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FXUS06 KWBC 262000
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 26 2014

6-10 DAY OUTLOOK FOR JAN 01 - 05 2015

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE EXPECTED
500-HPA HEIGHT PATTERN FOR THE 6-10 DAY PERIOD OVER NORTH AMERICA. TROUGHS ARE
ANTICIPATED NEAR HUDSON BAY AND OVER THE INTERIOR SOUTHWEST CONUS, WHILE A
RIDGE IS EXPECTED OVER THE EASTERN PACIFIC EXTENDING NORTHWESTWARD TO ALASKA.
SOME MINOR TIMING DIFFERENCES ARE APPARENT WITH RESPECT TO THE PROGRESSION OF
THE TROUGH FORECAST OVER THE INTERIOR SOUTHWEST CONUS, WITH THE GFS-BASED
SOLUTIONS BEING SLIGHTLY MORE PROGRESSIVE COMPARED TO THE ECMWF AND CANADIAN
ENSEMBLE MEANS. RECENT HIGH RESOLUTION SOLUTIONS FROM THE GFS AND ECMWF ARE IN
REASONABLY GOOD AGREEMENT WITH THEIR RESPECTIVE ENSEMBLE MEANS.

THE ENSEMBLE SPAGHETTI CHARTS INDICATE RELATIVELY LOW SPREAD OVER THE CENTRAL
AND EASTERN CONUS, AND MODERATE TO LARGE SPREAD OVER THE WESTERN CONUS AND
EASTERN PACIFIC. THE PNA INDEX WHICH RECENTLY HAS BEEN CLOSE TO ZERO IS
EXPECTED TO BE POSITIVE BY DAY 7, NEAR ZERO AT DAY 10, AND REMAIN NEAR ZERO AT
DAY 14. THE AO INDEX WHICH RECENTLY HAS BEEN CLOSE TO ZERO IS FORECAST TO
BECOME STRONGLY POSITIVE BY DAY 7, REMAIN POSITIVE BY DAY 10, AND BE CLOSE TO
ZERO BY DAY 14. THE SPREAD AMONG THE ENSEMBLE MEMBERS FOR THE AO INDEX IS
RELATIVELY LARGE THROUGH THE PERIOD. TODAY`S 500-HPA BLEND CHART INDICATES NEAR
TO ABOVE NORMAL HEIGHTS OVER THE SOUTHEASTERN AND NORTHWESTERN CONUS, AND
ALASKA, AND NEAR TO BELOW NORMAL HEIGHTS OVER THE REMAINDER OF THE CONUS.

ANOMALOUS NORTHERLY FLOW AND/OR BELOW NORMAL HEIGHTS ENHANCE PROBABILITIES FOR
BELOW NORMAL TEMPERATURES FOR MOST OF THE CONUS. THE MAIN EXCEPTION IS OVER THE
SOUTHEAST WHERE NEAR TO ABOVE NORMAL HEIGHTS FAVORS ABOVE NORMAL TEMPERATURES.
ABOVE NORMAL HEIGHTS TILT THE ODDS TO ABOVE NORMAL TEMPERATURES FOR MOST OF
ALASKA.

ANOMALOUS SOUTHWESTERLY FLOW ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE SOUTHEASTERN CONUS, APPALACHIANS, AND COASTAL
SECTIONS OF THE MID-ATLANTIC. SHORTWAVES ON THE REAR SIDE OF THE TROUGH
FORECAST NEAR HUDSON BAY TILT THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR PARTS
OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. ANOMALOUS SOUTHERLY FLOW
ENHANCES PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR PARTS OF NORTHWESTERN
ALASKA. ABOVE NORMAL HEIGHTS AND ANOMALOUS NORTH/NORTHEASTERLY FLOW TILT THE
ODDS TO BELOW MEDIAN PRECIPITATION FOR PARTS OF THE NORTHWESTERN CONUS AND THE
ALASKA PANHANDLE. SINKING MOTION ON THE REAR SIDE OF THE TROUGH FORECAST NEAR
HUDSON BAY ENHANCES PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR PARTS OF
THE CENTRAL CONUS.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 25% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 5% OF YESTERDAY`S OPERATIONAL 12Z ECMWF CENTERED ON DAY 7,
AND 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: YESTERDAY`S 12Z ECMWF ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG THE ENSEMBLE MEAN FORECASTS AND MOST OF THE FORECAST
TOOLS.

