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FXUS06 KWBC 291939
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE JULY 29 2014

6-10 DAY OUTLOOK FOR AUG 04 - 08 2014

TODAY`S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 6-10 DAY MEAN 500-HPA
HEIGHTS OVER NORTH AMERICA AND VICINITY. THE MODELS PERSIST THE LONG-WAVE
TROUGH OVER THE EAST-CENTRAL CONUS, AND CONTINUE TO INDICATE A RIDGE OVER THE
WEST. TODAY`S MODELS PREDICT CONSIDERABLY LESS AMPLITUDE IN THE 500-HPA
FEATURES THAN IN YESTERDAY`S RUNS. THIS IS CONSISTENT WITH THE EXPECTED
LESSENING OF THE AMPLITUDE OF THE UPPER-LEVEL CIRCULATION PATTERN SUGGESTED BY
YESTERDAY`S 8-14 DAY OUTLOOK. WITH LOWER AMPLITUDE, THE CONFIDENCE IN TODAY`S
FORECAST IS SOMEWHAT LOWER THAN YESTERDAY`S OUTLOOK, HOWEVER, BOTH THE
TEMPERATURE AND PRECIPITATION TOOLS REMAIN IN GOOD AGREEMENT ON THE FORECAST
ANOMALY PATTERN FOR THE CONUS. TOOLS ARE IN LESS GOOD AGREEMENT FOR ALASKA,
WHERE DAY-TO-DAY CONSISTENCY IS QUITE LOW. THIS IS DUE TO A RELATIVELY COMPLEX
500-HPA FLOW PATTERN FORECAST OVER THE STATE, WITH A FAIRLY DEEP TROUGH
PREDICTED JUST TO THE SOUTH OF THE STATE, WHILE A FAIRLY SHARP RIDGE IS
FORECAST JUST OFF THE WESTERN ALASKAN COAST.

THE 6-10 DAY TEMPERATURE OUTLOOK REMAINS SIMILAR TO YESTERDAY`S, WITH CHANCES
OF BELOW-NORMAL TEMPERATURES ENHANCED FOR MUCH OF THE EASTERN AND CENTRAL CONUS
AND ABOVE-NORMAL TEMPERATURES FAVORED FOR MUCH OF THE WEST. PROBABILITIES ARE
HIGHEST NEAR AND TO THE NORTH OF AN EXPECTED FRONTAL BOUNDARY, WHERE
PRECIPITATION MAY HELP SUPPRESS DAYTIME TEMPERATURES.  A FAIRLY STRONG GRADIENT
IN TEMPERATURE ANOMALIES IS EXPECTED JUST WEST OF THE ROCKIES, LEADING TO HIGH
UNCERTAINTY IN TEMPERATURES FOR THE INTERMOUNTAIN WEST.  ABOVE-NORMAL
TEMPERATURES ARE FAVORED FOR WESTERN ALASKA, ALTHOUGH TEMPERATURES IN THE
EASTERN PART OF THE STATE ARE MUCH LESS CERTAIN DUE TO THE TROUGH FORECAST TO
BE OVER THE GULF OF ALASKA. NEAR-NORMAL TEMPERATURES ARE FAVORED IN PARTS OF
SOUTHEASTERN ALASKA, IN ASSOCIATION WITH EXPECTED PRECIPITATION.

