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FXUS06 KWBC 261902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED JULY 26 2017

6-10 DAY OUTLOOK FOR AUG 01 - 05 2017

TODAY`S DYNAMICAL MODELS ARE IN GOOD AGREEMENT ON THE PREDICTED
MID-TROPOSPHERIC CIRCULATION PATTERN ACROSS THE FORECAST DOMAIN. THE OFFICIAL
BLENDED HEIGHT FIELD DEPICTS MEAN TROUGHS OVER NORTHWEST ALASKA/BERING STRAIT,
THE GULF OF ALASKA/EASTERN PACIFIC, AND THE EASTERN CONUS, WITH MEAN RIDGES
OVER NORTHEAST ALASKA, THE ALEUTIANS, AND THE WESTERN INTERIOR CONUS. THERE ARE
RELATIVELY MINOR DIFFERENCES BETWEEN THE DYNAMICAL MODELS IN PREDICTED
AMPLITUDE AND PHASE OF THESE KEY LONG-WAVE FEATURES. ONE OF THE MORE UNCERTAIN
ASPECTS OF THIS FORECAST INVOLVES THE LONG-WAVE TROUGH ANTICIPATED OVER THE
EASTERN CONUS. INSPECTION OF MODEL GUIDANCE INDICATES SEVERAL SHORTWAVES
EMBEDDED WITHIN THE LONGWAVE TROUGH ARE LIKELY TO MOVE ACROSS THE GREAT LAKES
REGION AND NORTHEAST, RESULTING IN VARIABLE TEMPERATURE AND PRECIPITATION
PATTERNS DURING THE 6-10 DAY PERIOD. THIS IS WHY A SUBSTANTIAL AREA OF
NEAR-NORMAL TEMPERATURES, AND NEAR TO BELOW-NORMAL PRECIPITATION, IS FAVORED
ACROSS THESE REGIONS. AT THE 5820 METER LEVEL, THE VARIOUS SPAGHETTI DIAGRAMS
SHOW LOW TO MODERATE SPREAD AMONG THE INDIVIDUAL ENSEMBLE MEMBERS OVER THE
CONUS.

ODDS FOR ABOVE NORMAL TEMPERATURES ARE ELEVATED ACROSS ALASKA, MOST AREAS WEST
OF THE CONTINENTAL DIVIDE, THE NORTHERN GREAT PLAINS AND WESTERN NEBRASKA,
NORTHWEST MINNESOTA, NEW ENGLAND AND THE IMMEDIATE MID-ATLANTIC COAST, THE
FLORIDA PENINSULA, AND SOUTHERN PORTIONS OF TEXAS. THIS IS GENERALLY DUE TO THE
PREDICTED PRESENCE OF 500-HPA RIDGES AND ASSOCIATED ABOVE NORMAL HEIGHTS. BELOW
NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE CENTRAL AND SOUTHERN GREAT
PLAINS, MUCH OF THE MISSISSIPPI AND OHIO VALLEYS, THE TENNESSEE VALLEY, MOST OF
THE SOUTHEAST (EXCLUDING FLORIDA), AND THE CENTRAL AND SOUTHERN APPALACHIANS.
THIS IS DUE TO THE PREDICTED PRESENCE OF A NEARBY 500-HPA TROUGH AND LIKELIHOOD
FOR ENHANCED RAINFALL, AND IS CONSISTENT WITH VARIOUS DYNAMICAL MODEL
TEMPERATURE FORECASTS, AND THE CPC CONSOLIDATION TEMPERATURE FORECAST.

