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000
FXUS01 KWBC 292037
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
336 PM EST THU JAN 29 2015

VALID 00Z FRI JAN 30 2015 - 00Z SUN FEB 01 2015

...MORE SNOW ON THE WAY FOR THE GREAT LAKES TO THE NORTHEAST...

...WIDESPREAD RAIN AND SNOW EXPECTED ACROSS THE SOUTHWEST U.S....

ANOTHER ROUND OF WINTRY WEATHER IS ON THE WAY FROM THE GREAT LAKES
TO NEW ENGLAND AS A CLIPPER SYSTEM RACES ACROSS THE NORTHEAST ON
FRIDAY. LIGHT TO MODERATE SNOW ACROSS THE GREAT LAKES AREA THIS
AFTERNOON WILL SLIDE INTO THE LOWER LAKES AND NEW ENGLAND BY
TONIGHT. ACCORDING TO THE WPC WINTER WEATHER GRAPHICS, MOST
LOCATIONS FROM THE LOWER LAKES INTO NEW ENGLAND SHOULD SEE LESS
THAN ABOUT SIX INCHES, EXCEPT ACROSS MAINE, WHERE ACCUMULATIONS AS
HIGH AS A FOOT OR MORE ARE POSSIBLE. FARTHER SOUTH ACROSS THE
MID-ATLANTIC, A MIXTURE OF RAIN AND SNOW IS LIKELY AND BEHIND THE
SYSTEM, THE WEEKEND WILL BEGIN VERY CHILLY WITH TEMPERATURES BELOW
AVERAGE AS SURFACE HIGH PRESSURE TAKES OVER.

ACROSS THE SOUTHWEST AND FOUR CORNERS REGION, CONDITIONS WILL
CONTINUE TO BE INCREASINGLY WET THIS EVENING AND INTO THE WEEKEND
AS AN UPPER LEVEL TROUGH MOVES INLAND OVER NORTHERN MEXICO. NEAR
THE SURFACE, LOW-LEVEL WINDS WILL ADVECT PLENTY OF MOISTURE INTO
THESE AREAS, FUELING WIDESPREAD MODERATE TO HEAVY PRECIPITATION
ACROSS THE SOUTHWEST. MODERATE TO HEAVY SNOW IS EXPECTED IN THE
HIGHER TERRAIN, ESPECIALLY ACROSS NEW MEXICO, WHILE HEAVY RAIN IS
EXPECTED FARTHER SOUTH AND WEST IN THE LOWER ELEVATIONS OF
SOUTHERN NEW MEXICO AND ARIZONA. THIS PRECIPITATION IS EXPECTED TO
MOVE INTO THE SOUTHERN AND CENTRAL PLAINS BY SATURDAY MORNING
WHERE PLACES ACROSS THE TEXAS PANHANDLE INTO KANSAS COULD SEE A
RAIN/SNOW MIX, WITH PLAIN RAIN EXPECTED FARTHER SOUTH.


SANTORELLI


GRAPHICS AVAILABLE AT WWW.WPC.NCEP.NOAA.GOV
$$






000
FXUS06 KWBC 292002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST THU JANUARY 29 2015

6-10 DAY OUTLOOK FOR FEB 04 - 08 2015

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN FORECAST OVER NORTH AMERICA. TROUGHS ARE ANTICIPATED OVER
THE EASTERN TWO-THIRDS OF THE CONUS AND WESTERN ALASKA, WHILE A RIDGE IS
FORECAST OVER THE WESTERN THIRD OF CONUS EXTENDING NORTHWARD TOWARDS WESTERN
CANADA. THE GFS-BASED ENSEMBLES DEPICT THE MAIN CIRCULATION FEATURES A BIT
FURTHER EAST COMPARED TO THE ECMWF AND CANADIAN ENSEMBLES. RECENT HIGH
RESOLUTION RUNS FROM THE ECMWF ARE IN REASONABLY GOOD AGREEMENT WITH THEIR
RESPECTIVE ENSEMBLE MEANS. THE LATEST GFS HIGH RESOLUTION SOLUTIONS ARE A BIT
LESS PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES COMPARED TO THEIR
RESPECTIVE ENSEMBLE MEANS. SINCE THE ECMWF-BASED SOLUTIONS ARE MORE CONSISTENT,
THEY WERE FAVORED IN TODAYS MANUAL 500-HPA BLEND CHART.

THE ENSEMBLE SPAGHETTI CHARTS GENERALLY INDICATE VERY LOW SPREAD OVER THE
EASTERN CONUS, AND LOW TO MODERATE MODERATE SPREAD OVER THE WESTERN CONUS. THE
PNA INDEX WHICH RECENTLY HAS BEEN NEGATIVE IS FORECAST TO BE POSITIVE BY DAY 7,
AND REMAIN POSITIVE THROUGH DAY 14. THE NAO INDEX WHICH RECENTLY HAS BEEN
POSITIVE IS FORECAST TO DECREASE IN MAGNITUDE BUT REMAIN POSITIVE BY DAY 7, AND
REMAIN POSITIVE THROUGH DAY 14. TODAY`S BLENDED 500-HPA HEIGHT CHART INDICATES
NEAR TO BELOW NORMAL HEIGHTS OVER THE EASTERN HALF OF THE CONUS, AND ALASKA,
AND NEAR TO ABOVE NORMAL HEIGHTS OVER THE WESTERN HALF OF THE CONUS AND THE
WESTERN ALEUTIANS.

THE TROUGH EXPECTED OVER THE EASTERN U.S. ENHANCES PROBABILITIES FOR BELOW
NORMAL TEMPERATURES FOR MUCH FOR THE CENTRAL AND EASTERN CONUS. THE RIDGE AND
AREA OF ABOVE NORMAL HEIGHTS OVER THE WEST TILT THE ODDS TO ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE WESTERN THIRD OF THE CONUS AND PARTS OF THE
CENTRAL ROCKIES AND CENTRAL PLAINS. BELOW NORMAL HEIGHTS ENHANCE PROBABILITIES
FOR BELOW NORMAL TEMPERATURES FOR NORTHERN AND WESTERN ALASKA, WHILE ANOMALOUS
SOUTHEASTERLY FLOW FAVORS ABOVE NORMAL TEMPERATURES FOR SOUTHERN ALASKA AND THE
ALASKA PANHANDLE.

THE TROUGH OVER EASTERN NORTH AMERICA ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR FLORIDA AND COASTAL SECTIONS OF THE SOUTHEAST. SUBSIDENCE ON
THE REAR SIDE OF THE TROUGH FORECAST OVER THE EAST ENHANCES PROBABILITIES FOR
BELOW MEDIAN PRECIPITATION FOR MUCH OF THE CENTRAL AND EAST-CENTRAL CONUS.
ABOVE NORMAL HEIGHTS TILT THE ODDS TO FAVORING BELOW MEDIAN PRECIPITATION FOR
THE SOUTHWEST CONUS. A TROUGH FORECAST NEAR WESTERN ALASKA ENHANCES
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR EASTERN ALASKA, THE ALASKA
PANANDLE, AND SECTIONS OF WASHINGTON, OREGON, AND EXTREME NORTHWESTERN
CALIFORNIA. HIGH PRESSURE BUILDING NORTHWEST OF ALASKA TILTS THE ODDS TO BELOW
MEDIAN PRECIPITATION FOR PARTS OF NORTHWESTERN ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5% OF TODAY`S OPERATIONAL 0Z GFS
CENTERED ON DAY 8, 35% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
20% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 15% OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 15% OF TODAY`S 0Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 8, AND 10% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 7


MODEL OF THE DAY: 0Z ECMWF ENSEMBLE.

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE MODELS AND GOOD AGREEMENT AMONG THE TOOLS, AND
A PERSISTENT, HIGHLY AMPLIFIED PATTERN.

8-14 DAY OUTLOOK FOR FEB 06 - 12 2015

DURING THE WEEK-2 PERIOD, THE ENSEMBLE MEAN SOLUTIONS GENERALLY INDICATE A
PROGRESSION OF THE CIRCULATION PATTERN FROM THAT FORECAST FOR THE 6-10 DAY
PERIOD AS HEIGHTS RISE OVER THE NORTH-CENTRAL CONUS. THE GFS-BASED ENSEMBLE
SOLUTIONS CONTINUE TO BE MORE PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES
COMPARED TO THE ECMWF AND CANADIAN ENSEMBLES. THE 0Z HIGH RESOLUTION GFS
FORECAST IS LESS PROGRESSIVE THAN ITS CORRESPONDING ENSEMBLE MEAN. SO AS WAS
TRUE FOR THE 6-10 DAY PERIOD, THE WEEK-2 BLEND IS MORE HEAVILY WEIGHTED BY THE
ECMWF AND CANADIAN FORECASTS. A TROUGH IS ANTICIPATED OVER THE EASTERN CONUS
WHILE A RIDGE BUILDS OVER THE WEST. A TROUGH IS FORECAST OVER WESTERN ALASKA
WHILE A RIDGE IS EXPECTED OVER THE EASTERN PART OF THE STATE. THE ENSEMBLE
SPAGHETTI CHARTS GENERALLY INDICATE LOW TO MODERATE SPREAD OVER THE EASTERN
CONUS AND LARGE SPREAD OVER THE WEST.

TODAY`S WEEK-2 BLEND CHART INDICATES NEAR TO BELOW NORMAL HEIGHTS OVER THE
EASTERN THIRD OF THE CONUS AND ALASKA, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE
ANTICIPATED OVER THE WESTERN TWO THIRDS OF THE CONUS AND THE ALASKA PANHANDLE.

THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK-2 ARE
MOSTLY SIMILAR TO THOSE EXPECTED DURING THE 6-10 DAY PERIOD. ALTHOUGH, AS
HEIGHTS RISE OVER THE NORTH-CENTRAL CONUS, THE AREA OF EXPECTED BELOW NORMAL
TEMPERATURES OVER THE CENTRAL CONUS DEPICTED FOR THE 6-10 DAY PERIOD SHRINKS A
BIT AS THE AREA OF ABOVE NORMAL TEMPERATURES EXPANDS EAST/NORTHEASTWARD. JET
ENERGY IS EXPECTED TO APPROACH THE NORTHWEST CONUS. THIS LEADS TO AN EXPANSION
OF THE AREA FORECAST TO HAVE ABOVE MEDIAN PRECIPITATION. AS THE TROUGH
ANTICIPATED OVER THE EASTERN CONUS PROGRESSES TO THE NORTHEAST, THE FORECAST
AREA OF ABOVE MEDIAN PRECIPITATION ALONG THE SOUTHEAST COAST AND FLORIDA DURING
THE 6-10 DAY PERIOD IS EXPECTED TO TRANSITION TO NEAR MEDIAN PRECIPITATION FOR
WEEK-2.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S OPERATIONAL 0Z
GFS CENTERED ON DAY 11, 50% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, 20% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, 15%
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 5% OF YESTERDAY`S
12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO FAIRLY GOOD AGREEMENT AMONG THE MODELS OFFSET BY THE DIFFICULTIES IN TIMING
ASSOCIATED WITH A PROGRESSIVE CIRCULATION PATTERN AND RELATIVELY POOR AGREEMENT
AMONG THE PRECIPITATION FORECAST TOOLS.

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
FEBRUARY 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:
19540207 - 20050119 - 19760119 - 20050130 - 19870208


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:
19540207 - 20050120 - 20050129 - 19910209 - 19870209


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 04 - 08 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 06 - 12 2015

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

$$






000
FXUS06 KWBC 292002
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST THU JANUARY 29 2015

6-10 DAY OUTLOOK FOR FEB 04 - 08 2015

TODAY`S ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE 500-HPA
CIRCULATION PATTERN FORECAST OVER NORTH AMERICA. TROUGHS ARE ANTICIPATED OVER
THE EASTERN TWO-THIRDS OF THE CONUS AND WESTERN ALASKA, WHILE A RIDGE IS
FORECAST OVER THE WESTERN THIRD OF CONUS EXTENDING NORTHWARD TOWARDS WESTERN
CANADA. THE GFS-BASED ENSEMBLES DEPICT THE MAIN CIRCULATION FEATURES A BIT
FURTHER EAST COMPARED TO THE ECMWF AND CANADIAN ENSEMBLES. RECENT HIGH
RESOLUTION RUNS FROM THE ECMWF ARE IN REASONABLY GOOD AGREEMENT WITH THEIR
RESPECTIVE ENSEMBLE MEANS. THE LATEST GFS HIGH RESOLUTION SOLUTIONS ARE A BIT
LESS PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES COMPARED TO THEIR
RESPECTIVE ENSEMBLE MEANS. SINCE THE ECMWF-BASED SOLUTIONS ARE MORE CONSISTENT,
THEY WERE FAVORED IN TODAYS MANUAL 500-HPA BLEND CHART.

