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FXUS06 KWBC 311925
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU JULY 31 2014

6-10 DAY OUTLOOK FOR AUG 06 - 10 2014

THERE IS FAIR AGREEMENT AMONG TODAY`S MODEL SOLUTIONS FOR THE MEAN 500-HPA
HEIGHTS OVER NORTH AMERICA AND VICINITY DURING THE 6-10 DAY PERIOD. THE MODELS
AGREE ON A RELATIVELY LOW AMPLITUDE FLOW PATTERN, WITH 500-HPA HEIGHTS OVER
MOST OF THE CONUS SLIGHTLY BELOW AVERAGE, WHILE HEIGHTS JUST NORTH OF THE
U.S.-CANADIAN BORDER ARE PREDICTED TO BE NEAR TO ABOVE AVERAGE. MOST MODELS
AGREE ON SUBSTANTIAL NEGATIVE 500-HPA HEIGHT ANOMALIES IN A FAIRLY DEEP TROUGH
OVER THE GULF OF ALASKA. THE ECMWF CONTINUES TO PREDICT AN ENHANCED TROUGH OVER
THE EAST-CENTRAL CONUS, AND WAS WEIGHTED SLIGHTLY HIGHER IN TODAY`S BLEND THAN
THE GEFS OR CANADIAN MODELS IN VIEW OF ITS AGREEMENT WITH TELECONNECTIONS ON
THE TROUGH OVER THE GULF OF ALASKA. ALASKA REMAINS THE MOST DIFFICULT REGION OF
THE COUNTRY TO FORECAST FOR DUE TO A RELATIVELY COMPLEX 500-HPA FLOW PATTERN
FORECAST OVER THE STATE.

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 NEAR THE WEST COAST. UPPER-LEVEL HEIGHT
ANOMALIES OVER THE SOUTHEAST ARE PREDICTED TO EDGE INTO POSITIVE VALUES,
INCREASING THE CHANCES OF ABOVE-NORMAL TEMPERATURES FOR PARTS OF THE
SOUTHEASTERN CONUS AND 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 AND
THE POSSIBILITY OF COOLER TEMPERATURES ASSOCIATED WITH 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 AND EASTERN CONUS.  TOOLS SUGGEST A RATHER WIDE AREA
OF SLIGHTLY ENHANCED PRECIPITATION PROBABILITIES, SUGGESTING A CONSIDERABLE
SPREAD IN THE LOCATION AND INTENSITY OF RAINFALL AMOUNTS AMONG ENSEMBLE
SOLUTIONS. THE 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.  TODAY`S
TOOLS SHOW AN 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 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: ABOUT AVERAGE, 3 OUT OF 5, WITH
RELATIVELY WEAK ANOMALIES IN 500-HPA HEIGHTS PREDICTED FOR THE PERIOD.

8-14 DAY OUTLOOK FOR AUG 08 - 14 2014

THE FORECAST 500-HPA HEIGHTS OVER THE CONUS AND SOUTHERN CANADA ARE PREDICTED
TO BE 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 OF THE STATE. THE
SPREAD AMONG SOLUTIONS, HOWEVER, IS FAIRLY LARGE, WITH AN INCREASING PERCENTAGE
OF GEFS ENSEMBLES HINTING AT AN AMPLIFIED TROUGH OVER THE WESTERN CONUS.
TODAY`S 12Z GFS DETERMINISTIC RUN PREDICTS A CHANGE IN THE RECENTLY OBSERVED
500-HPA CIRCULATION, WITH A FAIRLY DEEP TROUGH IN THE WEST AND RIDGE OVER THE
EASTERN CONUS. THIS SOLUTION REMAINS AN OUTLIER, BUT HIGHLIGHTS THE UNCERTAINTY
IN TODAY`S PREDICTION.

TOOLS FOR SURFACE TEMPERATURE AND PRECIPITATION ANOMALIES CONTINUE TO SHOW A
CONSISTENT SIGNAL FOR BELOW NORMAL TEMPERATURES IN THE CENTRAL PART OF THE
COUNTRY, WITH ABOVE NORMAL TEMPERATURES FAVORED ALONG THE WEST COAST, THE
SOUTHERN U.S. BORDER, AND PARTS OF THE SOUTHEAST. NEAR NORMAL TEMPERATURES ARE
SLIGHTLY FAVORED FOR MOST OF THE NORTHEASTERN CONUS WITH CONSIDERABLE
UNCERTAINTY AND A POSSIBLE TRANSITION FROM COOL CONDITIONS EARLY IN THE PERIOD
TO WARMER CONDITIONS LATER IN THE PERIOD.

THE NAEFS AND GEFS REFORECAST TOOL INDICATIONS FOR BELOW-MEDIAN PRECIPITATION
IN THE SOUTHWEST CONTINUE TO SUGGEST A WEAK SOUTHWESTERN MONSOON. TOOLS FOR
PRECIPITATION ARE IN FAIRLY GOOD AGREEMENT HIGHLIGHTING A PATTERN THAT IS QUITE
SIMILAR TO THE 6-10 DAY OUTLOOK.

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: BELOW AVERAGE, 2 OUT OF 5,DUE
TO AN EXPECTED PROGRESSION TO A LOW-AMPLITUDE UPPER LEVEL FLOW PATTERN OVER
MUCH OF NORTH AMERICA, AND CONSIDERABLE SPREAD AMONG ENSEMBLE SOLUTIONS.

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:
19670712 - 19620723 - 20080808 - 19560716 - 19650727


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 - 19620723 - 20080808 - 20040804 - 19620718


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 06 - 10 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   N    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     B    A
MINNESOTA   B    B     IOWA        B    N     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   B    N     WISCONSIN   B    B
ILLINOIS    B    A     MISSISSIPPI B    N     MICHIGAN    B    N
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A
TENNESSEE   B    A     ALABAMA     N    N     NEW YORK    B    A
VERMONT     B    N     NEW HAMP    B    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    N     VIRGINIA    N    A
N CAROLINA  N    N     S CAROLINA  A    N     GEORGIA     A    N
FL PNHDL    A    B     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    N    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 08 - 14 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      N    N
W MONTANA   N    A     E MONTANA   B    A     WYOMING     B    A
UTAH        B    N     ARIZONA     A    B     COLORADO    B    N
NEW MEXICO  N    B     N DAKOTA    B    N     S DAKOTA    B    A
NEBRASKA    B    A     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     N    N     S TEXAS     A    B     W TEXAS     A    N
MINNESOTA   B    N     IOWA        B    A     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   N    N     WISCONSIN   N    N
ILLINOIS    B    A     MISSISSIPPI N    A     MICHIGAN    N    B
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    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        N    A     NEW JERSEY  N    A     W VIRGINIA  N    A
MARYLAND    N    A     DELAWARE    N    A     VIRGINIA    N    A
N CAROLINA  N    A     S CAROLINA  A    A     GEORGIA     A    N
FL PNHDL    A    N     FL PENIN    A    B     AK N SLOPE  A    B
AK ALEUTIAN A    A     AK WESTERN  A    N     AK INT BSN  A    N
AK S INT    A    A     AK SO COAST A    A     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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