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FXUS06 KWBC 292002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST THU JANUARY 29 2015

6-10 DAY OUTLOOK FOR FEB 04 - 08 2015

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN FORECAST OVER NORTH AMERICA. TROUGHS ARE ANTICIPATED OVER
THE EASTERN TWO-THIRDS OF THE CONUS AND WESTERN ALASKA, WHILE A RIDGE IS
FORECAST OVER THE WESTERN THIRD OF CONUS EXTENDING NORTHWARD TOWARDS WESTERN
CANADA. THE GFS-BASED ENSEMBLES DEPICT THE MAIN CIRCULATION FEATURES A BIT
FURTHER EAST COMPARED TO THE ECMWF AND CANADIAN ENSEMBLES. RECENT HIGH
RESOLUTION RUNS FROM THE ECMWF ARE IN REASONABLY GOOD AGREEMENT WITH THEIR
RESPECTIVE ENSEMBLE MEANS. THE LATEST GFS HIGH RESOLUTION SOLUTIONS ARE A BIT
LESS PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES COMPARED TO THEIR
RESPECTIVE ENSEMBLE MEANS. SINCE THE ECMWF-BASED SOLUTIONS ARE MORE CONSISTENT,
THEY WERE FAVORED IN TODAYS MANUAL 500-HPA BLEND CHART.

THE ENSEMBLE SPAGHETTI CHARTS GENERALLY INDICATE VERY LOW SPREAD OVER THE
EASTERN CONUS, AND LOW TO MODERATE MODERATE SPREAD OVER THE WESTERN CONUS. 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 IN MAGNITUDE BUT REMAIN POSITIVE BY DAY 7, AND
REMAIN POSITIVE THROUGH DAY 14. TODAY`S BLENDED 500-HPA HEIGHT CHART INDICATES
NEAR TO BELOW NORMAL HEIGHTS OVER 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 THIRD OF THE CONUS AND PARTS OF THE
CENTRAL ROCKIES AND CENTRAL PLAINS. BELOW NORMAL HEIGHTS ENHANCE PROBABILITIES
FOR BELOW NORMAL TEMPERATURES FOR NORTHERN AND WESTERN ALASKA, WHILE ANOMALOUS
SOUTHEASTERLY FLOW FAVORS ABOVE NORMAL TEMPERATURES FOR SOUTHERN ALASKA AND THE
ALASKA PANHANDLE.

THE TROUGH OVER EASTERN NORTH AMERICA ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR FLORIDA AND COASTAL SECTIONS OF THE SOUTHEAST. SUBSIDENCE ON
THE REAR SIDE OF THE TROUGH FORECAST OVER THE EAST ENHANCES PROBABILITIES FOR
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 NEAR WESTERN ALASKA ENHANCES
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR EASTERN ALASKA, THE ALASKA
PANANDLE, AND SECTIONS OF WASHINGTON, OREGON, AND EXTREME NORTHWESTERN
CALIFORNIA. HIGH PRESSURE BUILDING NORTHWEST OF ALASKA TILTS THE ODDS TO BELOW
MEDIAN PRECIPITATION FOR PARTS OF NORTHWESTERN ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5% OF TODAY`S OPERATIONAL 0Z GFS
CENTERED ON DAY 8, 35% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
20% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 15% OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 15% 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 06 - 12 2015

DURING THE WEEK-2 PERIOD, THE ENSEMBLE MEAN SOLUTIONS GENERALLY INDICATE A
PROGRESSION OF THE CIRCULATION PATTERN FROM THAT FORECAST FOR THE 6-10 DAY
PERIOD AS HEIGHTS RISE OVER THE NORTH-CENTRAL CONUS. THE GFS-BASED ENSEMBLE
SOLUTIONS CONTINUE TO BE MORE PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES
COMPARED TO THE ECMWF AND CANADIAN ENSEMBLES. THE 0Z HIGH RESOLUTION GFS
FORECAST IS LESS PROGRESSIVE THAN ITS CORRESPONDING ENSEMBLE MEAN. SO AS WAS
TRUE FOR THE 6-10 DAY PERIOD, THE WEEK-2 BLEND IS MORE HEAVILY WEIGHTED BY THE
ECMWF AND CANADIAN FORECASTS. A TROUGH IS ANTICIPATED OVER THE EASTERN CONUS
WHILE A RIDGE BUILDS OVER THE WEST. A TROUGH IS FORECAST OVER WESTERN ALASKA
WHILE A RIDGE IS EXPECTED OVER THE EASTERN PART OF THE STATE. THE ENSEMBLE
SPAGHETTI CHARTS GENERALLY INDICATE LOW TO MODERATE SPREAD OVER THE EASTERN
CONUS AND LARGE SPREAD OVER THE WEST.

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 ALASKA PANHANDLE.

THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK-2 ARE
MOSTLY SIMILAR TO THOSE EXPECTED DURING THE 6-10 DAY PERIOD. ALTHOUGH, AS
HEIGHTS RISE OVER THE NORTH-CENTRAL CONUS, 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 EAST/NORTHEASTWARD. JET
ENERGY IS EXPECTED TO APPROACH THE NORTHWEST CONUS. THIS LEADS TO AN EXPANSION
OF THE AREA FORECAST TO HAVE ABOVE MEDIAN PRECIPITATION. AS THE TROUGH
ANTICIPATED OVER THE EASTERN CONUS PROGRESSES TO THE NORTHEAST, THE FORECAST
AREA OF ABOVE MEDIAN PRECIPITATION ALONG THE SOUTHEAST COAST AND 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 OPERATIONAL 0Z
GFS CENTERED ON DAY 11, 50% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, 20% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, 15%
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 5% 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 FAIRLY GOOD AGREEMENT AMONG THE MODELS OFFSET BY THE DIFFICULTIES IN TIMING
ASSOCIATED WITH A PROGRESSIVE CIRCULATION PATTERN AND RELATIVELY POOR AGREEMENT
AMONG THE PRECIPITATION FORECAST TOOLS.

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:
19540207 - 20050119 - 19760119 - 20050130 - 19870208


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:
19540207 - 20050120 - 20050129 - 19910209 - 19870209


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 04 - 08 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 06 - 12 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    N     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    N     N DAKOTA    A    B     S DAKOTA    A    B
NEBRASKA    A    B     KANSAS      A    B     OKLAHOMA    N    B
N TEXAS     N    B     S TEXAS     N    B     W TEXAS     N    N
MINNESOTA   A    B     IOWA        A    B     MISSOURI    N    B
ARKANSAS    N    B     LOUISIANA   B    B     WISCONSIN   N    N
ILLINOIS    N    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    B
VERMONT     B    B     NEW HAMP    B    B     MAINE       B    N
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    N     S CAROLINA  B    N     GEORGIA     B    B
FL PNHDL    B    B     FL PENIN    B    N     AK N SLOPE  N    N
AK ALEUTIAN N    N     AK WESTERN  N    N     AK INT BSN  N    A
AK S INT    A    A     AK SO COAST A    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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