Prognostic Meteorological Discussion
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FXUS06 KWBC 212001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST TUE FEBRUARY 21 2017

6-10 DAY OUTLOOK FOR FEB 27 - MAR 03, 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS REMAIN IN GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN PREDICTED OVER NORTH AMERICA. A BLOCKING PATTERN IS
FORECAST OVER THE NORTHEAST PACIFIC WITH A BROAD DOWNSTREAM TROUGH OVER
WEST-CENTRAL NORTH AMERICA. WEST-SOUTHWESTERLY ZONAL FLOW IS PREDICTED OVER THE
EASTERN SEABOARD EXTENDING INTO THE WESTERN ATLANTIC. TODAY`S 500-HPA HEIGHT
BLEND OF AVAILABLE ENSEMBLE MODELS INDICATES ABOVE NORMAL HEIGHTS ACROSS MOST
OF THE SOUTHEASTERN CONUS AND WESTERN ALASKA, WHILE BELOW NORMAL HEIGHTS ARE
EXPECTED OVER MOST OF THE WESTERN CONUS AND EASTERN ALASKA. ENSEMBLE SPAGHETTI
DIAGRAMS INDICATE LOW ENSEMBLE SPREAD ACROSS THE MAJORITY OF THE FORECAST
DOMAIN. THE GREATEST WEIGHT FOR THE BLENDED HEIGHT FORECAST WAS GIVEN TO THE
06Z GFS ENSEMBLE MEAN SOLUTION BASED ON CONSIDERATIONS OF RECENT SKILL AND
ANALOG CORRELATIONS, WHICH MEASURE HOW CLOSELY THE FORECAST PATTERN MATCHES
CASES THAT HAVE OCCURRED IN THE PAST.

BELOW NORMAL HEIGHTS AND A PREDICTED TROUGH OVER THE WESTERN CONUS TILT THE
ODDS TO BELOW NORMAL TEMPERATURES FOR THE WESTERN CONUS AND PARTS OF THE
NORTHERN PLAINS. ABOVE NORMAL HEIGHTS AND STRONG SOUTHWESTERLY FLOW ENHANCE
PROBABILITIES FOR ABOVE NORMAL TEMPERATURES FOR THE EASTERN HALF OF THE CONUS,
AND PARTS OF THE CENTRAL AND SOUTHERN PLAINS.

THE BROAD TROUGH FORECAST OVER THE WEST-CENTRAL CONUS AS WELL AS AN ASSOCIATED
ACTIVE STORM TRACK FAVOR ABOVE MEDIAN PRECIPITATION FOR THE WESTERN CONUS.
ABOVE NORMAL HEIGHTS OVER THE EASTERN SEABOARD TILT THE ODDS TO BELOW MEDIAN
PRECIPITATION FOR FLORIDA. ABOVE MEDIAN PRECIPITATION IS FAVORED FOR MOST OF
THE EASTERN CONUS, WHILE BELOW MEDIAN IS INDICATED FOR PARTS OF THE SOUTHERN
PLAINS AND THE SOUTHERN ROCKIES, CONSISTENT WITH PRECIPITATION ESTIMATES FROM
THE GEFS AND ECMWF ENSEMBLE MEMBERS.

THE FORECAST BLOCKING PATTERN OVER THE NORTHEAST PACIFIC IS EXPECTED TO LEAD TO
ANOMALOUS NORTHWESTERLY MID-LEVEL FLOW OVER ALASKA, WHICH FAVORS BELOW NORMAL
TEMPERATURE OVER MOST OF ALASKA. ABOVE-MEDIAN PRECIPITATION IS STRONGLY FAVORED
OVER MUCH OF MAINLAND ALASKA, WHILE BELOW-MEDIAN PRECIPITATION IS FAVORED OVER
THE SOUTH COAST OF ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 10% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 40% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, 10%
OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8, 20% OF TODAY`S 0Z EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 8, AND 20% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG FORECAST TOOLS.

