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FXUS06 KWBC 092038
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 09 2016

6-10 DAY OUTLOOK FOR DEC 15 - 19 2016

TODAY`S MODELS EXHIBIT FAIR AGREEMENT ON THE PREDICTED 500-HPA HEIGHT PATTERN.
A STRONG RIDGE IS PREDICTED OVER ALASKA. DOWNSTREAM OF THIS RIDGE, CYCLONIC
FLOW AND BELOW TO MUCH BELOW NORMAL HEIGHTS ARE PREDICTED ACROSS THE WESTERN
AND NORTHERN CONUS. WEAK RIDGING AND ABOVE NORMAL HEIGHTS ARE FORECAST FARTHER
TO THE SOUTH OVER PARTS OF THE SOUTHEASTERN CONUS. ENSEMBLE SPREAD IS
MODERATELY HIGH OVER THE WESTERN CONUS, WHERE HEIGHTS ARE GENERALLY PREDICTED
BY TODAY`S MODELS TO BE LOWER RELATIVE TO YESTERDAY`S MODEL SOLUTIONS. ENSEMBLE
SPREAD IS ALSO MODERATE TO HIGH OVER ALASKA IN ASSOCIATION WITH THE RIDGE
PREDICTED OVER THE STATE. THE GREATEST WEIGHT IN TODAY`S MANUAL, 500-HPA HEIGHT
BLEND WAS GIVEN TO THE 0Z ECMWF ENSEMBLE MEAN SOLUTION BASED ON CONSIDERATIONS
OF RECENT SKILL AND ON ANALOG CORRELATIONS, WHICH MEASURE HOW CLOSELY THE
PREDICTED PATTERN MATCHES CASES THAT HAVE OCCURRED IN THE PAST.

BELOW NORMAL TEMPERATURES ARE STRONGLY FAVORED ACROSS THE NORTHERN TIER OF THE
CONUS AS WELL AS MUCH OF THE CENTRAL AND WESTERN CONUS UNDERNEATH PREDICTED
CYCLONIC FLOW AND BELOW NORMAL HEIGHTS. HOWEVER, ENHANCED PROBABILITIES FOR
ABOVE NORMAL TEMPERATURES ARE INDICATED FOR PARTS OF THE SOUTHWEST AS DYNAMICAL
MODEL GUIDANCE FAVORS WARMER THAN NORMAL CONDITIONS EARLY IN THE PERIOD.
PREDICTED ABOVE NORMAL HEIGHTS LEAD TO ENHANCED PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES FOR PARTS OF THE SOUTHEASTERN CONUS. ANOMALOUS NORTHERLY FLOW
AHEAD OF THE RIDGE PREDICTED OVER CENTRAL ALASKA FAVORS BELOW NORMAL
TEMPERATURES FOR THE PANHANDLE. ABOVE NORMAL TEMPERATURES ARE FAVORED NEAR AND
BEHIND THE PREDICTED RIDGE AXIS FOR THE ALEUTIANS AS WELL AS WESTERN AND
NORTHERN MAINLAND ALASKA.

THE RIDGE PREDICTED OVER ALASKA FAVORS A DRY PATTERN FOR THE PANHANDLE AND
PARTS OF THE SOUTH COAST. PREDICTED SOUTHWESTERLY LOW LEVEL FLOW AROUND THE
ASSOCIATED SURFACE HIGH FAVORS ABOVE MEDIAN PRECIPITATION FOR NORTHWESTERN
ALASKA. TELECONNECTIONS FROM THE PREDICTED 500-HPA POSITIVE HEIGHT ANOMALY
CENTER OVER THE WESTERN GULF OF ALASKA FAVORS BELOW MEDIAN PRECIPITATION
DOWNSTREAM OVER THE PACIFIC NORTHWEST. THERE ARE ENHANCED PROBABILITIES FOR
ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE REMAINDER OF THE WESTERN CONUS IN
ASSOCIATION WITH A PREDICTED MEAN TROUGH. ENHANCED PROBABILITIES FOR ABOVE
MEDIAN PRECIPITATION ARE ALSO INDICATED FOR MUCH OF THE EASTERN CONUS DUE TO AN
ENHANCED TEMPERATURE GRADIENT ASSOCIATED WITH PREDICTED ABOVE NORMAL HEIGHTS
OVER THE SOUTHEAST AND FORECAST BELOW NORMAL HEIGHTS FARTHER TO THE NORTH AND
WEST. BELOW MEDIAN PRECIPITATION IS FAVORED FOR PARTS OF THE SOUTHERN HIGH
PLAINS CONSISTENT WITH BOTH DYNAMICAL MODEL GUIDANCE AND ANALOGS FROM THE
MANUAL BLEND.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 5% OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8, 35% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY
8, 5% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, AND 10% 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.

