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FXUS06 KWBC 061919
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 06 2015

6-10 DAY OUTLOOK FOR JUL 12 - 16 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 RUNS PREDICT SIGNIFICANT DIFFERENCES.
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 OVER EASTERN NORTH AMERICA. AN AMPLIFIED RIDGE IS
FORECAST OVER THE INTERIOR OF WESTERN NORTH AMERICA, WITH THE RIDGE AXIS IN THE
APPROXIMATE VICINITY OF THE ROCKIES. THE PREDICTED SUBTROPICAL RIDGE EXTENDS
ACROSS MOST OF THE SUBTROPICAL PORTIONS OF THE PACIFIC AND ATLANTIC BASINS, AND
THE SOUTHERN CONUS. THE DETERMINISTIC RUNS DIFFER FROM THE ENSEMBLE MEANS IN
SEVERAL WAYS. THE SINGLE 00Z ECMWF SOLUTION DEPICTS TWO TROUGH AXES IN THE
EASTERN CONUS. THE FIRST IS NEAR THE ATLANTIC COAST, AND THE SECOND EXTENDS
ACROSS THE GREAT LAKES, AND THE MIDDLE AND LOWER MISSISSIPPI VALLEY. THE 00Z
DETERMINISTIC GFS SOLUTION PREDICTS AN AMPLIFIED TROUGH-RIDGE-TROUGH PATTERN
ENCOMPASSING THE REGION FROM THE FAR EASTERN PACIFIC TO THE EASTERN CONUS. THE
06Z DETERMINISTIC GFS FORECASTS SOME DISRUPTION IN THE RIDGE EXPECTED ACROSS
WEST-CENTRAL NORTH AMERICA, WITH MUCH FLATTER FLOW ACROSS THE SOUTHERN CANADIAN
PRAIRIES AND NORTHERN US GREAT PLAINS. THIS MODEL SOLUTION ALSO DEPICTS THE
EASTWARD ADVECTION OF THE TROUGH EXPECTED OVER EASTERN CANADA, THOUGH KEEPS THE
CONUS PORTION OF THE TROUGH IN PLACE OVER THE U.S. EAST COAST STATES.

THE 06Z GFS AND 00Z CANADIAN ENSEMBLE SPAGHETTI MAPS INDICATE MODERATE SPREAD
ASSOCIATED WITH THE EXPECTED TROUGH JUST OFF THE WEST COAST OF NORTH AMERICA,
WITH SIGNIFICANTLY LESS DISPERSION BETWEEN ENSEMBLE MEMBERS (IMPROVED
AGREEMENT) WITH THE PREDICTED WEST-CENTRAL CONUS RIDGE AND EASTERN CONUS
TROUGH. THE 00Z ECMWF ENSEMBLE SPAGHETTI MAPS INDICATE MODERATE SPREAD WITH THE
WEST COAST TROUGH, WITH ONLY SLIGHTLY LESS DISPERSION FOR THE DOWNSTREAM
RIDGE-TROUGH COUPLET.

ABOVE-NORMAL TEMPERATURES ARE FAVORED ACROSS APPROXIMATELY THE SOUTHEASTERN
QUARTER OF THE CONTIGUOUS U.S., THE PLAINS, THE NORTHERN ROCKIES, THE PACIFIC
NORTHWEST, 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, CENTRAL AND SOUTH-CENTRAL PORTIONS
OF BOTH THE INTER-MOUNTAIN REGION AND ROCKIES, AND THE GREAT LAKES REGION. 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 MOST OF THE CENTRAL
THIRD OF THE CONUS, 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 MODELS.

