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FXUS06 KWBC 051901
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 05 2016

6-10 DAY OUTLOOK FOR MAY 11 - 15 2016

RECENT ENSEMBLE MEAN SOLUTIONS ARE IN REASONABLY GOOD AGREEMENT ON THE
PREDICTED 500-HPA CIRCULATION PATTERN OVER NORTH AMERICA DURING THE 6-10 DAY
PERIOD. TROUGHS ARE ANTICIPATED OVER THE EAST-CENTRAL CONUS AND THE BERING SEA,
WHILE A RIDGE IS FORECAST TO BE APPROACHING THE NORTHWEST CONUS EXTENDING
NORTHWARD TO EXTREME WESTERN CANADA AND ALASKA. COMPARED TO THE GFS AND ECMWF
ENSEMBLE MEANS, THE CANADIAN-BASED ENSEMBLE MEANS DEPICT SOMEWHAT HIGHER
HEIGHTS OVER THE CENTRAL CONUS AND WERE GIVEN THE LOWEST WEIGHTS IN TODAY`S
BLENDED HEIGHT CHART. 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 MOST OF THE CONUS AND
ALASKA, AND BELOW NORMAL HEIGHTS OVER THE ALEUTIANS. NEAR TO SLIGHTLY BELOW
NORMAL HEIGHTS ARE EXPECTED NEAR THE GREAT LAKES, OHIO, TENNESSEE AND UPPER AND
MIDDLE MISSISSIPPI VALLEYS.

ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES FOR THE EASTERN
QUARTER OF THE CONUS, ALONG THE GULF COAST, THE WESTERN QUARTER 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 ANTICIPATED OVER THE EAST-CENTRAL CONUS FAVORS ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE CENTRAL AND EASTERN CONUS. THE EXPECTATION OF
UPSLOPE FLOW DEVELOPING LATE IN THE PERIOD OVER THE ROCKIES LEADS TO ENHANCED
PROBABILITIES OF ABOVE MEDIAN PRECIPITATION FOR THE REGION. ANOMALOUS
NORTHWESTERLY FLOW TILTS THE ODDS TO BELOW MEDIAN PRECIPITATION FOR PARTS OF
THE UPPER MISSISSIPPI VALLEY AND GREAT LAKES. ABOVE NORMAL HEIGHTS AND
ANOMALOUS NORTHERLY FLOW TILT THE ODDS TO BELOW MEDIAN PRECIPITATION FOR MUCH
OF THE NORTHWEST CONUS AND THE CENTRAL GREAT BASIN. THE TROUGH OVER THE BERING
SEA AND ANOMALOUS SOUTHERLY FLOW FAVOR ABOVE MEDIAN PRECIPITATION FOR THE
ALEUTIANS AND WESTERN ALASKA. THE RIDGE ANTICIPATED OVER ALASKA ENHANCES
PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR SOUTHEASTERN 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, 30% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 15%
OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
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 MODELS AND FORECAST TOOLS.

8-14 DAY OUTLOOK FOR MAY 13 - 19 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 SPLIT 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. A GENERALLY ZONAL FLOW PATTERN IS ANTICIPATED ACROSS
THE SOUTHERN CONUS. AS WAS TRUE FOR THE 6-10 DAY PERIOD, THE CANADIAN ENSEMBLE
MEANS INDICATE SLIGHTLY HIGHER HEIGHTS OVER THE NORTH-CENTRAL 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 MOST OF THE CONUS AND ALL OF ALASKA, AND NEAR TO
BELOW NORMAL HEIGHTS OVER PARTS OF THE NORTHERN PLAINS, UPPER MISSISSIPPI
VALLEY, AND GREAT LAKES.

THE EXPECTED TEMPERATURE ANOMALY PATTERN IS VERY SIMILAR TO THAT FORECAST FOR
THE 6-10 DAY PERIOD ALTHOUGH THE AREA PROGGED TO HAVE BELOW NORMAL TEMPERATURES
SHIFTS A BIT TO THE NORTHEAST DURING WEEK-2.

THE TROUGH OVER THE EASTERN CONUS AND ANOMALOUS SOUTHWESTERLY FLOW ENHANCE
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE EASTERN CONUS. THE
DEVELOPMENT OF A SOUTHERN JET STREAM ACROSS THE SOUTHERN TIER OF THE COUNTRY
TILT THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE CENTRAL AND
SOUTH-CENTRAL CONUS. UPSLOPE FLOW TILT THE ODDS TO ABOVE MEDIAN PRECIPITATIONS
FOR PARTS OF THE ROCKIES. THE TROUGH NEAR 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 PACIFIC NORTHWEST. ABOVE NORMAL HEIGHTS ENHANCE
PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR PARTS OF CENTRAL CALIFORNIA
AND THE SOUTHWEST.THE TROUGH OVER THE BERING SEA/ALEUTIANS FAVORS ABOVE MEDIAN
PRECIPITATION FOR 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: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 10% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 30% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 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:
19800427 - 19940504 - 19780427 - 20060424 - 19800502


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:
19940503 - 19780427 - 19800429 - 19660506 - 19890508


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 11 - 15 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    B
W MONTANA   A    A     E MONTANA   N    A     WYOMING     N    A
UTAH        A    B     ARIZONA     A    N     COLORADO    B    A
NEW MEXICO  A    N     N DAKOTA    N    N     S DAKOTA    B    N
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     N    A     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   N    N     IOWA        B    N     MISSOURI    N    A
ARKANSAS    N    A     LOUISIANA   A    A     WISCONSIN   N    N
ILLINOIS    N    N     MISSISSIPPI A    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    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    N     AK N SLOPE  A    N
AK ALEUTIAN A    A     AK WESTERN  A    A     AK INT BSN  A    N
AK S INT    A    N     AK SO COAST A    B     AK PNHDL    A    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 13 - 19 2016

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