAVORED FOR NORTHWESTERN ALASKA IN ASSOCIATION
WITH PREDICTED RIDGING. CONVERSELY, THERE ARE ENHANCED PROBABILITIES OF ABOVE
MEDIAN PRECIPITATION FOR THE PANHANDLE AHEAD OF A TROUGH PREDICTED OFF THE
COAST.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 10% 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, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 10, 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 10% 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 FAIRLY HIGH MODEL SPREAD ACROSS MUCH OF THE FORECAST DOMAIN.

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:
19780603 - 19890603 - 19690609 - 19900508 - 19900514


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 - 19780602 - 19710604 - 20030608


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 01 - 05 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     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    N     COLORADO    A    N
NEW MEXICO  A    N     N DAKOTA    A    A     S DAKOTA    A    A
NEBRASKA    A    N     KANSAS      N    N     OKLAHOMA    N    B
N TEXAS     N    N     S TEXAS     B    N     W TEXAS     N    B
MINNESOTA   A    A     IOWA        A    N     MISSOURI    A    N
ARKANSAS    N    A     LOUISIANA   N    A     WISCONSIN   A    N
ILLINOIS    A    N     MISSISSIPPI A    A     MICHIGAN    A    N
INDIANA     A    N     OHIO        A    N     KENTUCKY    A    A
TENNESSEE   A    A     ALABAMA     A    A     NEW YORK    A    N
VERMONT     A    N     NEW HAMP    A    N     MAINE       A    N
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        A    N     NEW JERSEY  A    N     W VIRGINIA  A    A
MARYLAND    A    N     DELAWARE    A    N     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    B     AK INT BSN  N    B
AK S INT    A    B     AK SO COAST A    N     AK PNHDL    A    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 03 - 09 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     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    N
UTAH        A    B     ARIZONA     A    N     COLORADO    N    N
NEW MEXICO  N    A     N DAKOTA    N    A     S DAKOTA    N    A
NEBRASKA    N    A     KANSAS      N    A     OKLAHOMA    N    A
N TEXAS     N    N     S TEXAS     B    N     W TEXAS     B    N
MINNESOTA   N    A     IOWA        N    A     MISSOURI    N    A
ARKANSAS    N    A     LOUISIANA   N    A     WISCONSIN   N    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  B    B
AK ALEUTIAN A    N     AK WESTERN  A    B     AK INT BSN  N    N
AK S INT    A    N     AK SO COAST A    N     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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