8-14 DAY OUTLOOK FOR JAN 03 - 09 2015

THE ENSEMBLE MEAN SOLUTIONS INDICATE THAT THE WEEK 2 CIRCULATION PATTERN IS
EXPECTED TO BE DEAMPLIFIED AND SOMEWHAT PROGRESSIVE FROM THAT FORECAST FOR THE
6-10 DAY PERIOD. HEIGHTS ARE ANTICIPATED TO RISE OVER THE SOUTHWEST AND EASTERN
CONUS. A TROUGH IS EXPECTED TO PERSIST NORTHEAST OF HUDSON`S BAY, WHILE A RIDGE
IS FORECAST TO APPROACH THE WEST COAST AND EXTEND NORTHWESTWARD TO ALASKA. THE
GFS-BASED SOLUTIONS REMAIN SOMEWHAT MORE PROGRESSIVE WITH THE CIRCULATION
FEATURES OVER THE EASTERN PACIFIC/SOUTHWEST CONUS. RECENT HIGH RESOLUTION RUNS
OF THE GFS ARE GENERALLY IN FAIRLY GOOD AGREEMENT WITH THEIR RESPECTIVE
ENSEMBLE MEANS ALTHOUGH AMPLITUDE DIFFERENCES ARE APPARENT FOR SOME OF THE
INDIVIDUAL CIRCULATION FEATURES. THE ENSEMBLE SPAGHETTI DIAGRAMS GENERALLY
INDICATE LOW TO MODERATE SPREAD OVER THE EASTERN CONUS, AND MODERATE TO LARGE
SPREAD OVER THE WESTERN CONUS AND EASTERN PACIFIC.

TODAY`S WEEK 2 BLEND CHART INDICATES NEAR TO BELOW NORMAL HEIGHTS OVER PARTS OF
THE NORTHERN INTERMOUNTAIN WEST, CENTRAL GREAT BASIN, NORTHERN AND CENTRAL
ROCKIES, THE NORTHERN AND CENTRAL PLAINS, AND THE UPPER MISSISSIPPI VALLEY, AND
NEAR TO ABOVE NORMAL HEIGHTS OVER THE REMAINDER OF THE CONUS AND ALASKA.

AS HEIGHTS RISE OVER THE SOUTHWESTERN AND EASTERN CONUS, AN EXPANSION OF THE
THE AREA OF ABOVE NORMAL TEMPERATURES IS FORECAST FOR PARTS OF THE EASTERN
CONUS, WHILE A PORTION OF THE WEST COAST IS FAVORED TO TRANSITION FROM BELOW
NORMAL TEMPERATURES DURING THE 6-10 DAY PERIOD, TO ABOVE NORMAL TEMPERATURES
DURING WEEK 2. OTHERWISE, THE EXPECTED TEMPERATURE ANOMALY PATTERNS FOR WEEK 2
ARE LITTLE CHANGED FROM THOSE PREDICTED FOR THE 6-10 DAY PERIOD.

ANOMALOUS SOUTHWESTERLY FLOW ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE EASTERN CONUS, WHILE ANOMALOUS SOUTHEASTERLY FLOW
TILT THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR PARTS OF NORTHWESTERN ALASKA
AND THE ALEUTIANS. ANOMALOUS NORTHERLY FLOW ELEVATES THE CHANCES FOR BELOW
MEDIAN PRECIPITATION FOR PARTS OF THE ALASKA PANHANDLE. RISING HEIGHTS ENHANCE
PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHWESTERN AND
WEST-CENTRAL CONUS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 5% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11,
5% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 30% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 25% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, AND 25% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO FAIRLY GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS OFFSET BY THE
DIFFICULTY OF FORECASTING A DEAMPLIFYING CIRCULATION PATTERN.

FORECASTER: RANDY SCHECHTER

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
JANUARY 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:
19991209 - 20070106 - 19581231 - 19921214 - 20031228


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:
19991211 - 20070108 - 19991206 - 19921214 - 19711208


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 01 - 05 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 03 - 09 2015

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