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FXUS06 KWBC 271904
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON JULY 27 2015

6-10 DAY OUTLOOK FOR AUG 02 - 06 2015

TODAY`S ENSEMBLE MEAN AND DETERMINISTIC SOLUTIONS ARE IN GOOD AGREEMENT ON THE
FORECAST 500-HPA MEAN CIRCULATION PATTERN OVER NORTH AMERICA AND VICINITY FOR
THE 6-10 DAY PERIOD. THERE IS GOOD CONSENSUS FOR A 500-HPA RIDGE TO BE LOCATED
OVER THE WESTERN CONUS, WITH A DOWNSTREAM TROUGH LOCATED NEAR THE GREAT LAKES.
MOST MODEL SOLUTIONS PREDICT A RIDGE OVER THE BERING SEA AND A TROUGH NEAR THE
GULF OF ALASKA. POSITIVE 500-HPA HEIGHT ANOMALIES ARE GENERALLY FORECAST OVER
ALASKA AND THE WESTERN CONUS WHILE BELOW NORMAL HEIGHTS ARE PREDICTED OVER MUCH
OF THE EASTERN CONUS. TODAY`S OFFICIAL 500-HPA BLEND FAVORS THE ENSEMBLE MEAN
SOLUTIONS AND IS COMPOSED OF SIGNIFICANT CONTRIBUTIONS FROM THE ECMWF, GFS, AND
CANADIAN ENSEMBLE MEANS.

BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE NORTH-CENTRAL CONUS AND THE GREAT
LAKES REGION DUE TO THE TROUGH PREDICTED OVER EASTERN NORTH AMERICA.
CONVERSELY, THERE ARE ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES FOR
MUCH OF THE WESTERN CONUS AND ALASKA UNDERNEATH PREDICTED ABOVE NORMAL HEIGHTS.
ENHANCED PROBABILITIES OF ABOVE NORMAL TEMPERATURES ARE ALSO INDICATED FOR MUCH
OF THE SOUTHERN TIER OF THE CONUS CONSISTENT WITH BIAS CORRECTED TEMPERATURES
FROM THE ECMWF ENSEMBLES AND WITH GEFS REFORECAST GUIDANCE.

GEFS REFORECAST GUIDANCE AND PRECIPITATION ESTIMATES FROM THE ECMWF ENSEMBLES
INDICATE FAVORABLE CONDITIONS FOR ABOVE-MEDIAN PRECIPITATION FOR MUCH OF THE
INTERIOR WEST INCLUDING THE GREAT BASIN, CENTRAL ROCKIES, AND PARTS OF THE
SOUTHWEST. ABOVE MEDIAN PRECIPITATION IS ALSO FAVORED FOR PARTS OF THE GREAT
LAKES REGION EXTENDING TO NORTHERN NEW ENGLAND IN ASSOCIATION WITH THE TROUGH
PREDICTED OVER EASTERN NORTH AMERICA. BELOW MEDIAN PRECIPITATION IS FAVORED
BEHIND THE TROUGH AXIS FOR PARTS OF THE NORTHERN PLAINS. PROBABILITIES FOR
ABOVE-MEDIAN PRECIPITATION ARE ENHANCED FOR PARTS OF THE SOUTHEASTERN CONUS IN
ASSOCIATION WITH A PREDICTED FRONTAL BOUNDARY EARLY IN THE PERIOD. BELOW MEDIAN
PRECIPITATION IS FAVORED FOR PARTS OF THE SOUTHERN PLAINS AND SOUTHERN
MISSISSIPPI VALLEY CONSISTENT WITH GEFS REFORECAST GUIDANCE, NAEFS GUIDANCE,
AND PRECIPITATION ESTIMATES FROM THE ECMWF ENSEMBLE MEMBERS. ENHANCED
PROBABILITIES OF BELOW MEDIAN PRECIPITATION ARE ALSO INDICATED FOR MUCH OF
ALASKA AND THE PACIFIC NORTHWEST UNDERNEATH PREDICTED ABOVE NORMAL 500-HPA
HEIGHTS.