THE ENSEMBLE SPAGHETTI CHARTS GENERALLY INDICATE VERY LOW SPREAD OVER THE
EASTERN CONUS, AND LOW TO MODERATE MODERATE SPREAD OVER THE WESTERN CONUS. THE
PNA INDEX WHICH RECENTLY HAS BEEN NEGATIVE IS FORECAST TO BE POSITIVE BY DAY 7,
AND REMAIN POSITIVE THROUGH DAY 14. THE NAO INDEX WHICH RECENTLY HAS BEEN
POSITIVE IS FORECAST TO DECREASE IN MAGNITUDE BUT REMAIN POSITIVE BY DAY 7, AND
REMAIN POSITIVE THROUGH DAY 14. TODAY`S BLENDED 500-HPA HEIGHT CHART INDICATES
NEAR TO BELOW NORMAL HEIGHTS OVER THE EASTERN HALF OF THE CONUS, AND ALASKA,
AND NEAR TO ABOVE NORMAL HEIGHTS OVER THE WESTERN HALF OF THE CONUS AND THE
WESTERN ALEUTIANS.

THE TROUGH EXPECTED OVER THE EASTERN U.S. ENHANCES PROBABILITIES FOR BELOW
NORMAL TEMPERATURES FOR MUCH FOR THE CENTRAL AND EASTERN CONUS. THE RIDGE AND
AREA OF ABOVE NORMAL HEIGHTS OVER THE WEST TILT THE ODDS TO ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE WESTERN THIRD OF THE CONUS AND PARTS OF THE
CENTRAL ROCKIES AND CENTRAL PLAINS. BELOW NORMAL HEIGHTS ENHANCE PROBABILITIES
FOR BELOW NORMAL TEMPERATURES FOR NORTHERN AND WESTERN ALASKA, WHILE ANOMALOUS
SOUTHEASTERLY FLOW FAVORS ABOVE NORMAL TEMPERATURES FOR SOUTHERN ALASKA AND THE
ALASKA PANHANDLE.

THE TROUGH OVER EASTERN NORTH AMERICA ENHANCES PROBABILITIES FOR ABOVE MEDIAN
PRECIPITATION FOR FLORIDA AND COASTAL SECTIONS OF THE SOUTHEAST. SUBSIDENCE ON
THE REAR SIDE OF THE TROUGH FORECAST OVER THE EAST ENHANCES PROBABILITIES FOR
BELOW MEDIAN PRECIPITATION FOR MUCH OF THE CENTRAL AND EAST-CENTRAL CONUS.
ABOVE NORMAL HEIGHTS TILT THE ODDS TO FAVORING BELOW MEDIAN PRECIPITATION FOR
THE SOUTHWEST CONUS. A TROUGH FORECAST NEAR WESTERN ALASKA ENHANCES
PROBABILITIES FOR ABOVE MEDIAN PRECIPITATION FOR EASTERN ALASKA, THE ALASKA
PANANDLE, AND SECTIONS OF WASHINGTON, OREGON, AND EXTREME NORTHWESTERN
CALIFORNIA. HIGH PRESSURE BUILDING NORTHWEST OF ALASKA TILTS THE ODDS TO BELOW
MEDIAN PRECIPITATION FOR PARTS OF NORTHWESTERN ALASKA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 5% OF TODAY`S OPERATIONAL 0Z GFS
CENTERED ON DAY 8, 35% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
20% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, 15% OF TODAY`S
OPERATIONAL 0Z ECMWF CENTERED ON DAY 8, 15% OF TODAY`S 0Z CANADIAN ENSEMBLE
MEAN CENTERED ON DAY 8, AND 10% OF YESTERDAY`S 12Z CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 7


MODEL OF THE DAY: 0Z ECMWF ENSEMBLE.

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT AMONG THE MODELS AND GOOD AGREEMENT AMONG THE TOOLS, AND
A PERSISTENT, HIGHLY AMPLIFIED PATTERN.

8-14 DAY OUTLOOK FOR FEB 06 - 12 2015

DURING THE WEEK-2 PERIOD, THE ENSEMBLE MEAN SOLUTIONS GENERALLY INDICATE A
PROGRESSION OF THE CIRCULATION PATTERN FROM THAT FORECAST FOR THE 6-10 DAY
PERIOD AS HEIGHTS RISE OVER THE NORTH-CENTRAL CONUS. THE GFS-BASED ENSEMBLE
SOLUTIONS CONTINUE TO BE MORE PROGRESSIVE WITH THE MAIN CIRCULATION FEATURES
COMPARED TO THE ECMWF AND CANADIAN ENSEMBLES. THE 0Z HIGH RESOLUTION GFS
FORECAST IS LESS PROGRESSIVE THAN ITS CORRESPONDING ENSEMBLE MEAN. SO AS WAS
TRUE FOR THE 6-10 DAY PERIOD, THE WEEK-2 BLEND IS MORE HEAVILY WEIGHTED BY THE
ECMWF AND CANADIAN FORECASTS. A TROUGH IS ANTICIPATED OVER THE EASTERN CONUS
WHILE A RIDGE BUILDS OVER THE WEST. A TROUGH IS FORECAST OVER WESTERN ALASKA
WHILE A RIDGE IS EXPECTED OVER THE EASTERN PART OF THE STATE. THE ENSEMBLE
SPAGHETTI CHARTS GENERALLY INDICATE LOW TO MODERATE SPREAD OVER THE EASTERN
CONUS AND LARGE SPREAD OVER THE WEST.

TODAY`S WEEK-2 BLEND CHART INDICATES NEAR TO BELOW NORMAL HEIGHTS OVER THE
EASTERN THIRD OF THE CONUS AND ALASKA, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE
ANTICIPATED OVER THE WESTERN TWO THIRDS OF THE CONUS AND THE ALASKA PANHANDLE.

THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK-2 ARE
MOSTLY SIMILAR TO THOSE EXPECTED DURING THE 6-10 DAY PERIOD. ALTHOUGH, AS
HEIGHTS RISE OVER THE NORTH-CENTRAL CONUS, THE AREA OF EXPECTED BELOW NORMAL
TEMPERATURES OVER THE CENTRAL CONUS DEPICTED FOR THE 6-10 DAY PERIOD SHRINKS A
BIT AS THE AREA OF ABOVE NORMAL TEMPERATURES EXPANDS EAST/NORTHEASTWARD. JET
ENERGY IS EXPECTED TO APPROACH THE NORTHWEST CONUS. THIS LEADS TO AN EXPANSION
OF THE AREA FORECAST TO HAVE ABOVE MEDIAN PRECIPITATION. AS THE TROUGH
ANTICIPATED OVER THE EASTERN CONUS PROGRESSES TO THE NORTHEAST, THE FORECAST
AREA OF ABOVE MEDIAN PRECIPITATION ALONG THE SOUTHEAST COAST AND FLORIDA DURING
THE 6-10 DAY PERIOD IS EXPECTED TO TRANSITION TO NEAR MEDIAN PRECIPITATION FOR
WEEK-2.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 10% OF TODAY`S OPERATIONAL 0Z
GFS CENTERED ON DAY 11, 50% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, 20% OF YESTERDAY`S 12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10, 15%
OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 5% OF YESTERDAY`S
12Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO FAIRLY GOOD AGREEMENT AMONG THE MODELS OFFSET BY THE DIFFICULTIES IN TIMING
ASSOCIATED WITH A PROGRESSIVE CIRCULATION PATTERN AND RELATIVELY POOR AGREEMENT
AMONG THE PRECIPITATION FORECAST TOOLS.

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
FEBRUARY 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:
19540207 - 20050119 - 19760119 - 20050130 - 19870208


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:
19540207 - 20050120 - 20050129 - 19910209 - 19870209


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 04 - 08 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR FEB 06 - 12 2015

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

$$





000
FXCA20 KWBC 291905
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
205 PM EST THU JAN 29 2015

DISCUSSION FROM JANUARY 29/00UTC: DEEP MID LEVEL TROUGH ON THE
SOUTHERN STREAM EXTENDS ACROSS THE BAJA PENINSULA TO THE TROPICAL
PACIFIC. THIS TROUGH IS TO PRESS AGAINST A RIDGE TO THE EAST...AND
IN THIS PROCESS IT IS TO THEN SHEAR SHORT WAVE ENERGY ACROSS BAJA
PENINSULA-SONORA/CHIHUAHUA IN NORTHWEST MEXICO. THE HIGH AMPLITUDE
TROUGH IS TO INTERACT WITH THE ITCZ TO THE SOUTH...DRAWING DEEP
MOISTURE ACROSS THE BAJA PENINSULA/NORTHWEST STATES OF MEXICO.
STRONG CYCLONIC VORTICITY ADVECTION WILL COMBINE WITH THE HIGH
TERRAIN OF THE SIERRA MADRE TO RESULT IN AREAS OF ORGANIZED HEAVY
CONVECTION. ACROSS NORTHWEST MEXICO EXPECTING RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-30MM THROUGH FRIDAY MORNING...AND
15-20MM/DAY AND MAXIMA OF 25-50MM ON FRIDAY TO SATURDAY. EARLY ON
SATURDAY FOCUS OF THE CONVECTION SHIFTS TO SONORA MEXICO...WHERE
WE ALSO EXPECT RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
25-50MM. OTHER CONVECTION IS TO THEN BUILD EAST ACROSS THE
NORTH-CENTRAL TO NORTHEASTERN STATES OF MEXICO...WITH ACCUMULATION
OF 00-05MM/DAY AND MAXIMA OF 10MM.

MID/UPPER LEVEL RIDGE PATTERN IS TO INITIALLY CONFINE TO
MEXICO-NORTHERN CENTRAL AMERICA...WHILE ANCHORING ON A CLOSED HIGH
OVER COLIMA/NAYARIT TO THE SOUTHWEST OF MEXICO. THROUGH SATURDAY
MORNING THE RIDGE RELOCATES TO THE CENTRAL CARIBBEAN AS IT YIELDS
TO THE DEEP SOUTHERN STREAM TROUGH. THIS IS TO THEN BECOME THE
DOMINANT FEATURE ACROSS THE CARIBBEAN BASIN LATER DURING THE
WEEKEND. AS THE RIDGE MOVES TO THE EAST...CAP INVERSION OVER
MEXICO IS TO WEAKEN. HOWEVER...OPPOSITE IS TRUE ACROSS THE
CARIBBEAN BASIN...WITH RIDGE TO STRENGTHEN CAP INVERSION AS THE
CYCLE PROGRESSES.

DOWNSTREAM FROM THE MID LEVEL RIDGE...OVER THE WESTERN
ATLANTIC...A BROAD POLAR TROUGH EXTENDS SOUTH TO THE NORTHERN
CARIBBEAN ISLES. THE TROUGH IS LIFTING AS IT MEANDERS TO THE
EAST-NORTHEAST...AND EARLY ON FRIDAY IT IS FORECAST TO PULL.
ASSOCIATED FRONT...MEANWHILE...IS TO EXTEND ACROSS NORTHERN
HISPANIOLA TO THE NORTHWEST CARIBBEAN. THROUGH FRIDAY MORNING IT
MEANDERS NORTH TO THE SOUTHEAST BAHAMAS/TURKS-CUBA...AND THROUGH
SATURDAY MORNING IT IS EXPECTED TO FRONTOLIZE. MEANWHILE...THIS IS
TO ENHANCE MOISTURE CONVERGENCE ACROSS NORTHERN HISPANIOLA TO
FAVOR RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-35MM.
ACROSS THE SOUTHEAST BAHAMAS/EASTERN CUBA IT IS TO THEN FAVOR
RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM.

ANOTHER TROUGH IS TO CLEAR THE EASTERN SEABOARD OF THE USA BY
MIDAFTERNOON ON FRIDAY...TO MEANDER EAST ACROSS 60W LATER ON
SATURDAY. AS RIDGE BUILDS TO THE SOUTH ACROSS THE BASIN...THE
TROUGH IS FORECAST TO BOTTOM OUT FAR TO THE NORTH. ASSOCIATED
FRONT MOVES TO THE WESTERN ATLANTIC EARLY ON FRIDAY...AND LATER IN
THE DAY IT IS TO EXTEND ACROSS CENTRAL FLORIDA TO THE NORTHERN
GULF OF MEXICO. EARLY ON SATURDAY MORNING IT IS TO ENTER THE
NORTHWEST BAHAMAS...AND DURING THE EVENING HOURS THE FRONT MOVES
TO THE CENTRAL BAHAMAS-STRAITS OF FLORIDA TO THE NORTHERN
GULF/SOUTHERN USA. BUT LACKING UPPER LEVEL SUPPORT...EARLY ON
SUNDAY MORNING THE FRONT IS TO STALL ALONG 21N/22N. BUILDING POLAR
RIDGE ACROSS THE GULF OF MEXICO IS TO THEN TRIGGER A PREFRONTAL
SHEAR LINE ACROSS THE BASIN. THIS IS TO FORM LATER ON FRIDAY/EARLY
SATURDAY MORNING...WITH AXIS ACROSS HISPANIOLA TO THE CENTRAL
CARIBBEAN/COSTA RICA-SOUTHERN NICARAGUA. WINDS OF 20-25KT ARE TO
ACCOMPANY THIS FEATURE AS IT PULLS ACROSS THE BASIN. LATER ON
SATURDAY IT MOVES ACROSS PUERTO RICO-VIRGIN ISLES WHILE TRAILING
TO THE CENTRAL CARIBBEAN. AS THE FRONT MOVES OVER THE BAHAMAS IT
IS TO FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM.
ACROSS NORTHERN HISPANIOLA...THE SHEAR LINE IS TO SUSTAIN RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM DURING THE DAY ON
FRIDAY TO EARLY SATURDAY...WHILE ACROSS PUERTO RICO EXPECTING
ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15MM. AS IT TRAILS TO
COSTA RICA/SOUTHERN NICARAGUA IT IS TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY...WITH MAXIMA OF 15-20MM LATER ON SATURDAY AS IT MOVES
TOWARDS WESTERN PANAMA.

