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FXUS06 KWBC 251901
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI JULY 25 2014

6-10 DAY OUTLOOK FOR JUL 31 - AUG 04, 2014

TODAY`S OUTLOOK REMAINS LITTLE CHANGED FROM YESTERDAY`S AS THE VARIOUS GLOBAL
ENSEMBLE MEANS AND DETERMINISTIC RUNS REMAIN IN GOOD AGREEMENT. THE TREND OVER
THE PAST COUPLE OF DAYS THAT CONTINUES TO THIS POINT, IS A GRADUAL
DEAMPLIFICATION OF THE FORECAST TROUGH OVER THE EASTERN CONUS AS UPPER-LEVEL
HEIGHTS BUILD TO THE NORTH AND THE MEAN TROUGH BEGINS TO RESEMBLE A CUTOFF LOW.
INDEED, STEPPING THROUGH THE 0Z ECWMF DETERMINISTIC RUN (WHICH IS
CHARACTERISTIC OF THE GLOBAL MODEL CONSENSUS) REVEALS THAT A WEAK CUTOFF IS
FAIRLY LIKELY AT SYNOPTIC TIMESCALES OVER THE LOWER AND MIDDLE MISSISSIPPI
VALLEY. THIS IS EXPECTED TO HAVE THE MOST IMPACT ON DAYTIME MAXIMUM
TEMPERATURES OVER THE SOUTH-CENTRAL CONUS GIVEN THE PRECIPITATION AND CLOUD
COVER THAT ARE TYPICALLY ASSOCIATED WITH THESE TYPES OF UPPER-LEVEL SYSTEMS.

THE DYNAMICAL MODEL PRECIPITATION TOOLS ARE IN GOOD AGREEMENT ON THE GENERAL
STRUCTURE OF ANOMALOUS RAINFALL AT THIS LEAD. WITH THE MANUAL BLEND DEPICTING
THE 500-HPA TROUGH AXIS EXTENDING FROM LAKE MICHIGAN SOUTH-SOUTHWESTWARD TO THE
LOWER MISSISSIPPI VALLEY, THE TYPICAL RESPONSE VIA SYNOPTIC QUASI-GEOSTROPHIC
ARGUMENTS IS DEPICTED WITH ENHANCED PROBABILITIES OF ABOVE-MEDIAN
(BELOW-MEDIAN) RAINFALL EAST (WEST) OF THE TROUGH AXIS. THIS RELATIONSHIP
BECOMES WEAKER AS THE TROUGH BECOMES MORE CUTOFF AND THUS PROBABILITIES ARE NOT
EXCEEDINGLY HIGH. THE ENHANCED PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION
ALONG THE GULF COAST EXTENDING WESTWARD TO THE INTERIOR SOUTHWEST ARE A RESULT
OF THE STALLED BAROCLINIC ZONE FORECAST OVER THAT REGION. A MORE CURIOUS TASK
IS EXPLAINING THE TENDENCY TOWARD WETTER-THAN-NORMAL CONDITIONS DEPICTED OVER
PARTS OF THE INTERMOUNTAIN WEST AND NORTHERN ROCKIES. THIS SEEMS TO BE IN
RESPONSE TO LOWER-THAN-NORMAL SURFACE PRESSURES AND ABOVE-NORMAL UPPER-LEVEL
HEIGHTS, WHICH FAVORS ABOVE-NORMAL TEMPERATURES AND ENHANCED DIURNAL
CONVECTION. PROBABILITIES IN THIS REGION ARE TEMPERED BY THE LESS ENTHUSIASTIC
ECWMF ENSEMBLE MEAN.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY`S OPERATIONAL 0Z
GFS CENTERED ON DAY 8...10 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON
DAY 8...20 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...20
PERCENT OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8...AND 40 PERCENT OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN 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 EXCELLENT AGREEMENT AMONG TODAY`S MODELS AND TOOLS.

8-14 DAY OUTLOOK FOR AUG 02 - 08 2014

THE SPATIAL CONTINUITY OF THE OFFICIAL 500-HPA HEIGHT MANUAL BLEND FROM THE
6-10 DAY PERIOD TO WEEK-2 IS REMARKABLE, ALBEIT AT REDUCED AMPLITUDE. THIS
STEMS LARGELY FROM RAPIDLY INCREASING ENSEMBLE SPREAD, WHICH NECESSARILY
REDUCES THE AMPLITUDE OF THE VARIOUS ENSEMBLE MEANS. THE RECENT DETERMINISTIC
RUNS OF THE GFS ARE IN GOOD AGREEMENT DEPICTING THE HIGH-OVER-LOW HEIGHT
ANOMALY PATTERN DEPICTED IN THE MANUAL BLEND OVER THE CONUS, THOUGH AT MUCH
HIGHER AMPLITUDE. GIVEN THE TIME OF YEAR, CARE MUST BE TAKEN NOT TO
OVEREMPHASIZE THE DETERMINISTIC RUNS EVEN CONSIDERING THEIR GOOD CONTINUITY.

THE RESULTING SURFACE OUTLOOKS ARE VERY SIMILAR TO THOSE FOR THE 6-10 PERIOD,
THOUGH WITH LOWER PROBABILITIES TO REFLECT INCREASING UNCERTAINTY. THERE IS
LITTLE EVIDENCE OF A DRAMATIC PATTERN CHANGE THROUGH THE END OF WEEK-2.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 5 PERCENT OF TODAY`S OPERATIONAL
0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED
ON DAY 11...25 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND
60 PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11.

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

FORECASTER: STEPHEN BAXTER

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:
20000725 - 19810801 - 19690805 - 19690723 - 19630720


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:
19690806 - 19690722 - 19690801 - 20000724 - 19810801


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 31 - AUG 04, 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 02 - 08 2014

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