Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1
000
FXUS06 KWBC 311905
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE MARCH 31 2015

6-10 DAY OUTLOOK FOR APR 06 - 10 2015

TODAY`S MODELS ARE IN GOOD AGREEMENT ON THE EXPECTED MEAN 500-HPA HEIGHTS FOR
THE 6-10 DAY PERIOD. MODELS PREDICT A BROAD TROUGH WITH AN AXIS LOCATED NEAR
THE WEST COAST OF THE CONUS. A WEAK RIDGE IS PREDICTED BY ALL MODELS OVER THE
SOUTHEASTERN CONUS WITH A TROUGH LOCATED OVER EASTERN QUEBEC AND THE CANADIAN
MARITIME PROVINCES. A STRONG PACIFIC JET IS FORECAST OVER AND JUST SOUTH OF THE
ALEUTIANS WITH MOST OF ALASKA FORECAST TO BE UNDER A 500-HPA TROUGH. THE 06Z
GEFS MEAN WAS SLIGHTLY FAVORED IN TODAY`S BLEND BECAUSE ITS SOLUTION BETTER
AGREES WITH THE CANADIAN ENSEMBLES OVER THE WEST COAST. THIS SOLUTION FAVORS A
WEAKLY SPLIT FLOW OVER THE WEST COAST, RATHER THAN THE MORE PHASED TROUGH
PREDICTED BY THE ECMWF.

THE FORECAST RIDGE OVER THE EASTERN CONUS ELEVATES THE CHANCES FOR ABOVE-NORMAL
TEMPERATURES FOR MUCH OF THE EASTERN AND CENTRAL CONUS. TEMPERATURES NEAR THE
MID-ATLANTIC STATES ARE UNCERTAIN DUE TO THE POSSIBILITY OF BACK-DOOR COLD
FRONTS PUSHING COOL AIR FROM NEW ENGLAND AND EASTERN CANADA SOUTHWARD. SURFACE
TEMPERATURES FROM THE MODELS SHOW A STRONG TEMPERATURE GRADIENT BETWEEN
BELOW-NORMAL TEMPERATURES FAVORED IN NEW ENGLAND AND ABOVE-NORMAL TEMPERATURES
FAVORED IN THE SOUTHEAST CONUS. NEAR- TO BELOW-NORMAL TEMPERATURES ARE FAVORED
FOR MUCH OF THE WEST NEAR THE EXPECTED WEST COAST TROUGH. TODAY`S MODELS ARE IN
BETTER AGREEMENT THAN YESTERDAY`S FOR NEAR- TO BELOW-NORMAL TEMPERATURES FOR
MUCH OF ALASKA, WITH THE CHANCES FOR ABOVE-NORMAL TEMPERATURES SLIGHTLY
ENHANCED ALONG THE SOUTHERN COAST 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 NEAR THE WEST COAST FROM THE CENTRAL
CALIFORNIA COAST TO THE PACIFIC NORTHWEST NEAR THE EXPECTED WESTERN TROUGH.
BECAUSE THE PACIFIC JET IS PREDICTED TO WEAKEN AS IT APPROACHES THE WEST COAST
OF NORTH AMERICA, THE AREA OF ENHANCED CHANCES OF ABOVE-MEDIAN PRECIPITATION
EXTENDS ONLY SLIGHTLY INLAND, WITH BELOW-MEDIAN PRECIPITATION FAVORED FARTHER
INLAND FROM THE SOUTHWEST TO THE NORTHERN HIGH PLAINS. 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 40% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 30% 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: 6Z GEFS ENSEMBLE MEAN.

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG MODEL ENSEMBLES AND GOOD AGREEMENT AMONG TEMPERATURE AND
PRECIPITATION TOOLS.

