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FXUS06 KWBC 301901
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED JULY 30 2014

6-10 DAY OUTLOOK FOR AUG 05 - 09 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 PREDICTIONS FOR 500-HPA HEIGHTS ARE VERY SIMILAR TO
YESTERDAY`S PREDICTIONS, SO THERE ARE RELATIVELY MINOR CHANGES IN THE
RESPECTIVE SURFACE FORECASTS.  ALASKA REMAINS THE MOST DIFFICULT REGION OF THE
COUNTRY TO FORECAST 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 CENTRAL CONUS AND
ABOVE-NORMAL TEMPERATURES FAVORED FOR MUCH OF THE WEST. THE AXIS OF THE EASTERN
TROUGH IS SLIGHTLY FARTHER WEST TODAY THAN IN YESTERDAYS SOLUTION, INCREASING
THE CHANCES OF NEAR NORMAL TEMPERATURES ALONG THE EAST COAST, AND ENHANCING
CHANCES FOR ABOVE-NORMAL TEMPERATURES NEAR FLORIDA. 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.  TOOLS SUGGEST A RATHER WIDE AREA OF SLIGHTLY ENHANCED PRECIPITATION
PROBABILITIES, SUGGESTING A CONSIDERABLE SPREAD IN THE LOCATION AND INTENSITY
OF RAINFALL AMOUNTS. NAEFS AND THE GEFS REFORECAST TOOL CONTINUES TO SHOW
ENHANCED CHANCES OF ABOVE-MEDIAN PRECIPITATION AMOUNTS IN PARTS OF THE
INTERMOUNTAIN WEST, WITH BELOW-MEDIAN PRECIPITATION FAVORED NEAR THE PACIFIC
NORTHWEST COAST. CONSISTENT WITH YESTERDAY`S OUTLOOK, TODAY`S TOOLS SHOW
INCREASING CHANCES FOR BELOW-MEDIAN PRECIPITATION IN WESTERN PARTS OF THE
REGION INFLUENCED BY THE SOUTHWEST MONSOON. THE CHANCES FOR ABOVE-MEDIAN
PRECIPITATION ARE ENHANCED FOR SOUTHERN 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 PRECIPITATION TOOLS SUGGEST
DRIER CONDITIONS IN THE ALASKAN PANHANDLE THAN INDICATED YESTERDAY, HOWEVER,
PROBABILITIES HAVE BEEN REVISED TOWARD HIGHER PRECIPITATION AMOUNTS IN THE
NORTHERN PANHANDLE BECAUSE OF UNCERTAINTY IN THE FORECAST OF THE UPPER-LEVEL
CIRCULATION IN THE REGION.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 30 PERCENT OF TODAY`S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...40 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 0Z ECMWF 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 07 - 13 2014

THE ANOMALY PATTERN FOR THE FORECAST 500-HPA HEIGHTS OVER THE CONUS AND
SOUTHERN CANADA IS 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, CANADIAN) OR SOUTHWEST (GEFS) 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. THE NAEFS AND GEFS REFORECAST TOOL INDICATIONS FOR BELOW-MEDIAN
PRECIPITATION IN THE SOUTHWEST CONTINUE TO SUGGEST A WEAK SOUTHWESTERN MONSOON
OVER WESTERN PARTS OF THE MONSOON REGION.

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:
19670711 - 20080808 - 19620721 - 19650727 - 19560716


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:
19670711 - 19620722 - 20080808 - 20040804 - 19600709


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 05 - 09 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   N    N     WYOMING     B    A
UTAH        B    A     ARIZONA     A    B     COLORADO    B    A
NEW MEXICO  N    A     N DAKOTA    B    B     S DAKOTA    B    N
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     B    A     S TEXAS     A    N     W TEXAS     N    A
MINNESOTA   B    B     IOWA        B    N     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   B    N     WISCONSIN   B    B
ILLINOIS    B    A     MISSISSIPPI B    A     MICHIGAN    B    A
INDIANA     B    A     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        B    A     NEW JERSEY  N    A     W VIRGINIA  B    A
MARYLAND    N    A     DELAWARE    N    A     VIRGINIA    N    A
N CAROLINA  N    A     S CAROLINA  A    A     GEORGIA     A    A
FL PNHDL    A    N     FL PENIN    A    N     AK N SLOPE  A    B
AK ALEUTIAN A    N     AK WESTERN  A    B     AK INT BSN  A    N
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    N    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 07 - 13 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       N    A     NEVADA      A    A
W MONTANA   N    A     E MONTANA   N    A     WYOMING     B    A
UTAH        N    A     ARIZONA     A    B     COLORADO    B    A
NEW MEXICO  N    A     N DAKOTA    B    B     S DAKOTA    B    N
NEBRASKA    B    N     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     N    A     S TEXAS     A    N     W TEXAS     B    A
MINNESOTA   B    B     IOWA        B    N     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   N    N     WISCONSIN   B    B
ILLINOIS    B    A     MISSISSIPPI B    A     MICHIGAN    B    B
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A
TENNESSEE   B    A     ALABAMA     N    A     NEW YORK    N    A
VERMONT     N    A     NEW HAMP    N    A     MAINE       N    A
MASS        N    A     CONN        N    A     RHODE IS    N    A
PENN        B    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    N
FL PNHDL    A    N     FL PENIN    A    B     AK N SLOPE  A    B
AK ALEUTIAN A    N     AK WESTERN  A    B     AK INT BSN  A    B
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    A    B

                           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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