Prognostic Meteorological Discussion
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FXUS06 KWBC 182002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST WED JANUARY 18 2017

6-10 DAY OUTLOOK FOR JAN 24 - 28 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS ARE IN VERY GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN PREDICTED OVER NORTH AMERICA. TROUGHS ARE PREDICTED NEAR
THE ALASKA PENINSULA, AND THE EAST-CENTRAL CONUS EXTENDING SOUTHWESTWARD TO THE
SOUTHWEST PORTION OF THE NATION, WHILE RIDGES ARE ANTICIPATED ALONG THE WEST
COAST OF THE CONUS AND OVER THE NORTHEAST CONUS/EASTERN CANADA. A ZONAL FLOW
PATTERN IS EXPECTED ACROSS THE SOUTHERN CONUS. TODAY`S BLENDED 500-HPA CHART
INDICATES NEAR TO ABOVE NORMAL HEIGHTS OVER THE NORTHEAST AND NORTHWEST CONUS,
AND THE ALASKA PANHANDLE, WHILE NEAR TO BELOW NORMAL HEIGHTS ARE ANTICIPATED
OVER THE REMAINDER OF THE CONUS AND ALASKA.

THE ENSEMBLE SPAGHETTI CHARTS INDICATE LOW TO MODERATE SPREAD FOR MOST OF THE
FORECAST DOMAIN. THE AO INDEX WHICH RECENTLY HAS BEEN CLOSE TO ZERO IS FORECAST
TO BE WEAKLY POSITIVE BY DAY 7, AND REMAIN POSITIVE THROUGH DAY 14, ALTHOUGH
THERE IS RELATIVELY LARGE SPREAD AMONG ENSEMBLE MEMBERS REGARDING THE SIGN AND
MAGNITUDE OF THE INDEX. THE PNA INDEX WHICH RECENTLY HAS BEEN STRONGLY POSITIVE
IS FORECAST TO BE NEAR ZERO BY DAY 7, AND REMAIN NEAR ZERO THROUGH DAY 14.

ABOVE NORMAL HEIGHTS AND/OR ANOMALOUS SOUTH/SOUTHEASTERLY FLOW LEAD TO ENHANCED
PROBABILITIES FOR NEAR TO ABOVE NORMAL TEMPERATURES FOR MOST OF THE EASTERN TWO
THIRDS OF THE CONUS. BELOW NORMAL HEIGHTS FAVOR NEAR TO BELOW NORMAL
TEMPERATURES FOR NORTHWESTERN ALASKA, THE ALEUTIANS, AND THE WESTERN THIRD OF
THE CONUS, WHILE ANOMALOUS SOUTHERLY FLOW TILTS THE ODDS TO ABOVE NORMAL
TEMPERATURES FOR SOUTHEASTERN ALASKA AND THE ALASKA PANHANDLE.

A SOUTHERN JET STREAM AND THE TROUGH PREDICTED OVER THE CENTRAL AND
SOUTHWESTERN CONUS ENHANCE PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR THE
SOUTHWESTERN U.S. NORTHEASTWARD ACROSS THE CENTRAL AND SOUTHERN ROCKIES, THE
NORTHERN AND CENTRAL PLAINS, THE UPPER AND MIDDLE MISSISSIPPI VALLEY, GREAT
LAKES, NORTHEAST, AND NORTHERN MID-ATLANTIC. ANOMALOUS WESTERLY FLOW TILTS THE
ODDS TO BELOW MEDIAN PRECIPITATION FOR PARTS OF THE SOUTHERN PLAINS, LOWER
MISSISSIPPI AND TENNESSEE VALLEYS, AND SOUTHEAST. THE RIDGE FORECAST TO BUILD
ALONG THE WEST COAST FAVORS BELOW MEDIAN PRECIPITATION FOR PARTS OF CENTRAL AND
NORTHERN CALIFORNIA, THE PACIFIC NORTHWEST, AND THE GREAT BASIN, REPRESENTING A
MAJOR CHANGE FROM PREVIOUS WEEKS. THE TROUGH EXPECTED OVER THE ALASKA PENINSULA
ENHANCES PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 5% OF
TODAY`S OPERATIONAL 0Z GFS CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, 25% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 7, 5% OF TODAY`S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 10% OF
TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 5% OF YESTERDAY`S 12Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 7