BUILDING LOW LEVEL RIDGE ACROSS THE GULF-CARIBBEAN IS TO
STRENGTHEN THE TRADE WIND EASTERLIES ACROSS THE CENTRAL/WESTERN
CARIBBEAN AND OVER CENTRAL AMERICA. AT 850 HPA THE WINDS ACROSS
NICARAGUA ARE EXPECTED TO PEAK AT 30-35KT...WITH LOCALLY STRONGER
WINDS LIKELY OVER WESTERN NICARAGUA. THESE WINDS ARE TO CONVERGE
ON THE CARIBBEAN PLAINS OF COSTA RICA-BOCAS DEL TORO IN WESTERN
PANAMA AND SOUTHERN NICARAGUA...TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-25MM. OVER COLOMBIA...COLD WATER
UPWELLING ALONG THE WEST COAST HAS RESULTED IN A PWAT MINIMA AND
WELL BELOW NORMAL RAINFALL AMOUNTS. STRONG WINDS ARE LIKELY TO
PERSIST OVER THE NEXT FEW DAYS...WITH MOSTLY FAVORABLE WEATHER
CONDITIONS EXPECTED TO PREVAIL THROUGH SATURDAY MORNING.
HOWEVER...MOISTURE STARTS TO SURGE DURING THE DAY...WITH DIURNAL
CONVECTION ALONG THE ANDES AND COASTAL PLAINS TO RESULT IN
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM. MOST ACTIVE
CONVECTION IS EXPECTED TO THE SOUTH ALONG THE BORDER WITH
ECUADOR....WHERE ITCZ CONVERGENCE IS TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM. INLAND OVER AMAZONIA IN
COLOMBIA...A SURGE IN ACTIVITY IS EXPECTED ON FRIDAY-SUNDAY
MORNING...WITH DAILY RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
30-60MM.

OVER THE GUIANAS...MEANWHILE...A SOUTHERN HEMISPHERE TUTT LOW NEAR
10S 41W EXTENDS A TROUGH TO THE NORTHWEST ACROSS THE GUIANAS. THIS
TROUGH IS TO SLOWLY WEAKEN THROUGH SATURDAY EVENING.
MEANWHILE...IT IS TO ENHANCE CONVECTIVE DEVELOPMENT ACROSS THE
GUIANAS. OVER SURINAME TO FRENCH GUIANA EXPECTING RAINFALL AMOUNTS
OF 10-15MM/DAY AND MAXIMA OF 20-35MM. THIS IS EXPECTED TO DECREASE
TO 05-10MM/DAY AND MAXIMA OF 15MM LATER IN THE CYCLE. ACROSS
GUYANA EXPECTING ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF
15-20MM. THROUGH SATURDAY EVENING THIS DECREASES TO 05-10MM/DAY
AND MAXIMA OF 15MM.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL  24     36     48     60     72     84     96     TYPE
NONE

JN BAPTISTE...MS (SAINT LUCIA)
NANDA...MDS (SURINAME)
DAVISON...WPC (USA)
$$







000
FXCA20 KWBC 291905
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
205 PM EST THU JAN 29 2015

DISCUSSION FROM JANUARY 29/00UTC: DEEP MID LEVEL TROUGH ON THE
SOUTHERN STREAM EXTENDS ACROSS THE BAJA PENINSULA TO THE TROPICAL
PACIFIC. THIS TROUGH IS TO PRESS AGAINST A RIDGE TO THE EAST...AND
IN THIS PROCESS IT IS TO THEN SHEAR SHORT WAVE ENERGY ACROSS BAJA
PENINSULA-SONORA/CHIHUAHUA IN NORTHWEST MEXICO. THE HIGH AMPLITUDE
TROUGH IS TO INTERACT WITH THE ITCZ TO THE SOUTH...DRAWING DEEP
MOISTURE ACROSS THE BAJA PENINSULA/NORTHWEST STATES OF MEXICO.
STRONG CYCLONIC VORTICITY ADVECTION WILL COMBINE WITH THE HIGH
TERRAIN OF THE SIERRA MADRE TO RESULT IN AREAS OF ORGANIZED HEAVY
CONVECTION. ACROSS NORTHWEST MEXICO EXPECTING RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-30MM THROUGH FRIDAY MORNING...AND
15-20MM/DAY AND MAXIMA OF 25-50MM ON FRIDAY TO SATURDAY. EARLY ON
SATURDAY FOCUS OF THE CONVECTION SHIFTS TO SONORA MEXICO...WHERE
WE ALSO EXPECT RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
25-50MM. OTHER CONVECTION IS TO THEN BUILD EAST ACROSS THE
NORTH-CENTRAL TO NORTHEASTERN STATES OF MEXICO...WITH ACCUMULATION
OF 00-05MM/DAY AND MAXIMA OF 10MM.

MID/UPPER LEVEL RIDGE PATTERN IS TO INITIALLY CONFINE TO
MEXICO-NORTHERN CENTRAL AMERICA...WHILE ANCHORING ON A CLOSED HIGH
OVER COLIMA/NAYARIT TO THE SOUTHWEST OF MEXICO. THROUGH SATURDAY
MORNING THE RIDGE RELOCATES TO THE CENTRAL CARIBBEAN AS IT YIELDS
TO THE DEEP SOUTHERN STREAM TROUGH. THIS IS TO THEN BECOME THE
DOMINANT FEATURE ACROSS THE CARIBBEAN BASIN LATER DURING THE
WEEKEND. AS THE RIDGE MOVES TO THE EAST...CAP INVERSION OVER
MEXICO IS TO WEAKEN. HOWEVER...OPPOSITE IS TRUE ACROSS THE
CARIBBEAN BASIN...WITH RIDGE TO STRENGTHEN CAP INVERSION AS THE
CYCLE PROGRESSES.

DOWNSTREAM FROM THE MID LEVEL RIDGE...OVER THE WESTERN
ATLANTIC...A BROAD POLAR TROUGH EXTENDS SOUTH TO THE NORTHERN
CARIBBEAN ISLES. THE TROUGH IS LIFTING AS IT MEANDERS TO THE
EAST-NORTHEAST...AND EARLY ON FRIDAY IT IS FORECAST TO PULL.
ASSOCIATED FRONT...MEANWHILE...IS TO EXTEND ACROSS NORTHERN
HISPANIOLA TO THE NORTHWEST CARIBBEAN. THROUGH FRIDAY MORNING IT
MEANDERS NORTH TO THE SOUTHEAST BAHAMAS/TURKS-CUBA...AND THROUGH
SATURDAY MORNING IT IS EXPECTED TO FRONTOLIZE. MEANWHILE...THIS IS
TO ENHANCE MOISTURE CONVERGENCE ACROSS NORTHERN HISPANIOLA TO
FAVOR RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-35MM.
ACROSS THE SOUTHEAST BAHAMAS/EASTERN CUBA IT IS TO THEN FAVOR
RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM.

ANOTHER TROUGH IS TO CLEAR THE EASTERN SEABOARD OF THE USA BY
MIDAFTERNOON ON FRIDAY...TO MEANDER EAST ACROSS 60W LATER ON
SATURDAY. AS RIDGE BUILDS TO THE SOUTH ACROSS THE BASIN...THE
TROUGH IS FORECAST TO BOTTOM OUT FAR TO THE NORTH. ASSOCIATED
FRONT MOVES TO THE WESTERN ATLANTIC EARLY ON FRIDAY...AND LATER IN
THE DAY IT IS TO EXTEND ACROSS CENTRAL FLORIDA TO THE NORTHERN
GULF OF MEXICO. EARLY ON SATURDAY MORNING IT IS TO ENTER THE
NORTHWEST BAHAMAS...AND DURING THE EVENING HOURS THE FRONT MOVES
TO THE CENTRAL BAHAMAS-STRAITS OF FLORIDA TO THE NORTHERN
GULF/SOUTHERN USA. BUT LACKING UPPER LEVEL SUPPORT...EARLY ON
SUNDAY MORNING THE FRONT IS TO STALL ALONG 21N/22N. BUILDING POLAR
RIDGE ACROSS THE GULF OF MEXICO IS TO THEN TRIGGER A PREFRONTAL
SHEAR LINE ACROSS THE BASIN. THIS IS TO FORM LATER ON FRIDAY/EARLY
SATURDAY MORNING...WITH AXIS ACROSS HISPANIOLA TO THE CENTRAL
CARIBBEAN/COSTA RICA-SOUTHERN NICARAGUA. WINDS OF 20-25KT ARE TO
ACCOMPANY THIS FEATURE AS IT PULLS ACROSS THE BASIN. LATER ON
SATURDAY IT MOVES ACROSS PUERTO RICO-VIRGIN ISLES WHILE TRAILING
TO THE CENTRAL CARIBBEAN. AS THE FRONT MOVES OVER THE BAHAMAS IT
IS TO FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM.
ACROSS NORTHERN HISPANIOLA...THE SHEAR LINE IS TO SUSTAIN RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM DURING THE DAY ON
FRIDAY TO EARLY SATURDAY...WHILE ACROSS PUERTO RICO EXPECTING
ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15MM. AS IT TRAILS TO
COSTA RICA/SOUTHERN NICARAGUA IT IS TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY...WITH MAXIMA OF 15-20MM LATER ON SATURDAY AS IT MOVES
TOWARDS WESTERN PANAMA.

BUILDING LOW LEVEL RIDGE ACROSS THE GULF-CARIBBEAN IS TO
STRENGTHEN THE TRADE WIND EASTERLIES ACROSS THE CENTRAL/WESTERN
CARIBBEAN AND OVER CENTRAL AMERICA. AT 850 HPA THE WINDS ACROSS
NICARAGUA ARE EXPECTED TO PEAK AT 30-35KT...WITH LOCALLY STRONGER
WINDS LIKELY OVER WESTERN NICARAGUA. THESE WINDS ARE TO CONVERGE
ON THE CARIBBEAN PLAINS OF COSTA RICA-BOCAS DEL TORO IN WESTERN
PANAMA AND SOUTHERN NICARAGUA...TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-25MM. OVER COLOMBIA...COLD WATER
UPWELLING ALONG THE WEST COAST HAS RESULTED IN A PWAT MINIMA AND
WELL BELOW NORMAL RAINFALL AMOUNTS. STRONG WINDS ARE LIKELY TO
PERSIST OVER THE NEXT FEW DAYS...WITH MOSTLY FAVORABLE WEATHER
CONDITIONS EXPECTED TO PREVAIL THROUGH SATURDAY MORNING.
HOWEVER...MOISTURE STARTS TO SURGE DURING THE DAY...WITH DIURNAL
CONVECTION ALONG THE ANDES AND COASTAL PLAINS TO RESULT IN
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM. MOST ACTIVE
CONVECTION IS EXPECTED TO THE SOUTH ALONG THE BORDER WITH
ECUADOR....WHERE ITCZ CONVERGENCE IS TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM. INLAND OVER AMAZONIA IN
COLOMBIA...A SURGE IN ACTIVITY IS EXPECTED ON FRIDAY-SUNDAY
MORNING...WITH DAILY RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
30-60MM.

