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FXUS06 KWBC 071901
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 07 2015

6-10 DAY OUTLOOK FOR JUL 13 - 17 2015

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA MEAN
CIRCULATION PATTERN ANTICIPATED OVER MOST OF THE NORTH AMERICA DOMAIN FOR THE
6-10 DAY PERIOD, BUT THE DETERMINISTIC 00Z AND 06Z GFS RUNS PREDICT A SOMEWHAT
DEAMPLIFIED FLOW PATTERN. THE ENSEMBLE MEANS DEPICT A MEAN TROUGH NEAR THE WEST
COAST OF NORTH AMERICA, WITH ITS ASSOCIATED CLOSED VORTEX CENTERED OVER THE
EASTERN BERING SEA, AND ANOTHER TROUGH CENTERED NEAR THE APPALACHIANS AND
EASTERN SEABOARD. THE ENSEMBLE MEANS ALSO FORECAST AN AMPLIFIED RIDGE OVER THE
INTERIOR OF WESTERN NORTH AMERICA, WITH THE RIDGE AXIS IN THE APPROXIMATE
VICINITY OF THE ROCKIES. IN CONTRAST WITH THIS LATTER CIRCULATION FEATURE, THE
DETERMINISTIC 00Z AND 06Z GFS SOLUTIONS PREDICT A FAIRLY FLAT RIDGE OVER MUCH
OF THE WESTERN CONUS AND AN AMPLIFIED RIDGE OVER WESTERN CANADA, SEPARATED BY
FAST WESTERLY FLOW NEAR AND ALONG THE U.S.-CANADIAN BORDER. THE DETERMINISTIC
GFS RUNS ALSO FAVOR A SOMEWHAT FASTER EASTERN CONUS TROUGH, WITH THE AXIS OVER,
OR EAST OF, THE ATLANTIC COAST. THE VARIOUS ENSEMBLE SPAGHETTI MAPS (5820 METER
HEIGHTS) INDICATE LOW TO MODERATE SPREAD/DISPERSION ACROSS THE LOWER 48 STATES.

ABOVE-NORMAL TEMPERATURES ARE FAVORED ACROSS APPROXIMATELY THE SOUTHEASTERN
QUARTER OF THE CONTIGUOUS U.S., THE PLAINS, THE NORTHERN ROCKIES, COASTAL PARTS
OF CALIFORNIA, AND NORTHERN AND FAR WESTERN ALASKA. THIS IS GENERALLY
CONSISTENT WITH THE PREDICTED 500-HPA HEIGHT AND ANOMALY PATTERN, THE GEFS
CALIBRATED AND UNCALIBRATED RE-FORECAST TEMPERATURES, NAEFS BIAS-CORRECTED
TEMPERATURES, AND THE AUTOMATIC BLENDED TEMPERATURES. BELOW-NORMAL TEMPERATURES
ARE FAVORED ACROSS MUCH OF THE SOUTHERN COAST OF ALASKA, IN A SWATH FROM
WESTERN OREGON SOUTHEASTWARD ACROSS NEVADA TO THE FOUR CORNERS AREA, THE GREAT
LAKES REGION, AND THE NORTHEAST. THIS IS BASED ON THE SAME TOOLS NOTED ABOVE.

ABOVE-MEDIAN PRECIPITATION IS GENERALLY INDICATED AHEAD OF THE TROUGH PREDICTED
NEAR THE WEST COAST OF NORTH AMERICA, AND ALSO WITH THE TROUGH PREDICTED IN THE
EASTERN CONUS. BELOW-MEDIAN PRECIPITATION IS FAVORED ACROSS THE CENTRAL AND
SOUTHERN PLAINS, THE LOWER MISSISSIPPI VALLEY, THE FLORIDA PENINSULA, AND THE
NORTH SLOPE OF ALASKA. THE PRECIPITATION OUTLOOK IS BASED ON THE GEFS
CALIBRATED AND UNCALIBRATED RE-FORECAST PRECIPITATION, NAEFS PRECIPITATION,
AUTO-BLEND PRECIPITATION, AND IS GENERALLY CONSISTENT WITH THE ANTICIPATED
500-HPA HEIGHT AND ANOMALY MAP.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 10% OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8, 25% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY
8, 10% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND 15% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG THE ENSEMBLE MEANS, BUT OFFSET SOMEWHAT BY THE
UNCERTAINTIES INTRODUCED BY THE DETERMINISTIC 00Z AND 06Z GFS SOLUTIONS.

8-14 DAY OUTLOOK FOR JUL 15 - 21 2015

THE WEEK-2 ENSEMBLE MEAN PREDICTIONS OF THE MID-TROPOSPHERIC CIRCULATION
PATTERN ACROSS NORTH AMERICA ARE IN GOOD AGREEMENT, AND CONSISTENT WITH THE
EXPECTED MEAN CIRCULATION PATTERN ANTICIPATED FOR THE 6-10 DAY PERIOD. THE 06Z
GFS ENSEMBLE MEAN AND TODAY`S GFS SUPER-ENSEMBLE MEAN DISTINCTLY SHOW SPLIT
FLOW CENTERED OVER WESTERN CANADA, WITH A RIDGE TO THE NORTH AND A TROUGH TO
THE SOUTH. THE DETERMINISTIC 00Z AND 06Z GFS SOLUTIONS ANTICIPATE A FEW
DIFFERENCES WITH THE ENSEMBLE MEAN FORECASTS. FIRST, THEY BOTH FORECAST A WEAK
TROUGH OVER THE PACIFIC NORTHWEST, AND SECOND, THE 00Z GFS RUN PREDICTS A MUCH
WEAKER TROUGH IN THE EASTERN CONUS. ENSEMBLE SPREAD IS GENERALLY CONSIDERED TO
BE MODERATE TODAY ACROSS MOST OF THE CONUS, AND MODERATE TO HIGH OFF THE
PACIFIC NORTHWEST COAST IN REGARD TO THE PREDICTED TROUGH.

THE SURFACE TEMPERATURE AND PRECIPITATION OUTLOOKS FOR WEEK-2 ARE GENERALLY
SIMILAR TO THOSE FOR THE 6-10 DAY PERIOD, THOUGH THERE ARE SOME DIFFERENCES. A
SLIGHT, OVERALL WARMING IS ANTICIPATED ACROSS THE WEST, AND THE PROBABILITY FOR
BELOW-NORMAL TEMPERATURES IS INCREASED TO 50 PERCENT OVER PARTS OF THE
NORTHEAST. THE PRECIPITATION OUTLOOK IS MUCH MORE UNCERTAIN, HENCE THE EXPECTED
BROAD COVERAGE OF NEAR-MEDIAN RAINFALL. THE SAME TOOLS THAT WERE USED FOR THE
6-10 DAY PRECIPITATION OUTLOOK WERE ALSO USED FOR THE WEEK-2 PRECIPITATION
OUTLOOK. VERY SIGNIFICANT DIFFERENCES EXIST AMONG TOOLS, AND A WEIGHTED AVERAGE
USING VARIOUS TOOLS PRODUCES FORECAST PROBABILITIES CLOSE TO CLIMATOLOGICAL
AVERAGES.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 11, 25% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 25% 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 GOOD ENSEMBLE MEAN AGREEMENT, BUT OFFSET BY BOTH CONFLICTING AND VERY WEAK
PRECIPITATION SIGNALS.

FORECASTER: ANTHONY ARTUSA

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
JULY 16

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:
19520711 - 19990712 - 19870628 - 19950629 - 19510627


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:
19520711 - 19990712 - 19870628 - 19950629 - 19510626


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 13 - 17 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 15 - 21 2015

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