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FXUS06 KWBC 031950
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON AUGUST 03 2015

6-10 DAY OUTLOOK FOR AUG 09 - 13 2015

TODAY`S MODELS EXHIBIT VERY GOOD AGREEMENT ON THE PREDICTED 500-HPA FLOW
PATTERN DURING THE 6-10 DAY PERIOD. THE MODELS GENERALLY DEPICT A TROUGH OVER
WESTERN ALASKA, A TROUGH NEAR THE WEST COAST OF THE CONUS, RIDGING OVER THE
CENTRAL CONUS, AND A TROUGH NEAR THE EAST COAST. THE ENVIRONMENT CANADA MODEL
DEPICTS A SLIGHTLY STRONGER RIDGE OVER THE CENTRAL CONUS WITH THE WEAKEST
REPRESENTATION IN THE EUROPEAN CENTER SOLUTIONS. THERE ARE SLIGHT VARIATIONS IN
THE POSITION OF THE TROUGH NEAR THE WEST COAST, WITH THE GFS ENSEMBLES
PREDICTING A GENERALLY SHARPER TROUGH, WITH THE WEAKEST AND BROADEST TROUGH IN
THE 0Z CANADIAN ENSEMBLE MEAN SOLUTION.

THE MANUAL BLEND IS CONSTRUCTED FROM EUROPEAN CENTER AND GFS BASED MODEL
SOLUTIONS, AS THOSE MODELS HAD GENERALLY HIGHER ANALOG CORRELATION SCORES AND
ANOMALY CORRELATION SCORES OVER THE PAST 60 DAYS. ANALOG CORRELATIONS OFF THE
CANADIAN ENSEMBLE MEAN SOLUTIONS WERE VERY LOW TODAY, INDICATING A MISALIGNMENT
OF THE MODEL OUTPUT WITH THE HISTORICAL RECORD.

THE RESULTANT UPPER-LEVEL PATTERN FAVORS ABOVE NORMAL TEMPERATURES ACROSS THE
ENTIRE SOUTHERN TIER OF THE CONUS AND ACROSS THE CENTRAL GREAT PLAINS, ALL DUE
TO THE FORECAST RIDGING. BELOW NORMAL TEMPERATURES OVER THE GREAT BASIN AND
NORTHERN ROCKIES ARE FAVORED DUE TO THE INFLUENCE OF THE TROUGH PREDICTED OVER
THE PACIFIC NORTHWEST. TROUGHING ALOFT AND IN THE LOW LEVELS FAVORS BELOW
NORMAL TEMPERATURES FROM THE GREAT LAKES TO THE NORTHEAST. A SOUTHERLY
COMPONENT TO THE LOW-LEVEL FLOW FAVORS ABOVE NORMAL TEMPERATURES OVER ALASKA,
SOUTH OF THE ALASKA RANGE.

SOUTHWESTERLY FLOW FAVORS ABOVE MEDIAN PRECIPITATION FOR SOUTHERN ALASKA. THE
MAIN STORM TRACK OVER THE CONUS IS LIKELY TO BE OVER THE NORTHERN TIER OF THE
CONUS, DEFLECTED NORTHWARD BY THE LARGE RIDGE FORECAST OVER THE CENTRAL CONUS.
THEREFORE, ABOVE MEDIAN PRECIPITATION IS FAVORED FROM THE PACIFIC NORTHWEST TO
THE UPPER GREAT LAKES, WHILE BELOW MEDIAN PRECIPIATION IS FAVORED FROM THE
SOUTHWEST TO THE CENTRAL ROCKIES TO THE TENNESSEE VALLEY. TROUGHING ALONG THE
EAST COAST FAVORS ABOVE MEDIAN PRECIPITATION FROM THE SOUTHEAST COAST TO THE
MID-ATLANTIC AND NORTHEAST.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 25% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 10% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND
10% OF YESTERDAY`S OPERATIONAL 12Z ECMWF CENTERED ON DAY 7


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG VARIOUS TOOLS, OFFSET SLIGHTLY BY UNCERTAINTY OVER THE
NORTHERN GREAT PLAINS AND SOME DISAGREEMENT BETWEEN THE REFORECAST TOOLS IN THE
PRECIPITATION PATTERN.

