Prognostic Meteorological Discussion
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FXUS06 KWBC 162001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST MON JANUARY 16 2017

6-10 DAY OUTLOOK FOR JAN 22 - 26 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS ARE IN VERY GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN PREDICTED OVER NORTH AMERICA. TROUGHS ARE PREDICTED OVER
WESTERN ALASKA EXTENDING INTO THE GULF OF ALASKA, AND THE CENTRAL CONUS, WHILE
A RIDGE IS ANTICIPATED OVER THE NORTHEAST CONUS. 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 CONUS, THE NORTHERN
MID-ATLANTIC, THE GREAT LAKES, AND THE UPPER MISSISSIPPI VALLEY, WHILE NEAR TO
BELOW NORMAL HEIGHTS ARE ANTICIPATED OVER THE REMAINDER OF THE CONUS AND ALASKA.

THE ENSEMBLE SPAGHETTI CHARTS INDICATE MODERATE TO LARGE SPREAD IN THE NORTHERN
JET STREAM, AND LOW TO MODERATE SPREAD IN THE SOUTHERN JET STREAM. THE AO INDEX
WHICH RECENTLY HAS BEEN WEAKLY POSITIVE/CLOSE TO ZERO IS FORECAST TO REMAIN
WEAKLY POSITIVE/CLOSE TO ZERO 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
BECOME WEAKLY NEGATIVE BY DAY 7, BE CLOSE TO ZERO AT DAY 10, AND REMAIN NEAR
ZERO THROUGH DAY 14.

ABOVE NORMAL HEIGHTS AND/OR THE EXPECTATION OF AIR MASSES OF PACIFIC ORIGIN
LEAD TO ENHANCED PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR MOST OF THE
EASTERN TWO THIRDS OF THE CONUS. BELOW NORMAL HEIGHTS FAVOR NEAR TO BELOW
NORMAL TEMPERATURES FOR ALASKA AND THE WESTERN THIRD OF THE CONUS.

A SOUTHERN JET STREAM AND THE TROUGH PREDICTED OVER THE CENTRAL CONUS ENHANCE
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE CONUS. EXCEPTIONS
ARE OVER MAINE WHERE THE FORECAST RIDGE TILTS THE ODDS TO BELOW MEDIAN
PRECIPITATION, AND OVER PARTS OF THE SOUTHERN PLAINS WHERE ANOMALOUS WESTERLY
FLOW FAVORS BELOW MEDIAN PRECIPITATION. SUBSIDENCE ON THE REAR SIDE OF THE
CENTRAL U.S. TROUGH TILT THE ODDS TO BELOW MEDIAN PRECIPITATION FOR A SMALL
PORTION OF THE NORTHERN ROCKIES. THE TROUGH EXPECTED OVER WESTERN ALASKA
ENHANCE PROBABILITIES FOR ABOVE MEDIAN PRECIPITATIONS FOR THAT REGION WHILE A
WEAK RIDGE TILT THE ODDS TO BELOW MEDIAN PRECIPITATION FOR THE NORTHERN
PORTIONS OF THE STATE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 15%
OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 5% OF TODAY`S OPERATIONAL
0Z GFS CENTERED ON DAY 8, 5% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8,
20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 10% OF YESTERDAY`S
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 5% OF TODAY`S OPERATIONAL 0Z
ECMWF CENTERED ON DAY 8, 15% 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: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
VERY GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND THE VARIOUS FORECAST TOOLS,
PARTIALLY OFFSET BY RELATIVELY LARGE SPREAD AMONG THE ENSEMBLE MEMBERS IN THE
NORTHERN STREAM

8-14 DAY OUTLOOK FOR JAN 24 - 30 2017

TODAY`S ENSEMBLE MEAN DYNAMICAL MODEL FORECASTS ARE IN GOOD AGREEMENT ON THE
PREDICTED 500-HPA CIRCULATION PATTERN OVER NORTH AMERICA FOR THE WEEK-2 PERIOD.
COMPARED TO THE 6-10 DAY PERIOD, A PATTERN CHANGE DURING WEEK-2 IS EXPECTED,
WITH A RIDGE DEVELOPING NEAR THE WEST COAST. TROUGHS ARE PREDICTED OVER THE
ALEUTIANS, AND THE GREAT LAKES EXTENDING SOUTHWESTWARD TO OVER THE SOUTHWEST
CONUS, WHILE A RIDGE IS FORECAST OVER ALASKA EXTENDING SOUTHEASTWARD TO ALONG
THE WEST COAST OF THE CONUS. THE ENSEMBLE SPAGHETTI DIAGRAMS INDICATE MODERATE
SPREAD ACROSS MOST OF THE FORECAST DOMAIN. TODAY`S 500-HPA HEIGHT BLEND
GENERALLY INDICATES BELOW NORMAL HEIGHTS OVER THE SOUTHERN THREE QUARTERS OF
THE CONUS, THE ALEUTIANS, AND WESTERN ALASKA , WHILE ABOVE NORMAL HEIGHTS ARE
ANTICIPATED OVER THE REMAINDER OF THE CONUS, EASTERN ALASKA, AND THE ALASKA
PANHANDLE.