ABOVE NORMAL PRECIPITATION IS FAVORED IN PORTIONS OF ALASKA, CENTRAL AND
SOUTHERN PORTIONS OF BOTH THE INTERMOUNTAIN REGION AND ROCKIES, THE CENTRAL AND
SOUTHERN PLAINS, AND FROM THE LOWER MISSISSIPPI VALLEY EASTWARD TO THE SOUTHERN
ATLANTIC COAST. THIS IS ATTRIBUTED TO THE EXPECTATION OF APPROACHING 500-HPA
TROUGHS AND ASSOCIATED WIDESPREAD ASCENT OF AIR, AND IN THE SOUTHWESTERN CONUS,
THE SOUTHWEST SUMMER MONSOON. BELOW NORMAL PRECIPITATION IS FAVORED ACROSS A
LARGE PORTION OF THE NORTHERN CONUS, INCLUDING THE NORTHERN INTERMOUNTAIN
REGION, THE NORTHERN ROCKIES AND NORTHERN PLAINS, EASTERN PORTIONS OF THE
CENTRAL PLAINS, THE UPPER AND MIDDLE MISSISSIPPI VALLEY, MOST OF THE GREAT
LAKES REGION AND NORTHEAST, THE OHIO VALLEY, AND THE MID-ATLANTIC. THESE
FAVORED AREAS OF BELOW NORMAL PRECIPITATION ARE GENERALLY ASSOCIATED WITH AN
ANTICIPATED 500-HPA RIDGE AND THE SUBSIDENCE AREA ASSOCIATED WITH THE EASTERN
CONUS TROUGH. HOWEVER, AS NOTED EARLIER, PROBABILITIES ARE LOW ACROSS THE GREAT
LAKES AND NORTHEAST DUE TO LIKELY SHORTWAVE ACTIVITY EMBEDDED WITHIN THE
LONGWAVE TROUGH.

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, 10% OF TODAY`S OPERATIONAL 6Z GFS
CENTERED ON DAY 8, 25% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN 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 MODEL AGREEMENT, AND REASONABLE AGREEMENT AMONG THE VARIOUS TEMPERATURE
AND PRECIPITATION TOOLS.

8-14 DAY OUTLOOK FOR AUG 03 - 09 2017

TODAY`S MODELS ARE IN FAIR AGREEMENT ON THE PREDICTED WEEK-2 500-HPA
CIRCULATION PATTERN ACROSS THE FORECAST DOMAIN. TO A FIRST APPROXIMATION, THE
EXPECTED PATTERN IS SIMILAR TO THAT FOR DAYS 6-10, BUT THERE ARE INCREASING
DIFFERENCES IN THE PREDICTED AMPLITUDES AND PHASES OF THE MAJOR LONG-WAVES. FOR
EXAMPLE, MOST OF THE ENSEMBLE MEAN SOLUTIONS DEAMPLIFY THE WESTERN CONUS RIDGE,
AND NO LONGER PREDICT RIDGING ACROSS THE ALEUTIANS, WHILE THE DETERMINISTIC 0Z
AND 6Z GFS RUNS PREDICT HIGHLY AMPLIFIED RIDGES IN THIS REGION AND IMMEDIATELY
UPSTREAM TROUGHS OVER THE FAR EASTERN PACIFIC. ENSEMBLE SPREAD IS MODERATE OVER
MUCH OF THE FORECAST DOMAIN.

THE PREDICTED WEEK-2 TEMPERATURE PATTERN IS SIMILAR TO THAT ANTICIPATED DURING
THE 6-10 DAY PERIOD, THOUGH THERE IS AN EXPECTED SLIGHT WESTWARD SHIFT OF THE
TEMPERATURE ANOMALY PATTERN ACROSS THE ATLANTIC COAST STATES AND APPALACHIANS.
THIS IS CONSISTENT WITH A PREDICTED INCREASE IN COVERAGE OF FAVORED
ABOVE-NORMAL PRECIPITATION ACROSS THE SAME GENERAL AREA. WITH THE MANUAL
BLENDED 500-HPA HEIGHT FIELD PREDICTING A SOUTHWARD SHIFT OF THE AXIS OF 5940
METER HEIGHTS ACROSS THE SOUTHWEST (COMPARED TO THE PAST 2 DAYS), IT IS THOUGHT
THAT THE NORTHERN EXTENT OF MONSOONAL MOISTURE MAY ALSO TREND SOUTHWARD WITH
TIME.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 25% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 30% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 25% 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 FAIR MODEL AGREEMENT, OFFSET BY THE PREDICTION OF VERY MODEST 500-HPA HEIGHT
ANOMALIES AND SURFACE PRECIPITATION ANOMALIES.

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
AUGUST 17

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:
19560809 - 20010809 - 19930730 - 19860720 - 19960807


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:
19560808 - 20010808 - 19860720 - 19960807 - 19930729


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 01 - 05 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 03 - 09 2017

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