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND THE VARIOUS FORECAST TOOLS, OFFSET
BY UNCERTAINTIES ASSOCIATED WITH A PROGRESSIVE LONG WAVE PATTERN

8-14 DAY OUTLOOK FOR JAN 26 - FEB 01, 2017

TODAY`S ENSEMBLE MEAN DYNAMICAL MODEL FORECASTS ARE IN FAIRLY GOOD AGREEMENT ON
THE PREDICTED 500-HPA CIRCULATION PATTERN OVER NORTH AMERICA FOR THE WEEK-2
PERIOD. THE CIRCULATION PATTERN IS FORECAST TO BE PROGRESSIVE AND AMPLIFIED AS
HEIGHTS FALL OVER THE EAST AND RISE OVER THE WEST. TROUGHS ARE PREDICTED OVER
THE ALEUTIANS, AND THE CENTRAL AND EASTERN CONUS, WHILE A RIDGE IS FORECAST
OVER ALASKA EXTENDING SOUTHEASTWARD TO ALONG THE WEST COAST OF THE CONUS. THE
ENSEMBLE SPAGHETTI DIAGRAMS INDICATE LOW TO MODERATE SPREAD ACROSS MOST OF THE
FORECAST DOMAIN, WITH LARGE SPREAD INDICATED OVER THE EAST PACIFIC AND NEAR THE
U.S. WEST COAST. TODAY`S 500-HPA HEIGHT BLEND GENERALLY INDICATES ABOVE NORMAL
HEIGHTS OVER THE WESTERN CONUS AND ALASKA, AND BELOW NORMAL HEIGHTS OVER THE
REMAINDER OF THE CONUS.

HEIGHTS ARE FORECAST TO FALL OVER THE NORTHEAST CONUS DURING THE PERIOD BUT
ENOUGH RESIDUAL WARMTH, EARLY IN WEEK-2, IS ANTICIPATED TO FAVOR ABOVE NORMAL
TEMPERATURES FOR PARTS OF THE NORTHEAST AND GREAT LAKES. BELOW NORMAL HEIGHTS
AND/OR ANOMALOUS NORTHEASTERLY FLOW ENHANCE PROBABILITIES FOR NEAR TO BELOW
NORMAL TEMPERATURES FOR THE WESTERN, SOUTHERN, AND CENTRAL CONUS. ABOVE NORMAL
HEIGHTS AND ANOMALOUS SOUTHERLY FLOW ENHANCE PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES FOR MUCH OF SOUTHERN AND CENTRAL ALASKA AND THE ALASKA PANHANDLE.
ABOVE NORMAL SST`S ENHANCE PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR THE
ALEUTIANS.

THE RIDGE FORECAST TO BUILD ALONG THE WEST COAST TILTS THE ODDS TO BELOW MEDIAN
PRECIPITATION FOR THE WESTERN THIRD OF THE CONUS. ANOMALOUS WESTERLY FLOW
ENHANCES PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR THE SOUTHERN PORTION
OF THE CONUS FROM THE SOUTHERN PLAINS TO THE MID-ATLANTIC COAST. THE TROUGH
OVER THE GREAT LAKES FAVORS ABOVE MEDIAN PRECIPITATION FROM THE NORTHERN PLAINS
EASTWARD TO THE GREAT LAKES AND NORTHEAST CONUS. ANOMALOUS SOUTHERLY FLOW TILTS
THE ODDS TO ABOVE MEDIAN PRECIPITATION FOR MOST OF MAINLAND ALASKA AND THE
ALASKA PANHANDLE. ABOVE NORMAL HEIGHTS FAVORS BELOW MEDIAN PRECIPITATION FOR
THE WESTERN ALEUTIANS.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 5% OF TODAY`S
OPERATIONAL 0Z GFS CENTERED ON DAY 11, 5% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, 30% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 10, AND 10% 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 FAIRLY GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND THE VARIOUS SURFACE
TOOLS, OFFSET BY UNCERTAINTY SURROUNDING THE EXPECTED TRANSITION OF THE LONG
WAVE PATTERN DURING THE PERIOD

FORECASTER: RANDY SCHECHTER

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
JANUARY 19

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:
20070101 - 19890125 - 19640129 - 19741230 - 19730123


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:
20061231 - 19890123 - 19640131 - 19730122 - 19910113


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 24 - 28 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 26 - FEB 01, 2017

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