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FXUS06 KWBC 282002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST WED JANUARY 28 2015

6-10 DAY OUTLOOK FOR FEB 03 - 07 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 NEAR THE ALEUTIANS/WESTERN ALASKA,
WHILE A RIDGE IS FORECAST OVER THE WESTERN THIRD OF CONUS EXTENDING NORTHWARD
TOWARDS WESTERN CANADA. THE MOST RECENT ECMWF ENSEMBLE MEAN SHOWS SLIGHTLY LESS
ANOMALOUS NORTHERLY FLOW OVER THE NORTH-CENTRAL CONUS COMPARED TO THE LATEST
GFS ENSEMBLE MEAN. RECENT HIGH RESOLUTION RUNS FROM THE GFS AND ECMWF ARE IN
REASONABLY GOOD AGREEMENT WITH THEIR RESPECTIVE ENSEMBLE MEANS, ALTHOUGH
YESTERDAYS 12Z HIGH RESOLUTION ECMWF SOLUTION IS SOMEWHAT LESS PROGRESSIVE WITH
THE MAIN CIRCULATION FEATURES.

THE ENSEMBLE SPAGHETTI CHARTS GENERALLY INDICATE VERY LOW SPREAD OVER THE
EASTERN CONUS, AND MODERATE SPREAD OVER THE WESTERN CONUS. THE PNA INDEX WHICH
RECENTLY HAS BEEN CLOSE TO ZERO IS FORECAST TO BE VERY WEAKLY POSITIVE BY DAY
7, BE POSITIVE BY DAY 10, AND REMAIN POSITIVE THROUGH DAY 14. THE NAO INDEX
WHICH RECENTLY HAS BEEN POSITIVE IS FORECAST TO BE NEAR ZERO BY DAY 7, BE
POSITIVE BY DAY 10, 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, PARTS OF THE NORTHERN AND CENTRAL PLAINS, AND NORTHWESTERN ALASKA,
AND NEAR TO ABOVE NORMAL HEIGHTS OVER THE REMAINDER OF THE CONUS AND ALASKA.

THE TROUGH EXPECTED OVER THE EASTERN U.S. ENHANCES PROBABILITIES FOR BELOW
NORMAL TEMPERATURES FOR MUCH FOR THE CENTRAL AND EASTERN CONUS. CONFIDENCE IS
LOWEST OVER THE NORTHERN PLAINS WHERE SUBTLE DIFFERENCES BETWEEN THE GFS AND
ECMWF ENSEMBLES INTRODUCES LARGE UNCERTAINTY. 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. BELOW NORMAL HEIGHTS ENHANCE
PROBABILITIES FOR BELOW NORMAL TEMPERATURES FOR NORTHERN 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. THE
EXPECTATION OF UPSLOPE FLOW FAVORS ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE
NORTHERN AND CENTRAL ROCKIES. 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 THE ALEUTIANS ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR THE SOUTH COAST OF ALASKA, THE ALASKA PANANDLE, AND COASTAL
SECTIONS OF WASHINGTON. 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 20% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 25% 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, 15% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 5% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND
10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: 6Z GFS ENSEMBLE.

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

8-14 DAY OUTLOOK FOR FEB 05 - 11 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. 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 LATEST HIGH RESOLUTION GFS FORECASTS DEPICT SIGNIFICANTLY MORE
TROUGH ENERGY BEING HELD BACK OVER THE INTERIOR SOUTHWEST AND SOUTHERN PLAINS
AND WERE DISCOUNTED. 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 MOST OF 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
HEIGHTS RISE OVER THE EAST-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 EASTWARD. IN ADDITION, THE
UPSLOPE FLOW OVER THE ROCKIES EXPECTED DURING THE 6-10 DAY PERIOD DIMINISHES
LEADING TO A FORECAST OF NEAR MEDIAN PRECIPITATION FOR THE REGION. JET ENERGY
IS EXPECTED TO APPROACH THE NORTHWEST CONUS. THIS LEADS TO AN EXPANSION OF THE
AREA FORECAST TO HAVE ABOVE MEDIAN PRECIPITATION BUT THIS DEVELOPMENT IS NOT
WELL AGREED UPON BY THE FORECAST TOOLS SO THIS ASPECT OF THE FORECAST IS OF
VERY LOW CONFIDENCE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 20% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 10% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 10% 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 LARGE DISAGREEMENT 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 - 19540202 - 19870207 - 19960211 - 19760119


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:
19540206 - 19540201 - 20050120 - 19840204 - 19760119


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 03 - 07 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    N     OREGON      A    N     NRN CALIF   A    B
SRN CALIF   A    B     IDAHO       A    N     NEVADA      A    B
W MONTANA   A    A     E MONTANA   N    N     WYOMING     A    A
UTAH        A    B     ARIZONA     A    B     COLORADO    A    N
NEW MEXICO  A    B     N DAKOTA    B    B     S DAKOTA    N    B
NEBRASKA    N    B     KANSAS      N    B     OKLAHOMA    B    B
N TEXAS     B    B     S TEXAS     B    B     W TEXAS     B    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    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    N     W VIRGINIA  B    B
MARYLAND    B    B     DELAWARE    B    N     VIRGINIA    B    B
N CAROLINA  B    N     S CAROLINA  B    N     GEORGIA     B    N
FL PNHDL    B    N     FL PENIN    B    A     AK N SLOPE  B    N
AK ALEUTIAN A    N     AK WESTERN  B    N     AK INT BSN  N    N
AK S INT    A    N     AK SO COAST A    A     AK PNHDL    A    A



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 05 - 11 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    N
W MONTANA   A    N     E MONTANA   A    B     WYOMING     A    B
UTAH        A    B     ARIZONA     A    B     COLORADO    A    B
NEW MEXICO  N    B     N DAKOTA    A    B     S DAKOTA    A    B
NEBRASKA    A    B     KANSAS      A    B     OKLAHOMA    N    B
N TEXAS     B    B     S TEXAS     B    B     W TEXAS     N    B
MINNESOTA   N    B     IOWA        N    B     MISSOURI    B    B
ARKANSAS    B    B     LOUISIANA   B    N     WISCONSIN   B    B
ILLINOIS    B    B     MISSISSIPPI B    N     MICHIGAN    B    N
INDIANA     B    B     OHIO        B    N     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    N
AK ALEUTIAN B    N     AK WESTERN  B    N     AK INT BSN  N    N
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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