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FXUS06 KWBC 291935
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 29 2016

6-10 DAY OUTLOOK FOR SEP 04 - 08 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 WESTERN ALASKA WHILE RIDGING IS PREDICTED OVER THE
NORTHEASTERN CONUS. SUBTROPICAL RIDGING IS FORECAST OVER PARTS OF THE
SOUTH-CENTRAL CONUS. A WEAKNESS IN THE SUBTROPICAL RIDGE IS FORECAST BY THE
GFS- AND ECMWF-BASED SOLUTIONS OVER PARTS OF THE SOUTHEAST. 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 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
MUCH OF THE EASTERN CONUS UNDERNEATH PREDICTED RIDGING. HOWEVER, NEAR TO ABOVE
MEDIAN PRECIPITATION IS INDICATED FOR PARTS OF THE SOUTHEAST IN ASSOCIATION
WITH A PREDICTED WEAKNESS IN THE SUBTROPICAL RIDGE AND POTENTIAL INFLUXES OF
TROPICAL MOISTURE. 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 PARTS OF THE SOUTHERN HIGH PLAINS AND SOUTHWEST 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 ALASKA IN ASSOCIATION WITH PREDICTED
SURFACE LOW PRESSURE. THERE ARE ENHANCED PROBABILITIES FOR NEAR TO BELOW MEDIAN
PRECIPITATION FOR CENTRAL AND NORTHERN 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: AVERAGE, 3 OUT OF 5, DUE TO FAIRLY
GOOD AGREEMENT AMONG THE VARIOUS MODELS, OFFSET BY UNCERTAINTY IN THE
PRECIPITATION OUTLOOK OVER THE SOUTHEAST.


8-14 DAY OUTLOOK FOR SEP 06 - 12 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 WESTERN ALASKA AND THE NORTHWESTERN CONUS WHILE
RIDGING IS FORECAST OVER THE NORTHEAST. THE GREATEST DISAGREEMENT AMONG THE
MODELS IS OVER THE SOUTHEAST DUE TO UNCERTAINTIES SURROUNDING A FORECAST
WEAKNESS IN THE SUBTROPICAL RIDGE AND THE POTENTIAL FOR TROPICAL SYSTEMS TO
AFFECT THIS REGION. DISAGREEMENTS ARE ALSO APPARENT AMONG THE DETERMINISTIC GFS
SOLUTIONS AS RUN TO RUN CONTINUITY IS POOR OVER MUCH OF THE FORECAST DOMAIN.
DUE TO THESE UNCERTAINTIES, TODAY`S WEEK TWO MANUAL HEIGHT BLEND IS BASED
MOSTLY ON THE ENSEMBLE MEAN SOLUTIONS. THE GREATEST WEIGHTS WERE GIVEN TO THE
GFS ENSEMBLE MEANS DUE, IN PART, TO RELATIVELY GOOD ANALOG CORRELATIONS, WHICH
MEASURE HOW CLOSELY THE FORECAST PATTERN MATCHES CASES THAT HAVE OCCURRED IN
THE PAST.

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 A LARGE REGION OF THE WESTERN 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.

FORECAST RIDGING LEADS TO ENHANCED PROBABILITIES FOR BELOW MEDIAN PRECIPITATION
FOR PARTS OF THE EASTERN CONUS. HOWEVER, FAVORED NEAR MEDIAN PRECIPITATION IS
INDICATED ALONG THE SOUTHERN ATLANTIC AND GULF COASTS DUE TO UNCERTAINTIES
ASSOCIATED WITH POTENTIAL INFLUXES OF TROPICAL MOISTURE. ABOVE MEDIAN
PRECIPITATION IS FAVORED FOR THE NORTHWESTERN AND NORTH-CENTRAL CONUS IN
ASSOCIATION WITH A FORECAST TROUGH. THERE ARE ENHANCED PROBABILITIES FOR ABOVE
MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHWEST AND FOR BELOW MEDIAN
PRECIPITATION FOR PARTS OF THE CENTRAL ROCKIES CONSISTENT WITH GEFS 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: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 30% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 25% OF TODAY`S
0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 5% OF YESTERDAY`S 12Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO POOR RUN TO RUN CONTINUITY AMONG THE DETERMINISTIC GFS SOLUTIONS AS WELL AS
UNCERTAINTIES SURROUNDING THE PRECIPITATION FORECAST OVER THE SOUTHEASTERN
CONUS.


FORECASTER: SCOTT HANDEL

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:
19800824 - 20020902 - 19970911 - 19590824 - 19740810


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:
19800824 - 20040903 - 19930808 - 19560903 - 20000809


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

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    A     OREGON      B    A     NRN CALIF   B    N
SRN CALIF   B    N     IDAHO       B    A     NEVADA      B    B
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    B     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   A    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    B     LOUISIANA   A    N     WISCONSIN   A    A
ILLINOIS    A    N     MISSISSIPPI A    B     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    N     GEORGIA     N    B
FL PNHDL    N    N     FL PENIN    N    N     AK N SLOPE  B    N
AK ALEUTIAN A    N     AK WESTERN  A    B     AK INT BSN  B    B
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    A    A



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

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    A     OREGON      B    A     NRN CALIF   N    N
SRN CALIF   N    N     IDAHO       B    A     NEVADA      B    N
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    A
UTAH        B    N     ARIZONA     B    N     COLORADO    N    B
NEW MEXICO  N    N     N DAKOTA    N    A     S DAKOTA    N    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    B     LOUISIANA   A    N     WISCONSIN   A    A
ILLINOIS    A    A     MISSISSIPPI A    B     MICHIGAN    A    A
INDIANA     A    N     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    N     VIRGINIA    A    B
N CAROLINA  A    N     S CAROLINA  A    N     GEORGIA     A    N
FL PNHDL    A    N     FL PENIN    A    N     AK N SLOPE  B    A
AK ALEUTIAN A    N     AK WESTERN  N    N     AK INT BSN  B    A
AK S INT    N    A     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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