Prognostic Meteorological Discussion
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FXUS06 KWBC 031902
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 03 2016

6-10 DAY OUTLOOK FOR MAY 09 - 13 2016

RECENT GFS AND CANADIAN 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 NORTHEASTERN CONUS/EASTERN CANADA,
AND THE BERING SEA, WHILE A RIDGE IS FORECAST OVER THE NORTHWEST CONUS
EXTENDING TO WESTERN CANADA AND ALASKA. THE ECMWF-BASED SOLUTIONS ARE QUICKER
TO PROGRESS THE NORTHEAST TROUGH AND PREDICT ADDITIONAL TROUGH ENERGY TO MOVE
TO THE CENTRAL CONUS. GIVEN THE USUAL MODEL BIAS TO LIFT SPRINGTIME TROUGHS OUT
TOO FAST, THE GFS AND CANADIAN SOLUTIONS ARE PREFERRED AND THE ECMWF SOLUTIONS
HAVE BEEN DISCOUNTED FOR NOW. 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 ABOVE NORMAL HEIGHTS OVER THE WESTERN AND
SOUTHEASTERN CONUS, ALONG THE IMMEDIATE EAST COAST, AND MOST OF ALASKA, WITH
NEAR TO BELOW NORMAL HEIGHTS OVER REMAINING U.S. REGIONS AND THE ALEUTIANS.

ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES ARE FORECAST FOR MUCH OF
THE EAST COAST 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 CONUS. ANOMALOUS SOUTHERLY FLOW TILTS THE
ODDS TO ABOVE NORMAL TEMPERATURES FOR ALASKA. BELOW NORMAL HEIGHTS AND
ANOMALOUS NORTHERLY FLOW ENHANCE PROBABILITIES FOR BELOW NORMAL TEMPERATURES
FOR MUCH OF THE SOUTHERN AND CENTRAL ROCKIES AND HIGH PLAINS, AND NEAR THE
GREAT LAKES.

SURFACE HIGH PRESSURE AND ABOVE NORMAL 500-HPA HEIGHTS FAVOR BELOW MEDIAN
PRECIPITATION FOR SOUTHERN FLORIDA. THE TROUGH ANTICIPATED OVER THE NORTHEAST
CONUS AND BELOW NORMAL HEIGHTS ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE SOUTH-CENTRAL AND INTERIOR NORTHEASTERN PORTIONS
OF THE CONUS. ABOVE NORMAL HEIGHTS AND ANOMALOUS NORTHERLY FLOW TILT THE ODDS
TO BELOW MEDIAN PRECIPITATION FOR MUCH OF THE WEST COAST AND CENTRAL PORTIONS
OF THE NORTHERN TIER OF THE U.S. TROUGH ENERGY UNDERCUTTING THE WESTERN RIDGE
FAVORS ABOVE MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHWEST AND CENTRAL AND
SOUTHERN ROCKIES. 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 SOUTHEASTERN ALASKA AND THE ALASKA PANHANDLE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 30% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 20%
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 30% 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 GFS AND CANADIAN MODELS OFFSET BY MODERATE
ENSEMBLE SPREAD AND DIFFERENCES NOTED WITH THE ECMWF ENSEMBLE MEAN SOLUTIONS.

8-14 DAY OUTLOOK FOR MAY 11 - 17 2016

RECENT ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE PREDICTED 500-HPA
CIRCULATION PATTERN OVER NORTH AMERICA DURING THE WEEK-2 PERIOD. TROUGHS ARE
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 ALASKA. THE ECMWF ENSEMBLE MEAN IS A BIT LESS
AMPLIFIED WITH THE TROUGH EXPECTED OVER THE EASTERN CONUS AND THE RIDGE
PREDICTED OVER THE INTERIOR WEST. 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 BELOW NORMAL HEIGHTS OVER THE
INTERIOR NORTHEAST, NEAR THE GREAT LAKES, AND THE ALEUTIANS, WHILE NEAR TO
ABOVE NORMAL HEIGHTS ARE ANTICIPATED OVER THE REMAINDER OF THE CONUS AND ALASKA.

ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES ALONG THE EAST
COAST, OVER THE WESTERN THIRD OF THE CONUS, 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 UPPER AND LOWER MISSISSIPPI VALLEY AND GREAT LAKES, AND PARTS OF
THE CENTRAL AND SOUTHERN PLAINS.

THE TROUGH OVER THE EASTERN CONUS AND ANOMALOUS SOUTHWESTERLY FLOW ENHANCE
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION ALONG THE GULF COAST AND FOR MUCH
OF THE EASTERN AND SOUTH-CENTRAL CONUS. SHORTWAVE ENERGY MOVING OVER THE TOP OF
THE WESTERN RIDGE TILTS THE ODDS TO ABOVE MEDIAN PRECIPITATION  FOR PARTS OF
THE NORTHERN INTERMOUNTAIN WEST AND NORTHERN ROCKIES. THE TROUGH OVER THE
BERING SEA/ALEUTIANS TILTS THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR EXTREME
WESTERN ALASKA AND THE ALEUTIANS. THE RIDGE OVER THE INTERIOR WESTERN CONUS
FAVORS NEAR TO BELOW MEDIAN PRECIPITATION FOR THE NORTHWESTERN  CONUS,
SOUTHEAST ALASKA, AND THE ALASKA PANHANDLE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 10% 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 15% 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:
19800425 - 19800430 - 19910509 - 19910504 - 19730503


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 - 19910508 - 19800430 - 20060422 - 19800505


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 09 - 13 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    N     NEVADA      A    N
W MONTANA   A    N     E MONTANA   A    B     WYOMING     N    N
UTAH        A    A     ARIZONA     A    N     COLORADO    B    A
NEW MEXICO  B    N     N DAKOTA    N    B     S DAKOTA    N    B
NEBRASKA    N    N     KANSAS      B    N     OKLAHOMA    B    A
N TEXAS     B    A     S TEXAS     N    A     W TEXAS     B    N
MINNESOTA   B    B     IOWA        N    N     MISSOURI    N    A
ARKANSAS    B    A     LOUISIANA   N    A     WISCONSIN   B    N
ILLINOIS    N    A     MISSISSIPPI N    A     MICHIGAN    B    N
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    A     ALABAMA     N    A     NEW YORK    N    A
VERMONT     N    A     NEW HAMP    N    A     MAINE       N    A
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        N    A     NEW JERSEY  A    N     W VIRGINIA  N    A
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    N
N CAROLINA  A    N     S CAROLINA  A    N     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    N     AK N SLOPE  A    N
AK ALEUTIAN A    A     AK WESTERN  A    N     AK INT BSN  A    N
AK S INT    A    B     AK SO COAST A    B     AK PNHDL    A    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 11 - 17 2016

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    A     NEVADA      A    N
W MONTANA   A    A     E MONTANA   A    B     WYOMING     A    A
UTAH        A    N     ARIZONA     A    N     COLORADO    A    A
NEW MEXICO  A    N     N DAKOTA    N    B     S DAKOTA    N    B
NEBRASKA    N    N     KANSAS      N    A     OKLAHOMA    B    A
N TEXAS     B    A     S TEXAS     N    A     W TEXAS     N    A
MINNESOTA   N    B     IOWA        N    N     MISSOURI    N    A
ARKANSAS    B    A     LOUISIANA   N    A     WISCONSIN   B    N
ILLINOIS    N    A     MISSISSIPPI N    A     MICHIGAN    B    N
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    A     ALABAMA     N    A     NEW YORK    N    A
VERMONT     A    A     NEW HAMP    A    A     MAINE       A    N
MASS        A    A     CONN        A    A     RHODE IS    A    A
PENN        N    A     NEW JERSEY  N    A     W VIRGINIA  N    A
MARYLAND    N    A     DELAWARE    A    A     VIRGINIA    N    A
N CAROLINA  N    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

                           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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