Prognostic Meteorological Discussion
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FXUS06 KWBC 061901
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI MAY 06 2016

6-10 DAY OUTLOOK FOR MAY 12 - 16 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 EAST-CENTRAL CONUS AND THE BERING SEA, WHILE
RIDGES ARE EXPECTED OVER THE INTERIOR WESTERN CONUS AND WESTERN CANADA AND
ALASKA. A WEAK SPLIT-FLOW PATTERN IS INDICATED AS TROUGH ENERGY UNDERCUTS THE
RIDGE FORECAST OVER WESTERN CANADA AND ALASKA. COMPARED TO THE GFS AND CANADIAN
ENSEMBLE MEANS, THE ECMWF-BASED ENSEMBLE MEANS DEPICT SOMEWHAT HIGHER HEIGHTS
OVER THE NORTHEAST CONUS. 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 BELOW NORMAL HEIGHTS OVER THE NORTHEAST CONUS,
THE UPPER AND MIDDLE MISSISSIPPI VALLEY, AND THE GREAT LAKES/OHIO VALLEY, AND
NEAR TO ABOVE NORMAL HEIGHTS OVER THE REMAINDER OF THE CONUS AND ALASKA.

ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES FOR THE EAST
COAST AND SOUTHEASTERN CONUS, 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 EAST-CENTRAL CONUS
TILTS THE ODDS TO BELOW NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL CONUS.

THE TROUGH ANTICIPATED OVER THE EAST-CENTRAL CONUS FAVORS ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE EASTERN AND SOUTH-CENTRAL CONUS. THE EXPECTATION
OF UPSLOPE FLOW DEVELOPING LATE IN THE PERIOD OVER THE CENTRAL AND SOUTHERN
ROCKIES LEADS TO ENHANCED PROBABILITIES OF ABOVE MEDIAN PRECIPITATION FOR THOSE
REGIONS. ANOMALOUS NORTHWESTERLY FLOW TILTS THE ODDS TO BELOW MEDIAN
PRECIPITATION FOR PARTS OF THE NORTHERN AND SOUTHERN PLAINS AND UPPER AND
MIDDLE MISSISSIPPI VALLEY. ABOVE NORMAL HEIGHTS AND ANOMALOUS NORTHEASTERLY
FLOW TILT THE ODDS TO BELOW MEDIAN PRECIPITATION FOR MUCH OF THE NORTHWEST
CONUS, THE CENTRAL GREAT BASIN, AND PARTS OF THE SOUTHWEST. 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 25% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 15% OF YESTERDAY`S 12Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 10% OF TODAY`S OPERATIONAL 0Z ECMWF
CENTERED ON DAY 8, 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8,
AND 20% 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 14 - 20 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 OR JUST OFF 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. 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 AND AS THE FLOW PATTERN
DEAMPLIFIES, A WARMER PATTERN IS ANTICIPATED FOR THE WESTERN GULF COAST.

THE TROUGH OVER THE EASTERN CONUS AND ANOMALOUS SOUTHWESTERLY FLOW ENHANCE
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR MAINE. THE WEAK JET STREAM
ACROSS THE SOUTHERN TIER OF THE COUNTRY TILTS 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.
ANOMALOUS NORTHERLY FLOW TILTS THE ODDS TO BELOW MEDIAN PRECIPITATION FOR
WESTERN AND CENTRAL SECTIONS OF THE NORTHERN TIER OF THE CONUS. 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: 15% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 15% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 20% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 20% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 10% 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, VERY 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:
19800430 - 19940506 - 19780427 - 20060424 - 19930511


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:
19800430 - 19940504 - 19780428 - 19890509 - 19660507


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 12 - 16 2016

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    B     NEVADA      A    B
W MONTANA   A    B     E MONTANA   B    B     WYOMING     N    N
UTAH        A    N     ARIZONA     A    N     COLORADO    B    A
NEW MEXICO  A    A     N DAKOTA    B    B     S DAKOTA    B    B
NEBRASKA    B    N     KANSAS      B    N     OKLAHOMA    B    A
N TEXAS     N    A     S TEXAS     N    A     W TEXAS     B    A
MINNESOTA   B    B     IOWA        B    B     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   N    A     WISCONSIN   B    N
ILLINOIS    B    N     MISSISSIPPI N    A     MICHIGAN    B    N
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    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        N    A     NEW JERSEY  A    A     W VIRGINIA  N    A
MARYLAND    N    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    A
AK ALEUTIAN A    A     AK WESTERN  A    A     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 14 - 20 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    B     E MONTANA   N    B     WYOMING     N    A
UTAH        A    N     ARIZONA     A    N     COLORADO    A    A
NEW MEXICO  A    N     N DAKOTA    B    B     S DAKOTA    B    N
NEBRASKA    B    A     KANSAS      N    A     OKLAHOMA    N    A
N TEXAS     A    A     S TEXAS     A    A     W TEXAS     A    A
MINNESOTA   B    B     IOWA        B    N     MISSOURI    B    A
ARKANSAS    N    A     LOUISIANA   A    A     WISCONSIN   B    B
ILLINOIS    B    A     MISSISSIPPI A    A     MICHIGAN    B    N
INDIANA     B    N     OHIO        B    N     KENTUCKY    B    A
TENNESSEE   N    A     ALABAMA     A    A     NEW YORK    N    N
VERMONT     N    N     NEW HAMP    N    N     MAINE       N    A
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        B    N     NEW JERSEY  A    N     W VIRGINIA  B    N
MARYLAND    N    N     DELAWARE    A    N     VIRGINIA    N    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    N     AK WESTERN  A    A     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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