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FXUS06 KWBC 202033
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST MON NOVEMBER 20 2017

6-10 DAY OUTLOOK FOR NOV 26 - 30 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN FOR THE 6-10 DAY PERIOD OVER NORTH AMERICA. A RIDGE IS
FORECAST OVER ALASKA, WHILE A TROUGH IS PREDICTED OVER THE GULF OF ALASKA,
EXTENDING INTO THE NORTHEAST PACIFIC. ANOTHER TROUGH IS FORECAST OVER THE
EASTERN CONUS. ABOVE NORMAL 500-HPA HEIGHTS ARE PREDICTED OVER ALASKA AND
ACROSS THE WESTERN CONUS. BELOW NORMAL 500-HPA HEIGHTS ARE FORECAST OVER THE
EASTERN CONUS.

ABOVE NORMAL TEMPERATURES ARE FAVORED FOR MOST OF MAINLAND ALASKA AND THE
ALEUTIANS, AS WELL AS THE WESTERN AND CENTRAL CONUS UNDER PREDICTED ABOVE
NORMAL 500-HPA HEIGHTS. BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE EASTERN
CONUS CORRESPONDING TO THE BELOW NORMAL 500-HPA HEIGHTS AND ANOMALOUS NORTHERLY
FLOW.

ABOVE NORMAL PRECIPITATION IS FAVORED FOR WESTERN MAINLAND ALASKA AND THE
ALEUTIANS, DUE TO THE FORECAST TROUGH UPSTREAM AND ONSHORE FLOW. BELOW NORMAL
PRECIPITATION IS MOST LIKELY FOR EASTERN MAINLAND ALASKA AND THE PANHANDLE,
AHEAD OF A PREDICTED RIDGE AND OFFSHORE FLOW. ABOVE NORMAL PRECIPITATION IS
MOST LIKELY FOR THE NORTHWESTERN CONUS, NORTHERN AND CENTRAL CALIFORNIA, AND
MUCH OF NEVADA FOR AHEAD OF THE PREDICTED TROUGH OVER THE NORTH PACIFIC.
PROBABILITIES OF BELOW AND NEAR NORMAL PRECIPITATION ARE ELEVATED FOR MOST OF
THE CENTRAL AND EASTERN CONUS.

THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 20% 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, 20% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 20% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT ON THE EXPECTED CIRCULATION PATTERN


8-14 DAY OUTLOOK FOR NOV 28 - DEC 04, 2017

THE OVERALL 500-HPA CIRCULATION PATTERN PREDICTED FOR THE WEEK 2 PERIOD IS
SIMILAR TO THE 6-10 DAY PERIOD ACROSS NORTH AMERICA. THE ENSEMBLE SPAGHETTI
DIAGRAMS INDICATE MODERATE TO LARGE SPREAD ACROSS THE MAJORITY OF THE FORECAST
DOMAIN. THE GREATEST WEIGHT FOR THE BLENDED 500-HPA HEIGHT FIELD WAS GIVEN TO
THE ECMWF 0Z ENSEMBLE MEAN BASED ON CONSIDERATIONS OF RECENT SKILL AND ANALOG
CORRELATIONS.

ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES FOR MAINLAND
ALASKA AND THE ALEUTIANS. NEAR TO ABOVE NORMAL HEIGHTS, ENHANCE PROBABILITIES
OF ABOVE NORMAL TEMPERATURES FOR THE MOST OF THE CONUS EXCEPT FOR BELOW NORMAL
TEMPERATURE IN NORTHERN NEW ENGLAND.

ABOVE NORMAL PRECIPITATION IS SLIGHTLY FAVORED FOR THE GREAT BASIN, THE
NORTHERN AND CENTRAL ROCKIES, THE NORTHERN AND CENTRAL PLAINS, MUCH OF THE
MISSISSIPPI VALLEY, THE GREAT LAKES, AND THE OHIO AND TENNESSEE VALLEY,
CONSISTENT TO ESTIMATES FROM THE ECMWF AND GEFS REFORECAST TOOLS. BELOW NORMAL
PRECIPITATION IS LIKELY FOR THE NORTHWEST, PARTS OF THE SOUTHWESTERN CONUS, AND
THE MIDDLE AND SOUTH ATLANTIC COAST STATES. EASTERN ALASKA IS FAVORED TO HAVE
BELOW OR NEAR NORMAL PRECIPITATION, WHILE ABOVE NORMAL PRECIPITATION IS LIKELY
FOR WESTERN MAINLAND ALASKA AND THE ALEUTIANS, UNDER PREDICTED ONSHORE AND
CYCLONIC FLOW.

THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 5% 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, 30% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 20% OF YESTERDAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, AND 5% 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 AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS ON THE 500-HPA CIRCULATION
PATTERN DURING WEEK 2, OFFSET BY MODERATE TO LARGE SPREAD AMONG THE ENSEMBLE
MEMBERS

FORECASTER: QIN Z

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
DECEMBER 21

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:
19701122 - 19901123 - 19541203 - 19731110 - 19711107


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:
19701121 - 19701126 - 19711106 - 19961105 - 19541202


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 26 - 30 2017

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     OREGON      A    A     NRN CALIF   A    A
SRN CALIF   A    N     IDAHO       A    A     NEVADA      A    A
W MONTANA   A    A     E MONTANA   A    A     WYOMING     A    A
UTAH        A    N     ARIZONA     A    B     COLORADO    A    B
NEW MEXICO  A    B     N DAKOTA    A    A     S DAKOTA    A    N
NEBRASKA    A    B     KANSAS      A    B     OKLAHOMA    A    B
N TEXAS     A    B     S TEXAS     A    B     W TEXAS     A    B
MINNESOTA   A    N     IOWA        A    B     MISSOURI    A    B
ARKANSAS    A    B     LOUISIANA   A    B     WISCONSIN   N    B
ILLINOIS    A    B     MISSISSIPPI A    B     MICHIGAN    B    B
INDIANA     N    B     OHIO        B    B     KENTUCKY    B    B
TENNESSEE   B    B     ALABAMA     N    B     NEW YORK    B    B
VERMONT     B    B     NEW HAMP    B    B     MAINE       B    N
MASS        B    B     CONN        B    B     RHODE IS    B    B
PENN        B    B     NEW JERSEY  B    B     W VIRGINIA  B    B
MARYLAND    B    B     DELAWARE    B    B     VIRGINIA    B    B
N CAROLINA  B    B     S CAROLINA  B    B     GEORGIA     B    B
FL PNHDL    B    B     FL PENIN    B    B     AK N SLOPE  A    A
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    B    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 28 - DEC 04, 2017

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