OVER THE GUIANAS...MEANWHILE...A SOUTHERN HEMISPHERE TUTT LOW NEAR
10S 41W EXTENDS A TROUGH TO THE NORTHWEST ACROSS THE GUIANAS. THIS
TROUGH IS TO SLOWLY WEAKEN THROUGH SATURDAY EVENING.
MEANWHILE...IT IS TO ENHANCE CONVECTIVE DEVELOPMENT ACROSS THE
GUIANAS. OVER SURINAME TO FRENCH GUIANA EXPECTING RAINFALL AMOUNTS
OF 10-15MM/DAY AND MAXIMA OF 20-35MM. THIS IS EXPECTED TO DECREASE
TO 05-10MM/DAY AND MAXIMA OF 15MM LATER IN THE CYCLE. ACROSS
GUYANA EXPECTING ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF
15-20MM. THROUGH SATURDAY EVENING THIS DECREASES TO 05-10MM/DAY
AND MAXIMA OF 15MM.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL  24     36     48     60     72     84     96     TYPE
NONE

JN BAPTISTE...MS (SAINT LUCIA)
NANDA...MDS (SURINAME)
DAVISON...WPC (USA)
$$






000
FXSA20 KWBC 291706
PMDSA

SOUTH AMERICA FORECAST DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1205 PM EST THU JAN 29 2015

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

MODEL DISCUSSION (VALID FROM JANUARY 29 AT 00UTC): THE 00 UTC GFS
OVERCORRECTED ACROSS THE WESTERN SOUTH ATLANTIC ON DAYS 04-06...
DEVELOPING A DEEPER/STRONGER TROUGH THAN WHAT THE OTHER MODELS
SUGGEST. MEAN OF THE GLOBAL ENSEMBLES FAVOR A WEAKER PERTURBATION
TO DEVELOP...A SOLUTION THE 06 GFS SUPPORTS. ALTHOUGH UNCERTAINTY
IS HIGH...OUR FORECAST CHARTS ARE HEAVILY BIASED TOWARDS THE
LATTER RUN OF THE MODEL.

BROAD MID/UPPER LEVEL TROUGH DOMINATES FLOW ACROSS THE WESTERN
SOUTH ATLANTIC EARLY IN THE CYCLE. THE TROUGH IS TO GRADUALLY PULL
TO THE EAST-SOUTHEAST AS THE CYCLE PROGRESSES...DAMPENING LATER IN
THE CYCLE AS SHORT WAVE ENERGY RAPIDLY SHEARS TO THE
EAST-SOUTHEAST. AT LOW LEVELS...BROAD RIDGE IS TO DOMINATE MOST OF
ARGENTINA/WESTERN ATLANTIC...WITH POLAR HIGH TO CENTER TO THE
EAST-SOUTHEAST OF THE BUENOS AIRES PROVINCE. AN ELONGATED FRONT
FLANKS THIS RIDGE...WITH AXIS TO THE NORTHWEST ACROSS SAO PAULO IN
BRASIL TO CORRIENTES IN ARGENTINA. THROUGH 36-48 HRS THE FRONT
LOSES UPPER LEVEL SUPPORT...WEAKENING TO A TROUGH OVER THE
SOUTHERN STATES OF BRASIL. EARLY IN THE CYCLE THIS IS TO FAVOR
ORGANIZED CONVECTION ACROSS SOUTHERN STATES OF BRASIL AND PORTIONS
OF SAO PAULO...WITH RAINFALL MAXIMA OF 30-60MM. THROUGH 48-60 HRS
THIS DECREASES TO 20-35MM...AND BY 96-108 HRS IT IS EXPECTED TO
PEAK AT 10-15MM.

PROGRESSIVE MID/UPPER LEVEL TROUGH IS TO FOLLOW...TO ENTER THE
EASTERN PACIFIC EARLY IN THE CYCLE. THIS IS TO THEN PRESS AGAINST
A RIDGE TO THE EAST...AS THE LATTER EXTENDS FROM NORTH-TO-SOUTH
ACROSS THE WESTERN ATLANTIC TO THE WEDDELL SEA. UNDER PRESSURE
FROM THE TROUGH TO THE WEST...THE RIDGE RELOCATES ALONG 30W/40W
LATER ON DAY 03...ALLOWING THE TROUGH TO MOVE INLAND ACROSS CHILE
TO ARGENTINA. THE TROUGH IS TO THEN PULL TO THE EAST-SOUTHEAST
WHILE GRADUALLY SHEARING SHORT WAVE ENERGY. AT LOW LEVELS...THIS
IS TO SUSTAIN A BROAD TROUGH ACROSS THE SOUTHEAST PACIFIC EARLY IN
THE CYCLE. SUCCESSIVE FRONTS ARE TO REVOLVE AROUND THIS AXIS...TO
THEN STREAM ACROSS TIERRA DEL FUEGO/EXTREME SOUTHERN PORTIONS OF
CHILE. THIS PATTERN IS TO PERSIST THROUGH 42-54 HRS...MEANWHILE
FAVORING LIGHT CONVECTION ACROSS TIERRA DEL FUEGO WHERE THE MAXIMA
IS TO PEAK AT 05-10MM ON DAY 02. BY 72-84 HRS THE FRONT IS TO
FINALLY MOVE NORTH ACROSS PATAGONIA IN ARGENTINA TO LA
PAMPA...WHERE IT IS TO STALL THROUGH 96-108 HRS. AS IT MOVES NORTH
ACROSS NORTHERN PATAGONIA TO LA PAMPA/BUENOS AIRES PROVINCE THIS
IS TO THEN TRIGGER SCATTERED CONVECTION WITH ACCUMULATION OF
10-15MM.

AT 200 HPA...BROAD CELL OF THE SUBTROPICAL RIDGE DOMINATES
NORTHERN CHILE/ARGENTINA-BOLIVIA-PERU AND SOUTHWEST BRASIL...WHILE
CENTERING ON A CLOSED HIGH OVER SOUTHERN BOLIVIA/NORTHERN CHILE.
RIDGE PATTERN IS FORECAST TO STRENGTHEN THROUGH 96-120 HRS...WITH
AXIS EXPECTED TO BUILD EAST ACROSS BRASIL. A TUTT TO THE
EAST...MEANWHILE...IS TO ORIGINATE ON A CLOSED LOW NEAR 12S
40W...WITH A TROUGH EXTENDING TO THE NORTHWEST ACROSS NORTHEAST
BRASIL TO THE GUIANAS. TUTT LOW IS TO RETROGRESS TO NORTHEAST
BRASIL THROUGH 48-60 HRS...BUT LATER IN THE CYCLE IT IS TO FILL TO
AN OPEN TROUGH AS THE RIDGE TO THE SOUTH STRENGTHENS/BUILDS.
BETWEEN THE RIDGE TO THE WEST AND THE TUTT TO THE EAST...AN UPPER
CONVERGENT PATTERN IS TO DOMINATE THE EASTERN STATES OF BRASIL
DURING THE NEXT 48-60 HRS. BUT AS THE TROUGH BEGINS TO
WEAKEN...AND THE RIDGE BUILDS...CONVECTION ACROSS NORTHEAST BRASIL
IS TO INTENSIFY. THROUGH 72-96 HRS ACTIVITY INCREASES TO SUSTAIN
MAXIMA OF 15-25MM. FARTHER WEST...THE BUILDING RIDGE IS TO
INITIALLY FOCUS MOISTURE ACROSS NORTHERN BOLIVIA TO SOUTHERN
PERU...WHERE WE EXPECT MAXIMA OF 30-60MM. THROUGH 48-60 HRS FOCUS
OF THE ORGANIZED CONVECTION SHIFTS TO AMAZONAS/ACRE IN
BRASIL-JUNGLE OF PERU TO SOUTHERN COLOMBIA. THIS IS TO THEN
PERSIST THROUGH 72-84 HRS. LATER IN THE CYCLE MOST ACTIVE
CONVECTION IS EXPECTED ALONG THE NEAR EQUATORIAL TROUGH TO THE
NORTH...WITH MAXIMA OF 20-35MM...WHILE OVER CENTRAL/SOUTHERN
PERU-ACRE-PARA IN BRASIL THE MAXIMA PEAKS AT 15-25MM.

ARREAGA...INAMHI (ECUADOR)
DURAN...SENAHMI (PERU)
DAVISON...WPC (USA)

$$






000
FXSA20 KWBC 291706
PMDSA

SOUTH AMERICA FORECAST DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1205 PM EST THU JAN 29 2015

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

MODEL DISCUSSION (VALID FROM JANUARY 29 AT 00UTC): THE 00 UTC GFS
OVERCORRECTED ACROSS THE WESTERN SOUTH ATLANTIC ON DAYS 04-06...
DEVELOPING A DEEPER/STRONGER TROUGH THAN WHAT THE OTHER MODELS
SUGGEST. MEAN OF THE GLOBAL ENSEMBLES FAVOR A WEAKER PERTURBATION
TO DEVELOP...A SOLUTION THE 06 GFS SUPPORTS. ALTHOUGH UNCERTAINTY
IS HIGH...OUR FORECAST CHARTS ARE HEAVILY BIASED TOWARDS THE
LATTER RUN OF THE MODEL.

BROAD MID/UPPER LEVEL TROUGH DOMINATES FLOW ACROSS THE WESTERN
SOUTH ATLANTIC EARLY IN THE CYCLE. THE TROUGH IS TO GRADUALLY PULL
TO THE EAST-SOUTHEAST AS THE CYCLE PROGRESSES...DAMPENING LATER IN
THE CYCLE AS SHORT WAVE ENERGY RAPIDLY SHEARS TO THE
EAST-SOUTHEAST. AT LOW LEVELS...BROAD RIDGE IS TO DOMINATE MOST OF
ARGENTINA/WESTERN ATLANTIC...WITH POLAR HIGH TO CENTER TO THE
EAST-SOUTHEAST OF THE BUENOS AIRES PROVINCE. AN ELONGATED FRONT
FLANKS THIS RIDGE...WITH AXIS TO THE NORTHWEST ACROSS SAO PAULO IN
BRASIL TO CORRIENTES IN ARGENTINA. THROUGH 36-48 HRS THE FRONT
LOSES UPPER LEVEL SUPPORT...WEAKENING TO A TROUGH OVER THE
SOUTHERN STATES OF BRASIL. EARLY IN THE CYCLE THIS IS TO FAVOR
ORGANIZED CONVECTION ACROSS SOUTHERN STATES OF BRASIL AND PORTIONS
OF SAO PAULO...WITH RAINFALL MAXIMA OF 30-60MM. THROUGH 48-60 HRS
THIS DECREASES TO 20-35MM...AND BY 96-108 HRS IT IS EXPECTED TO
PEAK AT 10-15MM.

PROGRESSIVE MID/UPPER LEVEL TROUGH IS TO FOLLOW...TO ENTER THE
EASTERN PACIFIC EARLY IN THE CYCLE. THIS IS TO THEN PRESS AGAINST
A RIDGE TO THE EAST...AS THE LATTER EXTENDS FROM NORTH-TO-SOUTH
ACROSS THE WESTERN ATLANTIC TO THE WEDDELL SEA. UNDER PRESSURE
FROM THE TROUGH TO THE WEST...THE RIDGE RELOCATES ALONG 30W/40W
LATER ON DAY 03...ALLOWING THE TROUGH TO MOVE INLAND ACROSS CHILE
TO ARGENTINA. THE TROUGH IS TO THEN PULL TO THE EAST-SOUTHEAST
WHILE GRADUALLY SHEARING SHORT WAVE ENERGY. AT LOW LEVELS...THIS
IS TO SUSTAIN A BROAD TROUGH ACROSS THE SOUTHEAST PACIFIC EARLY IN
THE CYCLE. SUCCESSIVE FRONTS ARE TO REVOLVE AROUND THIS AXIS...TO
THEN STREAM ACROSS TIERRA DEL FUEGO/EXTREME SOUTHERN PORTIONS OF
CHILE. THIS PATTERN IS TO PERSIST THROUGH 42-54 HRS...MEANWHILE
FAVORING LIGHT CONVECTION ACROSS TIERRA DEL FUEGO WHERE THE MAXIMA
IS TO PEAK AT 05-10MM ON DAY 02. BY 72-84 HRS THE FRONT IS TO
FINALLY MOVE NORTH ACROSS PATAGONIA IN ARGENTINA TO LA
PAMPA...WHERE IT IS TO STALL THROUGH 96-108 HRS. AS IT MOVES NORTH
ACROSS NORTHERN PATAGONIA TO LA PAMPA/BUENOS AIRES PROVINCE THIS
IS TO THEN TRIGGER SCATTERED CONVECTION WITH ACCUMULATION OF
10-15MM.