8-14 DAY OUTLOOK FOR APR 08 - 14 2015

THE PREDICTED 500-HPA CIRCULATION FOR WEEK-2 IS VERY SIMILAR TO THE 6-10 DAY
FORECAST, WITH NO SUBSTANTIAL CHANGES IN ANY OF THE UPPER LEVEL FEATURES.
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 NEW ENGLAND DUE THE POSSIBILITY OF COLD AIR ASSOCIATED A TROUGH FORECAST
OVER EASTERN CANADA. TEMPERATURES IN THE WESTERN CONUS ARE SOMEWHAT UNCERTAIN
DUE TO THE UNCERTAIN AMPLITUDE OF THE TROUGH PREDICTED OVER THE WEST COAST.
TEMPERATURES BASED ON CALIBRATED FORECASTS OF NEAR-SURFACE MODEL TEMPERATURES
SLIGHTLY FAVOR ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE WEST, IN SPITE OF THE
BELOW NORMAL UPPER-LEVEL HEIGHTS FORECAST NEAR THE WESTERN TROUGH. THE LACK OF
SNOW COVER MAY HELP ELEVATE CHANCES FOR ABOVE NORMAL TEMPERATURES IN HIGHER
TERRAIN, AND ABOVE-NORMAL SEA-SURFACE TEMPERATURES MAY ENHANCE CHANCES FOR
ABOVE-NORMAL TEMPERATURES IN ALONG THE COAST IN THE PACIFIC NORTHWEST AND
SOUTHERN CALIFORNIA.  NEAR-NORMAL TEMPERATURES ARE FAVORED ELSEWHERE IN THE
WEST. TEMPERATURES HAVE BEEN REVISED TOWARD COOLER TEMPERATURES RELATIVE TO
YESTERDAY`S 8-14 DAY OUTLOOK IN ALASKA DUE TO INCREASING AGREEMENT AMONG MODELS
ON A FAIRLY DEEP TROUGH OVER THE STATE. THE CHANCES OF BELOW-TEMPERATURES ARE
ELEVATED IN TODAY`S OUTLOOK IN MOST OF ALASKA EXCEPT ALONG THE SOUTH COAST
WHERE NEAR-NORMAL TEMPERATURES ARE FAVORED, AND ALONG THE PANHANDLE WHERE ABOVE
NORMAL SEA SURFACE TEMPERATURES MAY ENHANCE CHANCES OF ABOVE-NORMAL
TEMPERATURES IN COASTAL AREAS.

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 PARTS OF THE
SOUTHWEST CONUS THROUGH THE NORTHERN GREAT PLAINS. ABOVE-MEDIAN PRECIPITATION
AMOUNTS ARE FAVORED ALONG MUCH OF THE WEST COAST ASSOCIATED WITH THE WESTERN
TROUGH. THE GEFS PRECIPITATION FORECAST INDICATES ABOVE-MEDIAN PRECIPITATION
FOR THE SOUTHWESTERN CONUS, CONTRADICTED BY THE ECMWF, SUGGESTING UNCERTAINTY
FOR PRECIPITATION OVER THE DESERT SOUTHWEST. A TROUGH PREDICTED OVER WESTERN
ALASKA ELEVATE THE CHANCES FOR ABOVE-MEDIAN PRECIPITATION FOR WESTERN AND
SOUTHERN PARTS OF THE STATE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 40% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 30% 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 UNCERTAINTY IN MUCH OF THE WEST DUE
TO INCONSISTENT INDICATIONS FOR BOTH TEMPERATURE AND PRECIPITATION AMONG SOME
TOOLS.

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:
19600407 - 19850410 - 19940331 - 19600321 - 19780329


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:
19600408 - 19850410 - 19780327 - 19600322 - 19950401


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 06 - 10 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  N    A     OREGON      B    A     NRN CALIF   B    A
SRN CALIF   N    N     IDAHO       B    N     NEVADA      B    N
W MONTANA   N    B     E MONTANA   A    B     WYOMING     N    B
UTAH        B    B     ARIZONA     N    B     COLORADO    A    B
NEW MEXICO  A    B     N DAKOTA    A    B     S DAKOTA    A    B
NEBRASKA    A    B     KANSAS      A    N     OKLAHOMA    A    A
N TEXAS     A    A     S TEXAS     A    A     W TEXAS     A    N
MINNESOTA   N    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     A    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        B    A     RHODE IS    B    A
PENN        N    A     NEW JERSEY  N    A     W VIRGINIA  A    A
MARYLAND    N    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    A     AK N SLOPE  B    N
AK ALEUTIAN A    A     AK WESTERN  N    A     AK INT BSN  N    N
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    A    A



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 08 - 14 2015

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

$$



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.