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FXUS06 KWBC 301936
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI SEPTEMBER 30 2016

6-10 DAY OUTLOOK FOR OCT 06 - 10 2016

TODAY`S MODEL SOLUTIONS AGAIN EXHIBIT GOOD AGREEMENT ON THE FORECAST
CIRCULATION OVER NORTH AMERICA. GENERALLY, THE MODELS PREDICT TROUGHING OVER
THE BERING SEA, RIDGING OVER MOST OF ALASKA, TROUGHING OVER THE WESTERN CONUS,
AND RIDGING CENTERED OVER FAR EASTERN CANADA. SOME OF THE SUBTLE MODEL
DIFFERENCES FROM YESTERDAY`S OUTLOOK ARE LESS APPARENT AS THE VARIOUS GLOBAL
MODELS HAVE FURTHER CONVERGED. RUN-TO-RUN CONTINUITY IS LIKEWISE IMPROVED, SO
DETERMINISTIC SOLUTIONS ARE GIVEN SLIGHTLY HIGHER WEIGHTS IN TODAY`S OFFICIAL
500-HPA HEIGHT MANUAL BLEND.

ANOMALOUS TROUGHING IS EXPECTED EARLY IN THE PERIOD OVER THE NORTHERN PLAINS
AND UPPER MIDWEST AS A MID-LEVEL TROUGH PROGRESSES EASTWARD, RESULTING IN A
SLIGHT TILT TOWARD BELOW-NORMAL TEMPERATURES FOR THAT REGION EXTENDING INTO
PARTS OF THE INTERIOR WEST. ABOVE-NORMAL TEMPERATURES REMAIN FAVORED FARTHER
EAST, WHERE ANOMALOUS SOUTHERLY FLOW IS EXPECTED AHEAD OF THE AFOREMENTIONED
TROUGH.

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 COAST FAVORS A STORM TRACK FROM THE PACIFIC
NORTHWEST TO THE CENTRAL AND NORTHERN GREAT PLAINS. RIDGING FAVORS BELOW-MEDIAN
PRECIPITATION FOR PARTS OF THE INTERIOR SOUTHEAST EXTENDING WESTWARD TO THE
SOUTHWEST. THE MODELS HAVE BEGUN TO CONVERGE ON A SOLUTION REGARDING THE TRACK
OF HURRICANE MATTHEW. AT THIS POINT, PRECIPITATION IMPACTS ARE MOST LIKELY TO
BE OFFSHORE DURING THIS PERIOD, THOUGH FORECAST AMPLIFICATION OF THE
MIDLATITIDE TROUGH LATE IN THE PERIOD INCREASES THE ODDS OF ABOVE-MEDIAN
PRECIPITATION OVER PARTS OF NEW ENGLAND WHERE ENTRAINMENT OF TROPICAL MOISTURE
IS POSSIBLE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% 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 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, 20% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND 15% 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 VARIOUS FORECAST TOOLS.


8-14 DAY OUTLOOK FOR OCT 08 - 14 2016

UNCERTAINTY REMAINS ELEVATED HEADING INTO THE WEEK-2 PERIOD AS THE FORECAST
CIRCULATION PATTERN EXHIBITS SOME LARGE CHANGES RELATIVE TO THE 6-10 DAY
PERIOD. TROUGH AMPLIFICATION IS FORECAST OVER THE EASTERN GREAT LAKES AND
NORTHEAST, AS WELL AS OVER THE NORTHEAST PACIFIC. LOW-AMPLITUDE RIDGING IS
FORECAST OVER THE CENTRAL CONUS. THE VARIOUS ENSEMBLE MEAN SOLUTIONS HAVE
TRENDED TOWARD THIS SOLUTION OVER THE PAST DAY, AND RECENT RUNS OF THE
DETERMINISTIC GFS HAVE MAINTAINED GOOD RUN-TO-RUN CONTINUITY.

OBJECTIVE TOOLS RESULTING FROM POST-PROCESSING OF THE GEFS AND ECMWF CONTINUE
TO FAVOR ABOVE-NORMAL TEMPERATURES ACROSS MUCH OF THE CONUS. THIS SEEMS FAIRLY
COUNTER INTUITIVE GIVEN ANOMALOUS TROUGHING FORECAST OVER THE NORTHEAST, AND
STATISTICAL TOOLS DEPICT A COOLER SOLUTION OVER THE GREAT LAKES AND NORTHEAST.
THEREFORE, PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES OVER THAT REGION REMAIN
ELEVATED, BUT ONLY SLIGHTLY SO.

A WEAKLY ENHANCED STORM TRACK IS FORECAST OVER THE NORTHER TIER OF THE CONUS,
THOUGH THE HIGHEST PROBABILITIES ARE SHIFTED TOWARD THE PACIFIC NORTHWEST,
DOWNSTREAM OF THE FORECAST TROUGH AXIS. BELOW-MEDIAN PRECIPITATION IS MORE
LIKELY ACROSS MUCH OF THE SOUTHERN TIER OF THE CONUS UNDER ANOMALOUS RIDGING
AND ANOMALOUS MID-LEVEL NORTHERLY FLOW. UNCERTAINTY WITH RESPECT TO THE TRACK
OF HURRICANE MATTHEW IS LESS LIKELY TO IMPACT THIS PERIOD, THOUGH THE TROUGH
AMPLIFICATION MENTIONED IN THE 6-10 DAY FORECAST DISCUSSION COINCIDES WITH THE
EARLY PART OF THIS PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15% 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, 15% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, AND 40% OF TODAY`S 0Z EUROPEAN ENSEMBLE
MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO FAIRLY GOOD AGREEMENT AMONG FORECAST MODELS, OFFSET BY UNCERTAINTY REGARDING
THE STRENGTH AND DURATION OF A FORECAST TROUGH AMPLIFICATION OVER THE NORTHEAST
CONUS.

FORECASTER: STEPHEN BAXTER

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:
19970911 - 19981007 - 19571002 - 20080923 - 19680920


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:
19970911 - 19571003 - 19940909 - 19981008 - 20080925


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 06 - 10 2016

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 08 - 14 2016

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