AT 200 HPA...BROAD CELL OF THE SUBTROPICAL RIDGE DOMINATES
NORTHERN CHILE/ARGENTINA-BOLIVIA-PERU AND SOUTHWEST BRASIL...WHILE
CENTERING ON A CLOSED HIGH OVER SOUTHERN BOLIVIA/NORTHERN CHILE.
RIDGE PATTERN IS FORECAST TO STRENGTHEN THROUGH 96-120 HRS...WITH
AXIS EXPECTED TO BUILD EAST ACROSS BRASIL. A TUTT TO THE
EAST...MEANWHILE...IS TO ORIGINATE ON A CLOSED LOW NEAR 12S
40W...WITH A TROUGH EXTENDING TO THE NORTHWEST ACROSS NORTHEAST
BRASIL TO THE GUIANAS. TUTT LOW IS TO RETROGRESS TO NORTHEAST
BRASIL THROUGH 48-60 HRS...BUT LATER IN THE CYCLE IT IS TO FILL TO
AN OPEN TROUGH AS THE RIDGE TO THE SOUTH STRENGTHENS/BUILDS.
BETWEEN THE RIDGE TO THE WEST AND THE TUTT TO THE EAST...AN UPPER
CONVERGENT PATTERN IS TO DOMINATE THE EASTERN STATES OF BRASIL
DURING THE NEXT 48-60 HRS. BUT AS THE TROUGH BEGINS TO
WEAKEN...AND THE RIDGE BUILDS...CONVECTION ACROSS NORTHEAST BRASIL
IS TO INTENSIFY. THROUGH 72-96 HRS ACTIVITY INCREASES TO SUSTAIN
MAXIMA OF 15-25MM. FARTHER WEST...THE BUILDING RIDGE IS TO
INITIALLY FOCUS MOISTURE ACROSS NORTHERN BOLIVIA TO SOUTHERN
PERU...WHERE WE EXPECT MAXIMA OF 30-60MM. THROUGH 48-60 HRS FOCUS
OF THE ORGANIZED CONVECTION SHIFTS TO AMAZONAS/ACRE IN
BRASIL-JUNGLE OF PERU TO SOUTHERN COLOMBIA. THIS IS TO THEN
PERSIST THROUGH 72-84 HRS. LATER IN THE CYCLE MOST ACTIVE
CONVECTION IS EXPECTED ALONG THE NEAR EQUATORIAL TROUGH TO THE
NORTH...WITH MAXIMA OF 20-35MM...WHILE OVER CENTRAL/SOUTHERN
PERU-ACRE-PARA IN BRASIL THE MAXIMA PEAKS AT 15-25MM.

ARREAGA...INAMHI (ECUADOR)
DURAN...SENAHMI (PERU)
DAVISON...WPC (USA)

$$







000
FXUS02 KWBC 291558
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1057 AM EST THU JAN 29 2015

VALID 12Z SUN FEB 01 2015 - 12Z THU FEB 05 2015

...OVERVIEW...

RECENT MULTI-DAY MEANS FROM THE MODELS/ENSEMBLE MEANS HAVE BEEN
MORE AGREEABLE AND CONSISTENT THAN AVERAGE... SHOWING THAT THE
PATTERN SHOULD SETTLE INTO A WEST COAST RIDGE/CNTRL-ERN CONUS
TROUGH CONFIGURATION.  THIS PATTERN ALSO HAS GOOD TELECONNECTION
SUPPORT RELATIVE TO UPSTREAM FEATURES... A CORE OF NEG HGT
ANOMALIES NEAR 160W AND A CORE OF POS HGT ANOMALIES NEAR
KAMCHATKA.  FCSTS OF THESE ANOMALY CENTERS ARE ALSO REMARKABLY
SIMILAR IN THE D+8 MEANS.  WHILE CONFIDENCE IS ABOVE AVG IN THE
EVOLVING LARGE SCALE FLOW BY THE LATTER HALF OF THE PERIOD THERE
ARE STILL PERSISTENT UNCERTAINTIES WITH SIGNIFICANT FEATURES...
INCL THE SYSTEM AFFECTING THE ERN HALF OF THE CONUS SUN-MON AS
WELL AS TIMING OF A FRONT DROPPING SEWD FROM CANADA AND AN UPR LOW
FCST TO EJECT FROM NRN MEXICO.


...GUIDANCE/UNCERTAINTY EVALUATION AND PREFERENCES...

FOR DAYS 3-6 SUN-WED THE UPDATED WPC FCST INCORPORATES A BLEND OF
00Z ECMWF/00Z-06Z GFS RUNS AND 06Z GEFS/00Z ECMWF MEANS... A
LITTLE MORE TOWARD THE OPERATIONAL RUNS DAYS 3-5 AND ENSMEANS DAY
6.  THIS SOLN REFLECTS THE MOST COMMON ASPECTS OF LATEST GUIDANCE
WHILE DOWNPLAYING LOWER CONFIDENCE DETAILS OF ONE OR MORE
INDIVIDUAL SOLNS.  DAY 7 THU USES A BLEND OF HALF 00Z ECMWF MEAN
AND THE REMAINDER 06Z GEFS/00Z NAEFS MEAN AS CONFIDENCE IN MODEL
SPECIFICS FURTHER DECLINES.

CONFIDENCE REMAINS LOWER THAN DESIRED FOR THE ERN SYSTEM SUN-MON.
WOULD NOT BE SURPRISED TO SEE CONTINUED VARIABILITY IN THE
GUIDANCE AT LEAST UNTIL THE UPR SUPPORT... WEAK NERN PAC ENERGY
AND SHEARED ENERGY OVER ALASKA... FINALLY REACH WRN CANADA BY SAT.
 THE SMALL SCALE NATURE OF BOTH PIECES OF ENERGY IS LIKELY
CONTRIBUTING TO FCST DIFFICULTY.  OVER MULTIPLE DAYS
MODEL/ENSEMBLE GUIDANCE HAS WAFFLED CONSIDERABLY BTWN
WEAK/PROGRESSIVE AND STRONGER/SLOWER SFC SOLNS.  YDAYS 12Z MDLS
GENERALLY ADJUSTED MUCH WEAKER/FASTER THAN WHAT CONSTITUTED A
MAJORITY CLUSTER FROM THE PAST 1-2 DAYS... BUT 00Z/06Z SOLNS HAVE
BACKED UP A BIT TO WHAT SEEMS A REASONABLE INTERMEDIATE FCST
ESPECIALLY IN LIGHT OF 00Z CMC/UKMET RUNS HOLDING ONTO A
SLOWER/WWD SFC SYSTEM MORE SIMILAR TO SOME EARLIER GFS/ECMWF RUNS.
 THE FULL ENSEMBLE SPREAD FOR SFC LOWS IS STILL UNUSUALLY BROAD
GIVEN THE FCST TIME FRAME WITH THE ONLY IMPROVEMENT TODAY BEING A
TRIMMING OF THE NRN SIDE OF THE ENVELOPE.

UPSTREAM FROM THIS SYSTEM... RECENT TRENDS HAVE BEEN TOWARD A
WEAKER DEPICTION OF ERN PAC ENERGY FLOWING THROUGH WEST COAST MEAN
RIDGE AROUND SUN-MON.  THESE TRENDS AND RELATIVE WEAKNESS OF THE
ENERGY IN GENERAL SEEM TO FAVOR DOWNPLAYING THE 00Z CMC AND
ESPECIALLY 00Z ECMWF THAT BRING A WELL DEFINED SFC WAVE INTO THE
NRN PAC NW.  THE FAVORED STARTING BLEND HAS SUFFICIENTLY LOW 00Z
ECMWF WEIGHTING TO MINIMIZE THE DEFINITION OF SUCH A FEATURE.
MEANWHILE SOMEWHAT BETTER MAINTENANCE OF THE RIDGE IS CONSISTENT
WITH SLIGHTLY FASTER TRENDS FOR THE COLD FRONT DENOTING THE
LEADING EDGE OF COLDER AIR DROPPING INTO THE NRN PLAINS BY EARLY
TUE AND CONTINUING SEWD THEREAFTER.

THE FCST ALONG THE SRN TIER AND EAST COAST DURING THE LATTER HALF
OF THE PERIOD IS STILL UNCERTAIN WITH SIGNIFICANT DIFFS PERSISTING
FOR THE UPR LOW EJECTING FROM MEXICO.  THERE IS A STRONG ENOUGH
SIGNAL TO INDICATE SOME WAVINESS FROM THE GULF COAST INTO THE WRN
ATLC BUT WITH SOMEWHAT LESS IMPACT THAN RECENT ECMWF RUNS.  ON THE
OTHER HAND GFS/GEFS MEAN RUNS MAY BECOME A LITTLE FAST WITH THE
CONUS TROUGH LATE IN THE PERIOD AND PUSH THE PCPN THREAT TOO FAR
OFFSHORE.  THE PREFERRED BLEND OFFERS A BALANCE BTWN THESE TWO
EXTREMES.

ONE LAST NOTE IS THAT THE 00Z GFS ON DAY 6 WED AND 00Z ECMWF ON
DAY 7 THU MAY BE OVERDONE WITH THE AMOUNT OF ERN PAC ENERGY THAT
PUSHES INTO THE WEST COAST RIDGE... FAVORING EXCLUSION OF THOSE
SOLNS AT THE TIMES INDICATED.


...SENSIBLE WEATHER HIGHLIGHTS...

FOR THE SUN-MON SYSTEM OVER THE EAST... BASED ON MAJORITY GUIDANCE
SOLNS OF THE PAST 12-24 HRS EXPECT BEST POTENTIAL FOR SIGNIFICANT
WINTER WEATHER FROM THE MID MS VLY/OH VLY THROUGH THE NRN HALF OF
THE MID ATLC/EXTREME SRN NEW ENGLAND.  CURRENT FLATTER DEPICTION
OF THIS SYSTEM RELATIVE TO SOME EARLIER SOLNS SUGGESTS PCPN WOULD
BE MOSTLY RAIN S/SNOW N WITH THE TRANSITION BEING A BAND OF SNOW
WITH ABOVE FREEZING SFC TEMPS.  CONFIDENCE FOR THIS SYSTEM IS
BELOW AVG SO FURTHER CHANGES FROM THIS MOST LIKELY SCENARIO ARE
QUITE PSBL.  BEHIND THIS SYSTEM EXPECT A PERIOD OF SNOW TO THE LEE
OF GREAT LAKES WITHOUT ICE COVER.  WRN CONUS PCPN WILL BE CONFINED
TO NRN AREAS WITH GENERALLY BRIEF/LOCALIZED ENHANCED TOTALS OVER
FAVORED TERRAIN.  FROM MON ONWARD SOME OF THIS MSTR MAY BE CARRIED
ACROSS THE PLAINS/NORTHEAST BY A WAVE/FRONT AT THE LEADING EDGE OF
COLD AIR PUSHING SEWD FROM CANADA.  MEANWHILE SOME RNFL IS PSBL
FROM MON NIGHT ONWARD ACROSS THE SOUTH/SOUTHEAST IN ASSOC WITH THE
UPR LOW EJECTING FROM MEXICO BUT WITH LOW CONFIDENCE FOR
TIMING/COVERAGE/INTENSITY OF RNFL.  TIMING OF COLDER AIR ARRIVING
FROM THE NW WILL HAVE TO BE WATCHED FOR WINTER WEATHER POTENTIAL
IN THE NWRN PERIPHERY OF THIS PCPN SHIELD BUT CURRENT
PROBABILITIES ARE FAIRLY LOW.  THE MEAN PATTERN WILL FAVOR ABOVE
NORMAL TEMPS OVER THE WEST... VARIABLE READINGS OVER THE PLAINS...
AND BELOW NORMAL TEMPS OVER THE EAST.  GREATEST WARM ANOMALIES
SHOULD BE IN THE PLUS 10-15F RANGE OVER/NEAR THE GRTBASIN WHILE
MINUS 15-25F OR SO ANOMALIES MAY EXTEND FROM FROM THE GRTLKS/OH
VLY/TN VLY NEWD INTO NEW ENGLAND MON-TUE.

RAUSCH

$$







000
FXUS02 KWBC 291558
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1057 AM EST THU JAN 29 2015

VALID 12Z SUN FEB 01 2015 - 12Z THU FEB 05 2015

...OVERVIEW...

RECENT MULTI-DAY MEANS FROM THE MODELS/ENSEMBLE MEANS HAVE BEEN
MORE AGREEABLE AND CONSISTENT THAN AVERAGE... SHOWING THAT THE
PATTERN SHOULD SETTLE INTO A WEST COAST RIDGE/CNTRL-ERN CONUS
TROUGH CONFIGURATION.  THIS PATTERN ALSO HAS GOOD TELECONNECTION
SUPPORT RELATIVE TO UPSTREAM FEATURES... A CORE OF NEG HGT
ANOMALIES NEAR 160W AND A CORE OF POS HGT ANOMALIES NEAR
KAMCHATKA.  FCSTS OF THESE ANOMALY CENTERS ARE ALSO REMARKABLY
SIMILAR IN THE D+8 MEANS.  WHILE CONFIDENCE IS ABOVE AVG IN THE
EVOLVING LARGE SCALE FLOW BY THE LATTER HALF OF THE PERIOD THERE
ARE STILL PERSISTENT UNCERTAINTIES WITH SIGNIFICANT FEATURES...
INCL THE SYSTEM AFFECTING THE ERN HALF OF THE CONUS SUN-MON AS
WELL AS TIMING OF A FRONT DROPPING SEWD FROM CANADA AND AN UPR LOW
FCST TO EJECT FROM NRN MEXICO.


...GUIDANCE/UNCERTAINTY EVALUATION AND PREFERENCES...

