Prognostic Meteorological Discussion
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FXUS06 KWBC 041902
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 04 2016

6-10 DAY OUTLOOK FOR MAY 10 - 14 2016

RECENT ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE PREDICTED
500-HPA CIRCULATION PATTERN OVER NORTH AMERICA DURING THE 6-10 DAY PERIOD.
TROUGHS ARE ANTICIPATED OVER THE CENTRAL AND EASTERN CONUS AND THE BERING SEA,
WHILE A RIDGE IS FORECAST NEAR THE NORTHWEST CONUS EXTENDING TO EXTREME WESTERN
CANADA AND ALASKA. THE LONG WAVE TROUGH EXPECTED OVER THE CENTRAL AND EASTERN
CONUS IS COMPRISED OF TWO SHORT TROUGHS WITH THE LEAD SHORT WAVE TROUGH
FORECAST TO LIFT OUT FROM THE MARITIME PROVINCES OF CANADA WHILE A SECOND SHORT
WAVE TROUGH MOVES SOUTH FROM WEST-CENTRAL CANADA TO THE CENTRAL CONUS. A WEAK
SHORT WAVE RIDGE BETWEEN THESE SHORT WAVE TROUGHS IS MOST PROMINENT IN THE
ECMWF ENSEMBLE MEAN SOLUTIONS, ESPECIALLY YESTERDAY`S 12Z SOLUTION. THE ECMWF
BASED SOLUTIONS ARE ALSO LESS PROGRESSIVE WITH THE RIDGE FORECAST TO APPROACH
THE NORTHWEST CONUS. COMPARED TO YESTERDAY, OVERALL THE ECMWF-BASED SOLUTIONS
ARE IN A LITTLE BETTER AGREEMENT WITH THE RECENT RUNS FROM THE GFS AND CANADIAN
ENSEMBLE MEANS TODAY. THE ENSEMBLE SPAGHETTI CHARTS GENERALLY INDICATE LOW TO
MODERATE SPREAD OVER THE EASTERN AND CENTRAL CONUS, AND MODERATE TO LARGE
SPREAD OVER THE WESTERN CONUS AND EASTERN PACIFIC. TODAY`S 500-HPA BLENDED
HEIGHT CHART INDICATES NEAR TO ABOVE NORMAL HEIGHTS OVER THE CONUS AND MOST OF
ALASKA, AND BELOW NORMAL HEIGHTS OVER THE ALEUTIANS.

ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES ARE FORECAST FOR MUCH OF
THE EASTERN QUARTER OF THE CONUS DUE TO ABOVE NORMAL HEIGHTS AND THE
EXPECTATION OF SURFACE HIGH PRESSURE OFF THE SOUTHEAST COAST. ABOVE NORMAL
HEIGHTS FAVOR ABOVE NORMAL TEMPERATURES FOR MUCH OF THE WESTERN QUARTER OF THE
CONUS. ANOMALOUS SOUTHERLY FLOW TILTS THE ODDS TO ABOVE NORMAL TEMPERATURES FOR
ALASKA. THE TROUGH PREDICTED FOR THE CENTRAL CONUS ENHANCES PROBABILITIES FOR
BELOW NORMAL TEMPERATURES FOR PARTS OF THE NORTH-CENTRAL AND CENTRAL CONUS.

THE TROUGH ANTICIPATED OVER THE CENTRAL AND EASTERN CONUS ENHANCE PROBABILITIES
FOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE CENTRAL AND EASTERN CONUS. ABOVE
NORMAL HEIGHTS AND ANOMALOUS NORTHERLY FLOW TILT THE ODDS TO BELOW MEDIAN
PRECIPITATION FOR MUCH OF THE NORTHWEST CONUS AND CENTRAL PORTIONS OF THE
NORTHERN TIER OF THE U.S. THE TROUGH OVER THE BERING SEA AND ANOMALOUS
SOUTHERLY FLOW FAVOR ABOVE MEDIAN PRECIPITATION FOR THE ALEUTIANS AND
NORTHWESTERN ALASKA. THE RIDGE ANTICIPATED OVER ALASKA ENHANCES PROBABILITIES
FOR BELOW MEDIAN PRECIPITATION FOR EASTERN ALASKA AND THE ALASKA PANHANDLE.

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


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE MODELS OFFSET BY MODERATE ENSEMBLE SPREAD AND
SOME DIFFERENCES NOTED WITH THE ECMWF ENSEMBLE MEAN SOLUTIONS.

