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FXUS06 KWBC 202001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI JANUARY 20 2017

6-10 DAY OUTLOOK FOR JAN 26 - 30 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 EASTERN CONUS, WHILE A RIDGE IS ANTICIPATED ALONG
THE WEST COAST OF THE CONUS. TODAY`S BLENDED 500-HPA CHART INDICATES BELOW
NORMAL HEIGHTS OVER WESTERN ALASKA AND THE EASTERN HALF OF THE CONUS, AND ABOVE
NORMAL HEIGHTS ELSEWHERE.

LARGE POSITIVE TEMPERATURE ANOMALIES ARE FORECAST DURING THE EARLY PART OF THE
6-10 DAY PERIOD IN PARTS OF THE GREAT LAKES REGION AND THE NORTHEASTERN U.S.
WHICH, DESPITE NEGATIVE HEIGHT ANOMALIES FORECAST OVER THESE REGIONS, FAVOR
ABOVE NORMAL TEMPERATURES FOR THE 6-10 DAY PERIOD AS A WHOLE. ANOMALOUSLY HIGH
SURFACE PRESSURE FORECAST OVER THE WESTERN CONUS FAVORS NIGHTTIME TEMPERATURE
INVERSIONS AND VERY LARGE NEGATIVE TEMPERATURE ANOMALIES. THIS LEADS TO A
SIGNIFICANTLY INCREASED CHANCE FOR BELOW NORMAL TEMPERATURES FOR THE WESTERN
CONUS. ANOMALOUS SOUTHERLY LOW-LEVEL FLOW ENHANCES THE LIKELIHOOD FOR ABOVE
NORMAL TEMPERATURES FOR MUCH OF ALASKA, EXCEPT FOR PARTS OF WESTERN ALASKA
WHERE NEGATIVE HEIGHT ANOMALIES FAVOR BELOW NORMAL TEMPERATURES.

AN ACTIVE STORM TRACK THAT BRINGS STORM SYSTEMS ONSHORE IN ALASKA FAVORS ABOVE
MEDIAN PRECIPITATION FOR ALASKA. A FEW SHORTWAVES FORECAST TO MOVE ACROSS THE
GREAT LAKES REGION INCREASE CHANCES FOR ABOVE MEDIAN PRECIPITATION IN THAT
REGION. AN ANOMALOUSLY STRONG RIDGE FORECAST ALONG THE WEST COAST OF THE U.S.
IS EXPECTED TO PREVENT STORM SYSTEM ACTIVITY FROM MOVING INTO THE CONUS FROM
THE PACIFIC, INCREASING THE LIKELIHOOD FOR BELOW MEDIAN PRECIPITATION IN THE
WESTERN U.S. ANOMALOUS NORTHERLY LOW-LEVEL FLOW AND SURFACE HIGH PRESSURE FAVOR
BELOW MEDIAN PRECIPITATION FOR THE SOUTHERN PLAINS EASTWARD TO THE EASTERN U.S.

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


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

8-14 DAY OUTLOOK FOR JAN 28 - FEB 03, 2017

BY THE WEEK-2 PERIOD, THE TROUGH NEAR ALASKA IS FORECAST TO WEAKEN, AND
POSITIVE HEIGHT ANOMALIES ARE EXPECTED ACROSS THE ALEUTIANS, GULF OF ALASKA,
AND THE WESTERN HALF OF NORTH AMERICA, WHILE THE DOWNSTREAM TROUGH IS FORECAST
TO PERSIST OVER THE EASTERN HALF OF NORTH AMERICA.

THE TEMPERATURE PROBABILITY FORECAST DURING THE WEEK-2 PERIOD FEATURES LOWER
PROBABILITIES THAN DURING THE 6-10 DAY PERIOD DUE TO AN INHERENT INCREASE IN
UNCERTAINTY, ALONG WITH A FEW DIFFERENCES. ONE DIFFERENCE IS AN AREA OF ABOVE
NORMAL TEMPERATURES FAVORED FOR PARTS OF COASTAL CALIFORNIA. AS SURFACE HIGH
PRESSURE IS EXPECTED TO STRENGTHEN OVER THE WESTERN U.S. BY THE WEEK-2 PERIOD,
ANOMALOUS LOW-LEVEL OFFSHORE FLOW IS FORECAST FOR PARTS OF COASTAL CALIFORNIA
WHICH FAVORS WARMING. ANOTHER DIFFERENCE IS THAT A COLD FRONT IS EXPECTED TO
PASS THROUGH THE EASTERN U.S. BY DAY 8, FAVORING NEAR TO BELOW NORMAL
TEMPERATURES FOR THE EASTERN U.S. SOME TEMPERATURE MODERATION IS ALSO FORECAST
BY TODAY`S 0Z ECMWF ENSEMBLE OVER THE CENTRAL PLAINS, ENHANCING THE LIKELIHOOD
OF ABOVE NORMAL TEMPERATURES THERE.

THE PRECIPITATION PROBABILITY FORECAST DURING THE WEEK-2 PERIOD IS SIMILAR TO
THAT IN THE 6-10 DAY PERIOD, WITH LOWER PROBABILITIES DUE TO MORE UNCERTAINTY.
ONE DIFFERENCE IN THE FORECAST PRECIPITATION PATTERN IS THAT STORM SYSTEM
ACTIVITY OVER THE CONUS IS EXPECTED TO DIMINISH BY THE WEEK-2 PERIOD, FAVORING
NEAR TO BELOW MEDIAN PRECIPITATION FOR THE NORTHERN PLAINS AND GREAT LAKES
REGION.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 60% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, AND 40% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY
11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 5 OUT OF 5, DUE
TO VERY GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND THE FORECAST TOOLS.

FORECASTER: MIKE CHARLES

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
FEBRUARY 16

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 - 19930120 - 19730123 - 19800116 - 19870103


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:
20070101 - 19730122 - 19930120 - 19870104 - 20060129


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

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 28 - FEB 03, 2017

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