FOR DAYS 3-6 SUN-WED THE UPDATED WPC FCST INCORPORATES A BLEND OF
00Z ECMWF/00Z-06Z GFS RUNS AND 06Z GEFS/00Z ECMWF MEANS... A
LITTLE MORE TOWARD THE OPERATIONAL RUNS DAYS 3-5 AND ENSMEANS DAY
6.  THIS SOLN REFLECTS THE MOST COMMON ASPECTS OF LATEST GUIDANCE
WHILE DOWNPLAYING LOWER CONFIDENCE DETAILS OF ONE OR MORE
INDIVIDUAL SOLNS.  DAY 7 THU USES A BLEND OF HALF 00Z ECMWF MEAN
AND THE REMAINDER 06Z GEFS/00Z NAEFS MEAN AS CONFIDENCE IN MODEL
SPECIFICS FURTHER DECLINES.

CONFIDENCE REMAINS LOWER THAN DESIRED FOR THE ERN SYSTEM SUN-MON.
WOULD NOT BE SURPRISED TO SEE CONTINUED VARIABILITY IN THE
GUIDANCE AT LEAST UNTIL THE UPR SUPPORT... WEAK NERN PAC ENERGY
AND SHEARED ENERGY OVER ALASKA... FINALLY REACH WRN CANADA BY SAT.
 THE SMALL SCALE NATURE OF BOTH PIECES OF ENERGY IS LIKELY
CONTRIBUTING TO FCST DIFFICULTY.  OVER MULTIPLE DAYS
MODEL/ENSEMBLE GUIDANCE HAS WAFFLED CONSIDERABLY BTWN
WEAK/PROGRESSIVE AND STRONGER/SLOWER SFC SOLNS.  YDAYS 12Z MDLS
GENERALLY ADJUSTED MUCH WEAKER/FASTER THAN WHAT CONSTITUTED A
MAJORITY CLUSTER FROM THE PAST 1-2 DAYS... BUT 00Z/06Z SOLNS HAVE
BACKED UP A BIT TO WHAT SEEMS A REASONABLE INTERMEDIATE FCST
ESPECIALLY IN LIGHT OF 00Z CMC/UKMET RUNS HOLDING ONTO A
SLOWER/WWD SFC SYSTEM MORE SIMILAR TO SOME EARLIER GFS/ECMWF RUNS.
 THE FULL ENSEMBLE SPREAD FOR SFC LOWS IS STILL UNUSUALLY BROAD
GIVEN THE FCST TIME FRAME WITH THE ONLY IMPROVEMENT TODAY BEING A
TRIMMING OF THE NRN SIDE OF THE ENVELOPE.

UPSTREAM FROM THIS SYSTEM... RECENT TRENDS HAVE BEEN TOWARD A
WEAKER DEPICTION OF ERN PAC ENERGY FLOWING THROUGH WEST COAST MEAN
RIDGE AROUND SUN-MON.  THESE TRENDS AND RELATIVE WEAKNESS OF THE
ENERGY IN GENERAL SEEM TO FAVOR DOWNPLAYING THE 00Z CMC AND
ESPECIALLY 00Z ECMWF THAT BRING A WELL DEFINED SFC WAVE INTO THE
NRN PAC NW.  THE FAVORED STARTING BLEND HAS SUFFICIENTLY LOW 00Z
ECMWF WEIGHTING TO MINIMIZE THE DEFINITION OF SUCH A FEATURE.
MEANWHILE SOMEWHAT BETTER MAINTENANCE OF THE RIDGE IS CONSISTENT
WITH SLIGHTLY FASTER TRENDS FOR THE COLD FRONT DENOTING THE
LEADING EDGE OF COLDER AIR DROPPING INTO THE NRN PLAINS BY EARLY
TUE AND CONTINUING SEWD THEREAFTER.

THE FCST ALONG THE SRN TIER AND EAST COAST DURING THE LATTER HALF
OF THE PERIOD IS STILL UNCERTAIN WITH SIGNIFICANT DIFFS PERSISTING
FOR THE UPR LOW EJECTING FROM MEXICO.  THERE IS A STRONG ENOUGH
SIGNAL TO INDICATE SOME WAVINESS FROM THE GULF COAST INTO THE WRN
ATLC BUT WITH SOMEWHAT LESS IMPACT THAN RECENT ECMWF RUNS.  ON THE
OTHER HAND GFS/GEFS MEAN RUNS MAY BECOME A LITTLE FAST WITH THE
CONUS TROUGH LATE IN THE PERIOD AND PUSH THE PCPN THREAT TOO FAR
OFFSHORE.  THE PREFERRED BLEND OFFERS A BALANCE BTWN THESE TWO
EXTREMES.

ONE LAST NOTE IS THAT THE 00Z GFS ON DAY 6 WED AND 00Z ECMWF ON
DAY 7 THU MAY BE OVERDONE WITH THE AMOUNT OF ERN PAC ENERGY THAT
PUSHES INTO THE WEST COAST RIDGE... FAVORING EXCLUSION OF THOSE
SOLNS AT THE TIMES INDICATED.


...SENSIBLE WEATHER HIGHLIGHTS...

FOR THE SUN-MON SYSTEM OVER THE EAST... BASED ON MAJORITY GUIDANCE
SOLNS OF THE PAST 12-24 HRS EXPECT BEST POTENTIAL FOR SIGNIFICANT
WINTER WEATHER FROM THE MID MS VLY/OH VLY THROUGH THE NRN HALF OF
THE MID ATLC/EXTREME SRN NEW ENGLAND.  CURRENT FLATTER DEPICTION
OF THIS SYSTEM RELATIVE TO SOME EARLIER SOLNS SUGGESTS PCPN WOULD
BE MOSTLY RAIN S/SNOW N WITH THE TRANSITION BEING A BAND OF SNOW
WITH ABOVE FREEZING SFC TEMPS.  CONFIDENCE FOR THIS SYSTEM IS
BELOW AVG SO FURTHER CHANGES FROM THIS MOST LIKELY SCENARIO ARE
QUITE PSBL.  BEHIND THIS SYSTEM EXPECT A PERIOD OF SNOW TO THE LEE
OF GREAT LAKES WITHOUT ICE COVER.  WRN CONUS PCPN WILL BE CONFINED
TO NRN AREAS WITH GENERALLY BRIEF/LOCALIZED ENHANCED TOTALS OVER
FAVORED TERRAIN.  FROM MON ONWARD SOME OF THIS MSTR MAY BE CARRIED
ACROSS THE PLAINS/NORTHEAST BY A WAVE/FRONT AT THE LEADING EDGE OF
COLD AIR PUSHING SEWD FROM CANADA.  MEANWHILE SOME RNFL IS PSBL
FROM MON NIGHT ONWARD ACROSS THE SOUTH/SOUTHEAST IN ASSOC WITH THE
UPR LOW EJECTING FROM MEXICO BUT WITH LOW CONFIDENCE FOR
TIMING/COVERAGE/INTENSITY OF RNFL.  TIMING OF COLDER AIR ARRIVING
FROM THE NW WILL HAVE TO BE WATCHED FOR WINTER WEATHER POTENTIAL
IN THE NWRN PERIPHERY OF THIS PCPN SHIELD BUT CURRENT
PROBABILITIES ARE FAIRLY LOW.  THE MEAN PATTERN WILL FAVOR ABOVE
NORMAL TEMPS OVER THE WEST... VARIABLE READINGS OVER THE PLAINS...
AND BELOW NORMAL TEMPS OVER THE EAST.  GREATEST WARM ANOMALIES
SHOULD BE IN THE PLUS 10-15F RANGE OVER/NEAR THE GRTBASIN WHILE
MINUS 15-25F OR SO ANOMALIES MAY EXTEND FROM FROM THE GRTLKS/OH
VLY/TN VLY NEWD INTO NEW ENGLAND MON-TUE.

RAUSCH

$$






000
FXSA20 KWBC 291358
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
857 AM EST THU JAN 29 2015

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

SYNOPSIS (VALID FROM JANUARY 29 AT 00UTC): AT 200 HPA...THE
SUBTROPICAL RIDGE CONTINUES TO BUILD OVER NORTHWEST SOUTH AMERICA
WHILE ANCHORING ON A CLOSED HIGH OVER THE ALTIPLANO OF BOLIVIA.
THIS HIGH EXTENDS A RIDGE TO THE SOUTHEAST ACROSS MATO GROSSO-SAO
PAULO IN BRASIL TO THE SOUTH PACIFIC. A SHORT WAVE TROUGH TO THE
SOUTH...MEANWHILE...EXTENDS NORTH FROM CORRIENTES IN ARGENTINA TO
SOUTHEAST BOLIVIA. THIS...AND THE RIDGE ALOFT...PROVIDE
VENTILATION TO DEEP CONVECTION ACROSS PARAGUAY-BOLIVIA-SOUTHEAST
BRASIL. A RETROGRESSING TUTT LOW TO THE NORTH CENTERS NEAR 09S
35W...EXTENDING A TROUGH TO THE NORTHWEST ACROSS NORTHERN BRASIL
TO THE GUIANAS/COLOMBIA. THIS FAVORS AN UPPER CONVERGENT/SUBSIDENT
PATTERN ALOFT THAT IS INHIBITING DEEP CONVECTION ACROSS BRASIL TO
THE EAST OF 50W.

THE 250 HPA JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH A FINGER
BETWEEN 58S 91W AND 65S 60W. THE NORTHERN POLAR LIES ALONG A 140KT
MAXIMUM AT 51S 121W...45S 101W...55S 86W...61S 64W...LAS MALVINAS/
FALKLAND ISLANDS...EXITING AT 45S 59W. IT REFORMS AT 41S
56W...ALONG A 162KT MAXIMUM AT 46S 44W...47S 35W...A 167KT MAXIMUM
AT 43S 26W...AND 36S 13W. THE SUBTROPICAL JET HAS ITS ENTRANCE AT
41S 105W...ALONG 42S 96W...EXITING AT 46S 87W. IT HAS A FINGER TO
THE EAST THAT EXTENDS BETWEEN 48S 66W AND 38S 63W. THE JET REFORMS
AT 34S 61W...ALONG 40S 50W...43S 40W...39S 28W...EXITING AT 34S
21W.

AT 500 HPA...A BROAD TROUGH ENTERED THE EASTERN SOUTH
PACIFIC...ENVELOPING AREA BETWEEN 130W-80W AND TO THE SOUTH OF
30S...WHILE ANCHORING ON A CLOSED LOW AT 65S 100W. A
NORTH-TO-SOUTH RIDGE TO THE EAST EXTENDS FROM CENTRAL/SOUTHERN
CHILE TO THE ANTARCTIC PENINSULA. DOWNSTREAM FROM THIS AXIS...A
LOW NEAR 53S 49W EXTENDS A TROUGH TO THE NORTHWEST ACROSS RIO DE
LA PLATA/ENTRE RIOS IN ARGENTINA. THIS IS FOCUSING SHORT WAVE
ENERGY ACROSS URUGUAY/ENTRE RIOS IN ARGENTINA. A RIDGE TO THE
NORTH EXTENDS WEST ACROSS SOUTHEAST TO CENTRAL BRASIL.

AT LOW LEVELS...AN OCCLUDED 954 HPA LOW AT 68S 106W EXTENDS A
FRONT ALONG A 968 HPA LOW AT 71S 81W...64S 75W...A 974 HPA LOW AT
57S 87W...50S 97W...A 998 HPA LOW AT 40S 98W...AND 38S 109W. ON
THE NORTHERN STREAM...FARTHER TO THE EAST...AN OCCLUDED 986 HPA
LOW AT 51S 47W EXTENDS A FRONT ALONG A 994 HPA LOW AT 50S
39W...45S 37W...A 1006 HPA LOW AT 42S 40W...39S 41W...A 1006 HPA
LOW AT 36S 45W...A 1006 HPA LOW AT 33S 51W...SOUTHERN BRASIL TO
MENDOZA IN ARGENTINA. THIS SUSTAINS SCATTERED DEEP CONVECTION
ACROSS RN BRASIL TO NORTHERN PROVINCES IN ARGENTINA. A POLAR RIDGE
TO THE SOUTH CENTERS ON A 1017 HPA HIGH AT 42S 61W.