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 6Z GFS CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 10% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 5% OF
YESTERDAY`S OPERATIONAL 12Z ECMWF CENTERED ON DAY 7, 20% OF TODAY`S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 5% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 7


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

8-14 DAY OUTLOOK FOR AUG 04 - 10 2015

TODAY`S MODEL FORECASTS FOR THE 8-14 DAY 500-HPA CIRCULATION ARE QUITE SIMILAR
TO AND REFLECT A SLIGHT PROGRESSION OF THE OVERALL PATTERN OF THE 6-10 DAY
MEAN. A MEAN TROUGH IS PREDICTED OVER EASTERN NORTH AMERICA CENTERED NEAR THE
EASTERN GREAT LAKES WHILE A RIDGE CENTERED NEAR THE ROCKIES IS FORECAST OVER
THE WESTERN CONUS. IN ADDITION, POSITIVE HEIGHT ANOMALIES CONTINUE TO BE
FORECAST FOR MOST OF ALASKA. THE WEEK TWO MANUAL 500-HPA BLEND IS COMPOSED
PRIMARILY OF THE ENSEMBLE MEAN SOLUTIONS AND IS BASED, IN PART, ON
CONSIDERATIONS OF RECENT SKILL AND ON ANALOG CORRELATIONS, WHICH MEASURE HOW
CLOSELY THE FORECAST PATTERN MATCHES CASES THAT HAVE OCCURRED IN THE PAST.

THE PERSISTENT TROUGH OVER THE EASTERN CONUS ELEVATE CHANCES FOR BELOW-NORMAL
TEMPERATURES FOR A LARGE PORTION OF THE NORTH-CENTRAL AND NORTHEASTERN CONUS.
FARTHER TO THE SOUTH, ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE
SOUTHEASTERN CONUS CONSISTENT WITH GEFS REFORECAST GUIDANCE AND BIAS CORRECTED
TEMPERATURES FROM THE ECMWF ENSEMBLE MEMBERS. CHANCES ARE ENHANCED FOR
ABOVE-NORMAL TEMPERATURES IN MUCH OF THE WEST UNDER THE EXPECTED 500-HPA RIDGE.
ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED FOR MUCH OF ALASKA UNDERNEATH
PREDICTED ABOVE NORMAL 500-HPA HEIGHTS.

GEFS REFORECAST GUIDANCE AND PRECIPITATION ESTIMATES FROM THE ECMWF ENSEMBLE
MEMBERS CONTINUE TO FAVOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE INTERIOR
WEST. NEAR TO ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE EASTERN
SEABOARD IN ASSOCIATION WITH THE TROUGH PREDICTED OVER EASTERN NORTH AMERICA.
HOWEVER, FORECAST PROBABILITIES ARE LOW FOR THIS REGION DUE TO CONFLICTING
GUIDANCE BETWEEN THE WETTER NAEFS AND THE DRIER SOLUTIONS FROM THE GEFS
REFORECAST AND ECMWF PRECIPITATION ESTIMATES. TOOLS ARE IN BETTER AGREEMENT
OVER THE SOUTHERN PLAINS, WHERE BELOW MEDIAN PRECIPITATION IS FAVORED. BELOW
MEDIAN PRECIPITATION IS ALSO FAVORED FOR PARTS OF THE UPPER MISSISSIPPI VALLEY
AND WESTERN GREAT LAKES BEHIND THE TROUGH AXIS PREDICTED OVER EASTERN NORTH
AMERICA. TOOLS ARE IN GOOD AGREEMENT IN FAVORING BELOW MEDIAN PRECIPITATION FOR
MUCH OF ALASKA UNDERNEATH PREDICTED ABOVE NORMAL 500-HPA HEIGHTS.



THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 15% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 5% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 25% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 10% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 10% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED
ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO
RELATIVELY GOOD AGREEMENT AMONG MODELS OFFSET BY DISAGREEMENTS AMONG THE
SURFACE TOOLS (PARTICULARLY FOR PRECIPITATION).

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
AUGUST 20

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:
19640801 - 19960718 - 19540722 - 19810801 - 19630719


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:
19540723 - 19640801 - 19960717 - 19810801 - 20010731


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 02 - 06 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 04 - 10 2015

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