Prognostic Meteorological Discussion
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FXUS06 KWBC 212009
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI NOVEMBER 21 2014

6-10 DAY OUTLOOK FOR NOV 27 - DEC 01, 2014

TODAY`S MODELS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA CIRCULATION PATTERN
FORECAST OVER NORTH AMERICA. MOST OF TODAY`S MODELS PREDICT A TROUGH NEAR THE
EAST COAST, AND ANOMALOUS RIDGING IN THE WESTERN HALF OF THE CONUS. TODAY`S 0Z
ECMWF ENSEMBLE INDICATES A MORE AMPLIFIED PATTERN, BUT HAS ALSO SHOWN LESS
RUN-TO-RUN CONSISTENCY IN THE RECENT PAST THAN THE GFS ENSEMBLE. THEREFORE
TODAY`S 0Z GFS ENSEMBLE WAS FAVORED IN TODAY`S MANUAL 500-HPA HEIGHT BLEND.

ABOVE NORMAL HEIGHTS OVER ALASKA INCREASE THE CHANCES FOR ABOVE NORMAL
TEMPERATURES THROUGHOUT MOST OF THE STATE. ANOMALOUS RIDGING ALSO INCREASES THE
LIKELIHOOD OF ABOVE NORMAL TEMPERATURES IN THE WESTERN CONUS. BELOW NORMAL
TEMPERATURES ARE FAVORED OVER MUCH OF THE REMAINDER OF THE CONUS DUE TO
ANOMALOUS NORTHERLY FLOW AND BELOW NORMAL 500-HPA HEIGHTS.

IN ALASKA, TODAY`S PRECIPITATION TOOLS INDICATE LESS PRECIPITATION THAN
YESTERDAY`S TOOLS, AS THE MODELS ARE NOW FORECASTING MORE INFLUENCE FROM
SURFACE HIGH PRESSURE AND MORE ANOMALOUS RIDGING. THIS FAVORS NEAR MEDIAN
PRECIPITATION FOR MUCH OF THE STATE, WITH BELOW MEDIAN PRECIPITATION FAVORED
FOR THE ALEUTIANS. SOME STORM SYSTEM ACTIVITY FORECAST TO MOVE ACROSS THE
NORTHERN TIER INCREASES THE LIKELIHOOD OF ABOVE MEDIAN PRECIPITATION FOR PARTS
OF THE NORTHERN PLAINS INTO THE GREAT LAKES. ELSEWHERE, ANOMALOUS SURFACE HIGH
PRESSURE DOMINATES, ENHANCING THE LIKELIHOOD OF BELOW MEDIAN PRECIPITATION.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 40% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 30% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 15% OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8


MODEL OF THE DAY: 0Z GEFS MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT, A FAIRLY AMPLIFIED PATTERN, AND FAIRLY GOOD AGREEMENT
AMONG THE TOOLS.

8-14 DAY OUTLOOK FOR NOV 29 - DEC 05, 2014

BY THE WEEK-2 PERIOD, THE 500-HPA PATTERN IS EXPECTED TO BE SHIFTED EASTWARD
FROM THAT FORECAST FOR THE 6-10 DAY PERIOD, AND BECOME LESS CERTAIN. THOUGH
TODAY`S MODELS ARE IN BETTER AGREEMENT THAN YESTERDAY, SOME OF THE TEMPERATURE
AND PRECIPITATION TOOLS ARE STILL IN POOR AGREEMENT, KEEPING FORECAST
PROBABILITIES RELATIVELY LOW, EVEN FOR WEEK-2.

AS A MORE ZONAL FLOW IS ANTICIPATED OVER THE EASTERN U.S., BELOW NORMAL
TEMPERATURES ARE NO LONGER FAVORED, EXCEPT NEAR THE GREAT LAKES, WHERE BELOW
NORMAL HEIGHTS ARE EXPECTED TO TAKE THE LONGEST TO RETREAT NORTH INTO CANADA.
ANOMALOUS TROUGHING IS FORECAST BY SEVERAL OF TODAY`S MODELS TO ARRIVE NEAR THE
WEST COAST, BRING SEVERAL STORM SYSTEMS ONSHORE, ENHANCING THE CHANCES FOR
ABOVE MEDIAN PRECIPITATION FOR PARTS OF THE PACIFIC NORTHWEST, CALIFORNIA, AND
THE GREAT BASIN. SOME RESURGENCE OF STORM SYSTEM ACTIVITY IS FORECAST FROM THE
MISSISSIPPI VALLEY INTO THE EASTERN CONUS, FAVORING NEAR MEDIAN PRECIPITATION
THERE, UNLIKE THE BELOW MEDIAN PRECIPITATION FAVORED IN THE 6-10 DAY PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 60% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, AND 40% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED
ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO FAIRLY AGREEMENT AMONG THE MODELS, AS WELL AS WEAKER ANOMALIES, AND FAIRLY
POOR AGREEMENT AMONG THE TOOLS.

FORECASTER: MIKE CHARLES

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 18

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:
20001119 - 19921114 - 19511101 - 19601108 - 20021102


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:
20001118 - 20021103 - 19511031 - 19921115 - 19601104


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 27 - DEC 01, 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR NOV 29 - DEC 05, 2014

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

                           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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