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FXUS06 KWBC 271902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED MAY 27 2015

6-10 DAY OUTLOOK FOR JUN 02 - 06 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, THE RIDGE CENTER IS FORECAST 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, A TROUGH IS
PREDICTED OVER THE NORTHWESTERN CONUS. ABOVE NORMAL HEIGHTS ARE FORECAST
DOWNSTREAM OF THIS TROUGH FROM THE NORTHERN PLAINS TO THE NORTHEASTERN CONUS.
NEAR TO BELOW NORMAL HEIGHTS ARE PREDICTED NEAR THE GULF COAST CORRESPONDING TO
A TROUGH FORECAST NEAR THE LOWER MISSISSIPPI VALLEY. TODAY`S 500-HPA BLEND
CHART IS WEIGHTED MOST HEAVILY TOWARD 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.

THERE ARE ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR MOST OF THE
NORTH-CENTRAL AND NORTHEASTERN CONUS UNDERNEATH PREDICTED ABOVE NORMAL 500-HPA
HEIGHTS. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED FOR MUCH OF THE
SOUTHEASTERN CONUS AHEAD OF A TROUGH PREDICTED NEAR THE LOWER MISSISSIPPI
VALLEY. BELOW NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE SOUTHERN PLAINS
IN ASSOCIATION WITH THE TROUGH PREDICTED NEAR THE LOWER MISSISSIPPI VALLEY AND
ALSO DUE TO SOIL MOISTURE CONSIDERATIONS. ENHANCED PROBABILITIES OF ABOVE
NORMAL TEMPERATURES ARE INDICATED FOR MUCH OF THE WESTERN CONUS CONSISTENT WITH
BIAS CORRECTED TEMPERATURES FROM THE ECMWF ENSEMBLES AND GEFS REFORECAST
GUIDANCE. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF SOUTHERN AND
WESTERN ALASKA DUE TO PREDICTED RIDGING. NEAR TO BELOW NORMAL TEMPERATURES ARE
FAVORED FOR NORTHEASTERN ALASKA IN ASSOCIATION WITH A TROUGH PREDICTED OVER
NORTHWESTERN CANADA.

PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION ARE ENHANCED FOR MUCH OF THE
SOUTHEASTERN CONUS AHEAD OF A MEAN TROUGH PREDICTED NEAR THE LOWER MISSISSIPPI
VALLEY. BELOW MEDIAN PRECIPITATION IS FAVORED BEHIND THE TROUGH AXIS FOR PARTS
OF THE SOUTHERN PLAINS. BELOW MEDIAN PRECIPITATION IS ALSO FAVORED FOR NEW
ENGLAND UNDERNEATH PREDICTED ABOVE NORMAL HEIGHTS. THERE ARE ENHANCED
PROBABILITIES OF ABOVE MEDIAN PRECIPITATION FOR THE NORTHERN INTERMOUNTAIN
WEST, NORTHERN ROCKIES, AND MUCH OF THE NORTH-CENTRAL CONUS AHEAD OF A TROUGH
PREDICTED OVER THE PACIFIC NORTHWEST. PRECIPITATION ESTIMATES FROM THE GFS AND
ECMWF ENSEMBLES ALSO FAVOR ABOVE MEDIAN PRECIPITATION FOR PARTS OF NEW MEXICO
EXTENDING NORTHEASTWARD TO THE CENTRAL HIGH PLAINS. BELOW MEDIAN PRECIPITATION
IS FAVORED FARTHER TO THE WEST FOR PARTS 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 15% 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, 5% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 10% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 20%
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 5% 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 04 - 10 2015

DURING THE WEEK TWO PERIOD, TODAY`S ENSEMBLE MEAN SOLUTIONS PREDICT MOSTLY
ZONAL FLOW AND ABOVE NORMAL 500-HPA HEIGHTS ACROSS MUCH OF THE NORTHERN HALF OF
THE CONUS. NEAR NORMAL HEIGHTS ARE PREDICTED OVER MUCH OF THE SOUTHERN TIER OF
THE CONUS BY THE ECMWF AND CANADIAN ENSEMBLE MEANS. HOWEVER, BELOW NORMAL
HEIGHTS ARE PREDICTED BY THE GFS ENSEMBLE MEANS OVER THE GULF COAST REGION
CORRESPONDING TO A PREDICTED TROUGH. RIDGING AND NEAR TO ABOVE NORMAL HEIGHTS
ARE FORECAST FOR MUCH OF ALASKA. 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
500-HPA HEIGHTS PREDICTED BY THE ENSEMBLE MEANS. HOWEVER, THERE ARE ENHANCED
PROBABILITIES OF BELOW NORMAL TEMPERATURES FOR MUCH 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,
NEAR TO BELOW NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF NORTHEASTERN ALASKA
CONSISTENT WITH GEFS REFORECAST GUIDANCE.

ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE CENTRAL CONUS CONSISTENT
WITH PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF ENSEMBLES. THERE ARE
ENHANCED PROBABILITIES OF ABOVE MEDIAN PRECIPITATION FOR THE SOUTHEASTERN CONUS
DUE TO A POTENTIAL TROUGH OVER THE LOWER MISSISSIPPI VALLEY. NEAR NORMAL
PRECIPITATION IS FAVORED FARTHER TO THE NORTH OVER THE OHIO VALLEY AND
MID-ATLANTIC REGION DUE TO CONFLICTING GUIDANCE FROM THE ECMWF AND GFS
ENSEMBLES. BELOW MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE NORTHWESTERN
CONUS UNDERNEATH PREDICTED POSITIVE HEIGHT ANOMALIES. BELOW MEDIAN
PRECIPITATION IS FAVORED FOR NORTHERN ALASKA IN ASSOCIATION WITH FORECAST
RIDGING.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 25% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 10% 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 - 19900514 - 19690516 - 19690610


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:
19780602 - 19890603 - 19900506 - 19900513 - 19690517


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 02 - 06 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 04 - 10 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   N    N     WYOMING     A    N
UTAH        A    N     ARIZONA     A    N     COLORADO    N    A
NEW MEXICO  B    A     N DAKOTA    N    N     S DAKOTA    N    A
NEBRASKA    N    A     KANSAS      N    A     OKLAHOMA    N    A
N TEXAS     B    A     S TEXAS     B    A     W TEXAS     B    A
MINNESOTA   N    A     IOWA        A    A     MISSOURI    A    N
ARKANSAS    A    N     LOUISIANA   N    A     WISCONSIN   A    A
ILLINOIS    A    N     MISSISSIPPI A    A     MICHIGAN    A    A
INDIANA     A    N     OHIO        A    N     KENTUCKY    A    N
TENNESSEE   A    N     ALABAMA     A    A     NEW YORK    A    A
VERMONT     A    A     NEW HAMP    A    A     MAINE       A    N
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        A    N     NEW JERSEY  A    N     W VIRGINIA  A    N
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    N
N CAROLINA  A    N     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  N    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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