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FXUS06 KWBC 242001
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI FEBRUARY 24 2017

6-10 DAY OUTLOOK FOR MAR 02 - 06 2017

TODAY`S DYNAMICAL MODELS REMAIN IN GOOD AGREEMENT ON AN AMPLIFIED FORECAST
PATTERN OVER NORTH AMERICA AND UPSTREAM OVER THE NORTH PACIFIC. A CLASSIC
OMEGA-TYPE BLOCKING PATTERN IS FORECAST OVER THE NORTH PACIFIC, WITH THE
LARGEST POSITIVE HEIGHT ANOMALIES CENTERED OVER NORTHEAST ASIA. DOWNSTREAM OVER
WESTERN NORTH AMERICA, THERE IS A STRONG CONFLUENCE ZONE WITH NEGATIVE HEIGHT
ANOMALIES OVER NORTHWEST CANADA AND ANOMALOUS RIDGING FORECAST JUST OFF THE
CALIFORNIA COAST. A BROAD ANOMALOUS TROUGH EXTENDS THROUGH THE GREAT LAKES TO A
CLOSED LOW FORECAST OVER THE NORTHWEST ATLANTIC. THIS NEGATIVE HEIGHT ANOMALY
FORECAST OVER THE NORTH ATLANTIC COMBINED WITH A CLOSED HIGH OVER GREENLAND
CONSTITUTES ANOTHER PROMINENT BLOCKING PATTERN.

THE TEMPERATURE OUTLOOK FOR THIS PERIOD REFLECTS A PREDICTED PATTERN CHANGE
FROM RECENT CONDITIONS OVER MUCH OF THE NORTH-CENTRAL AND NORTHEASTERN CONUS. A
STORM SYSTEM IS FORECAST TO TRACK THROUGH THE GREAT LAKES JUST BEFORE OR AT THE
VERY BEGINNING OF THE PERIOD. IN THE WAKE OF THE ASSOCIATED COLD FRONT, THE
PATTERN IS EXPECT TO BECOME DISTINCTLY COLDER RELATIVE TO NORMAL OVER THE
NORTH-CENTRAL AND NORTHEASTERN CONUS, AT LEAST COMPARED TO THE MID-TO-LATE
FEBRUARY PERIOD. ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE SOUTHERN TIER OF
THE CONUS UNDER POSITIVE 500-HPA HEIGHT ANOMALIES, WITH A MAXIMUM IN
PROBABILITIES OVER THE CENTRAL/SOUTHERN PLAINS ASSOCIATED WITH RETURN FLOW
BEING MORE LIKELY DURING THE PERIOD. BELOW-NORMAL TEMPERATURES ARE FAVORED OVER
THE NORTHWEST, THOUGH SOME MODERATION IS POSSIBLE LATE IN THE PERIOD. THE MEAN
SEA-LEVEL PRESSURE FORECASTS FROM THE VARIOUS MODELS SUGGEST THAT THE
PERIOD-AVERAGE FRONTAL ZONE IS LIKELY TO BE DRAPED ACROSS THE GREAT LAKES AND
NORTHEAST, WHERE TEMPERATURE PROBABILITIES ARE NOTABLY LOW AMPLITUDE.

THE PRECIPITATION OUTLOOK OVER THE CONUS REMAINS CONSISTENT WITH RECENT DAYS.
MORE ACTIVE WEATHER IS LIKELY ACROSS THE NORTHERN TIER WHERE THE BAROCLINICITY
IS EXPECTED TO BE THE GREATEST. THIS NORTHWARD SHIFT IN THE STORM TRACK COMES
AT THE EXPENSE OF PRECIPITATION OVER THE CENTRAL AND SOUTHWESTERN CONUS. ODDS
OF BELOW-MEDIAN PRECIPITATION ARE HIGHEST OVER THE SOUTHWEST, IMMEDIATELY
DOWNSTREAM OF FORECAST ANOMALOUS RIDGING. ABOVE-MEDIAN RAINFALL IS MORE LIKELY
ACROSS PARTS OF THE GULF COAST AND SOUTHEAST WHERE A STALLED COLD FRONT IS
LIKELY TO SERVE AS A FOCAL POINT FOR ACTIVE WEATHER.