8-14 DAY OUTLOOK FOR DEC 17 - 23 2016

DURING THE 8-14 DAY PERIOD, THE ENSEMBLE MEAN SOLUTIONS HAVE COME IN TO BETTER
AGREEMENT RELATIVE TO YESTERDAY`S MODEL SUITE. A STRONG RIDGE IS FORECAST OVER
ALASKA. DOWNSTREAM OF THIS RIDGE, CYCLONIC FLOW AND BELOW NORMAL HEIGHTS ARE
GENERALLY FORECAST OVER THE WESTERN AND NORTHERN CONUS. FARTHER TO THE SOUTH,
RIDGING AND ABOVE NORMAL HEIGHTS ARE FORECAST OVER MUCH OF THE SOUTHEASTERN
CONUS. ENSEMBLE SPREAD IS MODERATE OVER THE CONUS AND HIGH OVER ALASKA. THE
OFFICIAL 500-HPA HEIGHT FORECAST REPRESENTS A BLEND OF THE GFS AND ECMWF BASED
SOLUTIONS.

THERE ARE ENHANCED PROBABILITIES FOR BELOW NORMAL TEMPERATURES FOR MUCH OF THE
NORTHERN, WESTERN, AND CENTRAL CONUS UNDERNEATH PREDICTED CYCLONIC FLOW.
HOWEVER, ABOVE NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE SOUTHWEST
CONSISTENT WITH GEFS REFORECAST GUIDANCE AND BIAS CORRECTED TEMPERATURES FROM
THE 0Z ECMWF ENSEMBLE MEMBERS. THERE ARE ENHANCED PROBABILITIES FOR ABOVE
NORMAL TEMPERATURES THE SOUTHEASTERN CONUS DUE TO PREDICTED RIDGING AND ABOVE
NORMAL HEIGHTS. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR WESTERN AND NORTHERN
ALASKA IN ASSOCIATION WITH PREDICTED RIDGING AND ABOVE NORMAL HEIGHTS. THERE
ARE ENHANCED PROBABILITIES FOR BELOW NORMAL TEMPERATURES AHEAD OF THE RIDGE FOR
THE PANHANDLE UNDERNEATH PREDICTED ANOMALOUS, NORTHERLY 500-HPA FLOW.

ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE SOUTHWESTERN CONUS, GREAT
BASIN, AND ROCKIES UNDERNEATH PREDICTED CYCLONIC FLOW. ENHANCED PROBABILITIES
FOR ABOVE MEDIAN PRECIPITATION ARE ALSO INDICATED FOR THE EASTERN CONUS DUE TO
AN ANTICIPATED ENHANCED TEMPERATURE GRADIENT BETWEEN THE RIDGE FORECAST OVER
THE SOUTHEASTERN CONUS AND THE TROUGH PREDICTED OVER THE WEST. BELOW MEDIAN
PRECIPITATION IS FAVORED FOR THE FLORIDA PENINSULA DUE TO PREDICTED RIDGING AND
ABOVE NORMAL HEIGHTS. BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE PACIFIC
NORTHWEST, THE ALASKA PANHANDLE, AND PARTS OF THE SOUTH COAST UNDERNEATH
PREDICTED ANOMALOUS, NORTHERLY FLOW AHEAD OF A RIDGE FORECAST OVER THE GULF OF
ALASKA. ABOVE MEDIAN PRECIPITATION IS FAVORED FOR NORTHWESTERN ALASKA IN
ASSOCIATION WITH ANOMALOUS SOUTHWESTERLY 500-HPA BEHIND THE RIDGE AXIS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 30% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, 20% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 5% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED
ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO
RELATIVE GOOD ENSEMBLE MEAN AGREEMENT OFFSET BY MODERATELY HIGH SPREAD AMONG
THE COMPONENT ENSEMBLE MEMBERS.

FORECASTER: SCOTT HANDEL

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:
19961220 - 19681221 - 20051129 - 19731127 - 19661202


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:
19961219 - 20051202 - 19681221 - 19551216 - 19661130


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 15 - 19 2016

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    B     OREGON      B    N     NRN CALIF   B    A
SRN CALIF   N    A     IDAHO       B    A     NEVADA      B    A
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    A
UTAH        B    A     ARIZONA     A    A     COLORADO    B    A
NEW MEXICO  A    N     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    B    N
N TEXAS     B    A     S TEXAS     N    N     W TEXAS     B    B
MINNESOTA   B    A     IOWA        B    A     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   N    A     WISCONSIN   B    A
ILLINOIS    B    A     MISSISSIPPI N    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    N     FL PENIN    A    B     AK N SLOPE  A    A
AK ALEUTIAN A    N     AK WESTERN  A    A     AK INT BSN  A    N
AK S INT    N    B     AK SO COAST N    B     AK PNHDL    B    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 17 - 23 2016

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