ARREAGA...INAMHI (ECUADOR)
DURAN...SENAHMI (PERU)
DAVISON...WPC (USA)
GALVEZ...WPC (USA)

$$






000
FXSA20 KWBC 291358
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
857 AM EST THU JAN 29 2015

GFS DATA AT FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/

SYNOPSIS (VALID FROM JANUARY 29 AT 00UTC): AT 200 HPA...THE
SUBTROPICAL RIDGE CONTINUES TO BUILD OVER NORTHWEST SOUTH AMERICA
WHILE ANCHORING ON A CLOSED HIGH OVER THE ALTIPLANO OF BOLIVIA.
THIS HIGH EXTENDS A RIDGE TO THE SOUTHEAST ACROSS MATO GROSSO-SAO
PAULO IN BRASIL TO THE SOUTH PACIFIC. A SHORT WAVE TROUGH TO THE
SOUTH...MEANWHILE...EXTENDS NORTH FROM CORRIENTES IN ARGENTINA TO
SOUTHEAST BOLIVIA. THIS...AND THE RIDGE ALOFT...PROVIDE
VENTILATION TO DEEP CONVECTION ACROSS PARAGUAY-BOLIVIA-SOUTHEAST
BRASIL. A RETROGRESSING TUTT LOW TO THE NORTH CENTERS NEAR 09S
35W...EXTENDING A TROUGH TO THE NORTHWEST ACROSS NORTHERN BRASIL
TO THE GUIANAS/COLOMBIA. THIS FAVORS AN UPPER CONVERGENT/SUBSIDENT
PATTERN ALOFT THAT IS INHIBITING DEEP CONVECTION ACROSS BRASIL TO
THE EAST OF 50W.

THE 250 HPA JET ANALYSIS SHOWS THE SOUTHERN POLAR WITH A FINGER
BETWEEN 58S 91W AND 65S 60W. THE NORTHERN POLAR LIES ALONG A 140KT
MAXIMUM AT 51S 121W...45S 101W...55S 86W...61S 64W...LAS MALVINAS/
FALKLAND ISLANDS...EXITING AT 45S 59W. IT REFORMS AT 41S
56W...ALONG A 162KT MAXIMUM AT 46S 44W...47S 35W...A 167KT MAXIMUM
AT 43S 26W...AND 36S 13W. THE SUBTROPICAL JET HAS ITS ENTRANCE AT
41S 105W...ALONG 42S 96W...EXITING AT 46S 87W. IT HAS A FINGER TO
THE EAST THAT EXTENDS BETWEEN 48S 66W AND 38S 63W. THE JET REFORMS
AT 34S 61W...ALONG 40S 50W...43S 40W...39S 28W...EXITING AT 34S
21W.

AT 500 HPA...A BROAD TROUGH ENTERED THE EASTERN SOUTH
PACIFIC...ENVELOPING AREA BETWEEN 130W-80W AND TO THE SOUTH OF
30S...WHILE ANCHORING ON A CLOSED LOW AT 65S 100W. A
NORTH-TO-SOUTH RIDGE TO THE EAST EXTENDS FROM CENTRAL/SOUTHERN
CHILE TO THE ANTARCTIC PENINSULA. DOWNSTREAM FROM THIS AXIS...A
LOW NEAR 53S 49W EXTENDS A TROUGH TO THE NORTHWEST ACROSS RIO DE
LA PLATA/ENTRE RIOS IN ARGENTINA. THIS IS FOCUSING SHORT WAVE
ENERGY ACROSS URUGUAY/ENTRE RIOS IN ARGENTINA. A RIDGE TO THE
NORTH EXTENDS WEST ACROSS SOUTHEAST TO CENTRAL BRASIL.

AT LOW LEVELS...AN OCCLUDED 954 HPA LOW AT 68S 106W EXTENDS A
FRONT ALONG A 968 HPA LOW AT 71S 81W...64S 75W...A 974 HPA LOW AT
57S 87W...50S 97W...A 998 HPA LOW AT 40S 98W...AND 38S 109W. ON
THE NORTHERN STREAM...FARTHER TO THE EAST...AN OCCLUDED 986 HPA
LOW AT 51S 47W EXTENDS A FRONT ALONG A 994 HPA LOW AT 50S
39W...45S 37W...A 1006 HPA LOW AT 42S 40W...39S 41W...A 1006 HPA
LOW AT 36S 45W...A 1006 HPA LOW AT 33S 51W...SOUTHERN BRASIL TO
MENDOZA IN ARGENTINA. THIS SUSTAINS SCATTERED DEEP CONVECTION
ACROSS RN BRASIL TO NORTHERN PROVINCES IN ARGENTINA. A POLAR RIDGE
TO THE SOUTH CENTERS ON A 1017 HPA HIGH AT 42S 61W.


ARREAGA...INAMHI (ECUADOR)
DURAN...SENAHMI (PERU)
DAVISON...WPC (USA)
GALVEZ...WPC (USA)

$$







000
FXCA20 KWBC 291153
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
652 AM EST THU JAN 29 2015

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI. BROAD POLAR
TROUGH ACROSS THE WESTERN NORTH ATLANTIC SUSTAINS A SURFACE FRONT
THAT TRAILS ACROSS NORTHERN HISPANIOLA TO THE NORTHWEST CARIBBEAN.
FURTHERMORE...UNDER INFLUENCE OF THE DEEP POLAR TROUGH PATTERN TO
THE NORTH...AN INDUCED/ INVERTED TROUGH NOW EXTENDS OVER THE
EASTERN CARIBBEAN ALONG 63W/64W. ALSO...A SHEAR LINE EXTENDS
ACROSS EASTERN HISPANIOLA TO THE SOUTHERN CARIBBEAN. MOST ACTIVE
CONVECTION IS DEVELOPING IN ASSOCIATION WITH THE SURFACE FRONT AS
IT MEANDERS ALONG THE NORTH COAST OF HISPANIOLA.

UPPER LEVEL TROUGH IS EXPECTED TO PULL AWAY THROUGH FRIDAY
MORNING. ON ITS WAKE...A RIDGE IS TO GRADUALLY ESTABLISH OVER
NORTHERN SOUTH AMERICA/CARIBBEAN TO THE GREATER ANTILLES-THE
BAHAMAS. AS THE RIDGE BUILDS...TRADE WINDS CAP IS TO GRADUALLY
STRENGTHEN THROUGH MIDDAY ON FRIDAY. THIS IS TO THEN HOLD THROUGH
THE WEEKEND/EARLY NEXT WEEK. BEST CHANCE FOR CONVECTION MIGHT BE
TODAY-EARLY FRIDAY MORNING AS THE BASE OF THE MID LEVEL TROUGH AND
A WEEK CYCLONIC MAXIMA GRAZE PUERTO RICO/NORTHERN VI. AT LOW
LEVELS...SURFACE FRONT IS EXPECTED TO STALL FAR TO THE NORTH...AND
GRADUALLY WEAKEN/FRONTOLIZE DURING THE WEEKEND. SHEAR LINE IS TO
MEANDER OVER THE FORECAST AREA DURING THE NEXT COUPLE OF DAYS. BUT
LACKING UPPER LEVEL SUPPORT IT IS NOT EXPECTED TO TRIGGER
SIGNIFICANT CONVECTION. PER THE HIGH RESOLUTION MODELS...IT LOOKS
LIKE MEASURABLE RAINFALL AMOUNTS ARE TO CONFINE TO THE
CENTRAL/WESTERN PORTIONS OF THE CORDILLERA OVER PUERTO RICO...WITH
LIGHT CONVECTION POSSIBLE ALONG THE NORTH COAST AS THE OCCASIONAL
TRADE WIND SHOWER STREAMS ACROSS THE FORECAST AREA.

ANOTHER FRONT IS TO CLEAR THE EASTERN SEABOARD OF THE USA EARLY ON
FRIDAY...BUT THIS IS TO STALL FAR TO THE NORTH. BUILDING POLAR
RIDGE TO THE WEST IS TO THEN SUSTAIN ANOTHER SHEAR LINE ACROSS THE
FORECAST AREA LATER ON SATURDAY...BUT THROUGH MIDDAY ON SUNDAY IT
IS TO CONTINUE FARTHER EAST AND SOUTH ACROSS THE FRENCH ISLES AS
BROAD RIDGE SETTLES TO THE NORTH. BRISK NORTHEASTERLY TRADES ARE
TO ACCOMPANY THIS FEATURE...WITH WINDY CONDITIONS LIKELY TO
PERSIST THROUGH MONDAY EVENING/EARLY TUESDAY MORNING. GLOBAL
MODELS GENERALLY AGREE ON POTENTIAL FOR SCATTERED SHOWERS TO
ACCOMPANY THIS FEATURE AS IT ENTERS PUERTO RICO LATER ON
SATURDAY...WITH BOTH EUROPEAN MODELS SHOWING A SOMEWHAT MORE
ACTIVE PATTERN THAN WHAT THE GFS SUGGESTS.

JN BAPTISTE...MS (SAINT LUCIA)
NANDA...MDS (SURINAME)
DAVISON...WPC (USA)
$$







000
FXCA20 KWBC 291153
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
652 AM EST THU JAN 29 2015

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI. BROAD POLAR
TROUGH ACROSS THE WESTERN NORTH ATLANTIC SUSTAINS A SURFACE FRONT
THAT TRAILS ACROSS NORTHERN HISPANIOLA TO THE NORTHWEST CARIBBEAN.
FURTHERMORE...UNDER INFLUENCE OF THE DEEP POLAR TROUGH PATTERN TO
THE NORTH...AN INDUCED/ INVERTED TROUGH NOW EXTENDS OVER THE
EASTERN CARIBBEAN ALONG 63W/64W. ALSO...A SHEAR LINE EXTENDS
ACROSS EASTERN HISPANIOLA TO THE SOUTHERN CARIBBEAN. MOST ACTIVE
CONVECTION IS DEVELOPING IN ASSOCIATION WITH THE SURFACE FRONT AS
IT MEANDERS ALONG THE NORTH COAST OF HISPANIOLA.

UPPER LEVEL TROUGH IS EXPECTED TO PULL AWAY THROUGH FRIDAY
MORNING. ON ITS WAKE...A RIDGE IS TO GRADUALLY ESTABLISH OVER
NORTHERN SOUTH AMERICA/CARIBBEAN TO THE GREATER ANTILLES-THE
BAHAMAS. AS THE RIDGE BUILDS...TRADE WINDS CAP IS TO GRADUALLY
STRENGTHEN THROUGH MIDDAY ON FRIDAY. THIS IS TO THEN HOLD THROUGH
THE WEEKEND/EARLY NEXT WEEK. BEST CHANCE FOR CONVECTION MIGHT BE
TODAY-EARLY FRIDAY MORNING AS THE BASE OF THE MID LEVEL TROUGH AND
A WEEK CYCLONIC MAXIMA GRAZE PUERTO RICO/NORTHERN VI. AT LOW
LEVELS...SURFACE FRONT IS EXPECTED TO STALL FAR TO THE NORTH...AND
GRADUALLY WEAKEN/FRONTOLIZE DURING THE WEEKEND. SHEAR LINE IS TO
MEANDER OVER THE FORECAST AREA DURING THE NEXT COUPLE OF DAYS. BUT
LACKING UPPER LEVEL SUPPORT IT IS NOT EXPECTED TO TRIGGER
SIGNIFICANT CONVECTION. PER THE HIGH RESOLUTION MODELS...IT LOOKS
LIKE MEASURABLE RAINFALL AMOUNTS ARE TO CONFINE TO THE
CENTRAL/WESTERN PORTIONS OF THE CORDILLERA OVER PUERTO RICO...WITH
LIGHT CONVECTION POSSIBLE ALONG THE NORTH COAST AS THE OCCASIONAL
TRADE WIND SHOWER STREAMS ACROSS THE FORECAST AREA.

ANOTHER FRONT IS TO CLEAR THE EASTERN SEABOARD OF THE USA EARLY ON
FRIDAY...BUT THIS IS TO STALL FAR TO THE NORTH. BUILDING POLAR
RIDGE TO THE WEST IS TO THEN SUSTAIN ANOTHER SHEAR LINE ACROSS THE
FORECAST AREA LATER ON SATURDAY...BUT THROUGH MIDDAY ON SUNDAY IT
IS TO CONTINUE FARTHER EAST AND SOUTH ACROSS THE FRENCH ISLES AS
BROAD RIDGE SETTLES TO THE NORTH. BRISK NORTHEASTERLY TRADES ARE
TO ACCOMPANY THIS FEATURE...WITH WINDY CONDITIONS LIKELY TO
PERSIST THROUGH MONDAY EVENING/EARLY TUESDAY MORNING. GLOBAL
MODELS GENERALLY AGREE ON POTENTIAL FOR SCATTERED SHOWERS TO
ACCOMPANY THIS FEATURE AS IT ENTERS PUERTO RICO LATER ON
SATURDAY...WITH BOTH EUROPEAN MODELS SHOWING A SOMEWHAT MORE
ACTIVE PATTERN THAN WHAT THE GFS SUGGESTS.

