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FXUS06 KWBC 241930
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED MAY 24 2017

6-10 DAY OUTLOOK FOR MAY 30 - JUN 03, 2017

RECENT ENSEMBLE MEAN SOLUTIONS OF THE NCEP GEFS, ECMWF, AND CANADIAN MODELS ARE
IN GOOD AGREEMENT ON THE LARGE SCALE CIRCULATION PATTERN FORECAST FOR THE 6-10
DAY PERIOD. MODELS FORECAST TROUGHING OVER THE ALEUTIAN ISLANDS, WITH A RIDGE
EXTENDING FROM EASTERN ALASKA SOUTHWARD OVER WESTERN CANADA INTO THE WESTERN
CONUS, A SHORTWAVE TROUGH NEAR THE COAST OF CALIFORNIA, AND A TROUGH OVER
EASTERN NORTH AMERICA. HIGH RESOLUTION MODEL RUNS OF THE NCEP GFS AND ECMWF
PREDICT SIMILAR FLOW PATTERNS. TODAY`S MANUAL BLEND OF THE 500-HPA HEIGHT FIELD
INDICATES ABOVE NORMAL HEIGHTS OVER MOST OF ALASKA, THE WESTERN CONUS, AND
ALONG THE GULF COAST, WITH BELOW NORMAL HEIGHTS ANTICIPATED ELSEWHERE.

ABOVE NORMAL TEMPERATURES ARE FORECAST FOR MUCH OF THE WESTERN U.S., WHERE
ATMOSPHERIC HEIGHTS ARE ABOVE NORMAL. PROBABILITIES ARE GREATEST FOR THE
PACIFIC NORTHWEST WHERE TOOLS ARE IN THE BEST AGREEMENT. WITH A PREDICTED
TROUGH TO THE EAST, AND ANOMALOUS NORTHERLY MID-LEVEL ATMOSPHERIC FLOW OVER THE
CENTRAL U.S., BELOW NORMAL TEMPERATURES ARE MOST LIKELY FROM JUST EAST OF THE
ROCKY MOUNTAINS TO THE GREAT LAKES REGION, AS WELL AS THE MISSISSIPPI AND OHIO
VALLEYS. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR PARTS OF THE GULF AND
ATLANTIC COASTS, WHERE HEIGHTS ARE PREDICTED TO BE NEAR TO ABOVE NORMAL. ABOVE
NORMAL TEMPERATURES ARE ALSO PREDICTED FOR MOST OF ALASKA.

TROUGHING TO THE WEST OF ALASKA LEADS TO A FORECAST OF ABOVE MEDIAN
PRECIPITATION FOR WESTERN REGIONS OF THE STATE AND ALONG THE NORTH SLOPE. BELOW
MEDIAN PRECIPITATION IS LIKELY FOR SOUTHEASTERN REGIONS OF THE STATE, INCLUDING
THE ALASKA PANHANDLE, UNDER THE PREDICTED MID-LEVEL RIDGE. ENHANCED
PROBABILITIES OF BELOW MEDIAN PRECIPITATION EXTEND SOUTHWARD INTO THE PACIFIC
NORTHWEST AND EASTWARD TO THE NORTHERN PLAINS. ABOVE MEDIAN PRECIPITATION IS
FAVORED FOR A LARGE AREA OF THE CONUS FROM THE SOUTHERN AND CENTRAL ROCKIES
ACROSS THE SOUTHERN PLAINS, INTO MOST OF THE CONUS TO THE EAST OF THE
MISSISSIPPI VALLEY.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 25% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 25% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, AND 50%
OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8


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

8-14 DAY OUTLOOK FOR JUN 01 - 07 2017

ENSEMBLE MEAN FORECASTS FROM THE NCEP GEFS, ECMWF, AND CANADIAN MODELS SOMEWHAT
PERSIST THE CIRCULATION PATTERN FROM THE 6-10 DAY PERIOD INTO THE 8-14 DAY
PERIOD. SOME DE-AMPLIFICATION OF ANOMALIES OVER NORTH AMERICA RESULT FROM AN
INCREASE IN THE ENSEMBLE SPREAD AT LEAD TIMES OF THE 8-14 DAY PERIOD FORECAST.
A SHORTWAVE TROUGH IS PREDICTED NEAR THE PACIFIC COAST OF CALIFORNIA IN THE
8-14 DAY PERIOD, WHILE THE TROUGH PREDICTED OVER THE EASTERN CONUS IS MUCH LESS
AMPLIFIED. THE TEMPERATURE AND PRECIPITATION PATTERNS FORECAST FOR THE 8-14 DAY
PERIOD ARE SOMEWHAT SIMILAR TO THE 6-10 DAY PERIOD FORECAST, WITH SOME SLIGHT
CHANGES NOTED BELOW.

BELOW NORMAL TEMPERATURES ARE PREDICTED FOR PARTS OF THE SOUTH COAST OF ALASKA
BY THE ECMWF AND GEFS ENSEMBLE PREDICTION SYSTEMS. PROBABILITIES OF BELOW
NORMAL TEMPERATURES IN THE EASTERN HALF OF THE CONUS ARE LOWER AND LESS
EXTENSIVE DURING THE WEEK-2 PERIOD DUE TO MORE UNCERTAINTY IN THE DEPTH OF THE
TROUGH THERE.

ABOVE MEDIAN PRECIPITATION IS NOW LIKELY FOR MOST OF ALASKA DUE TO A PREDICTED
INCREASE IN STORM SYSTEM ACTIVITY THERE DURING THE WEEK-2 PERIOD. STORM
ACTIVITY IS FORECAST TO DIMINISH SOMEWHAT BY WEEK-2 IN THE NORTHEAST, FAVORING
NEAR MEDIAN PRECIPITATION THERE, WHILE THE SOUTHERN CONUS IS EXPECTED TO SEE A
CONTINUED ACTIVE PERIOD OF STORMS DURING WEEK-2, FAVORING ABOVE MEDIAN
PRECIPITATION FROM PARTS OF THE FOUR CORNERS REGION EASTWARD TO THE MID
ATLANTIC REGION.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 50% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, AND 50% 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 SOME DISAGREEMENT BETWEEN MODEL FORECASTS AND AMONG TEMPERATURE AND
PRECIPITATION TOOLS, AND INCREASING UNCERTAINTY AS INDICATED BY THE ENSEMBLE
SPREAD.

FORECASTER: MIKE C

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
JUNE 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:
19520517 - 19660511 - 19850515 - 19660519 - 20010523


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:
19520517 - 19850515 - 19660515 - 20060517 - 20030508


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 30 - JUN 03, 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 01 - 07 2017

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

                           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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