Prognostic Meteorological Discussion
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FXUS06 KWBC 101929
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 10 2014

6-10 DAY OUTLOOK FOR JUL 16 - 20 2014

TODAY`S OFFICIAL 500-HPA HEIGHT MANUAL BLEND FEATURES A VERY HIGH-AMPLITUDE
PATTERN FOR THIS TIME OF YEAR. A STRONG RIDGE IS FORECAST OVER THE PACIFIC
NORTHWEST, WESTERN CANADA, AND EASTERN ALASKA WITH DEEP TROUGHS FORECAST SOUTH
OF THE ALEUTIANS AND OVER THE EASTERN CONUS. TODAYS ENSEMBLE MEANS ARE IN GOOD
AGREEMENT ON THIS PATTERN, AND THE 6Z GFS AND 0Z ECWMF DETERMINISTIC RUNS
EXHIBIT GOOD AGREEMENT AND EXCEPTIONAL AMPLITUDE. SINCE THIS FORECAST PATTERN
HAS REMAINED VERY AMPLIFIED AND CONSISTENT AMONG ALL THE ENSEMBLES AND MOST OF
THE DETERMINISTIC RUNS, AND THE FACT THAT THIS FORECAST IS FOR THE RELATIVELY
SHORT LEAD OF 6-10 DAYS, THIS FORECAST IS MADE WITH FAIRLY HIGH CONFIDENCE.

A DEEP TROUGH OVER THE EASTERN CONUS FAVORS BELOW NORMAL TEMPERATURES IN THIS
REGION WHERE THE MEAN AIR MASS IS LIKELY TO BE ONE OF CANADIAN ORIGIN.
SOUTHERLY FLOW IS EXPECTED TO TRANSPORT WARM TROPICAL AIR INTO PARTS OF
SOUTHERN TEXAS AND FLORIDA, FAVORING ABOVE NORMAL TEMPERATURES THERE. VERY HIGH
PROBABILITIES OF ABOVE-NORMAL TEMPERATURES ARE DEPICTED FOR PARTS OF THE
WESTERN CONUS, NEAR THE AXIS OF THE AMPLIFIED RIDGE.

THE RIDGE IN THE PACIFIC NORTHWEST IS EXPECTED TO PREVENT STORM SYSTEMS FROM
COMING ONSHORE, FAVORING NEAR TO BELOW MEDIAN PRECIPITATION FROM THE ALASKAN
PANHANDLE, INTO THE PACIFIC NORTHWEST. THE CHANCE FOR ABOVE-MEDIAN
PRECIPITATION IS INCREASED IN THE FOUR CORNERS REGION DUE TO MONSOON ACTIVITY,
WHILE THE FRONTAL BOUNDARY ACROSS THE CENTRAL PLAINS INTO THE SOUTHEAST AND
MID-ATLANTIC IS EXPECTED TO BE A FOCAL POINT FOR ABOVE MEDIAN PRECIPITATION IN
THOSE AREAS. THIS FRONTAL BOUNDARY IS NOT EXPECTED TO REACH SOUTHERN TEXAS,
RESULTING IN BELOW-MEDIAN PRECIPITATION FOR THAT REGION. AS THE FRONTAL
BOUNDARY IS EXPECTED TO BE DISPLACED FURTHER SOUTH THAN NORMAL, DRIER AIR IS
EXPECTED FROM THE NORTHERN PLAINS THROUGH THE NORTHEAST, FAVORING BELOW-MEDIAN
PRECIPITATION IN THOSE REGIONS. SEVERAL AREAS OF SURFACE LOW PRESSURE ARE
EXPECTED TO INFLUENCE PARTS OF NORTHERN ALASKA AND THE ALEUTIANS, INCREASING
THE LIKELIHOOD OF ABOVE-MEDIAN PRECIPITATION IN THOSE AREAS.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 25 PERCENT OF TODAY`S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY`S OPERATIONAL 6Z GFS
CENTERED ON DAY 8...35 PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 8...AND 20 PERCENT OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8.

MODEL OF THE DAY: TODAY`S 0Z ECMWF ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: WELL ABOVE AVERAGE, 5 OUT OF 5,
DUE TO VERY GOOD AGREEMENT AMONG MODELS AND TOOLS IN A FORECAST HIGH-AMPLITUDE
PATTERN.

