Prognostic Meteorological Discussion
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FXUS06 KWBC 062001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE DECEMBER 06 2016

6-10 DAY OUTLOOK FOR DEC 12 - 16 2016

TODAY`S MODELS EXHIBIT GOOD AGREEMENT ON THE PREDICTED 500-HPA HEIGHT PATTERN.
ABOVE NORMAL HEIGHTS ARE PREDICTED OVER THE MOST OF ALASKA AND MOST OF THE
SOUTHERN TIER OF THE CONUS. TROUGHING OVER CANADA AND THE NORTHERN CONUS ARE
ALSO AGREED UPON IN THE MODELS. THE OVERALL PATTERNS AGREE ON A BLOCK OVER THE
CENTRAL PACIFIC AND AN ENHANCED JET OVER THE CONUS. TODAY`S OFFICIAL 500-HPA
MANUAL HEIGHT BLEND CONSISTS OF THE ENSEMBLE MEAN SOLUTIONS, AS WELL AS THE 06Z
GFS OPERATIONAL SOLUTION DUE TO CONSIDERATIONS OF RECENT SKILL AND ON ANALOG
CORRELATIONS, WHICH MEASURE HOW CLOSELY THE PREDICTED PATTERN MATCHES CASES
THAT HAVE OCCURRED IN THE PAST.

PREDICTED RIDGING OVER THE BERING STRAIT FAVORS BELOW NORMAL TEMPERATURES AS
COLD AIR IS FORECAST TO FUNNEL SOUTHWARD OVER MOST OF ALASKA AND ACROSS CANADA
TO THE NORTHERN CONUS. ABOVE NORMAL SSTS FAVOR ABOVE NORMAL TEMPERATURES FOR
PORTIONS OF NORTHERN COASTAL ALASKA AND THE ALEUTIANS. ABOVE AVERAGE HEIGHTS
AND LOW-LEVEL HIGH PRESSURE IMPLY ABOVE NORMAL TEMPERATURES FOR THE SOUTHERN
TIER OF THE CONUS.

THE RIDGING OVER THE BERING STRAIT FAVORS A DRIER PATTERN OVER ALASKA AS STORMS
WOULD BE DEFLECTED SOUTHWARD. THE SOUTHWARD DISPLACED STORM TRACK, ALIGNED WITH
THE SOUTHERN PERIPHERY OF THE TROUGH OVER CENTRAL CANADA, FAVORS ABOVE MEDIAN
PRECIPITATION FOR THE NORTHWESTERN, NORTH CENTRAL, AND EASTERN CONUS. THE
SLIGHT RIDGING FORECAST OVER THE SOUTHWEST FAVORS BELOW MEDIAN PRECIPITATION
FROM ARIZONA TO TEXAS.

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 14 - 20 2016

DURING THE 8-14 DAY PERIOD, MODEL AGREEMENT REMAINS GOOD, ALTHOUGH
DISCREPANCIES GROW COMPARED TO THE 6-10 DAY PERIOD. A BLOCKING STRUCTURE IS
STILL PREDICTED OVER THE CENTRAL PACIFIC WITH TROUGHING NEAR HAWAII AND RIDGING
OVER THE BERING SEA. TROUGHING IS PREDICTED OVER CENTRAL CANADA. THE MODELS
DISAGREE ON THE SOUTHERN EXTENT OF THE TROUGHING, WITH THE EUROPEAN ENSEMBLE
MEAN DROPPING HEIGHTS OVER THE SOUTHEAST CONUS AND RAISING 500-HPA HEIGHTS OVER
THE WESTERN CONUS. THE GFS MAINTAINS A BROAD TROUGH OVER MUCH OF THE CONUS WITH
ONLY A MODERATE RAISING OF HEIGHTS FROM THE 6-10 DAY PERIOD. THE 500-HPA MANUAL
BLEND IS BASED ON THE EUROPEAN ENSEMBLE MEANS AND GFS ENSEMBLE SOLUTIONS. THE
ENSEMBLE SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE MAJORITY OF THE
FORECAST DOMAIN.

THE RESULTANT BLEND FAVORS BELOW NORMAL TEMPERATURES OVER MUCH OF ALASKA AND
THE NORTHERN CONUS AS COLD AIR IS LIKELY TO FLOW SOUTHWARD, EAST OF THE
PREDICTED RIDGE OVER THE BERING SEA. THE COLDER AIR IS EXPECTED TO WORK
SOUTHWARD TO THE GREAT PLAINS, GREAT LAKES REGION, THE MISSISSIPPI VALLEY,
MID-ATLANTIC, AND THE NORTHEAST. THERE ARE ENHANCED PROBABILITIES OF ABOVE
NORMAL TEMPERATURES FOR THE EASTERN GULF COAST REGION AND THE FLORIDA PENINSULA
AHEAD OF PREDICTED TROUGHING. WITH THE HEIGHTS PREDICTED TO RISE SLIGHTLY OVER
THE WESTERN CONUS, TEMPERATURES ARE EXPECTED TO BE ABOVE NORMAL OVER THE GREAT
BASIN AND SOUTHWEST.

RIDGING PREDICTED OVER THE SOUTH CENTRAL FAVORS BELOW NORMAL PRECIPITATION. AN
ACTIVE STORM TRACK IS PREDICTED FROM THE PACIFIC COAST TO THE GREAT LAKES
REGION, FAVORING ABOVE MEDIAN PRECIPITATION IN THOSE REGIONS. FRONTS ASSOCIATED
WITH THE STORM TRACK FAVOR ABOVE MEDIAN PRECIPITATION FOR THE EASTERN CONUS,
ALTHOUGH PROBABILITIES ARE LOWER BECAUSE UNCERTAINTY IS HIGHER OVER THAT
REGION. RIDGING OVER MUCH OF ALASKA FAVORS BELOW MEDIAN PRECIPITATION.

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: AVERAGE, 3 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT, TEMPERED BY DISAGREEMENTS IN THE PREDICTED HEIGHTS OVER
THE SOUTHEAST 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:
19871212 - 19681219 - 19671217 - 19731119 - 19611207


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:
19681219 - 19671219 - 20051202 - 19551115 - 19871212


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

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    A     OREGON      B    A     NRN CALIF   A    A
SRN CALIF   A    N     IDAHO       B    A     NEVADA      A    A
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    A
UTAH        A    A     ARIZONA     A    B     COLORADO    B    A
NEW MEXICO  A    B     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    B    A     KANSAS      B    N     OKLAHOMA    B    B
N TEXAS     N    B     S TEXAS     A    B     W TEXAS     A    B
MINNESOTA   B    A     IOWA        B    A     MISSOURI    B    N
ARKANSAS    B    N     LOUISIANA   A    A     WISCONSIN   B    A
ILLINOIS    B    A     MISSISSIPPI A    A     MICHIGAN    B    A
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A
TENNESSEE   N    A     ALABAMA     A    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    N    A     DELAWARE    N    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    B
AK ALEUTIAN A    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 14 - 20 2016

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    A     OREGON      B    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        A    A     ARIZONA     A    B     COLORADO    A    A
NEW MEXICO  A    B     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    B    A     KANSAS      B    B     OKLAHOMA    B    B
N TEXAS     B    B     S TEXAS     N    B     W TEXAS     A    B
MINNESOTA   B    A     IOWA        B    A     MISSOURI    B    N
ARKANSAS    B    B     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     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    A    A     FL PENIN    A    A     AK N SLOPE  A    B
AK ALEUTIAN A    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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