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FXUS06 KWBC 231904
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 23 2017

6-10 DAY OUTLOOK FOR MAY 29 - JUN 02, 2017

RECENT ENSEMBLE MEAN SOLUTIONS OF THE NCEP GEFS, ECMWF AND CANADIAN MODELS ARE
IN GOOD AGREEMENT ON THE LARGE SCALE CIRCULATION PATTERN FORECAST FOR THE 6-10
DAY PERIOD. MODELS FORECAST RELATIVE TROUGHING OVER THE ALEUTIAN ISLANDS, WITH
A RIDGE  EXTENDING FROM EASTERN ALASKA SOUTHWARD ALONG THE PACIFIC COAST OF
CANADA INTO THE WESTERN CONUS, A SHORTWAVE TROUGH NEAR THE COAST OF CALIFORNIA,
AND A TROUGH OVER EASTERN NORTH AMERICA. HIGH RESOLUTION MODEL RUNS OF THE NCEP
GFS AND ECMWF PREDICT SIMILAR FLOW PATTERNS. TODAY`S MANUAL BLEND OF THE
500-HPA HEIGHT FIELD INDICATES ABOVE NORMAL HEIGHT ANOMALIES OVER ALASKA, THE
WESTERN CONUS, AND ALONG THE GULF COAST.

ABOVE NORMAL TEMPERATURES ARE FORECAST FOR MUCH OF THE WESTERN U.S. TO THE WEST
OF THE ROCKY MOUNTAINS, WHERE ATMOSPHERIC HEIGHTS ARE ABOVE NORMAL, WITH
GREATEST PROBABILITIES FOR THE PACIFIC NORTHWEST. WITH A PREDICTED TROUGH TO
THE EAST AND NORTHERLY MID-LEVEL ATMOSPHERIC FLOW OVER THE CENTRAL U.S., BELOW
NORMAL TEMPERATURES ARE MOST LIKELY FROM JUST EAST OF THE ROCKY MOUNTAINS TO
THE GREAT LAKES REGION, AS WELL AS THE MISSISSIPPI AND OHIO VALLEYS. ABOVE
NORMAL TEMPERATURES ARE MOST LIKELY FOR PARTS OF THE GULF AND ATLANTIC COASTS,
WHERE HEIGHTS ARE PREDICTED TO BE NEAR TO ABOVE NORMAL. ABOVE NORMAL
TEMPERATURES ARE PREDICTED TO BE MOST LIKELY FOR MOST OF ALASKA, WHILE BELOW
NORMAL TEMPERATURES ARE MORE LIKELY FOR SOME AREAS OF THE SOUTH COAST,
FOLLOWING REFORECAST CALIBRATIONS OF THE ECMWF AND GEFS ENSEMBLE PREDICTION
SYSTEMS.

TROUGHING TO THE WEST OF ALASKA LEADS TO A FORECAST OF ABOVE MEDIAN
PRECIPITATION FOR WESTERN REGIONS OF THE STATE, WHILE BELOW MEDIAN
PRECIPITATION IS MORE LIKELY FOR EASTERN REGIONS OF THE STATE, INCLUDING THE
ALASKA PANHANDLE, UNDER THE PREDICTED MID-LEVEL RIDGE. ENHANCED PROBABILITIES
OF BELOW MEDIAN PRECIPITATION EXTEND SOUTHWARD INTO THE PACIFIC NORTHWEST AND
THE NORTHERN PLAINS. ABOVE MEDIAN PRECIPITATION IS MOST LIKELY FOR A LARGE AREA
OF THE CONUS FROM THE SOUTHERN AND CENTRAL ROCKIES ACROSS THE SOUTHERN PLAINS
INTO MOST OF THE CONUS TO THE EAST OF THE MISSISSIPPI VALLEY.

