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FXUS06 KWBC 271902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI MARCH 27 2015

6-10 DAY OUTLOOK FOR APR 02 - 06 2015

TODAY`S OFFICIAL 500-HPA HEIGHT MANUAL BLEND REMAINS VERY SIMILAR TO
YESTERDAY`S, WITH THE ONLY APPRECIABLE DIFFERENCE OVER NORTH AMERICA BEING
GENERALLY LOWER HEIGHTS OVER THE CONUS. THE FORECAST PATTERN CONTINUES TO FAVOR
THE ANOMALOUS ADVECTION OF COLD AIR FROM THE POLE SOUTHWARD TOWARD THE NORTHERN
CONUS.

THE VARIOUS DYNAMICAL SURFACE TEMPERATURE TOOLS HAVE COME INTO BETTER AGREEMENT
TODAY, ELIMINATING THE NEED FOR LARGE DEVIATIONS FROM THE AUTOMATED FORECAST.
SOME TWEAKS TOWARD FAVORING COLDER TEMPERATURES WERE MADE IN THE NORTHERN
ROCKIES, WHILE SOME SHIFT TOWARD FAVORING MILDER TEMPERATURES WAS WARRANTED
OVER THE EASTERN CONUS. OVERALL, THE SURFACE TEMPERATURE FORECAST REMAINS IN
LINE WITH THE EVOLUTION OF THE FORECAST THROUGHOUT THE WEEK.

THE SURFACE PRECIPITATION OUTLOOK IS CONSISTENT WITH THE FORECAST 500-HPA
HEIGHT AND SURFACE TEMPERATURE FIELDS, WHICH SUPPORT AN ENHANCED STORM TRACK
FROM THE NORTHERN PLAINS TO THE TENNESSEE VALLEY AND POINTS NORTHEAST.
PROBABILITIES FOR ABOVE-MEDIAN PRECIPITATION ARE A LITTLE HIGHER TODAY DUE TO
BETTER MODEL AGREEMENT ON THE PLACEMENT OF THE MEAN STORM TRACK.

THE PRECIPITATION TOOLS ARE SOMEWHAT CONTRADICTORY OVER ALASKA. FROM A PHYSICAL
STANDPOINT, WEAK ANOMALOUS NORTHERLY FLOW AT MID-LEVELS WOULD SEEM TO FAVOR
BELOW-MEDIAN PRECIPITATION, BUT THE GENERALLY MILD PATTERN AND WEAK TROUGHING
IN THE GULF OF ALASKA FAVORS NEAR-MEDIAN PRECIPITATION.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 10% OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8, 15% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY
8, 15% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, AND 25% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: NO PREFERENCE

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

8-14 DAY OUTLOOK FOR APR 04 - 10 2015

THE FORECAST CIRCULATION FOR WEEK-2 SHOWS SOME NOTABLE EASTWARD PROGRESSION
ACROSS THE CONUS COMPARED TO THE 6-10 DAY PERIOD. HOWEVER, THE DEEP UPPER-LEVEL
TROUGH IS FORECAST TO REMAIN ANCHORED NEAR HUDSON BAY, WHILE ANOMALIES UPSTREAM
OVER THE NORTH PACIFIC ARE OF RATHER SMALL MAGNITUDE. THE ENSEMBLE MEANS ARE IN
REASONABLY GOOD AGREEMENT, THOUGH THE PAST FEW RUNS OF THE DETERMINISTIC GFS
REVEAL POOR RUN-TO-RUN CONTINUITY. THE LOW-AMPLITUDE FORECAST HEIGHT ANOMALIES
OVER THE NORTH PACIFIC ARE LIKELY DUE TO EITHER A FORECAST PATTERN CHANGE OR
LARGE ENSEMBLE SPREAD, NEITHER OF WHICH BODES WELL FOR WEEK-2 PREDICTABILITY.
THE LATTER IS CONFIRMED BY THE SPAGHETTI DIAGRAMS FROM THE THE MAJOR ENSEMBLE
SYSTEMS.

GIVEN THE PREDICTED 500-HPA HEIGHT BLEND DURING WEEK-2, IT SEEMS PRUDENT TO
MAINTAIN A SIMILAR SPATIAL PATTERN WITH RESPECT TO BOTH THE TEMPERATURE AND
PRECIPITATION OUTLOOKS FOR THE 6-10 DAY PERIOD, WITH REDUCED PROBABILITIES AND
SOME PROGRESSION OF THE PATTERN.

THE SURFACE TEMPERATURE TOOLS ARE IN VERY GOOD AGREEMENT ON THE ABOVE PATTERN,
AND SO LITTLE CHANGE TO THE AUTOMATED FORECASTS WAS REQUIRED.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 11, 10% OF TODAY`S
OPERATIONAL 6Z GFS CENTERED ON DAY 11, 35% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 20% 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: 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
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:
19620402 - 19940330 - 19940310 - 20080309 - 20050307


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:
19940309 - 19620401 - 20080308 - 19980317 - 19940330


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 02 - 06 2015

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    N     OREGON      B    B     NRN CALIF   A    B
SRN CALIF   A    B     IDAHO       B    N     NEVADA      N    B
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    N
UTAH        N    B     ARIZONA     A    B     COLORADO    A    B
NEW MEXICO  A    B     N DAKOTA    N    A     S DAKOTA    N    A
NEBRASKA    N    N     KANSAS      A    N     OKLAHOMA    A    A
N TEXAS     A    A     S TEXAS     A    N     W TEXAS     A    B
MINNESOTA   B    A     IOWA        N    A     MISSOURI    N    A
ARKANSAS    A    A     LOUISIANA   A    N     WISCONSIN   B    A
ILLINOIS    N    A     MISSISSIPPI A    A     MICHIGAN    B    A
INDIANA     B    A     OHIO        B    A     KENTUCKY    N    A
TENNESSEE   N    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        B    A     NEW JERSEY  B    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    N
AK ALEUTIAN A    N     AK WESTERN  A    N     AK INT BSN  A    N
AK S INT    A    N     AK SO COAST A    N     AK PNHDL    A    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 04 - 10 2015

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