Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2
757
FXUS06 KWBC 281907
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED JUNE 28 2017

6-10 DAY OUTLOOK FOR JUL 04 - 08 2017

TODAY`S MODELS ARE IN FAIR AGREEMENT ON THE PREDICTED 500-HPA FLOW PATTERN OVER
THE FORECAST DOMAIN. MOST SOLUTIONS GENERALLY PREDICT TROUGHS OVER THE BERING
SEA, THE EASTERN GULF OF ALASKA AND ADJACENT PORTIONS OF BRITISH COLUMBIA/U.S.
PACIFIC NORTHWEST, AND THE EASTERN CONUS. RIDGING IS GENERALLY FAVORED OVER
MUCH OF MAINLAND ALASKA, THE GREAT PLAINS, AND OVER THE SOUTHERN CONUS. AS
USUAL, THERE ARE VARIATIONS IN THE PREDICTED AMPLITUDES, PHASES, AND
ORIENTATIONS OF THESE LONG-WAVE FEATURES FROM THE GENERAL CONSENSUS PATTERN.
THE DETERMINISTIC 0Z ECMWF RUN DIFFERS FROM THE OTHER RUNS IN THAT IT FORECASTS
THE BERING SEA AND BRITISH COLUMBIA-VICINITY TROUGHS ABOUT 5-10 DEGREES
LONGITUDE FARTHER EAST. TODAY`S MANUAL 500-HPA BLEND FAVORS TODAY`S 0Z ECMWF
ENSEMBLE MEAN, WHICH HAS SHOWN HIGHER RECENT SKILL THAN THE OTHER MODELS.

TODAY`S TEMPERATURE TOOLS (FROM THE DYNAMICAL MODELS, CALIBRATED REFORECAST
GEFS AND ECMWF, AND THE AUTO BLEND TEMPERATURES) GENERALLY FAVOR AN ELEVATED
CHANCE OF BELOW-NORMAL TEMPERATURES FOR EXTREME SOUTHEASTERN ALASKA AND THE
ALASKA PANHANDLE. THIS FORECAST AREA OF BELOW-NORMAL TEMPERATURES, AND ADJACENT
AREAS OF PREDICTED NEAR-NORMAL TEMPERATURES (INCLUDING WASHINGTON STATE) ARE
ASSOCIATED WITH A WEAK 500-HPA TROUGH AND HEIGHT ANOMALIES CLOSE TO ZERO. FOR
ALL REMAINING AREAS OF THE CONUS AND ALASKA, WHICH INCLUDES THE VAST MAJORITY
OF THE COUNTRY, ABOVE-NORMAL TEMPERATURES ARE FAVORED, GENERALLY ASSOCIATED
WITH 500-HPA RIDGING AND/OR MODESTLY POSITIVE HEIGHT ANOMALIES. THE FAVORED
ABOVE-NORMAL TEMPERATURES IN FAR WESTERN ALASKA ARE ALSO DUE, IN PART, TO
RELATIVELY WARM SEA-SURFACE TEMPERATURES.

ABOVE-MEDIAN PRECIPITATION IS FAVORED FOR MOST OF ALASKA SOUTH OF THE BROOKS
RANGE, THE MIDDLE MISSISSIPPI VALLEY, SOUTHERN GREAT LAKES REGION, OHIO AND
TENNESSEE VALLEYS, MUCH OF THE APPALACHIANS, AND THE ATLANTIC COAST STATES FROM
NEW YORK TO SOUTH CAROLINA. THESE AREAS OF PREDICTED WETTER-THAN-MEDIAN
PRECIPITATION ARE GENERALLY ATTRIBUTED TO 500-HPA TROUGHS AND RELATED STORM
TRACKS, AND, ESPECIALLY IN THE SOUTHEAST, SEASONAL CONVECTION. BELOW-MEDIAN
PRECIPITATION IS FAVORED FOR APPROXIMATELY THE NORTHWESTERN QUARTER OF THE
CONUS INCLUDING MOST OF MINNESOTA, AND FOR NORTHEASTERN ALASKA. BELOW-MEDIAN
PRECIPITATION IS ALSO FAVORED FROM THE SOUTHERN PLAINS EASTWARD ACROSS THE
LOWER MISSISSIPPI VALLEY TO THE CENTRAL FLORIDA PANHANDLE, AND FOR MAINE. THESE
AREAS OF PREDICTED DRIER-THAN-MEDIAN PRECIPITATION ARE ASSOCIATED WITH 500-HPA
RIDGES AND/OR WEAK POSITIVE HEIGHT ANOMALIES.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 5% OF TODAY`S OPERATIONAL 6Z GFS
CENTERED ON DAY 8, 25% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
5% 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: NEAR-AVERAGE, 3 OUT OF 5, DUE TO
FAIR MODEL AGREEMENT TODAY.