ABOVE NORMAL HEIGHTS AND AIR MASSES OF PACIFIC ORIGIN TILT THE ODDS TO ABOVE
NORMAL TEMPERATURES FOR MUCH OF THE NORTHEASTERN CONUS. BELOW NORMAL SST`S AND
BELOW NORMAL HEIGHTS ENHANCE PROBABILITIES FOR BELOW NORMAL TEMPERATURES FOR
EASTERN FLORIDA AND PARTS OF THE SOUTHEAST COAST. BELOW NORMAL HEIGHTS AND/OR
ANOMALOUS NORTHEASTERLY FLOW FAVOR BELOW NORMAL TEMPERATURES FOR THE WESTERN
THIRD OF THE U.S. AND THE WEST-CENTRAL PORTION OF THE CONUS. ABOVE NORMAL
HEIGHTS AND ANOMALOUS SOUTHERLY FLOW ENHANCE PROBABILITIES FOR ABOVE NORMAL
TEMPERATURES FOR SOUTHEASTERN ALASKA AND THE ALASKA PANHANDLE. BELOW NORMAL
HEIGHTS TILT THE ODDS TO BELOW NORMAL TEMPERATURES FOR PARTS OF NORTHWESTERN
ALASKA.

ANOMALOUS WESTERLY FLOW ENHANCE PROBABILITIES FOR BELOW MEDIAN PRECIPITATION
FOR THE SOUTHERN PORTION OF THE CONUS FROM THE EASTERN SOUTHERN PLAINS TO THE
MID-ATLANTIC COAST. THE TROUGH OVER THE WEST-CENTRAL CONUS FAVORS ABOVE MEDIAN
PRECIPITATION FROM THE SOUTHWEST CONUS NORTHEASTWARD TO THE UPPER MISSISSIPPI
VALLEY/GREAT LAKES, AND EASTWARD TO THE NORTHEAST CONUS. THE RIDGE BUILDING
OVER THE WESTERN CONUS INDICATES A CHANGE TO THE VERY WET PATTERN SEEN THERE IN
RECENT WEEKS AND ENHANCES PROBABILITIES FOR BELOW MEDIAN PRECIPITATION FOR THE
NORTHWEST U.S. ANOMALOUS SOUTHERLY FLOW TILTS THE ODDS TO ABOVE MEDIAN
PRECIPITATION FOR THE ALEUTIANS, WESTERN, CENTRAL AND SOUTHEASTERN ALASKA, AND
THE ALASKA PANHANDLE.

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, 10% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, 15% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 10, 10% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 10% OF
YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO GOOD AGREEMENT AMONG THE MODEL SOLUTIONS AND THE VARIOUS SURFACE TOOLS,
OFFSET BY THE EXPECTED PROGRESSION OF THE LONGWAVE PATTERN

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:
19890125 - 20070116 - 19900118 - 19740123 - 19840124


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:
19890125 - 20070118 - 19900117 - 19891231 - 19841231


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 22 - 26 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 24 - 30 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   N    B     WYOMING     B    N
UTAH        B    N     ARIZONA     B    A     COLORADO    B    A
NEW MEXICO  B    A     N DAKOTA    N    A     S DAKOTA    N    A
NEBRASKA    N    A     KANSAS      N    A     OKLAHOMA    N    B
N TEXAS     N    B     S TEXAS     N    B     W TEXAS     B    N
MINNESOTA   A    A     IOWA        A    A     MISSOURI    N    N
ARKANSAS    N    B     LOUISIANA   N    B     WISCONSIN   A    A
ILLINOIS    A    N     MISSISSIPPI N    B     MICHIGAN    A    A
INDIANA     A    N     OHIO        A    A     KENTUCKY    A    B
TENNESSEE   N    B     ALABAMA     N    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    N     W VIRGINIA  A    N
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    B
N CAROLINA  A    B     S CAROLINA  N    B     GEORGIA     N    B
FL PNHDL    N    B     FL PENIN    B    B     AK N SLOPE  N    A
AK ALEUTIAN N    A     AK WESTERN  N    A     AK INT BSN  N    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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