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FXUS06 KWBC 201901
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU JULY 20 2017

6-10 DAY OUTLOOK FOR JUL 26 - 30 2017

TODAY`S MODELS ARE IN FAIRLY GOOD AGREEMENT ON THE PREDICTED 500-HPA HEIGHT
PATTERN ACROSS THE U.S. TROUGHS ARE PREDICTED OVER THE GULF OF ALASKA AND THE
EASTERN U.S., WHILE RIDGES ARE FORECAST OVER THE ALEUTIANS AND THE WESTERN U.S.
THE CANADIAN ENSEMBLE MEAN SOLUTIONS ARE A BIT MORE AMPLIFIED WITH THE TROUGH
FORECAST OVER THE EASTERN CONUS. THE ENSEMBLE SPAGHETTI CHARTS INDICATE
MODERATE SPREAD OVER MOST OF THE CONUS, AND MODERATE TO LARGE SPREAD OVER THE
EASTERN PACIFIC. MOST OF THE SPREAD OVER THE CONUS SEEMS TO BE RELATED TO
AMPLITUDE DIFFERENCES, WHILE THE OVERALL POSITION OF THE TROUGH AND RIDGE AXES
SHOW RELATIVELY GOOD AGREEMENT. TODAY`S 500-HPA BLEND CHART DEPICTS NEAR TO
BELOW NORMAL HEIGHTS OVER MOST OF THE EASTERN U.S., THE EXTREME NORTHWESTERN
CONUS, NORTHERN ALASKA, AND PARTS OF THE ALASKA PANHANDLE, WHILE NEAR TO ABOVE
NORMAL HEIGHTS ARE ANTICIPATED OVER THE REMAINDER OF THE CONUS AND ALASKA.
EXPECTED HEIGHT ANOMALIES OVER THE CONUS DO NOT EXCEED 30 METERS, WHILE
POSITIVE HEIGHT ANOMALIES FORECAST NEAR THE ALEUTIANS APPROACH 200 METERS.

NEAR TO ABOVE NORMAL HEIGHTS ENHANCE PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE CONUS. THE EXCEPTIONS ARE OVER PARTS OF THE
SOUTHWEST WHERE CLOUDS AND PRECIPITATION ASSOCIATED WITH MONSOONAL FLOW TILT
THE ODDS TO NEAR NORMAL TEMPERATURES, AND OVER PARTS OF THE EASTERN CONUS WHERE
NEAR TO BELOW NORMAL HEIGHTS FAVOR NEAR TO BELOW NORMAL TEMPERATURES. ABOVE
NORMAL HEIGHTS ENHANCE PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR MUCH OF
ALASKA.

THE TROUGH PREDICTED OVER THE EASTERN CONUS FAVORS NEAR TO ABOVE MEDIAN
PRECIPITATION FOR MUCH OF THE REGION. MONSOONAL FLOW ENHANCES PROBABILITIES FOR
ABOVE MEDIAN PRECIPITATIONS FOR PARTS OF THE SOUTHWEST U.S., CENTRAL GREAT
BASIN, AND CENTRAL ROCKIES. RIDGING OVER THE WEST-CENTRAL U.S. TILTS THE ODDS
TO BELOW MEDIAN PRECIPITATION FOR PARTS OF THE CENTRAL AND SOUTHERN GREAT
PLAINS. WITH THE MAIN STORM TRACK EXPECTED OVER SOUTHERN CANADA, BELOW MEDIAN
PRECIPITATION IS ANTICIPATED FOR PARTS OF THE NORTHWEST CONUS. THE AMPLIFIED
RIDGE FORECAST OVER THE ALEUTIANS ENHANCES PROBABILITIES FOR BELOW MEDIAN
PRECIPITATION FOR THE REGION, WHILE A DEEP TROUGH NORTH OF ALASKA FAVORS ABOVE
MEDIAN PRECIPITATION FOR MUCH OF CENTRAL AND NORTHERN ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 15% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 15% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 25%
OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 15% OF YESTERDAY`S 12Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 20% OF TODAY`S 0Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 8, AND 10% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 7


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: BELOW AVERAGE, 2 OUT OF 5, DUE TO
FAIRLY GOOD MODEL AGREEMENT, BUT WEAK LARGE-SCALE ANOMALIES AND SOME
DIFFERENCES AMONG THE TEMPERATURE AND PRECIPITATION TOOLS.

