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FXUS06 KWBC 291933
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON MAY 29 2017

6-10 DAY OUTLOOK FOR JUN 04 - 08 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS FOR THE 6-10 DAY PERIOD ARE IN GOOD AGREEMENT
ON THE 500-HPA CIRCULATION PATTERN PREDICTED OVER NORTH AMERICA. TROUGHS ARE
ANTICIPATED OVER THE EASTERN CONUS, THE WEST COAST, AND NEAR THE ALASKA
PENINSULA, WHILE A RIDGE IS EXPECTED OVER THE NORTHERN HIGH PLAINS EXTENDING
NORTHWARD OVER WEST-CENTRAL CANADA AND ALASKA. TODAY`S 500-HPA BLEND CHART
DEPICTS NEAR TO BELOW NORMAL HEIGHTS OVER MOST OF THE EASTERN CONUS, AND
SOUTHWESTERN ALASKA, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE ANTICIPATED OVER
WESTERN CONUS AND OVER THE REMAINDER OF ALASKA. THE ENSEMBLE SPAGHETTI DIAGRAMS
INDICATE MODERATE TO LARGE SPREAD ACROSS THE MAJORITY OF THE FORECAST DOMAIN.
THE GREATEST WEIGHT FOR THE BLENDED HEIGHT FORECAST WAS GIVEN TO THE ECMWF
ENSEMBLE MEAN BASED ON CONSIDERATIONS OF RECENT SKILL AND ANALOG CORRELATIONS,
WHICH MEASURE HOW CLOSELY THE FORECAST PATTERN MATCHES CASES THAT HAVE OCCURRED
IN THE PAST.

ABOVE NORMAL HEIGHTS ENHANCE PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR
MUCH OF THE WESTERN CONUS. TROUGHING AND ASSOCIATED NEAR TO BELOW NORMAL
HEIGHTS TILT THE ODDS TO NEAR TO BELOW NORMAL TEMPERATURES FOR MUCH OF THE
CENTRAL AND EASTERN CONUS. THE EXCEPTION IS OVER THE FLORIDA PENINSULA WHERE
ABOVE NORMAL SSTS FAVOR ABOVE NORMAL TEMPERATURES. ABOVE NORMAL TEMPERATURES
ARE FAVORED FOR NORTHWESTERN ALASKA AND BELOW NORMAL TEMPERATURES ARE FORECAST
FOR SOUTHEASTERN ALASKA CONSISTENT WITH CALIBRATED TEMPERATURES FROM THE GFS
ENSEMBLE MEMBERS.

A TROUGH OVER THE EASTERN CONUS ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE EASTERN CONUS, WHILE RIDGING OVER THE NORTHERN
HIGH PLAINS AND ANOMALOUS NORTHERLY FLOW FAVOR BELOW MEDIAN PRECIPITATION FOR
MUCH OF THE NORTHERN TIER OF THE CONUS WEST OF THE GREAT LAKES. BELOW MEDIAN
PRECIPITATION IS ALSO FAVORED FOR THE NORTHWESTERN CONUS UNDERNEATH ABOVE
NORMAL HEIGHTS. ABOVE MEDIAN PRECIPITATION IS FORECAST FOR PARTS OF THE GREAT
PLAINS, WHICH IS CONSISTENT WITH PRECIPITATION ESTIMATES FROM THE ECMWF
ENSEMBLE MEMBERS. THE TROUGH NEAR THE ALASKA PENINSULA TILTS THE ODDS TO ABOVE
MEDIAN PRECIPITATION FOR MUCH OF ALASKA.

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, 20%
OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD
AGREEMENT AMONG THE MODEL SOLUTIONS OFFSET BY SOME DISAGREEMENTS AMONG THE
FORECAST TOOLS.

