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FXUS06 KWBC 301925
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON MARCH 30 2015

6-10 DAY OUTLOOK FOR APR 05 - 09 2015

TODAY`S SOLUTIONS FOR THE 500-HPA HEIGHTS ARE IN FAIR AGREEMENT AMONG THE
VARIOUS MODEL ENSEMBLE MEANS. MODELS PREDICT A TROUGH OVER OR JUST OFF THE WEST
COAST OF THE CONUS WITH A WEAK RIDGE OVER THE EAST-CENTRAL CONUS NEAR THE
MISSISSIPPI VALLEY. A DEEP TROUGH IS FORECAST OFF THE EAST COAST OF THE CONUS.
THERE HAS BEEN SOME INCONSISTENCY IN RECENT GFS HIGH-RESOLUTION FORECASTS ON
THE UPPER-LEVEL FEATURES OVER THE CONUS. THE MANUAL BLEND EMPHASIZES THE ECMWF
AND CANADIAN ENSEMBLE MEAN SOLUTION, WHICH INDICATES A DEEPER WEST COAST
TROUGH, AND HIGHER AMPLITUDE EASTERN RIDGE THAN THE GFS ENSEMBLES, AND IS IN
AGREEMENT WITH TODAY`S 12Z GFS.

THE FORECAST RIDGE OVER THE EASTERN CONUS ELEVATES THE CHANCES FOR ABOVE-NORMAL
TEMPERATURES FOR MUCH OF THE EASTERN AND CENTRAL CONUS. BELOW-NORMAL
TEMPERATURES ARE EXPECTED TO CONTINUE IN THE NORTHEASTERN CONUS CLOSE TO THE
TROUGH EXPECTED OFF THE EAST COAST, ALTHOUGH CONFIDENCE IS FAIRLY LOW
CONSIDERING THE SPREAD OF SOLUTIONS OF THE STRENGTH OF THE UPSTREAM RIDGE.
BELOW-NORMAL TEMPERATURES ARE FAVORED FOR MUCH OF THE WEST NEAR THE EXPECTED
WEST-COAST TROUGH. ALASKAN TEMPERATURES ARE QUITE UNCERTAIN DUE TO A RELATIVELY
HIGH SPREAD OF 500-HPA SOLUTIONS, WITH NEAR-NORMAL TEMPERATURES SLIGHTLY
FAVORED IN THE NORTHERN AND CENTRAL PARTS OF THE STATE, AND ABOVE-NORMAL
TEMPERATURES NEAR THE GULF OF ALASKA WHERE SEA SURFACE TEMPERATURES REMAIN
ABOVE NORMAL.

THE OUTLOOK FAVORS ABOVE-MEDIAN PRECIPITATION AMOUNTS FOR MUCH OF THE EASTERN
CONUS IN EXPECTED SOUTHWESTERLY FLOW AHEAD OF THE WESTERN TROUGH, WHICH WILL
ALLOW NORTHWARD TRANSPORT OF MOISTURE FROM THE GULF OF MEXICO. THE CHANCES OF
ABOVE-MEDIAN PRECIPITATION ARE ELEVATED FOR THE PACIFIC NORTHWEST NEAR THE
EXPECTED WESTERN TROUGH. BELOW-MEDIAN PRECIPITATION IS FAVORED FOR MUCH OF THE
SOUTHWEST, SOUTHERN AND CENTRAL ROCKIES AND PARTS OF THE CENTRAL HIGH PLAINS TO
THE SOUTH OF THE EXPECTED PACIFIC STORM TRACK. MOST TOOLS FAVOR ABOVE-MEDIAN
PRECIPITATION FOR SOUTHERN AND CENTRAL ALASKA NEAR AND JUST NORTH OF AN
EXPECTED ENHANCED STORM TRACK OVER THE GULF OF ALASKA.


TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 30% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 40% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
AND 30% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: 0Z ECMWF ENSEMBLE MEAN.

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG TEMPERATURE AND PRECIPITATION TOOLS IN SPITE OF SOME MODEL
UNCERTAINTY IN THE PREDICTION OF 500-HPA CIRCULATION.

8-14 DAY OUTLOOK FOR APR 07 - 13 2015

THE PREDICTED 500-HPA CIRCULATION FOR WEEK-2 IS SIMILAR TO THE 6-10 DAY MEAN
EXCEPT THAT THE ANOMALY CENTERS ARE ABOUT 10 DEGREES LONGITUDE TO THE EAST OF
THEIR FORECAST MEAN POSITION ON THE 6-10 DAY FORECAST. THE AMPLITUDE OF THE
500-HPA FLOW IS FAIRLY LOW.

MOSTLY ZONAL 500-HPA FLOW AND A WEAK RIDGE OVER THE EASTERN CONUS ELEVATE
CHANCES FOR ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE EASTERN AND CENTRAL
CONUS, ALTHOUGH BELOW-NORMAL TEMPERATURES ARE SLIGHTLY FAVORED OVER PARTS OF
THE NORTHEAST AND THE GREAT LAKES DUE THE POSSIBILITY OF COLD AIR ASSOCIATED A
TROUGH FORECAST OVER EASTERN CANADA. THE AMPLITUDE OF THE WESTERN TROUGH IS
QUITE LOW, GIVING NEAR-NORMAL TEMPERATURES A SLIGHT EDGE OVER BELOW-NORMAL MEAN
TEMPERATURES FOR THE WEEK-TWO MEAN. TEMPERATURES ARE UNCERTAIN FOR ALASKA, WITH
ABOVE-NORMAL TEMPERATURES FAVORED FOR SOME COASTAL AREAS NEAR THE GULF OF
ALASKA WHERE SEA SURFACE TEMPERATURES ARE ABOVE-NORMAL. NEAR NORMAL
TEMPERATURES FAVORED ELSEWHERE IN THE STATE.

THE PRECIPITATION OUTLOOK IS QUITE SIMILAR TO THE 6-10 DAY OUTLOOK, WITH
ABOVE-MEDIAN PRECIPITATION AMOUNTS FAVORED THROUGHOUT MUCH OF THE EASTERN AND
EAST-CENTRAL CONUS, AND BELOW-MEDIAN PRECIPITATION FAVORED FROM THE SOUTHWEST
CONUS THROUGH THE NORTHERN GREAT PLAINS. THE WESTERN TROUGH CONTINUES TO FAVOR
ABOVE-MEDIAN PRECIPITATION AMOUNTS FOR PARTS OF THE PACIFIC NORTHWEST, ALTHOUGH
CONFIDENCE IS LOW GIVEN THE RELATIVELY WEAK EXPECTED AMPLITUDE OF THE 500-HPA
FLOW. A TROUGH PREDICTED OVER WESTERN ALASKA ELEVATE THE CHANCES FOR
ABOVE-MEDIAN PRECIPITATION FOR THE WESTERN PART OF THE STATE, WITH SOME TOOLS
ALSO INDICATED ABOVE-MEDIAN PRECIPITATION FOR PARTS OF THE ALASKA PANHANDLE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 30% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 40% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, AND 30% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO GOOD MODEL AND TOOL AGREEMENT, OFFSET BY LARGE ENSEMBLE SPREAD AND POOR
DETERMINISTIC RUN-TO-RUN CONTINUITY.

FORECASTER: DAVE UNGER

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
APRIL 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:
19850410 - 19620403 - 19600406 - 19940331 - 20080310


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:
19850410 - 19600408 - 19620403 - 20080309 - 19970321


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 05 - 09 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 07 - 13 2015

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