Prognostic Meteorological Discussion
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FXUS06 KWBC 301920
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT THU MARCH 30 2017

6-10 DAY OUTLOOK FOR APR 05 - 09 2017

TODAY`S DYNAMICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN PREDICTED OVER NORTH AMERICA. TROUGHS ARE EXPECTED OVER THE
THE GULF OF ALASKA AND THE EASTERN CONUS, WHILE RIDGES ARE FORECAST OVER PARTS
OF EASTERN ALASKA AND WESTERN CANADA, AND OVER PARTS OF THE WESTERN CONUS.
COMPARED TO YESTERDAYS SOLUTIONS, TODAY`S MODELS PREDICT A MUCH DEEPER TROUGH
IN THE EASTERN U.S.. THIS ALIGNS WITH TELECONNECTIONS OFF OF THE NEGATIVE
HEIGHT ANOMALY CENTER IN THE EASTERN PACIFIC, WHICH ALSO FAVORS BELOW NORMAL
HEIGHTS IN THE EAST. TODAY`S MANUAL BLEND DEPICTS NEGATIVE 500-HPA HEIGHT
ANOMALIES OVER MOST OF ALASKA AND THE EASTERN U.S., AND POSITIVE 500-HPA HEIGHT
ANOMALIES OVER THE WESTERN CONUS.

TROUGHING OVER PARTS OF WESTERN ALASKA FAVORS BELOW NORMAL TEMPERATURES FOR
COASTAL AREAS OF WESTERN ALASKA AND THE ALEUTIANS, WHILE RIDGING OVER PARTS OF
EASTERN ALASKA FAVORS ABOVE NORMAL TEMPERATURES FOR MUCH OF THE REMAINDER OF
THE STATE. AN ANOMALOUS RIDGE OVER THE WESTERN CONUS INCREASES THE LIKELIHOOD
OF ABOVE NORMAL TEMPERATURES FOR MOST OF THE WESTERN TWO THIRDS OF THE CONUS,
EXCEPT FOR THE PACIFIC NORTHWEST, WHERE PREDICTED NEAR NORMAL HEIGHTS AND AN
EXPECTED WET PATTERN FAVOR NEAR NORMAL TEMPERATURES INSTEAD. AN ANTICIPATED
DEEPER THAN NORMAL TROUGH IN THE EASTERN U.S. FAVORS NEAR NORMAL TEMPERATURES
FOR MUCH OF THE EASTERN U.S., EXCEPT FOR THE GULF COAST AND FLORIDA WHERE
SURFACE HIGH PRESSURE AND LESS CLOUDINESS INCREASE CHANCES FOR ABOVE NORMAL
TEMPERATURES. DESPITE THE EXPECTATION OF BELOW NORMAL HEIGHTS, BELOW NORMAL
TEMPERATURES ARE NOT FAVORED IN THE EASTERN U.S. DUE TO PREDICTED POSITIVE
TEMPERATURE ANOMALIES IN THE FIRST COUPLE OF DAYS OF THE PERIOD, AND SOME
DISCREPANCIES BETWEEN THE LATEST BIAS-CORRECTED GFS AND ECMWF ENSEMBLE
TEMPERATURE TOOLS.


A CHANCE FOR SOME PRECIPITATION FROM A FEW STORM SYSTEMS IN THE GULF OF ALASKA
SLIGHTLY INCREASES THE CHANCES FOR ABOVE MEDIAN PRECIPITATION IN EASTERN
ALASKA, MAINLY BECAUSE MUCH OF ALASKA IS NORMALLY DRY AT THIS TIME OF YEAR.
WITH THE TROUGH FORECAST TO BE CENTERED SOUTH OF ALASKA, THE WESTERN HALF OF
ALASKA IS EXPECTED TO REMAIN DRY AS STORM SYSTEMS ROTATE AROUND TO THE
SOUTHEAST SIDE OF THE TROUGH. THIS FAVORS BELOW MEDIAN PRECIPITATION FOR PARTS
OF WESTERN ALASKA AND THE ALEUTIANS. SEVERAL STORM SYSTEMS ARE FORECAST TO MOVE
ONSHORE IN THE WESTERN CONUS, STRONGLY FAVORING ABOVE MEDIAN PRECIPITATION FOR
PARTS OF THE WEST COAST INTO THE GREAT BASIN. A STORM SYSTEM FORECAST TO MOVE
ACROSS THE GREAT LAKES REGION AND INTO THE NORTHEAST, TOWARDS THE END OF THE
PERIOD, ENHANCES THE LIKELIHOOD OF ABOVE MEDIAN PRECIPITATION FOR THOSE AREAS.
BELOW MEDIAN PRECIPITATION IS FAVORED DOWNSTREAM OF THE RIDGE FORECAST OVER THE
WESTERN U.S.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 60% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, AND 40% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8


FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: NEAR AVERAGE, 3 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG THE DYNAMICAL MODELS ON THE FORECAST 500-HPA HEIGHT
PATTERN, OFFSET BY A RELATIVELY SIGNIFICANT CHANGE IN THE FORECAST STRENGTH OF
THE EASTERN TROUGH FROM YESTERDAY, AND SOME DISAGREEMENT AMONG THE TEMPERATURE
TOOLS IN THE EASTERN U.S.

8-14 DAY OUTLOOK FOR APR 07 - 13 2017

THE 500-HPA HEIGHT PATTERN FORECAST IN THE WEEK-2 PERIOD IS SHIFTED A BIT EAST
FROM THE 6-10 DAY PERIOD, AND LESS AMPLIFIED. THIS IS CONSISTENT WITH THE
INCREASE IN UNCERTAINTY DURING THE WEEK-2 PERIOD. THE PROBABILISTIC TEMPERATURE
FORECAST FOR THE WEEK-2 PERIOD IS SIMILAR TO THE 6-10 DAY PERIOD, WITH A COUPLE
OF EXCEPTIONS. MODELS ARE PREDICTING MORE TROUGH ENERGY ENTERING THE WEST COAST
DURING THE WEEK-2 PERIOD, INCREASING CHANCES FOR BELOW NORMAL TEMPERATURES FOR
PARTS OF THE WEST. AS THE PATTERN IS SHIFTED EASTWARD, THE AREAS OF ABOVE
NORMAL TEMPERATURES ARE ALSO SHIFTED EASTWARD.

THERE ARE SOME DIFFERENCES IN THE PROBABILISTIC PRECIPITATION FORECAST AS WELL.
STORM SYSTEM ACTIVITY IS FORECAST TO BE RELATIVELY QUIET OVER ALASKA DURING THE
WEEK-2 PERIOD, LEADING TO NEAR MEDIAN PRECIPITATION FOR THE STATE, EXCEPT FOR
THE SOUTH COAST AND ALEUTIANS. HERE THE TYPICAL PRECIPITATION AMOUNTS ARE
HIGHER, SO A RELATIVE LULL IN STORM SYSTEMS EQUATES TO BELOW MEDIAN
PRECIPITATION. WITH MORE TROUGH ENERGY PREDICTED TO ENTER THE WESTERN CONUS,
ABOVE MEDIAN PRECIPITATION IS FAVORED FURTHER EAST, EXTENDING INTO THE NORTHERN
PLAINS. WITH THE EASTERN STORM SYSTEM EXPECTED TO EXIT THE AREA BY THE WEEK-2
PERIOD, NEAR TO BELOW MEDIAN PRECIPITATION IS FAVORED FOR THE EASTERN U.S. FOR
THE WEEK-2 PERIOD.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 70% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, AND 30% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY
11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 OUT OF 5, DUE TO
FAIR AGREEMENT AMONG THE DYNAMICAL MODELS ON THE FORECAST 500-HPA HEIGHT
PATTERN AND AMONG THE TOOLS.

FORECASTER: MIKE C

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
APRIL 20

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:
19950316 - 19840318 - 20040329 - 19840323 - 20030320


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:
19840321 - 19950315 - 20040328 - 20030320 - 20000321


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 05 - 09 2017

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 07 - 13 2017

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