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FXUS06 KWBC 061931
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 06 2015

6-10 DAY OUTLOOK FOR MAY 12 - 16 2015

THE AVAILABLE MODELS EXHIBIT GOOD AGREEMENT ON THE 500-HPA HEIGHT FIELD OVER
NORTH AMERICA. MOST MODELS DEPICT A TROUGH NEAR THE WEST COAST OF THE CONUS
THAT EXTENDS INLAND TO THE GREAT BASIN AND SOUTHWEST, RIDGING OVER THE CENTRAL
PORTIONS OF THE CONUS, AND A DEEP TROUGH OVER NORTHEAST CANADA. THE AREAS OF
MOST UNCERTAINTY ARE OVER THE GREAT LAKES, WHERE SOME MODELS HAVE A TROUGH AND
OTHER MODELS HAVE ABOVE NORMAL HEIGHTS. MODEL SOLUTIONS WITH A SLIGHTLY DEEPER
TROUGH ARE FAVORED, AS THAT MORE CLOSELY REFLECTS THE PATTERN DURING THE PAST
30 DAYS AND IS ALSO CONSISTENT WITH RIDGING OVER NORTHWEST NORTH AMERICA.

THE AVERAGE ANALOG CORRELATION SCORE AMONG THE AVAILABLE MODELS IS LOWER TODAY
THAN YESTERDAY, SHOWING LESS OF AN ALIGNMENT TO THE HISTORICALLY OBSERVED
PATTERNS. ANOMALY CORRELATION SCORES DURING THE PAST 60 DAYS HAVE DROPPED ABOUT
0.02 POINTS FOR EACH MODEL, TYPICAL DURING THE SPRING. TELECONNECTIONS ON ABOVE
NORMAL HEIGHTS OVER THE CENTRAL CANADA REVEAL WEAK SIGNALS OVER THE CONUS.

THE 500-HPA MANUAL BLEND HEIGHT PATTERN FAVORS ABOVE NORMAL TEMPERATURES OVER
ALASKA DUE TO MEAN SOUTHERLY FLOW IN THE LOW-LEVELS AND ABOVE NORMAL HEIGHTS
ALOFT. NEAR TO ABOVE NORMAL HEIGHTS AND ONGOING DROUGHT CONDITIONS FAVOR ABOVE
NORMAL TEMPERATURES ACROSS THE PACIFIC NORTHWEST AND NORTHERN ROCKIES.
TROUGHING OVER THE SOUTHWEST INCREASES THE ODDS FOR BELOW NORMAL TEMPERATURES
FROM CALIFORNIA TO THE CENTRAL AND SOUTHERN GREAT PLAINS. SURFACE RIDGING
BUILDING SOUTHWARD FROM CANADA BEHIND A LATE SEASON COLD FRONT INCREASE THE
ODDS FOR BELOW NORMAL TEMPERATURES OVER THE CENTRAL GREAT PLAINS AND GREAT
LAKES. UNCERTAINTY ABOUT THE FINAL POSITION OF THAT FRONT OVER THE SOUTHEAST
RESULTS IN A STEEP DECLINE IN PROBABILITIES FOR ABOVE NORMAL TEMPERATURES ALONG
THE ENTIRE EAST COAST AND PORTIONS OF THE SOUTHEAST.

TROUGHING NEAR THE SOUTHWEST FAVORS ABOVE MEDIAN PRECIPITATION FROM THE
NORTHERN GREAT BASIN AND PACIFIC NORTHWEST TO THE SOUTHERN GREAT PLAINS. THE
POTENTIAL FOR A STALLED FRONT ALONG THE GULF COAST INCREASES THE ODDS FOR ABOVE
MEDIAN PRECIPITATION. IN THE WAKE OF THE FRONT, UNDER MEAN UPPER-LEVEL AND
SURFACE RIDGING, BELOW MEDIAN PRECIPITATION IS FAVORED FROM THE NORTHERN AND
CENTRAL GREAT PLAINS TO THE TENNESSEE VALLEY AND GREAT LAKES, AS WELL AS
PORTIONS OF THE NORTHEAST.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 20%
OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 30% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 25% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD
AGREEMENT AMONG THE MODEL SOLUTIONS, TEMPERED BY DISAGREEMENT AMONG THE SURFACE
TEMPERATURE AND PRECIPITATION TOOLS, AS WELL AS UNCERTAINTY ABOUT THE PLACEMENT
OF A LATE SEASON COLD FRONT.