8-14 DAY OUTLOOK FOR AUG 11 - 17 2015

MODEL FORECASTS DURING THE WEEK-2 PERIOD FAVOR RIDGING OVER THE CENTRAL CONUS,
WITH WEAK TROUGHING FROM EASTERN ALASKA TO THE PACIFIC NORTHWEST, AND WEAK
TROUGHING FROM THE NORTHEAST TO THE MID-ATLANTIC. ANOMALIES ARE GENERALLY WEAK,
ALTHOUGH THE 6Z DETERMINISTIC GFS DEVELOPS A DEEP TROUGH OVER THE EASTERN THIRD
OF THE CONUS. THAT SOLUTION IS DISCOUNTED DUE TO THE AMPLITUDE, BUT THE OVERALL
PATTERN AGREES WITH THE REMAINING ENSEMBLE MEAN SOLUTIONS.

THE 500-HPA HEIGHT MANUAL BLEND CONSISTS OF MOSTLY EUROPEAN CENTER AND GFS
BASED MODEL SOLUTIONS, ALTHOUGH A SMALL PORTION OF THE BLEND IS FROM
YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN.  THE ANALOG CORRELATION SCORES FROM THE
ENVIRONMENT CANADA MODELS ARE HIGHER DURING THE WEEK-2 PERIOD, BUT STILL LOWER
THAN OTHER MODELS. IN GENERAL, THE 0Z MODELS HAD LOWER ANALOG CORRELATION
SCORES, POTENTIALLY HINTING AT A SENSITIVITY TO THE INITIAL CONDITIONS NOT
IMPACTING THE 6Z MODEL SUITE.

THE UPPER-LEVEL PATTERN, WITH GENERALLY NEAR OR ABOVE AVERAGE HEIGHTS, FAVORS
ABOVE NORMAL TEMPERATURES FOR MOST OF ALASKA AND THE CONUS. THE EXCEPTIONS ARE
THE NORTHERN HALF OF ALASKA, THE NORTHERN ROCKIES, AND FROM THE LOWER GREAT
LAKES TO NEW ENGLAND, WHERE NEAR NORMAL TEMPERATURES ARE FAVORED.

WEAK TROUGHING OVER EASTERN ALASKA FAVORS BELOW (ABOVE) MEDIAN PRECIPITATION
OVER WESTERN (EASTERN) ALASKA, WHILE ABOVE MEDIAN PRECIPITATION IS FAVORED OVER
THE ALASKA PANHANDLE. RIDGING OVER THE CENTRAL CONUS AND A WEAKER TROUGH OVER
THE NORTHWEST (AS COMPARED TO THE 6-10 DAY PERIOD) FAVORS BELOW MEDIAN
PRECIPITATION FROM THE NORTHERN ROCKIES TO THE SOUTHWEST, EASTWARD TO THE
MISSISSIPPI VALLEY. ODDS FOR BELOW MEDIAN PRECIPITATION OVER THE SOUTHWEST ARE
LOWER DURING THIS PERIOD, SUGGESTING SOME POTENTIAL FOR A RETURN OF MONSOONAL
MOISTURE. TROUGHING NEAR THE EAST COAST SUPPORTS ABOVE MEDIAN PRECIPITATION
FROM THE GREAT LAKES TO NEW ENGLAND AND SOUTHWARD TO THE SOUTHEAST, EAST OF THE
APPALACHIANS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 25% OF
YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, AND 20% OF
YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO RELATIVELY GOOD AGREEMENT AMONG THE ENSEMBLE MEANS AND A RELATIVELY STABLE
PATTERN, OFFSET BY A FORECAST LOW-AMPLITUDE ANOMALIES.

FORECASTER: MATT ROSENCRANS

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 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:
19720808 - 19730715 - 19920730 - 19620723 - 19840715


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:
19720808 - 19840717 - 19620723 - 19730715 - 19560713


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 09 - 13 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 11 - 17 2015

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