8-14 DAY OUTLOOK FOR JUL 28 - AUG 03, 2017

THE PATTERN FORECAST DURING THE WEEK-2 PERIOD IS VERY SIMILAR TO THE 6-10 DAY
PERIOD, EXCEPT SHIFTED WESTWARD A BIT. ENSEMBLE SPREAD CONTINUES TO BE MODERATE
ACROSS MOST OF THE CONUS, AND MODERATE TO LARGE OVER THE EASTERN PACIFIC AND
GULF OF ALASKA. THE BLENDED 500-HPA HEIGHT CHART INDICATES NEAR TO BELOW NORMAL
HEIGHTS OVER THE EASTERN U.S., NORTHEASTERN ALASKA, AND THE ALASKA PANHANDLE,
AND NEAR TO ABOVE NORMAL HEIGHTS OVER THE CENTRAL AND WESTERN CONUS,
SOUTHWESTERN ALASKA, AND THE ALEUTIANS. PARTS OF THE WESTERN CONUS ARE
ANTICIPATED TO HAVE POSITIVE HEIGHT ANOMALIES IN EXCESS OF 30 METERS.

THE EXPECTED TEMPERATURE ANOMALY PATTERN FOR WEEK-2 IS QUITE SIMILAR TO THAT
FORECAST FOR THE 6-10 DAY PERIOD, ALTHOUGH AS THE TROUGH OVER THE EAST
RETROGRADES SLIGHTLY, A WARMER PATTERN IS ANTICIPATED OVER PARTS OF THE
NORTHEAST. SLIGHTLY LOWER HEIGHTS FORECAST OVER NORTHEASTERN ALASKA INTRODUCES
ENHANCED PROBABILITIES FOR BELOW NORMAL TEMPERATURES FOR PARTS OF EAST-CENTRAL
ALASKA.

THE TROUGH FORECAST FOR THE EASTERN CONUS ENHANCES PROBABILITIES FOR ABOVE
MEDIAN PRECIPITATION FOR THE REGION. AS THE RIDGE OVER THE WEST SHIFTS A BIT
WESTWARD DURING WEEK-2, MONSOONAL FLOW IS EXPECTED TO BE ORIENTED ALONG A
NORTHWEST TO SOUTHEAST AXIS, TILTING THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR
PARTS OF SOUTHWESTERN TEXAS, SOUTHERN NEW MEXICO, AND MUCH OF ARIZONA. THE
POSITION OF THE WESTERN RIDGE ENHANCES PROBABILITIES FOR BELOW MEDIAN
PRECIPITATION FOR THE NORTHERN U.S. FROM THE PACIFIC NORTHWEST EASTWARD TO THE
WESTERN GREAT LAKES. A TROUGH NORTH OF ALASKA FAVORS ABOVE MEDIAN PRECIPITATION
FOR THE NORTHERN PART OF THE STATE, WHILE THE AMPLIFIED RIDGE NEAR THE
ALEUTIANS ENHANCES PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR THAT REGION
AND SOUTHWESTERN MAINLAND ALASKA.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 10% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 20% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 10, 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 15% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED
ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO FAIRLY GOOD MODEL AGREEMENT, BUT WEAK LARGE-SCALE ANOMALIES AND SOME
DIFFERENCES AMONG THE TEMPERATURE AND PRECIPITATION TOOLS.

FORECASTER: RANDY S

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
AUGUST 17

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:
19790803 - 20050630 - 19780724 - 19790728 - 20040719


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:
19790802 - 20050630 - 19780723 - 19790728 - 20050720


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 26 - 30 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 28 - AUG 03, 2017

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