8-14 DAY OUTLOOK FOR MAY 14 - 20 2015

MODEL SOLUTIONS FOR THE WEEK-2 PERIOD EXHIBIT VERY GOOD AGREEMENT, ALTHOUGH
SLIGHTLY LESS AGREEMENT THAN YESTERDAY. THE AREAS OF DISAGREEMENT OVER THE
CONUS ARE OVER THE NORTHEAST AND THE SOUTHEAST. BOTH AREAS OF DISAGREEMENT
HINGE ON THE PLACEMENT AND ORIENTATION OF THE RIDGE OVER THE NORTHEAST. ANALOG
CORRELATION SCORES LOWER, ON AVERAGE, TODAY THAN YESTERDAY, SUGGESTING LESS
AGREEMENT WITH THIS HISTORICAL RECORD. THE PATTERN IN THE 8-14 DAY PERIOD
REFLECTS A PROGRESSIVE CHANGE FROM THE 6-10 DAY PERIOD, WITH THE TROUGHING OVER
THE GREAT LAKES NO LONGER APPARENT IN THE UPPER-LEVEL PATTERN, AND THE TROUGH
NEAR THE SOUTHWEST CENTERED FARTHER SOUTH.

THE 500-HPA MANUAL BLEND CHART FEATURES A MEAN TROUGH OVER THE ALEUTIANS,
RIDGING FROM EASTERN ALASKA TO THE NORTHERN GREAT PLAINS AND ACROSS THE THE
TENNESSEE VALLEY, AND A TROUGH OVER THE SOUTHWEST.  THAT PATTERN FAVORS ABOVE
NORMAL TEMPERATURES FOR ALL OF ALASKA, AND MOST OF THE CONUS.  BELOW NORMAL
TEMPERATURES ARE FAVORED FROM CENTRAL CALIFORNIA TO SOUTHWEST COLORADO,
SOUTHWARD TO THE RIO GRANDE VALLEY AND OVER ALL OF THE SOUTHWEST. ELSEWHERE IN
THE CONUS, ABOVE NORMAL TEMPERATURES ARE FAVORED.

THE TROUGH OVER THE SOUTHWEST FAVORS ABOVE MEDIAN PRECIPITATION FOR CALIFORNIA,
THE GREAT BASIN, AND THE ENTIRETY OF THE ROCKY MOUNTAINS. MEAN
EAST-SOUTHEASTERLY FLOW ENHANCES THE ODDS OF ABOVE MEDIAN PRECIPITATION FOR THE
SOUTHERN GREAT PLAINS AND GULF COAST, INCLUDING FLORIDA.  BELOW MEDIAN
PRECIPITATION IS FAVORED FROM MISSOURI TO THE MID-ATLANTIC AND CAROLINAS,
NORTHWARD TO NEW ENGLAND BECAUSE OF THE UPSTREAM RIDGE OVER THE CENTRAL PORTION
OF THE CONUS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 25% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 35% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, AND 20%
OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO VERY GOOD AGREEMENT AMONG THE MODELS BUT TEMPERED BY A SLIGHT INCREASE IN
UNCERTAINTY OF SMALLER UPPER-LEVEL FEATURES AND DISAGREEMENTS AMONG THE SURFACE
SPECIFICATION TOOLS.

FORECASTER: MATT ROSENCRANS

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
21

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:
20050418 - 19740428 - 20000417 - 20040520 - 20040416


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:
20000416 - 20040415 - 20050418 - 19740428 - 19510423


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 12 - 16 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 14 - 20 2015

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

$$



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