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FXUS06 KWBC 241901
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 24 2014

6-10 DAY OUTLOOK FOR JUL 30 - AUG 03, 2014

TODAY`S MODELS REMAIN IN EXCELLENT AGREEMENT WITH RESPECT TO THE FORECAST
CIRCULATION OVER NORTH AMERICA. CONFIDENCE ALSO REMAINS HIGH AS THE VARIOUS
DYNAMICAL AND STATISTICAL TOOLS ARE IN EXCEPTIONAL AGREEMENT IN DEPICTING A
MUCH COOLER-THAN-NORMAL PERIOD ACROSS THE EAST-CENTRAL CONUS. TODAY`S OFFICIAL
500-HPA HEIGHT MANUAL BLEND FOR THE 6-10 DAY PERIOD IS QUITE SIMILAR TO
YESTERDAY`S, AND AS A RESULT THE REASONING BEHIND THE SURFACE OUTLOOKS IS
UNCHANGED.

A HIGH-AMPLITUDE TROUGH PREDICTED OVER THE EASTERN CONUS FAVORS ANOMALOUS
NORTHERLY WINDS AND BELOW-NORMAL TEMPERATURES OVER MUCH OF THE EASTERN U.S. THE
EXTENT OF PROBABILITIES FAVORING BELOW-NORMAL TEMPERATURES IS LARGELY
UNCHANGED, WITH ANOMALOUSLY COOL CONDITIONS EXPECTED OVER MUCH OF THE CONUS
EAST OF THE ROCKIES. ANOMALOUS RIDGING AND OFFSHORE WINDS STRONGLY FAVOR
ABOVE-NORMAL TEMPERATURES FOR THE WESTERN CONUS. ABOVE-NORMAL HEIGHTS FAVOR
NEAR- TO ABOVE-NORMAL TEMPERATURES FOR THE ALEUTIANS AND WESTERN ALASKA.

BELOW-MEDIAN PRECIPITATION IS FAVORED NEAR AND DOWNSTREAM OF THE AMPLIFIED
RIDGE FORECAST OVER WESTERN NORTH AMERICA. THIS REGION EXTENDS ALL THE WAY TO
THE CENTRAL APPALACHIANS IN THE POST-FRONTAL REGION WHERE SURFACE RIDGING IS
FORECAST TO NOSE IN FROM THE NORTHWEST. PROBABILITIES FOR ABOVE-MEDIAN
PRECIPITATION ARE AGAIN THE HIGHEST OVER THE SOUTHWEST, WHERE THE STALLED
FRONTAL SYSTEM WILL FOCUS PRECIPITATION FOR AN EXTENDED PERIOD OF TIME.
BELOW-MEDIAN PRECIPITATION IS FAVORED FOR WESTERN ALASKA DUE TO ANOMALOUS
NORTHEASTERLY FLOW AT MID LEVELS EAST OF THE AMPLIFIED RIDGE, WHILE
ABOVE-MEDIAN PRECIPITATION IS FAVORED ACROSS PARTS OF SOUTHERN ALASKA AND THE
PANHANDLE ASSOCIATED WITH A TROUGH FORECAST OVER THE GULF OF ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8...15 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON
DAY 8...15 PERCENT OF TODAY`S 6Z 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 01 - 07 2014

THE FORECAST CIRCULATION FOR WEEK-2 IS EXPECTED TO BE VERY SIMILAR TO THE 6-10
DAY PERIOD, THOUGH SIGNIFICANTLY LESS AMPLIFIED. THE MEAN TROUGH POSITION OVER
THE EASTERN CONUS IS FORECAST TO SHIFT WEST SLIGHTLY FROM THE 6-10 DAY PERIOD.
THE TEMPERATURE OUTLOOK IS SIMILAR TO THAT IN THE 6-10 DAY PERIOD, THOUGH
PROBABILITIES ARE SLIGHTLY LOWER AND THE PROBABILITIES FOR BELOW-NORMAL
TEMPERATURES ARE SHIFTED SOUTH AS HIGHER HEIGHTS ARE FORECAST TO BUILD ACROSS
THE NORTHERN TIER OF THE CONUS. UNCERTAINTY IS SUBSTANTIALLY HIGHER ACROSS THE
WESTERN THIRD OF THE CONUS COMPARED TO THE 6-10 DAY PERIOD, WITH NEAR-NORMAL
500-HPA HEIGHTS FORECAST, A RESULT OF LARGE ENSEMBLE SPREAD.

RETURN FLOW AROUND SURFACE HIGH PRESSURE ENHANCES PROBABILITIES OF ABOVE-MEDIAN
PRECIPITATION ACROSS PARTS OF THE INTERMOUNTAIN WEST AND ROCKIES, WHILE THE
POSITION OF THE MEAN TROUGH OVER THE MISSISSIPPI VALLEY FAVORS ABOVE-MEDIAN
PRECIPITATION ACROSS PARTS OF THE EAST AND BELOW-MEDIAN PRECIPITATION OVER
PARTS OF THE NORTHERN PLAINS AND MIDWEST.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10 PERCENT OF TODAY`S
OPERATIONAL 0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON
DAY 11...15 PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 55
PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO GOOD AGREEMENT AMONG THE MODELS AND TOOLS, OFFSET BY THE FACT THAT THE
PATTERN IS PREDICTED TO BE LESS AMPLIFIED THAN IN THE 6-10 DAY PERIOD.

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:
19810731 - 20000725 - 20010801 - 19670720 - 19690804


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:
19690802 - 19810801 - 19630724 - 19790704 - 19670720


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 30 - AUG 03, 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 01 - 07 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    A
W MONTANA   A    A     E MONTANA   A    N     WYOMING     B    A
UTAH        B    A     ARIZONA     N    A     COLORADO    B    A
NEW MEXICO  B    A     N DAKOTA    A    B     S DAKOTA    B    B
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    B     MISSOURI    B    B
ARKANSAS    B    N     LOUISIANA   B    A     WISCONSIN   B    B
ILLINOIS    B    B     MISSISSIPPI B    A     MICHIGAN    B    N
INDIANA     B    N     OHIO        B    A     KENTUCKY    B    A
TENNESSEE   B    A     ALABAMA     B    A     NEW YORK    N    N
VERMONT     A    N     NEW HAMP    A    N     MAINE       A    N
MASS        A    N     CONN        N    N     RHODE IS    A    N
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  N    B
AK ALEUTIAN A    B     AK WESTERN  A    B     AK INT BSN  A    B
AK S INT    A    N     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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