JN BAPTISTE...MS (SAINT LUCIA)
NANDA...MDS (SURINAME)
DAVISON...WPC (USA)
$$






000
FXUS01 KWBC 290812
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
312 AM EST THU JAN 29 2015

VALID 12Z THU JAN 29 2015 - 12Z SAT JAN 31 2015

***MORE WINTRY WEATHER FROM GREAT LAKES TO THE NORTHEAST***

***MUCH COLDER WEATHER ARRIVING TO THE GREAT PLAINS STATES***

***MOISTURE INCREASING FOR THE SOUTHWESTERN U.S.***

AFTER A BRIEF RESPITE IN THE WEATHER FOR THE NORTHEAST AND
MID-ATLANTIC REGION, ANOTHER ROUND OF SNOW IS FORECAST FROM THE
UPPER GREAT LAKES TO NEW ENGLAND ON THURSDAY AND MOVING OFFSHORE
ON FRIDAY.  A MIX OF RAIN AND SNOW IS LIKELY FROM KENTUCKY TO
WASHINGTON DC SINCE TEMPERATURES WILL BE MORE MARGINAL IN THESE
AREAS.  THIS EVENT WILL BE CONSIDERABLY WEAKER THAN ITS MONSTER
PREDECESSOR A FEW DAYS AGO, WITH MOST LOCATIONS GETTING LESS THAN
SIX INCHES OF SNOW.  THE EXCEPTION WILL LIKELY BE OVER MAINE,
WHERE GREATER SNOWFALL AMOUNTS ARE POSSIBLE.

AFTER WIDESPREAD HIGH TEMPERATURES IN THE 70S AND EVEN LOW 80S
OVER THE CENTRAL AND SOUTHERN PLAINS EARLIER THIS WEEK, EXPECT
MUCH COOLER TEMPERATURES TO ARRIVE AS A STRONG SURFACE HIGH SLIDES
DOWN FROM CANADA BEHIND A COLD FRONT AND EXPANDS OVER MUCH OF THE
CENTRAL U.S. TO CLOSE OUT THE WORK WEEK.  HIGHS WILL BE CLOSER TO
AVERAGE FOR THIS TIME OF YEAR, ALONG WITH GUSTY WINDS.

CONDITIONS WILL BECOME INCREASINGLY WET OVER THE SOUTHWEST AND
FOUR CORNERS REGION FOR THE NEXT FEW DAYS WHILE AN ELONGATED UPPER
TROUGH EDGES INLAND OVER NORTHERN MEXICO AND STRONG LOW-LEVEL
WINDS ADVECT INCREASING PACIFIC MOISTURE TO THESE AREAS.  THIS
MOISTURE WILL FUEL WIDESPREAD MODERATE TO LOCALLY HEAVY
PRECIPITATION, WITH THE GREATEST AMOUNTS EXPECTED FOR ARIZONA AND
NEW MEXICO.  ACCUMULATING SNOW IS EXPECTED FOR THE HIGHER
ELEVATIONS OF UTAH, COLORADO, AND NEW MEXICO, AND A MIX OF RAIN
AND SNOW FOR THE HIGHER ELEVATIONS OF ARIZONA.

HAMRICK


GRAPHICS AVAILABLE AT WWW.WPC.NCEP.NOAA.GOV
$$






000
FXUS02 KWBC 290522
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1222 AM EST THU JAN 29 2015

VALID 12Z SUN FEB 01 2015 - 12Z THU FEB 05 2015

...PATTERN OVERVIEW...

IT REMAINS THE CASE THAT GUIDANCE IS STILL PRETTY CONSISTENT WITH
THE IDEA OF MAINTAINING A MEAN RIDGE NEAR THE WEST COAST...WITH
ONLY BRIEF FLATTENING AROUND EARLY NEXT WEEK AS SOME PACIFIC
ENERGY FILTERS THROUGH AND HEADS INTO A BROADENING CONUS MEAN
TROUGH. THE CONUS MEAN TROUGH SEEN IN MOST SOLNS BY THE MIDDLE OF
NEXT WEEK HAS BETTER THAN AVG CONFIDENCE IN LIGHT OF UPSTREAM FLOW
AMPLITUDE. IN ADVANCE OF THIS EVOLUTION HOWEVER...MODEL/ENSEMBLE
SPREAD SUGGESTS CONTINUED LESS THAN AVG CONFIDENCE WITH THE
PARTICULARS OF SYSTEMS AFFECTING AREAS FROM THE FOUR
CORNERS/PLAINS NEWD INTO THE EAST THIS WEEKEND INTO MON AND
SUBSEQUENT SECONDARY COLD AIR SURGES DIGGING INTO THE N-CENTRAL US
FROM CANADA.

...GUIDANCE/UNCERTAINTY EVALUATION AND PREFERENCES...

AS INDICATED YESTERDAY...THERE CONTINUE TO BE VARIOUS SOURCES OF
UNCERTAINTY FOR THE SYSTEM EXPECTED TO AFFECT THE CNTRL-ERN STATES
FROM THE WEEKEND INTO THE START OF NEXT WEEK.  SUPPORTING ENERGY
AMPLIFYING INTO THE PLAINS DURING THE WEEKEND ORIGINATES FROM A
COMBINATION OF FLAT FLOW HEADING INTO BC AND SHEARED ENERGY OVER
ALASKA IN THE SHORT RANGE. THESE IMPULSES DO NOT REACH WRN CANADA
UNTIL LATE FRI SO IT MAY TAKE UNTIL AT LEAST THEN TO GET A
REASONABLE ANALYSIS OF THIS ENERGY. BEYOND THIS ISSUE IS THE
QUESTION OF NRN STREAM TROUGH AMPLITUDE OVER THE CONUS AND HOW
MUCH INTERACTION THERE IS WITH THE TROUGH OVER THE SWRN CONUS/NRN
MEXICO AND EJECTING SRN STREAM IMPLUSES.

SIGNIFICANT MODEL RUN TO RUN WAFFLING OVER THE PAST COUPLE OF DAYS
LENDS WPC PREFERENCE OF A COMPOSITE GUIDANCE SOLUTION LEANING
HEAVILY ON THE COMPARATIVELY CONSISTENT AND COMPATABLE 18 UTC GEFS
MEAN AND 12 UTC ECMWF ENSEMBLE MEAN.

...SENSIBLE WEATHER HIGHLIGHTS...

AN EXPANDING PCPN SHIELD WILL SPREAD NEWD FROM THE SRN PLAINS NEWD
THROUGH THE ERN US...MAINLY WITH THIS ROUND CLEARING THE COAST
EARLY NEXT WEEK ALONG WITH THE WAVY FRONT. GUIDANCE HAS STILL NOT
YET STABILIZED ON A PARTICULAR SOLUTION SO CONFIDENCE REMAINS MUCH
LOWER THAN DESIRED WITH PLACEMENT OF PCPN TYPES FOR THIS SYSTEM.
HOWEVER...FULLY EXPECT A SWATH OF ORGANIZED SNOWS ON THE NRN
PERIPHERY OF THE EXPANDING PCPN SHIELD WITH A MIX OF
PCPN/TRANSITION ZONE JUST S. WPC WEATHER/PRECIPIATION TYPE
GRIDS/GRAPHICS OFFER OUR BEST ESTIMATE FOR THIS THREAT AT THIS
TIME BASED FROM LATEST GUIDANCE PREFERENCES. LOCATIONS WITHIN THE
BROAD PCPN AREA MAY SEE LOCALLY HEAVY AMOUNTS. PASSAGE OF THIS
SYSTEM SHOULD SUPPORT A PERIOD OF LAKE EFFECT SNOW. SECONDARY COLD
SURGES IN THE WAKE OF THE LEAD SYSTEM WILL DIG DEEP INTO THE
CENTRAL AND  ERN US IN AMPLIFIED NRN STREAM FLOW ALONG WITH MODEST
LEAD CLIPPER LOW TO MID-ATLANTIC/NEW ENG COASTAL LOW DEVELOPMENT
TRACK AND SNOW SWATH. MEANWHILE...DRY CONDS ACROSS THE NW QUARTER
OF THE COUNTRY INLAND TO THE ROCKIES WILL TREND WETTER BY EARLY
NEXT WEEK AS ERN PAC ENERGY SLIPS THROUGH THE LONGER TERM MEAN
RIDGE ALOFT...ESPECIALLY OVER FAVORED TERRAIN.

SCHICHTEL

$$






000
FXUS02 KWBC 290522
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1222 AM EST THU JAN 29 2015

VALID 12Z SUN FEB 01 2015 - 12Z THU FEB 05 2015

...PATTERN OVERVIEW...

IT REMAINS THE CASE THAT GUIDANCE IS STILL PRETTY CONSISTENT WITH
THE IDEA OF MAINTAINING A MEAN RIDGE NEAR THE WEST COAST...WITH
ONLY BRIEF FLATTENING AROUND EARLY NEXT WEEK AS SOME PACIFIC
ENERGY FILTERS THROUGH AND HEADS INTO A BROADENING CONUS MEAN
TROUGH. THE CONUS MEAN TROUGH SEEN IN MOST SOLNS BY THE MIDDLE OF
NEXT WEEK HAS BETTER THAN AVG CONFIDENCE IN LIGHT OF UPSTREAM FLOW
AMPLITUDE. IN ADVANCE OF THIS EVOLUTION HOWEVER...MODEL/ENSEMBLE
SPREAD SUGGESTS CONTINUED LESS THAN AVG CONFIDENCE WITH THE
PARTICULARS OF SYSTEMS AFFECTING AREAS FROM THE FOUR
CORNERS/PLAINS NEWD INTO THE EAST THIS WEEKEND INTO MON AND
SUBSEQUENT SECONDARY COLD AIR SURGES DIGGING INTO THE N-CENTRAL US
FROM CANADA.

...GUIDANCE/UNCERTAINTY EVALUATION AND PREFERENCES...

AS INDICATED YESTERDAY...THERE CONTINUE TO BE VARIOUS SOURCES OF
UNCERTAINTY FOR THE SYSTEM EXPECTED TO AFFECT THE CNTRL-ERN STATES
FROM THE WEEKEND INTO THE START OF NEXT WEEK.  SUPPORTING ENERGY
AMPLIFYING INTO THE PLAINS DURING THE WEEKEND ORIGINATES FROM A
COMBINATION OF FLAT FLOW HEADING INTO BC AND SHEARED ENERGY OVER
ALASKA IN THE SHORT RANGE. THESE IMPULSES DO NOT REACH WRN CANADA
UNTIL LATE FRI SO IT MAY TAKE UNTIL AT LEAST THEN TO GET A
REASONABLE ANALYSIS OF THIS ENERGY. BEYOND THIS ISSUE IS THE
QUESTION OF NRN STREAM TROUGH AMPLITUDE OVER THE CONUS AND HOW
MUCH INTERACTION THERE IS WITH THE TROUGH OVER THE SWRN CONUS/NRN
MEXICO AND EJECTING SRN STREAM IMPLUSES.

SIGNIFICANT MODEL RUN TO RUN WAFFLING OVER THE PAST COUPLE OF DAYS
LENDS WPC PREFERENCE OF A COMPOSITE GUIDANCE SOLUTION LEANING
HEAVILY ON THE COMPARATIVELY CONSISTENT AND COMPATABLE 18 UTC GEFS
MEAN AND 12 UTC ECMWF ENSEMBLE MEAN.

...SENSIBLE WEATHER HIGHLIGHTS...

AN EXPANDING PCPN SHIELD WILL SPREAD NEWD FROM THE SRN PLAINS NEWD
THROUGH THE ERN US...MAINLY WITH THIS ROUND CLEARING THE COAST
EARLY NEXT WEEK ALONG WITH THE WAVY FRONT. GUIDANCE HAS STILL NOT
YET STABILIZED ON A PARTICULAR SOLUTION SO CONFIDENCE REMAINS MUCH
LOWER THAN DESIRED WITH PLACEMENT OF PCPN TYPES FOR THIS SYSTEM.
HOWEVER...FULLY EXPECT A SWATH OF ORGANIZED SNOWS ON THE NRN
PERIPHERY OF THE EXPANDING PCPN SHIELD WITH A MIX OF
PCPN/TRANSITION ZONE JUST S. WPC WEATHER/PRECIPIATION TYPE
GRIDS/GRAPHICS OFFER OUR BEST ESTIMATE FOR THIS THREAT AT THIS
TIME BASED FROM LATEST GUIDANCE PREFERENCES. LOCATIONS WITHIN THE
BROAD PCPN AREA MAY SEE LOCALLY HEAVY AMOUNTS. PASSAGE OF THIS
SYSTEM SHOULD SUPPORT A PERIOD OF LAKE EFFECT SNOW. SECONDARY COLD
SURGES IN THE WAKE OF THE LEAD SYSTEM WILL DIG DEEP INTO THE
CENTRAL AND  ERN US IN AMPLIFIED NRN STREAM FLOW ALONG WITH MODEST
LEAD CLIPPER LOW TO MID-ATLANTIC/NEW ENG COASTAL LOW DEVELOPMENT
TRACK AND SNOW SWATH. MEANWHILE...DRY CONDS ACROSS THE NW QUARTER
OF THE COUNTRY INLAND TO THE ROCKIES WILL TREND WETTER BY EARLY
NEXT WEEK AS ERN PAC ENERGY SLIPS THROUGH THE LONGER TERM MEAN
RIDGE ALOFT...ESPECIALLY OVER FAVORED TERRAIN.

SCHICHTEL

$$







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