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FXUS06 KWBC 221913
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED MARCH 22 2017

6-10 DAY OUTLOOK FOR MAR 28 - APR 01, 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN PREDICTED OVER NORTH AMERICA. TROUGHS ARE EXPECTED OVER
PARTS OF THE ALEUTIANS AND WESTERN ALASKA, AND THE WESTERN CONUS, WHILE RIDGES
ARE FORECAST OVER PARTS OF EASTERN ALASKA AND WESTERN CANADA, AND IN THE
EASTERN U.S. TODAY`S MANUAL BLEND DEPICTS NEGATIVE HEIGHT ANOMALIES OVER THE
ALEUTIANS, WESTERN ALASKA, PARTS OF THE SOUTHWESTERN CONUS, AND MAINE WITH
POSITIVE HEIGHT ANOMALIES ACROSS THE REMAINDER OF THE CONUS. THE GREATEST
WEIGHT FOR THE BLENDED HEIGHT FORECAST WAS GIVEN TO THE EUROPEAN ENSEMBLE MEAN
SOLUTION BASED ON CONSIDERATIONS OF RECENT SKILL AND ANALOG CORRELATIONS, WHICH
MEASURE HOW CLOSELY THE FORECAST PATTERN MATCHES CASES THAT HAVE OCCURRED IN
THE PAST.

ABOVE NORMAL HEIGHTS AND 500-HPA SOUTHWESTERLY FLOW ENHANCE PROBABILITIES FOR
ABOVE NORMAL TEMPERATURES FOR EASTERN ALASKA AND THE ALASKA PANHANDLE. BELOW
NORMAL HEIGHTS TILT THE ODDS TO BELOW NORMAL TEMPERATURES FOR WESTERN ALASKA,
THE ALEUTIANS. AN ANOMALOUS RIDGE IN THE EASTERN U.S. ENHANCES THE LIKELIHOOD
FOR ABOVE NORMAL TEMPERATURES OVER MOST OF THE EASTERN CONUS. HOWEVER, A SLIGHT
TEMPERATURE GRADIENT IS EXPECTED OVER THE NORTHEAST. NEAR TO ABOVE NORMAL
TEMPERATURES ARE FAVORED FOR THE WESTERN CONUS, CONSISTENT WITH CALIBRATED
REFORECAST TEMPERATURE TOOLS FROM GFS ENSEMBLE FORECASTS.

MULTIPLE SHORTWAVE TROUGHS AND ENHANCED INFLOW FROM THE GULF OF MEXICO INCREASE
CHANCES FOR MUCH OF THE CONUS, FROM THE ROCKIES TO THE EAST COAST. THE HIGHEST
ODDS FOR ABOVE MEDIAN PRECIPITATION ARE FORECAST FOR THE SOUTH-CENTRAL U.S.
WHERE GFS AND ECWMF ENSEMBLE MEANS INDICATE 1.5 TO 2.0 INCHES OF PRECIPITATION
DURING THIS 5-DAY PERIOD. BELOW-MEDIAN PRECIPITATION IS FAVORED FOR CALIFORNIA
DUE TO RIDGING UPSTREAM. ONSHORE FLOW FAVORS ABOVE MEDIAN PRECIPITATION FOR
PARTS OF SOUTHERN ALASKA AND THE ALASKA PANHANDLE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY`S OPERATIONAL
0Z ECMWF CENTERED ON DAY 8, AND 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 8


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

8-14 DAY OUTLOOK FOR MAR 30 - APR 05, 2017

TODAY`S ENSEMBLE MEAN DYNAMICAL MODEL FORECASTS ARE IN GOOD AGREEMENT ON THE
PREDICTED 500-HPA CIRCULATION PATTERN OVER NORTH AMERICA FOR THE WEEK-2 PERIOD.
TROUGHS ARE FORECAST OVER THE ALEUTIANS, PARTS OF THE THE WESTERN AND CENTRAL
CONUS, WHILE RIDGES ARE FORECAST OVER PARTS OF EASTERN ALASKA AND WESTERN
CANADA. WEST-SOUTHWESTERLY ZONAL FLOW IS INDICATED OVER THE EASTERN SEABOARD.
ENSEMBLE SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE MAJORITY OF THE
FORECAST DOMAIN.

ABOVE NORMAL HEIGHTS AND/OR ANOMALOUS SOUTHEASTERLY FLOW TILT THE ODDS TO NEAR
TO ABOVE NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL AND EASTERN U.S. ANOMALOUS
NORTHERLY FLOW ENHANCES PROBABILITIES FOR BELOW NORMAL TEMPERATURES FOR PARTS
OF MAINE.ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE SOUTHWESTERN CONUS,
WHILE BELOW NORMAL TEMPERATURES ARE INDICATED FOR WESTERN ALASKA, CONSISTENT
WITH CALIBRATED REFORECAST TEMPERATURE TOOLS FROM GFS ENSEMBLE FORECASTS.

THE PRECIPITATION PATTERN FORECAST FOR THE WEEK-2 PERIOD IS SIMILAR TO THE 6-10
DAY PERIOD. ABOVE NORMAL HEIGHTS TILT THE ODDS TO BELOW MEDIAN PRECIPITATION
FOR CALIFORNIA, AND PARTS OF THE NEVADA. PRECIPITATION ESTIMATES FROM THE GEFS
ENSEMBLE MEMBERS FAVOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE REMAINDER OF
THE CONUS, CONSISTENT WITH A LONGWAVE TROUGH OVER THE WEST-CENTRAL CONUS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 40% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% OF TODAY`S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND AMONG THE FORECAST TOOLS.

FORECASTER: LUKE H

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
APRIL 20

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:
19720310 - 19780330 - 20040324 - 19540405 - 19860326


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:
19780330 - 20040323 - 19720309 - 19860326 - 19890310


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 28 - APR 01, 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 30 - APR 05, 2017

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