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, 50%
OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 20% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


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 MAY 31 - JUN 06, 2017

ENSEMBLE MEAN FORECASTS FROM THE NCEP GEFS, ECMWF AND CANADIAN MODELS SOMEWHAT
PERSIST THE CIRCULATION PATTERN FROM THE 6-10 DAY PERIOD INTO THE 8-14 DAY
PERIOD, WITH SOME DE-AMPLIFICATION OF ANOMALIES OVER NORTH AMERICA RESULTING
FROM AN INCREASE IN THE ENSEMBLE SPREAD AT LEAD TIMES OF THE 8-14 DAY PERIOD
FORECAST. RELATIVE TROUGHING CONTINUES TO BE FORECAST TO THE WEST OF ALASKA,
WHILE RIDGING CONTINUES TO BE FORECAST FROM EASTERN ALASKA SOUTHWARD INTO THE
PACIFIC NORTHWEST. A SHORTWAVE TROUGH IS PREDICTED NEAR THE PACIFIC COAST OF
CALIFORNIA IN THE 8-14 DAY PERIOD, WHILE THE TROUGH PREDICTED OVER THE EASTERN
CONUS IS MUCH LESS AMPLIFIED. THE TEMPERATURE AND PRECIPITATION PATTERNS
FORECAST FOR THE 8-14 DAY PERIOD ARE SOMEWHAT SIMILAR TO THE 6-10 DAY PERIOD
FORECAST, WITH SOME SLIGHT CHANGES RESULTING FROM CHANGES IN THE CIRCULATION
FORECAST.

ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES CONTINUE TO BE FORECAST FOR
MOST OF ALASKA. BELOW NORMAL TEMPERATURES CONTINUE TO BE PREDICTED FOR PARTS OF
THE SOUTH COAST OF THE STATE BY THE ECMWF AND GEFS ENSEMBLE PREDICTION SYSTEMS.
ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES ARE FORECAST DURING THE
8-14 DAY PERIOD FOR MUCH OF THE NORTHWEST CONUS, WITH NEAR NORMAL TEMPERATURES
MORE LIKELY FOR MUCH OF SOUTHERN CALIFORNIA, WHERE A SHORTWAVE TROUGH IS
PREDICTED. BELOW NORMAL TEMPERATURES CONTINUE TO BE MOST LIKELY FOR MOST AREAS
TO THE EAST OF THE ROCKIES, INCLUDING MUCH OF THE CENTRAL AND SOUTHERN PLAINS,
AS WELL AS THE MISSISSIPPI AND OHIO VALLEYS, WHILE ABOVE NORMAL TEMPERATURES
CONTINUE TO BE MOST LIKELY FOR PARTS OF THE GULF AND ATLANTIC COASTS.

ABOVE MEDIAN PRECIPITATION IS MOST LIKELY ACROSS A SIMILAR LARGE AREA OF THE
CONUS TO THE EAST OF THE ROCKY MOUNTAINS. PROBABILITIES OF ABOVE MEDIAN
PRECIPITATION ARE GREATER IN THE 8-14 DAY PERIOD FOR PARTS OF THE GREAT BASIN
AND NORTHERN CENTRAL ROCKIES, TO THE EAST OF A PREDICTED SHORTWAVE TROUGH.
ABOVE MEDIAN PRECIPITATION CONTINUES TO BE MOST LIKELY FOR NORTHERN AND WESTERN
REGIONS OF ALASKA, WHILE BELOW MEDIAN PRECIPITATION IS MOST LIKELY FOR
SOUTHEASTERN PARTS OF THE STATE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 50% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% OF
TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO SOME DISAGREEMENT BETWEEN MODEL FORECASTS AND AMONG TEMPERATURE AND
PRECIPITATION TOOLS, AND INCREASING UNCERTAINTY AS INDICATED BY THE ENSEMBLE
SPREAD.

FORECASTER: DAN C

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:
19850514 - 19520517 - 19950526 - 20070530 - 19790512


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:
19950525 - 19850514 - 19520517 - 20010523 - 20070530


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 29 - JUN 02, 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 31 - JUN 06, 2017

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