8-14 DAY OUTLOOK FOR JUL 14 - 20 2015

THE WEEK-2 ENSEMBLE MEAN PREDICTIONS OF THE MID-TROPOSPHERIC CIRCULATION
PATTERN ACROSS NORTH AMERICA ARE IN GOOD AGREEMENT, AND CONSISTENT WITH THE
PREDICTED MEAN CIRCULATION PATTERN ANTICIPATED FOR THE 6-10 DAY PERIOD. RECENT
RUNS OF THE DETERMINISTIC GFS (00Z, 06Z, AND 12Z), HOWEVER, SHOW VERY
SIGNIFICANT DIFFERENCES WITH EACH OTHER AND WITH OTHER MODEL SOLUTIONS. THE 00Z
GFS SOLUTION PREDICTS A PATTERN THAT IS VERY SIMILAR TO THAT OF THE 6-10 DAY
PERIOD. THE 06Z GFS, HOWEVER, IS COMPLETELY OUT OF PHASE, FORECASTING A TROUGH
OVER THE WESTERN CONUS, AND A RIDGE OVER THE CENTRAL AND EASTERN CONUS. THE 12Z
GFS FLATTENS THE FLOW ACROSS THE WESTERN CONUS, AND REINTRODUCES A TROUGH OVER
THE EASTERN CONUS. THE 500-HPA MANUAL BLEND IS THEREFORE BASED ALMOST ENTIRELY
ON THE ENSEMBLE MEAN FORECASTS. ENSEMBLE SPREAD IS CONSIDERED MODERATE ACROSS
MOST OF THE CONUS TODAY, AND HIGH OFF THE PACIFIC NORTHWEST COAST IN REGARD TO
THE PREDICTED TROUGH.

THE SURFACE TEMPERATURE AND PRECIPITATION OUTLOOKS FOR WEEK-2 ARE SIMILAR TO
THOSE FOR THE 6-10 DAY PERIOD, THOUGH THERE ARE SOME DIFFERENCES. THE MORE
NOTICEABLE CHANGES INCLUDE THE ANTICIPATION OF A MORE EXTENSIVE AREA OF
BELOW-NORMAL TEMPERATURES FROM THE MIDDLE MISSISSIPPI VALLEY EAST-NORTHEASTWARD
ACROSS THE GREAT LAKES AND NORTHEAST, AND A CORRESPONDING SOUTHWARD
DISPLACEMENT OF PREDICTED ABOVE-NORMAL TEMPERATURES ACROSS THE DEEP SOUTH. THE
PRECIPITATION OUTLOOK IS A BIT MORE UNCERTAIN, AS INDICATED BY LARGER
VARIATIONS AMONG THE DIFFERENT TOOLS. THE EXPECTED AREA OF ABOVE-MEDIAN
PRECIPITATION ACROSS THE NORTHEASTERN QUARTER OF THE CONUS IS IN GENERAL
AGREEMENT WITH THE IDEA OF A WESTWARD SHIFTED TROUGH FROM THE OHIO VALLEY TO
THE MIDWEST.

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, 15% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, 25% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% 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,
PRIMARILY BECAUSE OF THE LARGE UNCERTAINTIES ASSOCIATED WITH THE LAST 3 RUNS OF
THE DETERMINISTIC GFS MODEL, AND SIGNIFICANT DIFFERENCES IN THE PRECIPITATION
TOOLS.

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 - 19950629 - 19870627 - 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 - 19870627 - 19950629 - 19510626


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 12 - 16 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    A     OREGON      A    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    B
NEBRASKA    A    B     KANSAS      A    B     OKLAHOMA    A    B
N TEXAS     A    B     S TEXAS     A    B     W TEXAS     A    B
MINNESOTA   A    N     IOWA        N    B     MISSOURI    A    B
ARKANSAS    A    B     LOUISIANA   A    B     WISCONSIN   B    A
ILLINOIS    N    N     MISSISSIPPI A    B     MICHIGAN    B    A
INDIANA     N    A     OHIO        N    A     KENTUCKY    A    N
TENNESSEE   A    N     ALABAMA     A    N     NEW YORK    B    A
VERMONT     N    A     NEW HAMP    N    A     MAINE       N    N
MASS        N    A     CONN        N    A     RHODE IS    N    A
PENN        N    A     NEW JERSEY  N    A     W VIRGINIA  A    A
MARYLAND    A    A     DELAWARE    A    A     VIRGINIA    A    A
N CAROLINA  A    A     S CAROLINA  A    N     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 14 - 20 2015

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

                           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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