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FXUS06 KWBC 311937
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED AUGUST 31 2016

6-10 DAY OUTLOOK FOR SEP 06 - 10 2016

TODAY`S 500-HPA MODEL SOLUTIONS ARE IN GOOD AGREEMENT IN DEPICTING A FAIRLY
AMPLIFIED PATTERN OVER MUCH OF THE FORECAST DOMAIN. ANOMALOUS RIDGING IS
FORECAST OVER THE NORTHEASTERN PACIFIC AND EASTERN CANADA, WHILE AN ANOMALOUS
TROUGH IS DEPICTED OVER THE NORTHERN ROCKIES. THE VARIOUS DETERMINISTIC AND
ENSEMBLE MEAN SOLUTIONS FROM THE GFS AND ECMWF SYSTEMS ARE IN EXCELLENT
AGREEMENT, WHILE THE CANADIAN SOLUTION IS A BIT OF AN OUTLIER WITH THE TROUGH
CENTERED FARTHER WEST NEAR THE NORTHWEST COAST. THE CANADIAN SOLUTION IS NOT
INCLUDED IN TODAY`S OFFICIAL MANUAL BLEND.

ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER THE CENTRAL AND EASTERN CONUS, WITH
THE HIGHEST PROBABILITIES INDICATED NEAR THE ANOMALOUS RIDGE AXIS OVER THE
NORTHEASTERN CONUS AND GREAT LAKES. SOME WEAKNESS IN THE SUBTROPICAL RIDGE IS
POSSIBLE NEARER THE SOUTHEAST COAST, AND SO PROBABILITIES ARE LOWER OVER THAT
REGION. THERE ARE ENHANCED PROBABILITIES FOR BELOW-NORMAL TEMPERATURES FOR MUCH
OF THE WESTERN CONUS IN ASSOCIATION WITH A PREDICTED TROUGH. BELOW-NORMAL
TEMPERATURES ARE ALSO FAVORED FOR PARTS OF NORTHERN ALASKA UNDERNEATH ANOMALOUS
NORTHERLY MID-LEVEL FLOW. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR
SOUTHWESTERN ALASKA AND THE ALEUTIANS DUE IN PART TO ABOVE-NORMAL SEA SURFACE
TEMPERATURES IN ADJACENT WATERS.

THERE ARE ENHANCED PROBABILITIES FOR NEAR- TO ABOVE- MEDIAN PRECIPITATION FOR
MUCH OF THE NORTHWESTERN AND NORTH-CENTRAL CONUS IN ASSOCIATION WITH A MEAN
TROUGH FORECAST NEAR THE NORTHERN ROCKIES. BELOW-MEDIAN PRECIPITATION IS
FAVORED FOR PARTS OF THE EASTERN CONUS NEAR THE RIDGE AXIS. SOME UNCERTAINTY
EXISTS ALONG THE IMMEDIATE EASTERN SEABOARD DUE TO REMNANTS OF TROPICAL STORM
HERMINE VERY EARLY IN THE PERIOD OVER THE NORTHEAST COAST, WHILE INVEST 92L
COULD IMPACT PARTS OF THE SOUTHEAST COAST BY THE END OF THE PERIOD.
ABOVE-MEDIAN PRECIPITATION IS SLIGHTLY FAVORED FOR SOUTHEASTERN NEW MEXICO AND
WESTERN TEXAS DUE TO THE POTENTIAL FOR MOIST MONSOONAL FLOW TO AFFECT THESE
REGIONS. PRECIPITATION ESTIMATES FROM THE GFS AND ECMWF ENSEMBLE MEMBERS FAVOR
BELOW-MEDIAN PRECIPITATION FARTHER TO THE NORTH FOR PARTS OF THE CENTRAL
ROCKIES AND GREAT BASIN.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 25% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 15% OF
TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 30% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 20% OF TODAY`S OPERATIONAL 0Z ECMWF
CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG THE VARIOUS MODELS, OFFSET SLIGHTLY BY UNCERTAINTY IN THE
PRECIPITATION OUTLOOK OVER THE EAST COAST.


8-14 DAY OUTLOOK FOR SEP 08 - 14 2016

TODAY`S WEEK-2 500-HPA HEIGHT SOLUTIONS FROM THE ENSEMBLE MEANS ARE FAIRLY
SIMILAR TO THAT FORECAST FOR THE 6-10 DAY PERIOD OVER MUCH OF THE FORECAST
DOMAIN, BUT WITH SOME EASTWARD PROGRESSION OVER THE NORTHERN CONUS. THE RECENT
DETERMINISTIC RUNS OF THE GFS ARE IN FAIRLY GOOD AGREEMENT WITH THE ECMWF
ENSEMBLE MEAN, AND SO ARE GIVEN SOME WEIGHT IN THE MANUAL BLEND.

ABOVE-NORMAL TEMPERATURES ARE FAVORED ACROSS MUCH OF THE EASTERN AND
SOUTH-CENTRAL CONUS UNDER POSITIVE 500-HPA HEIGHT ANOMALIES. BELOW-NORMAL
TEMPERATURES ARE FAVORED OVER THE INTERIOR NORTHWESTERN CONUS AND NORTHERN
ROCKIES, IN ASSOCIATION WITH A PREDICTED TROUGH. THERE ARE ENHANCED
PROBABILITIES FOR BELOW-NORMAL TEMPERATURES FOR MUCH OF NORTHERN ALASKA
UNDERNEATH CYCLONIC FLOW AND BELOW NORMAL HEIGHTS. ABOVE -NORMAL TEMPERATURES
ARE FAVORED FOR MUCH OF SOUTHERN COASTAL ALASKA IN ASSOCIATION WITH
ABOVE-NORMAL 500-HPA HEIGHTS AND RELATIVELY WARM SSTS.

THE PRECIPITATION OUTLOOK IS DERIVED LARGELY FROM THE CALIBRATED GUIDANCE FROM
THE GEFS AND ECMWF, WITH ABOVE-MEDIAN PRECIPITATION FAVORED MOST STRONGLY OVER
THE UPPER MIDWEST, DOWNSTREAM OF ANOMALOUS TROUGHING FORECAST OVER THE NORTHERN
PLAINS. BELOW-MEDIAN PRECIPITATION IS FAVORED EAST OF THE ANOMALOUS RIDGE AXIS
OVER PARTS OF THE WESTERN CONUS. WITH ANOMALOUS SOUTHERLY FLOW FORECAST OVER
THE EASTERN SEABOARD, A SLIGHT TILT TOWARD ABOVE-MEDIAN PRECIPITATION IS
INDICATED FOR THAT REGION, EXACERBATED BY POTENTIAL INTERACTION WITH TROPICAL
MOISTURE DURING THE PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 30% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 10% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11,
10% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, AND 50% 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 THE VARIOUS MODELS, OFFSET BY UNCERTAINTIES
SURROUNDING THE PRECIPITATION FORECAST OVER THE EASTERN 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
SEPTEMBER 15

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:
19540914 - 19970911 - 19940908 - 20020902 - 19950819


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:
19540913 - 19970911 - 19790908 - 19940908 - 19950819


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

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



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

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