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FXUS06 KWBC 231937
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED APRIL 23 2014

6-10 DAY OUTLOOK FOR APR 29 - MAY 03, 2014

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN OVER NORTH AMERICA. THE NCEP GEFS AND ECMWF MODEL ENSEMBLE
MEANS FORECAST A TROUGH OVER THE EASTERN U.S. AND A RIDGE OVER THE WEST. THE
CANADIAN ENSEMBLE MEAN FORECASTS A LESS AMPLIFIED RIDGE AND TROUGH. THE
OFFICIAL 500-HPA HEIGHT-BLEND FORECAST MORE HEAVILY WEIGHTS FORECASTS OF THE
ECMWF AND NCEP MODELS THAN THE CANADIAN MODEL. HEIGHTS ARE FORECAST TO BE ABOVE
NORMAL OVER THE WEST AND BELOW NORMAL OVER THE EAST.

AVERAGE TEMPERATURES FOR THE 6-10 DAY PERIOD ARE MOST LIKELY TO BE ABOVE NORMAL
TO THE WEST OF THE ROCKY MOUNTAINS WHERE HEIGHTS ARE ABOVE NORMAL. TEMPERATURES
ARE ALSO MOST LIKELY TO BE ABOVE NORMAL IN ALASKA DUE TO ANOMALOUS, SOUTHERLY
FLOW AHEAD OF A TROUGH TO THE WEST. TEMPERATURES ARE LIKELY TO BE BELOW NORMAL
IN MOST REGIONS EAST OF THE ROCKY MOUNTAINS DUE TO THE IMPACT OF A PREDICTED
TROUGH. TEMPERATURES ARE MORE LIKELY TO BE ABOVE NORMAL IN SOUTHERN FLORIDA.

TOTAL PRECIPITATION FOR THE PERIOD IS MOST LIKELY TO BE ABOVE MEDIAN IN
SOUTHERN ALASKA AHEAD OF THE TROUGH IN THE REGION. PRECIPITATION IS MOST LIKELY
TO BE ABOVE MEDIAN IN THE PACIFIC NORTHWEST AND THE ALASKA PANHANDLE AHEAD OF A
TROUGH OVER THE NORTH PACIFIC. PRECIPITATION IS ALSO LIKELY TO BE ABOVE MEDIAN
IN MOST OF THE EAST, DUE TO THE PREDICTED TROUGH OVER THE REGION. BELOW MEDIAN
PRECIPITATION AMOUNTS ARE FORECAST FOR CALIFORNIA, THE ROCKY MOUNTAINS, THE
SOUTHWEST, AND THE GREAT PLAINS.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY`S OPERATIONAL 6Z
GFS CENTERED ON DAY 8...25 PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON
DAY 8...10 PERCENT OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8...50
PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 10 PERCENT
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8.

MODEL OF THE DAY: 00Z ECMWF ENSEMBLE MEAN

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

8-14 DAY OUTLOOK FOR MAY 01 - 07 2014

THE ECMWF AND NCEP MODEL ENSEMBLE MEAN SOLUTIONS CONTINUE TO BE IN GOOD
AGREEMENT FOR THE WEEK-2 FORECAST, WHILE THE CANADIAN ENSEMBLE HAS GREATER
SPREAD AND DIFFERS FROM THE CONSENSUS. THE ECMWF AND NCEP GEFS MODELS WERE
EQUALLY WEIGHTED TO MAKE THE OFFICIAL 500-HPA HEIGHT FORECAST, WHILE THE
CANADIAN ENSEMBLE WAS NOT USED. THE PREDICTED RIDGE AND TROUGH OVER THE U.S. IS
SOMEWHAT LESS AMPLIFIED IN WEEK-2 RELATIVE TO THE 6-10 DAY PERIOD, WHILE THE
TROUGH PROGRESSES OVER THE EASTERN U.S., WHERE HEIGHTS ARE FORECAST TO BE BELOW
NORMAL.

THE LIKELIHOOD THAT AVERAGE TEMPERATURES WILL BE ABOVE NORMAL IN THE WEST
CONTINUES INTO THE 8-14 DAY PERIOD FROM THE 6-10 DAY PERIOD FORECAST.
PROBABILITIES THAT EASTERN U.S. TEMPERATURES WILL BE BELOW NORMAL CONTINUE TO
BE ENHANCED FOR THE 8-14 DAY PERIOD. THE PROBABILITY THAT THE AVERAGE
TEMPERATURE FOR THE PERIOD WILL BE BELOW NORMAL HAS INCREASED FOR THE EASTERN
GULF COAST AND FLORIDA WITH PREDICTED EASTWARD PROGRESSION OF THE TROUGH.

THE LIKELIHOOD THAT PRECIPITATION AMOUNTS WILL BE ABOVE MEDIAN INTO THE 8-14
DAY PERIOD HAS DECREASED OVER MUCH OF THE EAST RELATIVE TO THE 6-10 DAY PERIOD,
WITH THE EXCEPTION OF THE MID-ATLANTIC AND NEW ENGLAND. PRECIPITATION TOTALS
ARE MOST LIKELY TO BE BELOW MEDIAN IN THE SOUTHERN AND CENTRAL PLAINS AND THE
MISSISSIPPI VALLEY. PRECIPITATION AMOUNTS ARE STILL LIKELY TO BE ABOVE MEDIAN
IN SOUTHERN ALASKA AND THE PANHANDLE.


THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 50 PERCENT OF TODAY`S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11...AND 50 PERCENT OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO SIGNIFICANT SPREAD IN THE ENSEMBLE MODEL FORECASTS, AND SOME DISAGREEMENT BY
THE CANADIAN MODEL FORECAST.

FORECASTER: DAN COLLINS

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 MAY
15

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:
20070423 - 19910404 - 19780403 - 19600413 - 19690415


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:
20070422 - 19690414 - 20040416 - 19780402 - 20090501


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 29 - MAY 03, 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 01 - 07 2014

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