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FXUS06 KWBC 231905
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED JULY 23 2014

6-10 DAY OUTLOOK FOR JUL 29 - AUG 02, 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 GOOD AGREEMENT ON WHAT SHOULD BE ANOTHER
IMPRESSIVELY COOL SUMMER PERIOD OVER THE EAST-CENTRAL CONUS. TODAY`S OFFICIAL
500-HPA HEIGHT MANUAL BLEND FOR THE 6-10 DAY PERIOD IS QUITE SIMILAR TO
YESTERDAY`S, THOUGH THERE IS A SUBTLE RETROGRESSION OF THE HIGH-AMPLITUDE
FEATURES ACROSS MUCH OF NORTH AMERICA AND THE WESTERN ATLANTIC.

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 EVEN HIGHER THAN
IN YESTERDAY`S OUTLOOK, WITH THE ANOMALOUSLY COOL AIR MASS FORECAST TO SETTLE
FARTHER SOUTH AND WEST. ANOMALOUS RIDGING COMBINED WITH ANOMALOUS OFFSHORE
WINDS STRONGLY FAVOR ABOVE-NORMAL TEMPERATURES FOR THE WESTERN CONUS.
ABOVE-NORMAL HEIGHTS FAVOR NEAR- TO ABOVE-NORMAL TEMPERATURES FOR THE
ALEUTIANS, SOUTHERN ALASKA, AND THE ALASKAN PANHANDLE. BELOW-NORMAL
TEMPERATURES ARE FAVORED IN NORTHEASTERN ALASKA WHERE HIGH PRESSURE AND
ANOMALOUS NORTHERLY FLOW FAVOR BELOW-NORMAL TEMPERATURES.

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 AND SOUTHERN APPALACHIANS IN THE POST-FRONTAL REGION WHERE SURFACE
RIDGING IS FORECAST TO NOSE IN FROM THE NORTHWEST. THE FRONT FORECAST TO EXTEND
FROM NEAR THE EASTERN SEABOARD TURNING WESTWARD ALONG THE GULF COAST WILL BE A
FOCAL POINT FOR PRECIPITATION. THIS FAVORS NEAR- TO ABOVE-MEDIAN PRECIPITATION
FOR PARTS OF THE EASTERN U.S. EXTENDING WESTWARD TO THE SOUTHERN PLAINS AND
PARTS OF THE SOUTHWEST. 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 NORTHERLY FLOW AT MID LEVELS EAST
OF THE AMPLIFIED RIDGE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15 PERCENT OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8...10 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 JUL 31 - AUG 06, 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 THE
NEAR-NORMAL 500-HPA HEIGHTS FORECAST A RESULT OF LARGE ENSEMBLE SPREAD.

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...10 PERCENT OF TODAY`S 6Z 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: 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 - 20010731 - 19670720 - 19820720 - 20050717


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:
19670720 - 20010731 - 19820720 - 19810730 - 20050716


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 29 - AUG 02, 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     OREGON      A    N     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       A    N     NEVADA      A    A
W MONTANA   A    B     E MONTANA   A    B     WYOMING     N    N
UTAH        A    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   B    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    B     OHIO        B    N     KENTUCKY    B    B
TENNESSEE   B    B     ALABAMA     B    N     NEW YORK    B    N
VERMONT     B    N     NEW HAMP    B    N     MAINE       N    N
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    A     GEORGIA     B    A
FL PNHDL    B    A     FL PENIN    N    A     AK N SLOPE  B    B
AK ALEUTIAN A    B     AK WESTERN  A    B     AK INT BSN  N    B
AK S INT    A    B     AK SO COAST A    B     AK PNHDL    N    A



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 31 - AUG 06, 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    B     OREGON      A    N     NRN CALIF   A    N
SRN CALIF   A    N     IDAHO       A    N     NEVADA      A    N
W MONTANA   A    N     E MONTANA   A    N     WYOMING     N    N
UTAH        A    N     ARIZONA     A    A     COLORADO    B    N
NEW MEXICO  B    A     N DAKOTA    A    B     S DAKOTA    N    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    N     MISSOURI    B    N
ARKANSAS    B    A     LOUISIANA   B    A     WISCONSIN   B    N
ILLINOIS    B    A     MISSISSIPPI B    A     MICHIGAN    B    N
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A
TENNESSEE   B    A     ALABAMA     B    A     NEW YORK    N    A
VERMONT     N    N     NEW HAMP    N    N     MAINE       A    B
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  N    B
AK ALEUTIAN A    N     AK WESTERN  A    B     AK INT BSN  N    B
AK S INT    A    B     AK SO COAST A    B     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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