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FXUS06 KWBC 281939
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED SEPTEMBER 28 2016

6-10 DAY OUTLOOK FOR OCT 04 - 08 2016

TODAY`S MODEL SOLUTIONS EXHIBIT GOOD AGREEMENT. GENERALLY, THE MODELS PREDICT
TROUGHING OVER THE BERING SEA, RIDGING OVER MOST OF ALASKA, TROUGHING OVER THE
WESTERN CONUS, AND RIDGING FROM HUDSON BAY TO THE SOUTHEAST COAST. MODEL
DIFFERENCES ARE EVIDENT OVER THE SOUTHEAST WHERE THE GFS-BASED AND ENVIRONMENT
CANADA MODEL SOLUTIONS HAVE BELOW AVERAGE HEIGHTS AND THE EUROPEAN CENTRE
MODELS DEPICT NEAR TO ABOVE NORMAL HEIGHTS. THE MANUAL BLEND CAPTURES THE
AFOREMENTIONED FEATURES FROM ALASKA TO THE WESTERN CONUS TO THE NORTHEAST, AND
INDICATES NEAR TO SLIGHTLY BELOW NORMAL HEIGHTS OVER MUCH OF THE SOUTHEAST.

RIDGING OVER ALASKA FAVORS ABOVE NORMAL TEMPERATURES, EXCEPT FOR THE NORTHERN
ALASKA PANHANDLE WHERE LOW-LEVEL EASTERLY FLOW COULD ALLOW SOME COOLER AIR TO
FILTER IN. TROUGHING OVER THE WEST INDICATES BELOW NORMAL TEMPERATURES ARE
FAVORED FROM THE WEST COAST TO THE HIGH PLAINS. MEAN RIDGING FAVORS ABOVE
NORMAL TEMPERATURES FOR MUCH OF THE EASTERN CONUS, WITH THE HIGHEST
PROBABILITIES OVER THE NORTHEAST.

THE TROUGH OVER THE BERING SEA IS LIKELY TO STEER STORMS TOWARD SOUTHWESTERN
ALASKA, WHICH ARE THEN LIKELY TO WEAKEN AS THEY APPROACH THE MEAN RIDGE OVER
ALASKA. TROUGHING OVER THE WEST FAVORS A STORM TRACK FROM THE PACIFIC NORTHWEST
TO THE CENTRAL AND NORTHERN GREAT PLAINS, WITH THE ASSOCIATED COLD FRONTS
DROPPING SOUTHWARD TO THE SOUTHERN GREAT PLAINS, FAVORING ABOVE MEDIAN
PRECIPITATION FOR THOSE REGIONS. RIDING FAVORS BELOW MEDIAN PRECIPITATION FROM
THE INTERIOR SOUTHEAST TO THE GREAT LAKES. THE POTENTIAL FOR TROPICAL CYCLONE
ACTIVITY TO IMPACT THE EAST COAST FAVORS ABOVE MEDIAN PRECIPITATION FOR MUCH OF
THE EAST COAST, ALTHOUGH PROBABILITIES ARE LOW. MODEL SOLUTIONS DEPICT IMPACTS
ANYWHERE FROM FLORIDA TO MAINE, WITH THE HIGHEST PROBABILITIES OF ABOVE MEDIAN
PRECIPITATION OVER FLORIDA AND THE NORTHEAST. ONE OF THOSE AREAS IS LIKELY TO
BE IMPACTED BY TROPICAL STORM MATTHEW, BUT UNCERTAINTY PRECLUDES ELIMINATING
EITHER POTENTIAL IMPACT AREA.

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


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG MODEL SOLUTIONS IN A MORE AMPLIFIED LONGWAVE PATTERN,
OFFSET SOMEWHAT BY INCREASED UNCERTAINTY DUE TO THE POTENTIAL IMPACTS OF
TROPICAL STORM MATTHEW.


8-14 DAY OUTLOOK FOR OCT 06 - 12 2016

UNCERTAINTY INCREASES QUITE A BIT INTO THE WEEK-2 PERIOD AS THE PREDICTED
ANOMALIES BECOME MUCH WEAKER AND MODEL DISAGREEMENT INCREASES. EUROPEAN CENTRE
FORECASTS ARE MORE AMPLIFIED AND SLOWER WITH THE PATTERN OVER THE NORTHERN
CONUS, WHILE THE ENVIRONMENT CANADA ENSEMBLE MEANS INDICATE RISING HEIGHTS OVER
THE SOUTHWEST. GFS BASED SOLUTIONS ARE A MIDDLE GROUND. THE MANUAL BLEND FAVORS
THE EUROPEAN AND CANADIAN MODELS TODAY AS THOSE MODELS HAVE HIGHER ANOMALY
CORRELATION SCORES DURING THE PAST 60 DAYS, ALTHOUGH THE GEFS BASED SOLUTIONS
HAVE ANALOG CORRELATION SCORES ON PAR WITH THE OTHER MODELS, SO THE FORECAST
PATTERNS ARE NOT INCONSISTENT WITH PRIOR OBSERVATIONS.

THE DEAMPLIFIED 500-HPA PATTERN RESULTS IN LOWER PROBABILITIES IN THE SURFACE
FORECASTS COMPARED TO THE 6-10 DAY PERIOD. BELOW NORMAL TEMPERATURES ARE
FAVORED OVER PORTIONS OF THE SOUTHWEST, GREAT BASIN, NORTHERN ROCKIES AND
NORTHERN HIGH PLAINS, BUT THE SIGNAL IS MUCH WEAKER THAN EARLIER PERIODS OR
FROM PRIOR DAYS. ABOVE NORMAL TEMPERATURES ARE FAVORED FROM THE GULF COAST
STATES TO THE GREAT LAKES AND EASTWARD, WITH THE STRONGEST SIGNAL OVER THE
NORTHEAST. THE LARGEST UNCERTAINTY EXISTS OVER THE MISSISSIPPI VALLEY, WHERE
THE MORE PROGRESSIVE MODELS HAVE COOLER TEMPERATURES.

RIDGING FORECAST IN THE 6-10 DAY PERIOD OVER ALASKA IS FORECAST TO SPLIT AND
ALLOW FOR SOME STORM ACTIVITY TO PUSH INTO WESTERN AND CENTRAL ALASKA. WEAK
RIDGING FORECAST TO BUILD IN OVER THE EASTERN PACIFIC FAVORS BELOW MEDIAN
PRECIPITATION FOR THE GREAT BASIN AND NORTHERN CALIFORNIA. WEAK TROUGHING OVER
THE ROCKIES FAVORS ABOVE MEDIAN PRECIPITATION FOR THE CENTRAL AND NORTHERN
PLAINS, AND UPPER GREAT LAKES. BELOW MEDIAN PRECIPITATION IS FORECAST OVER THE
INTERIOR SOUTHEAST AS THE MEAN LOW-LEVEL TROUGHING IS FORECAST TO STRETCH FROM
THE CAROLINA COAST TO FLORIDA AND ACROSS THE GULF OF MEXICO.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, 30% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, 10%
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% OF YESTERDAY`S
12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO
FAIR MODEL AGREEMENT OFFSET SOMEWHAT BY UNCERTAINTY ABOUT THE POTENTIAL IMPACTS
OF TROPICAL STORM MATTHEW AND WEAK 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
OCTOBER 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:
19960919 - 20081006 - 19981004 - 20010927 - 20071009


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:
19960920 - 20071010 - 20081005 - 19870917 - 19981004


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 04 - 08 2016

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 06 - 12 2016

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

                           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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