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705
FXUS06 KWBC 022001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI DECEMBER 02 2016

6-10 DAY OUTLOOK FOR DEC 08 - 12 2016

TODAY`S MODELS SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA FLOW
PATTERN PREDICTED OVER THE FORECAST DOMAIN. A STRONG RIDGE IS PREDICTED OVER
THE BERING SEA AND A STRONG TROUGH IS PREDICTED OVER THE GULF OF ALASKA.
DOWNSTREAM OF THIS TROUGH, A WEAK RIDGE IS FORECAST OVER WESTERN CANADA AND A
TROUGH IS FORECAST OVER THE EASTERN CONUS. TODAY`S MANUAL 500-HPA HEIGHT BLEND
IS WEIGHTED MOST HEAVILY TOWARD THE GFS AND ECMWF ENSEMBLE MEAN SOLUTIONS BASED
ON CONSIDERATIONS OF RECENT SKILL AND ON ANALOG CORRELATIONS, WHICH MEASURE HOW
CLOSELY THE FORECAST PATTERN MATCHES CASES THAT HAVE OCCURRED IN THE PAST.

BELOW NORMAL TEMPERATURES ARE STRONGLY FAVORED FOR MUCH OF THE EASTERN AND
CENTRAL CONUS IN ASSOCIATION WITH A PREDICTED TROUGH. ABOVE NORMAL TEMPERATURES
ARE FAVORED FOR THE SOUTHWESTERN CONUS UNDERNEATH ABOVE NORMAL HEIGHTS.
PREDICTED ANOMALOUS NORTHERLY 500-HPA FLOW LEADS TO INCREASED CHANCES FOR BELOW
NORMAL TEMPERATURES FOR CENTRAL AND SOUTHERN ALASKA, EXCEPT FOR NORTHERN ALASKA.

ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE NORTHERN CONUS,
UNDERNEATH BELOW NORMAL HEIGHTS ASSOCIATED WITH THE TROUGH PREDICTED OVER THE
EASTERN CONUS.  SOUTH OF THE PREDICTED MAIN STORM TRACK, NEAR TO BELOW MEDIAN
PRECIPITATION IS FAVORED FOR THE SOUTHERN CONUS. RIDGING OVER MUCH OF ALASKA
FAVORS BELOW MEDIAN PRECIPITATION.


TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 20% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 20% OF YESTERDAY`S 12Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 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 OVERALL AGREEMENT AMONG THE VARIOUS MODELS AND TOOLS, AND GENERALLY LOW TO
MODERATE SPREAD AMONG THE ENSEMBLE MEMBERS

8-14 DAY OUTLOOK FOR DEC 10 - 16 2016

DURING THE WEEK-2 PERIOD, TODAY`S MODEL SOLUTIONS GENERALLY DEPICT A LESS
AMPLIFIED, MORE PROGRESSIVE PATTERN RELATIVE TO THE 6-10 DAY PERIOD. THE TROUGH
PREDICTED OVER THE EASTERN CONUS DURING THE 6-10 DAY PERIOD IS FORECAST TO
PROGRESS EASTWARD TOWARD THE ATLANTIC COASTS. THE ENSEMBLE MEANS AGREE IN
MAINTAINING BELOW NORMAL HEIGHTS FOR MUCH OF THE NORTHEASTERN CONUS, BUT WITH
REDUCED MAGNITUDE RELATIVE TO THE PRECEDING 6-10 DAY PERIOD. A STRONG RIDGE
CONTINUES TO BE FORECAST OVER THE BERING SEA, RESULTING IN PREDICTED ANOMALOUS
NORTHERLY 500-HPA FLOW DOWNSTREAM OVER MUCH OF ALASKA AND EXTENDING ABOVE
NORMAL 500-HPA HEIGHTS TO THE SOUTHWESTERN CONUS.

BELOW NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE NORTHERN CONUS UNDERNEATH
PREDICTED NEAR TO BELOW NORMAL HEIGHTS. ABOVE NORMAL TEMPERATURES ARE FAVORED
FOR THE SOUTHWESTERN CONUS DUE TO THE ABOVE NORMAL HEIGHTS. CONFIDENCE IS
HIGHER FOR ALASKA WHERE BELOW NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE
STATE UNDERNEATH ANOMALOUS NORTHERLY 500-HPA FLOW.

THE STRONG RIDGE FORECAST OVER THE BERING SEA FAVORS BELOW MEDIAN PRECIPITATION
FOR MOST OF ALASKA. TELECONNECTIONS FROM THE ASSOCIATED POSITIVE ANOMALY CENTER
OVER THE BERING SEA FAVOR ABOVE MEDIAN PRECIPITATION DOWNSTREAM OVER THE
NORTHWESTERN CONUS. ENHANCED PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION ARE
ALSO INDICATED FOR THE NORTH CENTRAL AND EASTERN CONUS UNDERNEATH PREDICTED
CYCLONIC FLOW. BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE SOUTHWESTERN
CONUS, WHICH IS SOUTH OF THE PREDICTED MEAN STORM TRACK.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% 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, 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 LARGE DISAGREEMENTS BETWEEN THE ECMWF ENSEMBLE MEAN AND THE GEFS/CANADIAN
ENSEMBLE MEAN (PARTICULARLY OVER THE WESTERN CONUS).

FORECASTER: QIN GINGER ZHANG

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 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:
19831120 - 19521117 - 19871210 - 19671209 - 19741215


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:
19831123 - 19521117 - 19871210 - 19671210 - 19741214


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 08 - 12 2016

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 10 - 16 2016

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