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FXUS06 KWBC 251910
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI MAY 25 2018

6-10 DAY OUTLOOK FOR MAY 31 - JUN 04, 2018

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN GOOD OVERALL AGREEMENT ON THE PREDICTED
500-HPA MEAN CIRCULATION PATTERN OVER THE FORECAST DOMAIN DURING THE 6-10 DAY
PERIOD. THESE SOLUTIONS PREDICT A TROUGH OVER THE WESTERN CONUS, A RIDGE FROM
THE SOUTH-CENTRAL STATES TO THE MIDDLE MISSISSIPPI VALLEY, AND ANOTHER TROUGH
NEAR THE EAST COAST. ACROSS THE ALASKA DOMAIN, A TROUGH IS EXPECTED OVER THE
BERING SEA, AND A RIDGE IS FORECAST OVER EASTERN MAINLAND ALASKA. THE RIDGE
ANTICIPATED FROM THE SOUTH-CENTRAL STATES TO THE MIDDLE MISSISSIPPI VALLEY IS
FORECAST TO BE HIGHLY ANOMALOUS, WITH 0Z AND 6Z DETERMINISTIC GFS RUNS
PREDICTING 500-HPA HEIGHTS OF 594-DM OR SLIGHTLY GREATER BY EARLY JUNE, WHICH
IS UNUSUAL FOR THIS EARLY IN THE WARM SEASON. ACROSS MUCH OF THE SOUTHERN GREAT
PLAINS, MAXIMUM TEMPERATURES ARE LIKELY TO AVERAGE 15 TO 20 DEGREES F ABOVE
NORMAL THROUGH AT LEAST DAY 7. ANOMALOUS CLOUD COVER AND RAINFALL (ASSOCIATED
WITH ALBERTO) ARE EXPECTED TO REDUCE PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES ACROSS THE SOUTHEAST.

TELECONNECTIONS UPON A PAIR OF 500-HPA HEIGHT ANOMALY CENTERS (NEAR JAMES BAY
AND OVER THE NORTHEAST PACIFIC) SUPPORT AN UPPER-LEVEL TROUGH MOVING INLAND
FROM THE WEST COAST DURING THIS PERIOD. THEREFORE, NEAR TO BELOW NORMAL
TEMPERATURES ARE FAVORED OVER THE INTERIOR NORTHWEST. THE EXPECTATION OF A
PERSISTENT MARINE LAYER TILTS THE ODDS TO BELOW-NORMAL TEMPERATURES ALONG MUCH
OF COASTAL CALIFORNIA.

THE 6-10 DAY TEMPERATURE OUTLOOK IS BASED UPON GEFS AND ECMWF MODEL REFORECAST
GUIDANCE, WPC`S DAYS 6-7 PREDICTED MAXIMUM TEMPERATURE ANOMALIES, ANALOGS, THE
AUTOMATED TEMPERATURE FORECAST, AND THE DAYS 6-10 TEMPERATURE CONSOLIDATION. IN
ADDITION TO THE NEAR TO BELOW NORMAL TEMPERATURES PREDICTED OVER WESTERN
PORTIONS OF THE CONUS, NEAR TO BELOW NORMAL TEMPERATURES ARE ALSO FAVORED OVER
SOUTHERN ALASKA IN ASSOCIATION WITH ONSHORE FLOW. ABOVE NORMAL TEMPERATURES ARE
FAVORED OVER CENTRAL AND NORTHERN ALASKA, RELATED TO A 500-HPA RIDGE AND
POSITIVE HEIGHT ANOMALIES. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED OVER MOST
OF THE CONUS, DUE TO THE EXPECTATION OF RIDGING AND POSITIVE HEIGHT ANOMALIES.

THE 6-10 DAY PRECIPITATION OUTLOOK IS BASED UPON GEFS AND ECMWF MODEL
REFORECAST GUIDANCE, WPC`S PREDICTED STORM TRACKS THROUGH DAY 7 (INCLUDING THE
ANTICIPATED TRACK OF ALBERTO), THE AUTOMATED PRECIPITATION FORECAST, ANALOGS,
AND THE DAYS 6-10 PRECIPITATION CONSOLIDATION. ELEVATED ODDS FOR ABOVE NORMAL
PRECIPITATION ARE INDICATED FROM THE CENTRAL INTERMOUNTAIN REGION TO THE UPPER
MISSISSIPPI VALLEY IN ADVANCE OF A PREDICTED 500-HPA TROUGH. ABOVE NORMAL
PRECIPITATION IS ALSO FAVORED FOR MOST AREAS EAST OF THE MISSISSIPPI RIVER, DUE
IN LARGE PART TO THE EXPECTED TRACK OF ALBERTO, AND OVER SOUTHWEST ALASKA DUE
TO ONSHORE FLOW.  BELOW NORMAL PRECIPITATION IS FAVORED OVER THE SOUTH-CENTRAL
CONUS (UNDER A STRONG RIDGE ALOFT AND DRY SOILS), THE NORTHWEST (BEHIND AN
EXPECTED COLD FRONT), AND EASTERN ALASKA (UNDER A 500-HPA RIDGE).

THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 25% OF TODAY`S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 25% OF TODAY`S 6Z GFS ENSEMBLE MEAN 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 OVERALL MODEL AGREEMENT, AND GOOD FAIRLY GOOD AGREEMENT AMONG THE SURFACE
TEMPERATURE AND PRECIPITATION TOOLS.

8-14 DAY OUTLOOK FOR JUN 02 - 08 2018

THE MODEL CONSENSUS INDICATES A LONGWAVE 500-HPA HEIGHT PATTERN MORE TYPICAL OF
MID-SUMMER THAN THE FIRST WEEK OF JUNE, ESPECIALLY ACROSS THE SOUTH-CENTRAL
CONUS. EARLY IN WEEK-2, THE ENSEMBLE MEANS AND THEIR DETERMINISTIC MODEL RUNS
INDICATE A SIGNIFICANTLY ANOMALOUS RIDGE EXTENDING FROM THE MEXICAN PLATEAU
NORTHEAST TO THE SOUTHERN GREAT PLAINS. THE DETERMINISTIC 6Z GFS MODEL
INDICATES 500-HPA HEIGHTS PEAKING AT 597-DM, OR SLIGHTLY HIGHER, OVER THE TEXAS
BIG BEND REGION DURING THE FIRST DAYS OF JUNE. THEREFORE, HIGH PROBABILITIES
FOR ABOVE NORMAL TEMPERATURES ARE FORECAST ACROSS THE SOUTH-CENTRAL U.S. DURING
WEEK-2. THE LONGWAVE TROUGH, INITIALLY NEAR THE WEST COAST, IS EXPECTED TO BE A
SOURCE FOR SHORTWAVE TROUGHS THAT COULD FLATTEN THE RIDGE ALOFT ACROSS THE
HIGHER LATITUDES OF THE CONUS. RECENT HEAVY RAINFALL AND AN INCREASINGLY WET
TOPSOIL DECREASE PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ACROSS THE EASTERN
U.S., WHILE DRIER TOPSOILS CONTINUE TO CONTRIBUTE TO HIGHER PROBABILITIES FOR
ABOVE-NORMAL TEMPERATURES ACROSS THE CENTRAL AND SOUTHERN GREAT PLAINS.

THE WEEK-2 TEMPERATURE AND PRECIPITATION OUTLOOKS ARE BASED ON THE SAME MODELS
AND TOOLS NOTED FOR THE 6-10 DAY PERIOD. AN INCREASE IN COVERAGE OF ELEVATED
ABOVE NORMAL TEMPERATURE IS INDICATED ACROSS THE WESTERN CONUS, ALONG WITH
RELATIVELY DRY CONDITIONS. DRIER CONDITIONS ARE ALSO FAVORED TO EXPAND
NORTHEASTWARD FROM THE SOUTHERN PLAINS TO THE SOUTHERN GREAT LAKES REGION. A
RELATIVE WEAKNESS IN THE PATTERN FAVORS REDUCED PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES FROM THE NORTHERN PLAINS TO NEW ENGLAND, AND SOUTHWARD ACROSS THE
ATLANTIC COAST STATES TO FLORIDA, RELATIVE TO THE 6-10 DAY PERIOD. HOWEVER,
PROBABILITIES OF NEAR TO ABOVE NORMAL PRECIPITATION ARE EXPECTED FOR THESE SAME
GENERAL REGIONS RELATIVE TO CLIMATOLOGY.

THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 25% OF TODAY`S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 25% 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: BELOW AVERAGE, 2 OUT OF 5, DUE TO
MORE UNCERTAINTY IN THE TEMPERATURE OUTLOOK ACROSS THE NORTH-CENTRAL U.S. AND
LOW PREDICTABILITY IN THE PRECIPITATION OUTLOOK INHERENT DURING THE CONVECTIVE
SEASON.

FORECASTER: ANTHONY A

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 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:
19910513 - 19610605 - 19630512 - 19820519 - 19950602


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:
19910513 - 19610604 - 19950601 - 19910508 - 19820518


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 31 - JUN 04, 2018

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUN 02 - 08 2018

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