THE PRECIPITATION OUTLOOK FAVORS ABOVE-MEDIAN RAINFALL AMOUNTS ALONG AN
EXPECTED MEAN FRONTAL BOUNDARY THAT EXTENDS FROM THE CENTRAL ROCKIES TO THE
MIDDLE MISSISSIPPI VALLEY TO THE SOUTHEAST CONUS, AND THEN ALONG THE EASTERN
SEABOARD. TODAY`S MODELS SUGGEST THE ZONE OF ENHANCED FRONTAL PRECIPITATION TO
BE FARTHER NORTH THAN YESTERDAY`S RUNS OVER THE CENTRAL CONUS, LEADING TO
ENHANCED CHANCES FOR BELOW MEDIAN PRECIPITATION FOR SOUTHERN TEXAS. NAEFS AND
THE GEFS REFORECAST TOOL SHOW ENHANCED CHANCES OF ABOVE-MEDIAN PRECIPITATION
AMOUNTS IN PARTS OF THE INTERMOUNTAIN WEST, WITH BELOW-MEDIAN PRECIPITATION
FAVORED NEAR THE PACIFIC NORTHWEST COAST.  ABOVE-MEDIAN PRECIPITATION IS
EXPECTED FOR SOUTHEASTERN ALASKA, AHEAD OF AN EXPECTED TROUGH OVER THE GULF OF
ALASKA, WITH THE RELATIVELY DRY CONDITIONS FAVORED FOR THE WESTERN AND CENTRAL
PARTS OF THE STATE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 40 PERCENT OF TODAY`S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...30 PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE
MEAN CENTERED ON DAY 8...AND 30 PERCENT OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 8.

MODEL OF THE DAY: TODAY`S 6Z GEFS ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG TODAY`S MODELS AND TOOLS.

8-14 DAY OUTLOOK FOR AUG 06 - 12 2014

THE ANOMALY PATTERN FOR THE FORECAST 500-HPA HEIGHTS OVER THE CONUS AND
SOUTHERN CANADA REMAINS SIMILAR TO THE 6-10 DAY MEAN ALTHOUGH THE MAGNITUDE OF
THE ANOMALIES ARE QUITE SMALL. THE ENSEMBLE MEANS FROM THE ECMWF, GEFS, AND
CANADIAN MODELS ALL SHOW AN EASTERN TROUGH THAT IS SLIGHTLY DEEPER, AND FARTHER
WEST THAN NORMAL. ELSEWHERE OVER MOST OF NORTH AMERICA, THE ENSEMBLE MEANS
PREDICT THE 500-HPA HEIGHTS TO BE VERY CLOSE TO THE LONG TERM AVERAGES. THE
ONLY SUBSTANTIAL ANOMALIES EVIDENT ON THE 8-14 DAY ENSEMBLE MEANS ARE
ABOVE-NORMAL 500-HPA HEIGHTS OVER ALASKA, WITH BELOW NORMAL HEIGHTS PREDICTED
IN A TROUGH TO THE SOUTH (ECMWF) OR SOUTHWEST (GEFS, CANADIAN MODELS) OF THE
STATE.

IN SPITE OF THE FORECAST FOR WEAK UPPER-LEVEL ANOMALIES, THE SURFACE
TEMPERATURE AND PRECIPITATION ANOMALIES ARE REMARKABLY CONSISTENT AMONG THE
TOOLS. THIS IS LIKELY DUE TO MODEL CONSENSUS EARLY IN THE PERIOD, SINCE THE
TEMPERATURE AND PRECIPITATION OUTLOOKS FOR 8-14 DAYS ARE SIMILAR TO THE 6-10
DAY OUTLOOK.  CONDITIONS LATE IN THE WEEK TWO PERIOD ARE LIKELY TO BE
UNCERTAIN.  A NOTABLE FEATURE IN TODAY`S PRECIPITATION FORECAST IS THE
APPEARANCE OF ELEVATED PROBABILITIES FOR BELOW-MEDIAN PRECIPITATION IN THE
SOUTHWEST IN THE NAEFS AND GEFS REFORECASTS. THIS SUGGESTS THAT CONDITIONS MAY
BECOME LESS FAVORABLE FOR THE SOUTHWEST MONSOON, WITHIN THE 8-14 DAY PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 30 PERCENT OF TODAY`S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11...40 PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE
MEAN CENTERED ON DAY 11...AND 30 PERCENT 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, WITH
GOOD AGREEMENT AMONG THE MODELS AND TOOLS OFFSET BY AN EXPECTED PROGRESSION TO
A LOW-AMPLITUDE UPPER LEVEL FLOW PATTERN OVER MUCH OF NORTH AMERICA.

FORECASTER: DAVE UNGER

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
AUGUST 21

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:
19620721 - 20080808 - 19670711 - 19650726 - 19690801


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:
19620722 - 19670711 - 20080807 - 19600709 - 19630810


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 04 - 08 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 06 - 12 2014

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