8-14 DAY OUTLOOK FOR JUN 06 - 12 2017

DURING THE WEEK-2 PERIOD, A LOW AMPLITUDE PATTERN IS PREDICTED OVER MUCH OF THE
FORECAST DOMAIN DUE, IN PART, TO DISAGREEMENTS AMONG THE ENSEMBLE MEMBERS. WEAK
TROUGHS ARE FORECAST OVER THE EASTERN CONUS, THE INTERIOR NORTHWEST, AND OVER
THE BERING SEA/ALEUTIANS/ALASKA PENINSULA, WHILE WEAK RIDGING IS INDICATED OVER
PARTS OF MAINLAND ALASKA. TODAY`S 500-HPA BLEND CHART DEPICTS NEAR TO BELOW
NORMAL HEIGHTS OVER THE EASTERN CONUS, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE
ANTICIPATED OVER THE WESTERN CONUS. THE GREATEST WEIGHT WAS GIVEN TO THE ECMWF
ENSEMBLE MEAN BASED ON CONSIDERATIONS OF RECENT SKILL AND ANALOG CORRELATIONS.

THE RESULTING TEMPERATURE OUTLOOK IS VERY SIMILAR TO THAT FOR THE 6-10 DAY
PERIOD. ABOVE NORMAL HEIGHTS FAVOR ABOVE NORMAL TEMPERATURES FOR MUCH OF THE
WESTERN CONUS. BELOW NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE CENTRAL
AND EASTERN CONUS IN ASSOCIATION WITH THE TROUGH OVER THE EASTERN CONUS EXCEPT
FOR THE FLORIDA PENINSULA WHERE ABOVE NORMAL SSTS AND AIR TEMPERATURES ARE
INDICATED. ENHANCED PROBABILITIES FOR BELOW NORMAL TEMPERATURES ARE ALSO
INDICATED FOR PARTS OF SOUTHEASTERN MAINLAND ALASKA CONSISTENT WITH GEFS
REFORECAST GUIDANCE.

PREDICTED CYCLONIC FLOW LEADS TO ENHANCED PROBABILITIES FOR NEAR TO ABOVE
MEDIAN PRECIPITATION FOR THE EASTERN CONUS. ENHANCED PROBABILITIES FOR
BELOW-MEDIAN PRECIPITATION ARE INDICATED FOR THE NORTHWESTERN CONUS EXTENDING
TO PARTS OF THE NORTHERN PLAINS UNDERNEATH ABOVE NORMAL HEIGHTS. ABOVE MEDIAN
PRECIPITATION IS FAVORED FOR MUCH OF ALASKA AHEAD OF THE TROUGH OVER THE BERING
SEA.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 40% 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 FAIR AGREEMENT AMONG THE MODEL SOLUTIONS AND POOR AGREEMENT AMONG THE
FORECAST TOOLS.

FORECASTER: LUKE H

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:
19850516 - 19520516 - 19820611 - 19580517 - 19830527


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:
19820611 - 19850515 - 19520516 - 19830527 - 19580516


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 04 - 08 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 06 - 12 2017

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    B     E MONTANA   A    B     WYOMING     A    N
UTAH        A    N     ARIZONA     A    N     COLORADO    A    N
NEW MEXICO  A    N     N DAKOTA    A    N     S DAKOTA    N    N
NEBRASKA    B    N     KANSAS      B    N     OKLAHOMA    B    N
N TEXAS     B    N     S TEXAS     N    N     W TEXAS     N    N
MINNESOTA   N    N     IOWA        B    N     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   B    N     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    A     NEW HAMP    N    A     MAINE       N    A
MASS        N    A     CONN        N    A     RHODE IS    N    A
PENN        B    A     NEW JERSEY  B    A     W VIRGINIA  B    A
MARYLAND    B    A     DELAWARE    B    A     VIRGINIA    B    A
N CAROLINA  B    A     S CAROLINA  B    A     GEORGIA     B    A
FL PNHDL    N    A     FL PENIN    A    A     AK N SLOPE  A    A
AK ALEUTIAN A    N     AK WESTERN  A    A     AK INT BSN  B    A
AK S INT    B    A     AK SO COAST B    A     AK PNHDL    B    A

                           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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