Prognostic Meteorological Discussion
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FXUS06 KWBC 272001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST MON FEBRUARY 27 2017

6-10 DAY OUTLOOK FOR MAR 05 - 09 2017

TODAY`S DYNAMICAL MODELS ARE IN FAIR AGREEMENT ON THE 500-HPA FLOW PATTERN OVER
THE FORECAST DOMAIN. AN AMPLIFIED PATTERN IS PREDICTED OVER ALASKA AS A STRONG
RIDGE IS FORECAST OVER THE WESTERN ALEUTIANS AND A DEEP TROUGH IS PREDICTED TO
DOMINATE MUCH OF THE REMAINDER OF THE STATE. A LOWER AMPLITUDE PATTERN IS
FORECAST FARTHER TO THE SOUTH OVER THE CONUS. RIDGING AND ABOVE NORMAL HEIGHTS
ARE FORECAST OVER THE SOUTHWESTERN AND SOUTH-CENTRAL CONUS WHILE A RELATIVELY
LOW AMPLITUDE TROUGH IS FORECAST FARTHER TO THE EAST OVER THE NORTHEASTERN
CONUS. ENSEMBLE SPREAD IS RELATIVELY HIGH OVER MUCH OF THE CONUS INDICATING
THAT THERE ARE SIGNIFICANT DIFFERENCES AMONG INDIVIDUAL ENSEMBLE MEMBERS IN
RESOLVING SHORTWAVE FEATURES OVER MUCH OF THE COUNTRY. DUE, IN PART, TO THESE
DIFFERENCES, THE ENSEMBLE MEAN SOLUTIONS WERE GIVEN THE MAJORITY OF THE WEIGHT
IN TODAY`S 500-HPA MANUAL HEIGHT BLEND. THE GREATEST WEIGHT WAS GIVEN TO
TODAY`S 0Z CANADIAN ENSEMBLE MEAN AS IT HAD THE HIGHEST ANALOG CORRELATION
(WHICH MEASURES HOW CLOSELY THE FORECAST PATTERN MATCHES CASES THAT HAVE
OCCURRED IN THE PAST) AMONG TODAY`S ENSEMBLE MEAN SOLUTIONS.

BELOW NORMAL TEMPERATURES ARE STRONGLY FAVORED FOR MUCH OF ALASKA DUE TO THE
DEEP TROUGH PREDICTED TO DOMINATE THE STATE. ENHANCED PROBABILITIES FOR BELOW
NORMAL TEMPERATURES ARE ALSO INDICATED FOR THE NORTHWESTERN CONUS CONSISTENT
WITH BIAS-CORRECTED DYNAMICAL MODEL GUIDANCE FROM THE GEFS, ECMWF, AND CANADIAN
ENSEMBLES. CONVERSELY, RIDGING AND NEAR TO ABOVE NORMAL HEIGHTS FAVOR ABOVE
NORMAL TEMPERATURES FOR THE SOUTHWESTERN AND CENTRAL CONUS. ABOVE NORMAL
TEMPERATURES ARE ALSO FAVORED FOR MUCH OF THE EASTERN CONUS (ALTHOUGH WITH
LOWER PROBABILITIES) DUE TO ANTICIPATED MILDER THAN NORMAL AIR EARLY IN THE
PERIOD.

BELOW MEDIAN PRECIPITATION IS FAVORED FOR CENTRAL AND WESTERN ALASKA DUE TO THE
STRONG TROUGH AND ASSOCIATED ANOMALOUS NORTHERLY MID LEVEL FLOW PREDICTED OVER
THE STATE. ABOVE MEDIAN PRECIPITATION IS FAVORED FOR THE PANHANDLE DOWNSTREAM
OF THE PREDICTED TROUGH AXIS. THERE ARE INCREASED PROBABILITIES FOR ABOVE
MEDIAN PRECIPITATION FOR THE NORTHWESTERN CONUS DUE TO THE POTENTIAL FOR
ENHANCED PACIFIC FLOW. BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE
SOUTHWESTERN CONUS AND MUCH OF THE CENTRAL CONUS DUE TO PREDICTED RIDGING AND
NEAR TO ABOVE NORMAL HEIGHTS. ABOVE MEDIAN PRECIPITATION IS WEAKLY FAVORED FOR
THE GREAT LAKES REGION AND PARTS OF THE NORTHEAST IN ASSOCIATION WITH A
PREDICTED TROUGH. ABOVE MEDIAN PRECIPITATION IS ALSO FAVORED FOR PORTIONS OF
THE FLORIDA PENINSULA AND GULF COAST REGION UNDERNEATH PREDICTED MEAN EASTERLY
LOW LEVEL FLOW.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 10% OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8, 15% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY
8, 10% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 30% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 5% OF YESTERDAY`S 12Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 7


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: BELOW AVERAGE, 2 OUT OF 5, DUE TO
MODERATELY HIGH ENSEMBLE SPREAD OVER MUCH OF THE CONUS.

