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FXUS06 KWBC 241907
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU APRIL 24 2014

6-10 DAY OUTLOOK FOR APR 30 - MAY 04, 2014

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN VERY GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN OVER NORTH AMERICA. THE NCEP GEFS, ECMWF AND CANADIAN MODEL
ENSEMBLE MEANS FORECAST A TROUGH OVER THE EASTERN U.S. AND A RIDGE OVER THE
WEST. THE GEFS MEAN FORECASTS A MORE AMPLIFIED TROUGH THAN THE CANADIAN AND
ECMWF. A TROUGH IS FORECAST TO THE WEST OF ALASKA. HEIGHTS ARE FORECAST TO BE
ABOVE NORMAL OVER THE WEST AND BELOW NORMAL OVER THE EAST, AND ABOVE NORMAL
OVER MOST OF ALASKA.

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 PREDICTED TO BE 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 EAST OF THE ROCKY MOUNTAINS DUE TO THE IMPACT OF A
PREDICTED TROUGH.

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

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY`S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...20 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 20
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
VERY GOOD AGREEMENT AMONG THE ENSEMBLE MODEL FORECASTS, AND GOOD AGREEMENT
AMONG FORECAST TOOLS.

8-14 DAY OUTLOOK FOR MAY 02 - 08 2014

WHILE MODEL ENSEMBLE MEAN SOLUTIONS CONTINUE TO BE IN GOOD AGREEMENT FOR THE
WEEK-2 FORECAST, THE SPREAD OF THE ENSEMBLE MEMBERS INCREASES SUBSTANTIALLY
BETWEEN THE 6-10 DAY PERIOD AND THE 8-14 DAY PERIOD. IN THE OFFICIAL BLENDED
500-HPA HEIGHT FORECAST, THE PREDICTED RIDGE AND TROUGH OVER THE U.S. IS MUCH
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 REMAIN BELOW
NORMAL.

WHILE IT CONTINUES TO BE MOST LIKELY THAT AVERAGE TEMPERATURES WILL BE ABOVE
NORMAL IN THE WEST, PROBABILITIES ARE SIGNIFICANTLY LOWER FOR THE 8-14 DAY
PERIOD COMPARED TO 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 TEMPERATURES FOR THE PERIOD WILL BE
BELOW NORMAL IS GREATEST FOR THE GULF COAST AND FLORIDA WITH THE PREDICTED
PERSISTENCE OF THE TROUGH OVER THE EAST.

THE LIKELIHOOD THAT PRECIPITATION AMOUNTS WILL BE ABOVE MEDIAN DURING THE 8-14
DAY PERIOD CONTINUES WITH LESS CONFIDENCE RELATIVE TO THE 6-10 DAY PERIOD FOR
THE NORTHEAST. PRECIPITATION TOTALS ARE MOST LIKELY TO BE BELOW MEDIAN IN THE
SOUTHERN PLAINS AND THE SOUTHEAST. PRECIPITATION AMOUNTS ARE MOST LIKELY TO BE
ABOVE MEDIAN IN SOUTHERN ALASKA AND THE PANHANDLE AND THE NORTHERN ROCKIES,
WITH A POTENTIAL TROUGH FORECAST OFF OF THE PACIFIC COAST.


THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10 PERCENT OF TODAY`S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 11...50 PERCENT OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED
ON DAY 11...AND 20 PERCENT OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO LARGE SPREAD IN THE ENSEMBLE MODEL FORECASTS, AND SOME DISAGREEMENT IN THE
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:
19910404 - 19600413 - 20070423 - 19800404 - 19690418


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:
19600412 - 20070422 - 19690416 - 19800406 - 19930425


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 30 - MAY 04, 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    N     OREGON      A    B     NRN CALIF   A    B
SRN CALIF   A    B     IDAHO       A    B     NEVADA      A    B
W MONTANA   A    B     E MONTANA   B    B     WYOMING     B    B
UTAH        A    B     ARIZONA     A    N     COLORADO    B    B
NEW MEXICO  B    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    B
ARKANSAS    B    B     LOUISIANA   B    B     WISCONSIN   B    N
ILLINOIS    B    N     MISSISSIPPI B    B     MICHIGAN    B    A
INDIANA     B    A     OHIO        B    A     KENTUCKY    B    A
TENNESSEE   B    N     ALABAMA     B    N     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  B    A     S CAROLINA  B    A     GEORGIA     B    N
FL PNHDL    B    N     FL PENIN    B    A     AK N SLOPE  A    N
AK ALEUTIAN A    N     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 MAY 02 - 08 2014

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