Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2
000
FXUS06 KWBC 221934
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE APRIL 22 2014

6-10 DAY OUTLOOK FOR APR 28 - MAY 02, 2014

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIR 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 WESTERN U.S.
EXTENDING TOWARDS HUDSON BAY. THE CANADIAN ENSEMBLE IN CONTRAST FORECASTS A
TROUGH OVER THE CENTRAL U.S. AND A RIDGE OVER CENTRAL CANADA. THE OFFICIAL
500-HPA HEIGHT-BLEND FORECAST MORE HEAVILY WEIGHTS THE CONSENSUS FORECAST OF
THE ECMWF AND NCEP MODELS THAN THE CANADIAN MODEL. HEIGHTS ARE FORECAST TO BE
ABOVE NORMAL OVER THE WEST AND OVER THE FAR NORTHERN GREAT PLAINS AND WESTERN
GREAT LAKES REGIONS. HEIGHTS ARE FORECAST TO BE BELOW NORMAL OVER MOST OF THE
EAST.

AVERAGE TEMPERATURES FOR THE 6-10 DAY PERIOD ARE MOST LIKELY TO BE ABOVE NORMAL
IN MOST AREAS WEST OF THE ROCKY MOUNTAINS WHERE HEIGHTS ARE ABOVE NORMAL.
TEMPERATURES ARE MORE LIKELY TO BE NEAR OR BELOW NORMAL IN THE PACIFIC
NORTHWEST ASSOCIATED WITH A FORECAST OF ABOVE MEDIAN PRECIPITATION.
TEMPERATURES ARE ALSO MOST LIKELY TO BE ABOVE NORMAL IN ALASKA DUE TO ANOMALOUS
SOUTHERLY FLOW. 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 THE
PACIFIC NORTHWEST AND THE SOUTHERN ALASKAN PANHANDLE AHEAD OF A TROUGH OVER THE
NORTH PACIFIC. PRECIPITATION IS ALSO LIKELY TO BE ABOVE MEDIAN IN PARTS OF THE
NORTHERN PLAINS AND IN THE EAST, DUE TO THE PREDICTED TROUGH OVER THE REGION.
BELOW MEDIAN PRECIPITATION AMOUNTS ARE FORECAST FOR SOUTHERN ALASKA, THE
CENTRAL ROCKIES, AND THE SOUTHWEST.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY`S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...30 PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8...10 PERCENT OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY
8...40 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
AGREEMENT BETWEEN THE ECMWF AND NCEP GEFS ENSEMBLE MODEL FORECASTS, SOME
DISAGREEMENT BY THE CANADIAN MODEL FORECAST, WITH GOOD AGREEMENT AMONG FORECAST
TOOLS.

8-14 DAY OUTLOOK FOR APR 30 - MAY 06, 2014

THE ECMWF AND NCEP MODEL ENSEMBLE MEAN SOLUTIONS CONTINUE TO BE IN GOOD
AGREEMENT FOR THE WEEK-2 FORECAST, WHILE THE CANADIAN ENSEMBLE MEAN 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. UPPER-LEVEL HEIGHTS CONTINUE TO BE ABOVE NORMAL IN THE WEST IN THE WEEK-2
FORECAST, WHILE THE TROUGH IS PREDICTED TO PROGRESS 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
CONTINUE 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 CENTRAL U.S. RELATIVE TO THE 6-10 DAY
PERIOD. PRECIPITATION TOTALS ARE MOST LIKELY TO BE BELOW MEDIAN IN THE SOUTHERN
PLAINS AND THE MISSISSIPPI VALLEY. PRECIPITATION AMOUNTS ARE STILL LIKELY TO BE
ABOVE MEDIAN ALONG THE EAST COAST.


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: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO AGREEMENT BETWEEN THE ECMWF AND NCEP GEFS ENSEMBLE MODEL FORECASTS, SOME
DISAGREEMENT BY THE CANADIAN MODEL FORECAST, WITH GOOD AGREEMENT AMONG FORECAST
TOOLS.

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 - 20000505 - 19910405 - 19690415 - 19900420


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:
20000505 - 19690414 - 19910406 - 20070424 - 20030409


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 28 - MAY 02, 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 30 - MAY 06, 2014

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

                           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.