8-14 DAY OUTLOOK FOR MAR 01 - 07 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.
THE 500-HPA PATTERN FORECAST FOR THE WEEK-2 PERIOD IS SIMILAR TO THE 6-10 DAY
PERIOD, WITH A BLOCKING PATTERN OVER THE NORTHEAST PACIFIC, AND A BROAD
DOWNSTREAM TROUGH OVER THE WESTERN CONUS, AS WELL AS WEST-SOUTHWESTERLY ZONAL
FLOW OVER THE EASTERN SEABOARD. ENSEMBLE SPAGHETTI DIAGRAMS INDICATE LOW
ENSEMBLE SPREAD ACROSS THE MAJORITY OF THE FORECAST DOMAIN.

THE RESULTING TEMPERATURE OUTLOOK IS VERY SIMILAR TO THAT FOR THE 6-10 DAY
PERIOD. BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN CONUS AND THE
NORTHERN PLAINS, PARTS OF THE CENTRAL PLAINS, AS WELL AS MOST OF ALASKA. ABOVE
NORMAL TEMPERATURES ARE INDICATED FOR THE EASTERN HALF OF THE CONUS, AND PARTS
OF THE CENTRAL AND SOUTHERN PLAINS.

THE TROUGH FORECAST OVER THE WESTERN COUNS FAVORS ABOVE MEDIAN PRECIPITATION
FOR THE NORTHWESTERN CONUS. ABOVE NORMAL HEIGHTS OVER THE EASTERN SEABOARD TILT
THE ODDS TO BELOW MEDIAN PRECIPITATION FOR MOST OF FLORIDA. ABOVE MEDIAN
PRECIPITATION IS FAVORED FOR MOST OF THE EASTERN CONUS, WHILE BELOW MEDIAN IS
INDICATED FOR PARTS OF CALIFORNIA, CONSISTENT WITH PRECIPITATION ESTIMATES FROM
THE GEFS AND ECMWF ENSEMBLE MEMBERS.

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, 40% OF TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11, 30% OF TODAY`S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 10% OF TODAY`S 0Z CANADIAN
ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO GOOD AGREEMENT AMONG FORECAST TOOLS.

FORECASTER: LUKE HE

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
MARCH 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:
20040225 - 19780207 - 19920201 - 19980214 - 19690213


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:
20040225 - 19920131 - 19990212 - 19690212 - 19780206


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 27 - MAR 03, 2017

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    A     OREGON      B    A     NRN CALIF   B    A
SRN CALIF   B    A     IDAHO       B    A     NEVADA      B    A
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    A
UTAH        B    A     ARIZONA     B    A     COLORADO    N    N
NEW MEXICO  A    B     N DAKOTA    N    A     S DAKOTA    N    A
NEBRASKA    N    N     KANSAS      A    B     OKLAHOMA    A    B
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    B
MINNESOTA   N    A     IOWA        A    A     MISSOURI    A    A
ARKANSAS    A    A     LOUISIANA   A    A     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    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    A
MARYLAND    A    A     DELAWARE    A    A     VIRGINIA    A    A
N CAROLINA  A    A     S CAROLINA  A    A     GEORGIA     A    A
FL PNHDL    A    N     FL PENIN    A    B     AK N SLOPE  B    A
AK ALEUTIAN N    B     AK WESTERN  B    A     AK INT BSN  B    A
AK S INT    B    N     AK SO COAST B    B     AK PNHDL    B    B



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 01 - 07 2017

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  B    A     OREGON      B    A     NRN CALIF   B    N
SRN CALIF   B    N     IDAHO       B    A     NEVADA      B    N
W MONTANA   B    A     E MONTANA   B    A     WYOMING     B    A
UTAH        B    N     ARIZONA     B    N     COLORADO    B    N
NEW MEXICO  N    N     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    B    N     KANSAS      N    N     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    N
MINNESOTA   N    A     IOWA        N    A     MISSOURI    A    N
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   N    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    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    A
MARYLAND    A    A     DELAWARE    A    A     VIRGINIA    A    A
N CAROLINA  A    A     S CAROLINA  A    A     GEORGIA     A    A
FL PNHDL    A    N     FL PENIN    A    B     AK N SLOPE  N    A
AK ALEUTIAN N    B     AK WESTERN  B    B     AK INT BSN  B    N
AK S INT    B    B     AK SO COAST B    B     AK PNHDL    B    B

                           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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