8-14 DAY OUTLOOK FOR MAY 12 - 18 2016

RECENT ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 500-HPA
CIRCULATION PATTERN OVER NORTH AMERICA DURING THE WEEK-2 PERIOD. A LOW
AMPLITUDE FLOW PATTERN IS ANTICIPATED WITH TROUGHS EXPECTED OVER THE EASTERN
CONUS, ALONG THE WEST COAST, AND OVER THE BERING SEA/ALEUTIANS, WHILE A RIDGE
IS ANTICIPATED OVER THE INTERIOR WESTERN CONUS EXTENDING NORTHWESTWARD TO
WESTERN CANADA AND ALASKA. THE ECMWF ENSEMBLE MEAN IS A BIT LESS AMPLIFIED WITH
THE TROUGH EXPECTED OVER THE EASTERN CONUS. DESPITE THE GENERAL AGREEMENT AMONG
THE ENSEMBLE MEAN SOLUTIONS, THE ENSEMBLE SPAGHETTI CHARTS INDICATE MODERATE
SPREAD OVER THE EASTERN CONUS, WHILE MODERATE TO LARGE SPREAD IS DEPICTED OVER
THE WESTERN CONUS AND THE EAST PACIFIC. THE BLENDED HEIGHT CHART DEPICTS WEAK
ANOMALIES ACROSS MOST OF THE CONUS, WITH NEAR TO ABOVE NORMAL HEIGHTS OVER THE
THE CONUS AND ALASKA, AND NEAR TO BELOW NORMAL HEIGHTS OVER THE ALEUTIANS.

ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES ALONG THE EAST
COAST, OVER THE WESTERN THIRD OF THE CONUS, PARTS OF THE SOUTHERN PLAINS, AND
ALASKA. ABOVE NORMAL SEA SURFACE TEMPERATURES FAVOR ABOVE NORMAL TEMPERATURES
FOR THE ALEUTIANS. THE TROUGH OVER THE EASTERN CONUS TILTS THE ODDS TO BELOW
NORMAL TEMPERATURES FOR PARTS OF THE CENTRAL CONUS.

THE TROUGH OVER THE EASTERN CONUS AND ANOMALOUS SOUTHWESTERLY FLOW ENHANCE
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE EASTERN AND
SOUTH-CENTRAL CONUS. THE TROUGH APPROACHING THE WEST COAST FAVORS ABOVE MEDIAN
PRECIPITATION FOR PARTS OF NORTHERN CALIFORNIA AND PARTS OF THE CENTRAL GREAT
BASIN. ANOMALOUS NORTHWESTERLY FLOW TILTS THE ODDS TO BELOW MEDIAN
PRECIPITATION FOR PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY.
THE TROUGH OVER THE BERING SEA/ALEUTIANS FAVORS ABOVE MEDIAN PRECIPITATION FOR
EXTREME WESTERN ALASKA AND THE ALEUTIANS. THE RIDGE OVER ALASKA ENHANCES
PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR EASTERN PORTIONS OF THE STATE
AND THE ALASKA PANHANDLE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, 30% 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 GOOD AGREEMENT AMONG THE MODEL HEIGHT FORECASTS OFFSET BY RELATIVELY LARGE
ENSEMBLE SPREAD, LOW MAGNITUDE HEIGHT ANOMALIES, AND DAY TO DAY VARIABILITY
AMONG THE PRECIPITATION TOOLS.

FORECASTER: RANDY SCHECHTER

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 MAY
19

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:
19800426 - 20060423 - 19730502 - 19810518 - 19940504


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:
19800425 - 19800504 - 20060423 - 19910505 - 19940503


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 10 - 14 2016

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    N
W MONTANA   N    N     E MONTANA   N    N     WYOMING     N    N
UTAH        A    N     ARIZONA     A    N     COLORADO    N    A
NEW MEXICO  N    N     N DAKOTA    B    B     S DAKOTA    N    N
NEBRASKA    N    A     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     N    A     S TEXAS     N    A     W TEXAS     N    N
MINNESOTA   B    B     IOWA        N    N     MISSOURI    N    A
ARKANSAS    N    A     LOUISIANA   N    A     WISCONSIN   N    B
ILLINOIS    N    A     MISSISSIPPI N    A     MICHIGAN    N    N
INDIANA     N    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    N
MASS        A    N     CONN        A    N     RHODE IS    A    N
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  A    N
AK ALEUTIAN A    A     AK WESTERN  A    N     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 MAY 12 - 18 2016

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    N     OREGON      A    N     NRN CALIF   A    A
SRN CALIF   A    N     IDAHO       A    A     NEVADA      A    A
W MONTANA   A    N     E MONTANA   A    N     WYOMING     A    A
UTAH        A    A     ARIZONA     A    N     COLORADO    A    A
NEW MEXICO  A    A     N DAKOTA    N    B     S DAKOTA    N    N
NEBRASKA    N    A     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     N    A     S TEXAS     A    A     W TEXAS     A    A
MINNESOTA   N    B     IOWA        B    A     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   N    A     WISCONSIN   B    N
ILLINOIS    B    A     MISSISSIPPI N    A     MICHIGAN    B    N
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    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  A    B
AK ALEUTIAN A    A     AK WESTERN  A    A     AK INT BSN  A    B
AK S INT    A    N     AK SO COAST A    N     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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