8-14 DAY OUTLOOK FOR JUL 06 - 12 2017

THE ENSEMBLE MEAN 500-HPA HEIGHT FORECASTS FOR THE WEEK-2 PERIOD DEPICT A
CIRCULATION PATTERN THAT IS SIMILAR TO THE ONE EXPECTED FOR THE 6-10 DAY
PERIOD. HOWEVER, THE 6Z DETERMINISTIC GFS SOLUTION DEPICTS A SIGNIFICANTLY MORE
AMPLIFIED LONG-WAVE PATTERN OVER THE EASTERN GULF OF ALASKA AND CONUS. AS IS
OFTEN THE CASE, THIS INCREASED AMPLITUDE OFTEN RESULTS IN TIGHTENING THE
DOWNSTREAM WAVELENGTHS OVER THE CONUS. THE DOWNSTREAM FEATURES PREDICTED IN THE
6-10 PERIOD (A RIDGE OVER THE PLAINS AND A TROUGH OVER THE EAST) ARE EXPECTED
BY THE 6Z GFS RUN TO BE SHIFTED WESTWARD BY ABOUT 10 DEGREES. THIS OUTLIER
SOLUTION IS BEING DISCOUNTED TODAY.

THE ANTICIPATED WEEK-2 SURFACE TEMPERATURE AND PRECIPITATION PATTERNS ARE
SIMILAR TO THOSE FOR THE 6-10 DAY PERIOD. SLIGHT MODERATION IN TEMPERATURES IS
EXPECTED OVER THE PACIFIC NORTHWEST, COMPARED TO THE 6-10 DAY PERIOD. MOISTURE
RELATED TO THE ONSET PHASE OF THE SOUTHWEST MONSOON IS FORECAST TO AFFECT NEW
MEXICO, AND PARTS OF ADJACENT STATES, DURING WEEK-2.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% 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, 30% 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: NEAR-AVERAGE, 3 OUT OF 5, DUE
TO WEAK MEAN 500-HPA ANOMALIES IN THE MANUAL BLEND ACROSS MUCH OF THE FORECAST
DOMAIN, YET DECENT AGREEMENT AMONG THE SURFACE SPECIFICATION TOOLS.

FORECASTER: ANTHONY A

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
JULY 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:
19850618 - 20030608 - 19600623 - 19650706 - 19580615


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:
19580625 - 19850618 - 19960710 - 19630617 - 19600622


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 04 - 08 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 06 - 12 2017

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     OREGON      A    B     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       A    B     NEVADA      A    N
W MONTANA   A    B     E MONTANA   A    B     WYOMING     A    B
UTAH        A    B     ARIZONA     A    N     COLORADO    A    N
NEW MEXICO  A    A     N DAKOTA    A    B     S DAKOTA    A    B
NEBRASKA    A    B     KANSAS      A    N     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    B     W TEXAS     A    N
MINNESOTA   A    B     IOWA        A    N     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    N     WISCONSIN   A    N
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     A    N     NEW HAMP    A    N     MAINE       A    N
MASS        A    N     CONN        A    A     RHODE IS    A    N
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    N     FL PENIN    A    N     AK N SLOPE  A    A
AK ALEUTIAN A    A     AK WESTERN  A    A     AK INT BSN  A    A
AK S INT    N    A     AK SO COAST N    A     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.

$$




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.