8-14 DAY OUTLOOK FOR JUL 18 - 24 2014

THE FORECAST CIRCULATION FOR WEEK-2 RETAINS A SIMILAR SPATIAL STRUCTURE TO THAT
FORECAST FOR THE 6-10 DAY PERIOD, BUT WITH DRASTICALLY REDUCED AMPLITUDE AS THE
VARIOUS ENSEMBLE MEMBERS DIVERGE QUICKLY BEYOND DAY 10. THIS INCREASED
UNCERTAINTY REDUCES CONFIDENCE IN THE FORECAST, THOUGH THIS IS EXPECTED FOR
THIS TIME OF YEAR, WHEN PREDICTABILITY IS ON THE LOW SIDE. THE TEMPERATURE
ANOMALY OUTLOOK IS VERY SIMILAR TO THAT IN THE 6-10 DAY PERIOD, THOUGH WITH
MUCH LOWER PROBABILITIES. THE PRECIPITATION ANOMALY OUTLOOK IN WEEK-2 IS ALSO
IS VERY SIMILAR TO THAT FORECAST FOR THE 6-10 DAY PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 40 PERCENT OF TODAY`S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF TODAY`S OPERATIONAL 6Z GFS
CENTERED ON DAY 11...AND 40 PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: NEAR AVERAGE, 3 OUT OF 5, DUE
TO FAIRLY GOOD AGREEMENT AMONG MODELS AND FORECAST TOOLS, OFFSET BY LARGE MODEL
SPREAD, A FORECAST LOW-AMPLITUDE PATTERN, AND SOME DISAGREEMENT AMONG THE
TOOLS.

FORECASTER: MIKE CHARLES

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 17

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:
20060723 - 19980724 - 19710720 - 19960709 - 19700622


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:
19700622 - 19960712 - 19980723 - 19870629 - 19850619


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 16 - 20 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    B     NEVADA      A    A
W MONTANA   A    B     E MONTANA   N    B     WYOMING     B    N
UTAH        A    A     ARIZONA     A    A     COLORADO    B    A
NEW MEXICO  N    A     N DAKOTA    B    B     S DAKOTA    B    B
NEBRASKA    B    N     KANSAS      B    A     OKLAHOMA    B    A
N TEXAS     N    A     S TEXAS     N    N     W TEXAS     N    A
MINNESOTA   B    B     IOWA        B    B     MISSOURI    B    A
ARKANSAS    B    A     LOUISIANA   N    A     WISCONSIN   B    B
ILLINOIS    B    N     MISSISSIPPI B    A     MICHIGAN    B    B
INDIANA     B    N     OHIO        B    N     KENTUCKY    B    A
TENNESSEE   B    A     ALABAMA     B    A     NEW YORK    B    B
VERMONT     B    B     NEW HAMP    B    B     MAINE       N    B
MASS        B    B     CONN        B    B     RHODE IS    B    B
PENN        B    N     NEW JERSEY  B    N     W VIRGINIA  B    A
MARYLAND    B    A     DELAWARE    B    A     VIRGINIA    B    A
N CAROLINA  B    A     S CAROLINA  B    A     GEORGIA     B    A
FL PNHDL    N    A     FL PENIN    A    N     AK N SLOPE  B    A
AK ALEUTIAN A    A     AK WESTERN  N    N     AK INT BSN  B    A
AK S INT    N    B     AK SO COAST N    B     AK PNHDL    A    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 18 - 24 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    N     NEVADA      A    A
W MONTANA   A    N     E MONTANA   N    N     WYOMING     N    N
UTAH        A    A     ARIZONA     A    A     COLORADO    B    A
NEW MEXICO  B    A     N DAKOTA    N    N     S DAKOTA    N    N
NEBRASKA    B    N     KANSAS      B    N     OKLAHOMA    B    A
N TEXAS     B    A     S TEXAS     N    N     W TEXAS     B    A
MINNESOTA   N    B     IOWA        B    N     MISSOURI    B    N
ARKANSAS    B    A     LOUISIANA   N    N     WISCONSIN   B    B
ILLINOIS    B    N     MISSISSIPPI B    A     MICHIGAN    B    B
INDIANA     B    N     OHIO        B    N     KENTUCKY    B    A
TENNESSEE   B    A     ALABAMA     B    A     NEW YORK    N    B
VERMONT     N    B     NEW HAMP    N    B     MAINE       N    B
MASS        N    B     CONN        N    B     RHODE IS    N    B
PENN        B    B     NEW JERSEY  N    B     W VIRGINIA  B    N
MARYLAND    B    N     DELAWARE    N    N     VIRGINIA    B    A
N CAROLINA  N    A     S CAROLINA  N    A     GEORGIA     N    A
FL PNHDL    A    A     FL PENIN    A    N     AK N SLOPE  B    A
AK ALEUTIAN A    N     AK WESTERN  N    N     AK INT BSN  B    B
AK S INT    N    B     AK SO COAST N    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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