THE FORECAST FOR ALASKA IS DOMINATED BY THE BLOCK FORECAST OVER FAR
NORTHEASTERN ASIA. ANOMALOUS NORTHERLY FLOW AND SURFACE HIGH PRESSURE STRONGLY
SUGGEST A COLD AND DRY PERIOD RELATIVE TO NORMAL FOR MUCH OF THE STATE.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 0Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 30% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8, AND
50% OF TODAY`S 0Z EUROPEAN 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, OFFSET BY SOME UNCERTAINTY IN THE OUTLOOK
OVER THE NORTHEASTERN QUARTER OF THE CONUS.

8-14 DAY OUTLOOK FOR MAR 04 - 10 2017

THE WEEK-2 MANUAL HEIGHT BLEND IS LARGELY SIMILAR TO THAT FOR THE 6-10 DAY
PERIOD. THE LARGEST CHANGE FROM THE EARLY PERIOD OVER NORTH AMERICA IS THAT THE
LARGEST NEGATIVE HEIGHT ANOMALIES ARE CENTERED OVER EASTERN NEW ENGLAND AND
EXTEND EASTWARD INTO THE NORTH ATLANTIC WHERE A FORECAST BLOCKING PATTERN
REMAINS INTACT. ANOMALOUS RIDGING ALONG THE WEST COAST NOW EXTENDS SLIGHTLY
FARTHER NORTHWARD INTO THE INTERIOR NORTHWEST AND NORTH OF THE 50TH PARALLEL.
AS A RESULT, THE TEMPERATURE OUTLOOK SHOWS A FAIRLY SIZABLE TILT TOWARD
COLDER-THAN-NORMAL TEMPERATURES OVER THE MIDWEST, GREAT LAKES, AND MUCH OF THE
EAST COAST, COMPARED TO THE 6-10 DAY PERIOD. LIKEWISE SOME MODERATION IS
FORECAST OVER THE NORTHWEST. THE REFORECAST-CALIBRATED FORECAST TOOLS ARE
SLIGHTLY PREFERRED TODAY COMPARED TO TOOLS RELYING ON SHORT TERM BIAS
CORRECTION. THE RECENT RECORD WARMTH OVER PARTS OF THE EAST-CENTRAL CONUS IS
LIKELY TO RESULT IN SHORT TERM BIASES THAT ARE HIGHER THAN THE ACTUAL
SYSTEMATIC ERROR CONSIDERING A BROAD PATTERN CHANGE IS FORECAST.

THE PRECIPITATION OUTLOOK IS VERY SIMILAR TO THE 6-10 DAY OUTLOOK, WITH THE
MOST NOTABLE CHANGE BEING A TILT TOWARD DRIER CONDITIONS OVER THE MID-ATLANTIC
AND NORTHEAST. THIS REGION IS MORE LIKELY TO BE UNDER THE INFLUENCE OF
ANOMALOUS NORTHERLY SURFACE WINDS, WITH SURFACE HIGH PRESSURE CENTERED OVER THE
CENTRAL CONUS.

THE FORECAST CIRCULATION OVER ALASKA IS AGAIN DOMINATED BY THE FORECAST
BLOCKING PATTERN UPSTREAM. AS A RESULT, RELATIVELY COLD AND DRY CONDITIONS ARE
MORE LIKELY, WITH PROBABILITIES SLIGHTLY DAMPED FROM THE MORE CONFIDENT 6-10
DAY PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 30% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, AND 50% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11


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

FORECASTER: STEPHEN BAXTER

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:
19520217 - 20010208 - 19510219 - 19960225 - 19510227


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:
20090306 - 20010207 - 19620216 - 19960225 - 20010212


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 02 - 06 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAR 04 - 10 2017

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