Prognostic Meteorological Discussion
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FXUS06 KWBC 302002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI JANUARY 30 2015

6-10 DAY OUTLOOK FOR FEB 05 - 09 2015

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN FORECAST OVER NORTH AMERICA. TROUGHS ARE ANTICIPATED OVER
THE EASTERN HALF OF THE CONUS AND MOST OF ALASKA, WHILE A RIDGE IS FORECAST
OVER THE WESTERN HALF OF THE CONUS, EXTENDING NORTHWARD TOWARDS WESTERN CANADA
AND SOUTHEAST ALASKA. THE TIMING DIFFERENCES NOTED AMONG THE ENSEMBLE SOLUTIONS
YESTERDAY DECREASED IN TODAY`S FORECASTS. THE MOST RECENT HIGH RESOLUTION RUNS
FROM THE GFS AND ECMWF ARE A BIT QUICKER TO PROGRESS THE TROUGH FORECAST OVER
THE EASTERN CONUS.

THE IMPROVED AGREEMENT AMONG TODAY`S ENSEMBLE SOLUTIONS IS REFLECTED IN THE
SPAGHETTI DIAGRAMS AS SPREAD AMONG ENSEMBLE MEMBERS IS LOW TO MODERATE ACROSS
MOST OF THE FORECAST DOMAIN. THE PNA INDEX WHICH RECENTLY HAS BEEN NEGATIVE IS
FORECAST TO BE POSITIVE BY DAY 7, AND REMAIN POSITIVE THROUGH DAY 14. THE NAO
INDEX WHICH RECENTLY HAS BEEN POSITIVE IS FORECAST TO DECREASE SLIGHTLY IN
MAGNITUDE BUT REMAIN POSITIVE BY DAY 7, AND REMAIN POSITIVE THROUGH DAY 14.
TODAY`S BLENDED 500-HPA HEIGHT CHART INDICATE NEAR TO BELOW NORMAL HEIGHTS OVER
ROUGHLY THE EASTERN HALF OF THE CONUS, AND ALASKA, AND NEAR TO ABOVE NORMAL
HEIGHTS OVER THE WESTERN HALF OF THE CONUS AND THE WESTERN ALEUTIANS.

THE TROUGH EXPECTED OVER THE EASTERN U.S. ENHANCES PROBABILITIES FOR BELOW
NORMAL TEMPERATURES FOR MUCH FOR THE CENTRAL AND EASTERN CONUS. THE RIDGE AND
AREA OF ABOVE NORMAL HEIGHTS OVER THE WEST TILT THE ODDS TO ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE WESTERN AND WEST-CENTRAL CONUS. BELOW NORMAL
HEIGHTS ENHANCE PROBABILITIES FOR BELOW NORMAL TEMPERATURES FOR NORTHERN AND
CENTRAL ALASKA, WHILE ANOMALOUS SOUTHERLY FLOW FAVORS ABOVE NORMAL TEMPERATURES
FOR SOUTHEASTERN ALASKA AND THE ALASKA PANHANDLE.

THE TROUGH OVER EASTERN NORTH AMERICA ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR FLORIDA. SUBSIDENCE ON THE REAR SIDE OF THE TROUGH FORECAST
OVER THE EAST ENHANCES PROBABILITIES FOR NEAR TO BELOW MEDIAN PRECIPITATION FOR
MUCH OF THE CENTRAL AND EAST-CENTRAL CONUS. ABOVE NORMAL HEIGHTS TILT THE ODDS
TO FAVORING BELOW MEDIAN PRECIPITATION FOR THE SOUTHWEST CONUS. A TROUGH
FORECAST OVER ALASKA AND THE EASTERN PACIFIC ENHANCES PROBABILITIES FOR ABOVE
MEDIAN PRECIPITATION FOR SOUTHEASTERN ALASKA, THE ALASKA PANANDLE, AND THE
NORTHWEST CONUS. HIGH PRESSURE BUILDING NORTHWEST OF ALASKA TILTS THE ODDS TO
BELOW MEDIAN PRECIPITATION FOR PARTS OF NORTHERN AND WESTERN ALASKA.

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


MODEL OF THE DAY: 0Z ECMWF ENSEMBLE.

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

8-14 DAY OUTLOOK FOR FEB 07 - 13 2015

DURING THE WEEK-2 PERIOD, THE ENSEMBLE MEAN SOLUTIONS GENERALLY INDICATE A SLOW
PROGRESSION OF THE CIRCULATION PATTERN FROM THAT FORECAST FOR THE 6-10 DAY
PERIOD AS THE TROUGH FORECAST OVER THE EASTERN CONUS GRADUALLY LIFTS OUT TO THE
NORTHEAST. THE MAIN DIFFERENCE AMONG THE ENSEMBLE MEANS IS IN REGARD TO THE
HANDLING OF THE SOUTHERN PORTION OF THE TROUGH EXPECTED OVER THE EAST. THE
GFS-BASED ENSEMBLES ARE THE QUICKEST TO RAISE HEIGHTS OVER THE SOUTHEAST, THE
ECMWF-BASED ENSEMBLES ARE THE SLOWEST, WHILE THE CANADIAN-BASED ENSEMBLES LIE
IN-BETWEEN. FOR THIS REASON THE CANADIAN ENSEMBLES WERE GIVEN THE HIGHEST
WEIGHT IN TODAY`S WEEK-2 HEIGHT BLEND. A TROUGH IS ANTICIPATED OVER THE EASTERN
CONUS WHILE A RIDGE BUILDS OVER THE WEST. A TROUGH IS FORECAST OVER ALASKA. THE
ENSEMBLE SPAGHETTI CHARTS GENERALLY INDICATE LOW TO MODERATE SPREAD OVER THE
EASTERN CONUS AND MODERATE TO LARGE SPREAD OVER THE CENTRAL AND WESTERN U.S.

TODAY`S WEEK-2 BLEND CHART INDICATES NEAR TO BELOW NORMAL HEIGHTS OVER THE
EASTERN THIRD OF THE CONUS AND ALASKA, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE
ANTICIPATED OVER THE WESTERN TWO THIRDS OF THE CONUS AND THE WESTERN ALEUTIANS.

THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK-2 ARE
MOSTLY SIMILAR TO THOSE EXPECTED DURING THE 6-10 DAY PERIOD. ALTHOUGH, AS THE
EASTERN TROUGH LIFTS OUT TO THE NORTHEAST, THE AREA OF EXPECTED BELOW NORMAL
TEMPERATURES OVER THE CENTRAL CONUS DEPICTED FOR THE 6-10 DAY PERIOD SHRINKS A
BIT AS THE AREA OF ABOVE NORMAL TEMPERATURES EXPANDS EASTWARD. AS THE TROUGH
ANTICIPATED OVER THE EASTERN CONUS PROGRESSES TO THE NORTHEAST, THE FORECAST
AREA OF ABOVE MEDIAN PRECIPITATION OVER FLORIDA DURING THE 6-10 DAY PERIOD IS
EXPECTED TO TRANSITION TO NEAR MEDIAN PRECIPITATION FOR WEEK-2.

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,
10% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 15% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 25% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 20% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED
ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO FAIR AGREEMENT AMONG THE MODELS AND THE DIFFICULTIES IN TIMING ASSOCIATED
WITH A PROGRESSIVE 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
FEBRUARY 19

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:
20050118 - 19760119 - 19540207 - 20050131 - 20090119


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:
20050118 - 20050129 - 19540207 - 20030131 - 20030126


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 05 - 09 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 07 - 13 2015

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

                           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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