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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 THU MAY 25 2017

6-10 DAY OUTLOOK FOR MAY 31 - JUN 04, 2017

RECENT ENSEMBLE MEAN SOLUTIONS OF THE GEFS, ECMWF, AND CANADIAN MODELS ARE IN
GOOD AGREEMENT ON THE LARGE SCALE CIRCULATION PATTERN FORECAST FOR THE 6-10 DAY
PERIOD. TROUGHS ARE ANTICIPATED OVER THE EASTERN CONUS, CALIFORNIA, AND THE
BERING SEA/ALEUTIANS/ALASKA PENINSULA, WHILE A RIDGE IS EXPECTED OVER THE
SOUTHWEST CONUS EXTENDING NORTH/NORTHWESTWARD OVER THE NORTHERN INTERMOUNTAIN
WEST, WESTERN CANADA, AND MOST OF ALASKA. THE ENSEMBLE SPAGHETTI CHARTS
GENERALLY INDICATE RELATIVELY LOW SPREAD OVER THE EASTERN LOWER 48 STATES, AND
MODERATE TO LARGE SPREAD OVER THE WESTERN CONUS. TODAY`S 500-HPA BLEND CHART
DEPICTS NEAR TO BELOW NORMAL HEIGHTS OVER THE NORTHEASTERN AND EXTREME
SOUTHWESTERN CONUS, SOUTHWESTERN MAINLAND ALASKA, THE ALASKA PENINSULA, AND THE
EASTERN ALEUTIANS, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE ANTICIPATED OVER THE
REMAINDER OF THE FORECAST DOMAIN.

BELOW NORMAL HEIGHTS AND/OR ANOMALOUS NORTHERLY FLOW TILT THE ODDS TO BELOW
NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL AND EASTERN CONUS. THE EXCEPTION IS
OVER THE FLORIDA PENINSULA WHERE ABOVE NORMAL HEIGHTS FAVOR ABOVE NORMAL
TEMPERATURES. ABOVE NORMAL HEIGHTS ENHANCE PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE WESTERN CONUS, MAINLAND ALASKA, THE WESTERN
ALEUTIANS, AND THE ALASKA PANHANDLE. SURFACE ONSHORE FLOW FAVORS BELOW NORMAL
TEMPERATURES FOR PARTS OF THE SOUTH COAST OF ALASKA.

TROUGHS OVER THE EASTERN CONUS AND CALIFORNIA ENHANCE PROBABILITIES FOR ABOVE
MEDIAN PRECIPITATION FOR MOST OF THE SOUTHERN CONUS WHILE RIDGING OVER THE
INTERIOR WESTERN CONUS AND ANOMALOUS NORTHERLY FLOW FAVOR BELOW MEDIAN
PRECIPITATION FOR MUCH OF THE NORTHERN TIER OF THE CONUS. THE TROUGH OVER
SOUTHWESTERN ALASKA TILTS THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR WESTERN
MAINLAND ALASKA, THE ALEUTIANS, AND THE ALASKA PANHANDLE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 25% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
30% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 10% OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 10% OF YESTERDAY`S OPERATIONAL 12Z
ECMWF CENTERED ON DAY 7, 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
GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND GOOD AGREEMENT AMONG THE
TEMPERATURE AND PRECIPITATION TOOLS.

8-14 DAY OUTLOOK FOR JUN 02 - 08 2017

ENSEMBLE MEAN FORECASTS FROM THE GEFS, ECMWF, AND CANADIAN MODELS GENERALLY
PERSIST THE 500-HPA CIRCULATION PATTERN FROM THE 6-10 DAY PERIOD INTO THE 8-14
DAY PERIOD. ENSEMBLE SPREAD IS MODERATE TO LARGE OVER MOST OF THE FORECAST
DOMAIN. SOME DE-AMPLIFICATION OF ANOMALIES OVER NORTH AMERICA ARE APPARENT AND
RESULT FROM AN INCREASE IN THE ENSEMBLE SPREAD FOR THE 8-14 DAY PERIOD AS WELL
AS INHERENT SMOOTHING WHICH OCCURS OVER THE LONGER 7-DAY AVERAGING PERIOD.
TROUGHS ARE PREDICTED OVER THE SOUTHWEST AND PARTS OF THE CENTRAL GREAT BASIN,
THE EASTERN CONUS, AND THE BERING SEA/ALEUTIANS/ALASKA PENINSULA, WHILE A RIDGE
IS EXPECTED OVER THE INTERIOR NORTHWESTERN CONUS EXTENDING NORTHWESTWARD TO
OVER WESTERN CANADA AND MUCH OF ALASKA. THE WEEK-2 500-HPA BLEND CHART
INDICATES NEAR TO ABOVE NORMAL HEIGHTS FOR MOST OF THE FORECAST DOMAIN EXCEPT
FOR PARTS OF THE INTERIOR EASTERN CONUS AND MUCH OF MAINLAND ALASKA WHERE
SLIGHTLY BELOW NORMAL HEIGHTS ARE ANTICIPATED.

THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FORECAST FOR THE
8-14 DAY PERIOD ARE VERY SIMILAR TO THOSE FORECAST FOR THE 6-10 DAY PERIOD
ALTHOUGH A SLIGHT RETROGRESSION OF THE EASTERN TROUGH LEADS TO A FORECAST OF
NEAR MEDIAN PRECIPITATION (AS OPPOSED TO BELOW MEDIAN) FOR PARTS OF THE
NORTHEAST CONUS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 50% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 11, 40% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 10, AND 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO FAIR AGREEMENT BETWEEN MODEL FORECASTS AND AMONG TEMPERATURE AND
PRECIPITATION TOOLS, BUT INCREASING UNCERTAINTY DUE TO THE EXPECTATION OF SMALL
HEIGHT ANOMALIES.

FORECASTER: RANDY S

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 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:
19520518 - 19660511 - 19660519 - 19850516 - 20030510


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:
19520517 - 19660516 - 19660511 - 20030509 - 19970516


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 31 - JUN 04, 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 02 - 08 2017

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