8-14 DAY OUTLOOK FOR MAR 07 - 13 2017

DURING THE WEEK-2 PERIOD, AN AMPLIFIED 500-HPA FLOW PATTERN CONTINUES TO BE
FORECAST FOR ALASKA. A RIDGE IS PREDICTED OVER THE WESTERN ALEUTIANS WHILE A
STRONG TROUGH IS FORECAST DOWNSTREAM OVER CENTRAL, MAINLAND ALASKA. RIDGING AND
ABOVE NORMAL HEIGHTS ARE FORECAST OVER MUCH OF THE WESTERN CONUS WHILE A TROUGH
IS PREDICTED OVER THE NORTHEAST. ENSEMBLE SPREAD IS MODERATELY HIGH OVER MUCH
OF THE FORECAST DOMAIN. AS A RESULT, THE OFFICIAL 500-HPA HEIGHT BLEND FOR THE
WEEK-2 PERIOD IS BASED PRIMARILY ON THE ENSEMBLE MEAN SOLUTIONS.

BELOW NORMAL TEMPERATURES ARE STRONGLY FAVORED FOR MOST OF ALASKA DUE TO THE
DEEP TROUGH PREDICTED OVER THE STATE. THERE ARE ENHANCED PROBABILITIES FOR
ABOVE NORMAL TEMPERATURES FOR THE SOUTHWESTERN AND CENTRAL CONUS DUE TO
PREDICTED RIDGING AND NEAR TO ABOVE NORMAL HEIGHTS. BELOW NORMAL TEMPERATURES
ARE FAVORED FOR THE NORTHEASTERN CONUS DUE TO A PREDICTED MEAN TROUGH. ENHANCED
PROBABILITIES FOR BELOW NORMAL TEMPERATURES ARE ALSO INDICATED FOR PARTS OF THE
NORTHWESTERN CONUS CONSISTENT WITH BIAS CORRECTED DYNAMICAL MODEL GUIDANCE.

BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE SOUTHWESTERN CONUS EXTENDING TO
MUCH OF THE CENTRAL CONUS DUE TO PREDICTED RIDGING AND ABOVE NORMAL HEIGHTS.
ENHANCED PROBABILITIES OF BELOW MEDIAN PRECIPITATION ARE ALSO INDICATED FOR
MUCH OF THE SOUTHEASTERN CONUS IN ASSOCIATION WITH PREDICTED MEAN SURFACE HIGH
PRESSURE. THE POTENTIAL FOR RETURN FLOW AROUND THIS HIGH LEADS TO A SLIGHT
ENHANCEMENT OF ABOVE MEDIAN PRECIPITATION PROBABILITIES FOR SOUTHERN TEXAS.
NEAR TO ABOVE MEDIAN PRECIPITATION IS FAVORED FOR THE GREAT LAKES REGION AND
PARTS OF THE NORTHEAST IN ASSOCIATION WITH A PREDICTED TROUGH AND CONSISTENT
WITH NAEFS GUIDANCE. ENHANCED PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION ARE
ALSO INDICATED FOR THE ALASKA PANHANDLE EXTENDING TO THE NORTHWESTERN CONUS
AHEAD OF A TROUGH PREDICTED OVER THE GULF OF ALASKA. ANOMALOUS NORTHERLY MID
LEVEL FLOW ASSOCIATED WITH THE STRONG TROUGH PREDICTED OVER ALASKA LEADS TO
ENHANCED PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR WESTERN AND CENTRAL
PORTIONS OF THE STATE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 25% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, 10% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 25% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, 5% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 10, AND 5% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO MODERATELY HIGH MODEL SPREAD OVER THE CONUS.

FORECASTER: SCOTT HANDEL

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
MARCH 16

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:
19890227 - 19900214 - 19550223 - 19590207 - 19630312


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:
19890227 - 19550223 - 19590207 - 20060220 - 19820207


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 05 - 09 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 07 - 13 2017

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