Prognostic Meteorological Discussion
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FXUS06 KWBC 301902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE AUGUST 30 2016

6-10 DAY OUTLOOK FOR SEP 05 - 09 2016

TODAY`S 500-HPA MODEL SOLUTIONS ARE IN GOOD AGREEMENT IN DEPICTING A FAIRLY
AMPLIFIED PATTERN OVER MUCH OF THE FORECAST DOMAIN. TROUGHS ARE FORECAST OVER
THE NORTHERN ROCKIES AND THE ALEUTIANS WHILE RIDGING IS PREDICTED OVER THE
EASTERN THIRD OF THE CONUS. A WEAKNESS IN THE SUBTROPICAL RIDGE IS FORECAST BY
THE GFS- AND ECMWF-BASED SOLUTIONS NEAR THE SOUTHEAST COAST. THE ENSEMBLE
SPAGHETTI CHARTS INDICATE RELATIVELY LOW SPREAD ACROSS MOST OF THE CONUS.
TODAY`S 6-10 DAY 500-HPA HEIGHT BLEND IS WEIGHTED MOST HEAVILY TOWARD THE
ECMWF-BASED SOLUTIONS DUE PRIMARILY TO CONSIDERATIONS OF RECENT SKILL.

ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER MOST OF THE CENTRAL AND EASTERN
CONUS, WITH THE HIGHEST PROBABILITIES INDICATED NEAR THE ANOMALOUS RIDGE AXIS
OVER THE NORTHEASTERN CONUS. HOWEVER, NEAR NORMAL TEMPERATURES ARE FAVORED FOR
PARTS OF THE SOUTHEAST DUE TO A PREDICTED WEAKNESS IN THE SUBTROPICAL RIDGE
OVER THIS 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 PREDICTED CYCLONIC 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 PREDICTED NEAR THE NORTHERN ROCKIES. BELOW MEDIAN PRECIPITATION IS
FAVORED FOR THE NORTHEASTERN CONUS UNDERNEATH PREDICTED RIDGING. NEAR TO BELOW
MEDIAN PRECIPITATION IS MOST LIKELY ACROSS THE SOUTH EASTERN CONUS AS ANY
EFFECTS FROM TROPICAL SYSTEMS ARE EXPECTED BEYOND DAY 10. THERE ARE ENHANCED
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR PARTS OF SOUTHEASTERN TEXAS
DUE TO POTENTIAL INFLUXES OF MOISTURE FROM THE GULF OF MEXICO. ABOVE MEDIAN
PRECIPITATION IS ALSO 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. NEAR TO ABOVE MEDIAN PRECIPITATION IS FAVORED FOR SOUTHERN AND
EASTERN ALASKA IN ASSOCIATION WITH PREDICTED SURFACE LOW PRESSURE. THERE ARE
ENHANCED PROBABILITIES FOR NEAR TO BELOW MEDIAN PRECIPITATION FOR NORTHWESTERN
ALASKA TO THE NORTH OF THE PREDICTED MEAN STORM TRACK.

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, 5% OF
TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 25% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 20% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 5% OF
YESTERDAY`S OPERATIONAL 12Z ECMWF CENTERED ON DAY 7, AND 15% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE VARIOUS MODELS, OFFSET BY UNCERTAINTY IN THE
RECIPITATION OUTLOOK OVER THE SOUTHEAST.



8-14 DAY OUTLOOK FOR SEP 07 - 13 2016

TODAY`S WEEK TWO 500-HPA SOLUTIONS FROM THE ENSEMBLE MEANS ARE FAIRLY SIMILAR
TO THAT PREDICTED FOR THE 6-10 DAY PERIOD OVER MUCH OF THE FORECAST DOMAIN.
TROUGHS ARE PREDICTED OVER THE ALEUTIANS AND THE NORTHWESTERN CONUS WHILE
RIDGING IS FORECAST OVER THE NORTHEAST. THE GREATEST UNCERTAINTY REMAINS THE
POTENTIAL EFFECT OF TROPICAL SYSTEMS EMERGING. TODAY`S WEEK TWO MANUAL HEIGHT
BLEND IS BASED MOSTLY ON THE ENSEMBLE MEAN SOLUTIONS AND THE GREATEST WEIGHTS
WERE GIVEN TO THE EUROPEAN ENSEMBLE MEANS BASED LARGELY ON CONSIDERATIONS OF
RECENT SKILL.

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 NORTHWESTERN CONUS, 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 SSTS.

NEAR TO ABOVE MEDIAN PRECIPITATION IS INDICATED OVER THE SOUTHEAST ASSOCIATED
WITH POTENTIAL INFLUXES OF TROPICAL MOISTURE. ABOVE MEDIAN PRECIPITATION IS
FAVORED FOR THE NORTH-CENTRAL CONUS IN ASSOCIATION WITH A FORECAST TROUGH.
THERE ARE ENHANCED PROBABILITIES FOR NEAR TO BELOW MEDIAN PRECIPITATION THE
SOUTHWESTERN CONUS CONSISTENT WITH GEFS AND ECMWF REFORECAST GUIDANCE. ABOVE
MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF ALASKA UNDERNEATH PREDICTED
CYCLONIC FLOW AND BELOW NORMAL HEIGHTS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 5% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 25% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 40% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 30% OF
TODAY`S 0Z CANADIAN 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: LUKE HE

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:
19970911 - 20020902 - 19950819 - 19800824 - 19540913


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 - 19950819 - 20000809 - 20020901 - 19940908


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 05 - 09 2016

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR SEP 07 - 13 2016

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