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000
FXUS02 KWBC 180427
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1126 PM EST WED DEC 17 2014

VALID 12Z SUN DEC 21 2014 - 12Z THU DEC 25 2014

...STRONG SYSTEM POSSIBLE IN THE EAST FOR CHRISTMAS EVE/DAY...


..OVERVIEW AND GUIDANCE PREFERENCES...

AMPLIFIED PATTERN SET TO RETURN TO THE US AS THE STRONG W PACIFIC
JET TRANSLATES DOWNSTREAM THIS WEEKEND INTO THE PAC NW. BUILDING
HEIGHTS OVER SE CANADA SHOULD ALSO HELP DIG THE TROUGH INTO THE
OHIO VALLEY MIDWEEK AND LIKELY CLOSE OFF AS IT SWINGS INTO
SOUTHERN CANADA ON CHRISTMAS DAY. MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT IN RECENT RUNS ON THIS AMPLIFIED PATTERN AND THE
MOST RECENT GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO
NEXT THURSDAY. ONGOING DIFFERENCE BETWEEN THE TWO IS A TYPICAL
ONE... WITH THE GEFS MEMBERS A BIT QUICKER WITH THE PATTERN THAN
THE ECMWF MEMBERS. AMPLIFIED PATTERN WOULD TYPICALLY FAVOR THE
SLOWER /ECMWF-LIKE/ SOLUTIONS BUT UPSTREAM PACIFIC ENERGY MAY BE
ENOUGH OF A KICKER TO KEEP THINGS MOVING. BLEND OF THE GUIDANCE...
GFS/ECMWF/GFS PARALLEL AND THEIR MEANS... SHOULD PROVE GOOD ENOUGH
BUT OPTED TO USE THE BETTER CLUSTERED 12Z ECMWF AND 18Z PARALLEL
GFS WITH THE ECMWF ENSEMBLE MEAN WHICH OFFERED A BIT MORE DETAIL.
HOWEVER... DESPITE THE GOOD AGREEMENT THE MODELS ALWAYS FIND A WAY
TO CHANGE THE DETAILS... WHICH WAS ONE REASON FOR TRENDING TOWARD
THE ECMWF ENSEMBLE MEAN BY THURSDAY. MONTHLY RECORD LOW SEA LEVEL
PRESSURE RECORDS COULD BE CHALLENGED IN SOME LOCATIONS OF THE
CENTRAL GREAT LAKES -- WHICH ARE NEAR 970 IN THE UP OF MICHIGAN TO
THE LOW 980S IN N OHIO. DEEPEST ENSEMBLE MEMBERS ARE IN THE 950S
MB RANGE WHICH IS IMPRESSIVE.

ALSO BY LATE IN THE PERIOD IS UPSTREAM KICKER ENERGY THAT MAY DIVE
DOWN INTO THE WEST. 12Z ECMWF REPRESENTS ABOUT THE STRONGEST SIDE
OF THE ENSEMBLE SPREAD. GIVEN THE FACT THAT THE SPAGHETTI CHARTS
OVER THE PACIFIC LOOK LIKE ABSTRACT ART... A TREND TOWARD THE
MEANS /ECMWF ENSEMBLE MEAN IN THIS CASE/ WORKED WELL AT BOTH ENDS
OF THE CONUS.


...SENSIBLE WEATHER HIGHLIGHTS...

OFF THE EAST COAST... THE PESKY SYSTEM THAT REFUSES TO BE
WELL-FORECAST MAY VERY WELL TAKE ITS TIME EXITING INTO THE
ATLANTIC. MODELS HAVE TRENDED TOWARD THIS WEAKER SOLUTION OVER THE
PAST SEVERAL DAYS AND THE LOW LEVEL BAROCLINIC ZONE MAY NOT BUDGE
PAST THE GULF STREAM AS THE FLOW TURNS SOUTHWESTERLY/PARALLEL TO
THE FRONT. SOME LIGHT RAIN/SNOW IS STILL POSSIBLE BACK INTO THE
MID-ATLANTIC/NORTHEAST UNTIL IT PUSHES NORTHEASTWARD AND
DISSIPATES MIDWEEK.

DEVELOPING SYSTEM IN THE CENTRAL/EASTERN CONUS DEC 23-24 MAY STEAL
THE HEADLINES GIVEN ITS TIMING. MOST PRECIP WILL BE LIQUID WITH A
DEEP SUBTROPICAL CONNECTION BACK ACROSS MEXICO... PW ANOMALIES
FORECAST TO RISE TO BETWEEN +1 TO +3 /OR HIGHER/... AND
TEMPERATURES WELL ABOVE AVERAGE. AS THE SYSTEM WRAPS UP INTO
CANADA... COLD AIR ADVECTION SHOULD CIRCULATE AROUND THROUGH THE
LAKES AND OHIO VALLEY EASTWARD ON WEST TO SOUTHWEST FLOW... FIRING
UP THE LAKE MACHINE.


FRACASSO

$$






000
FXUS02 KWBC 180427
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1126 PM EST WED DEC 17 2014

VALID 12Z SUN DEC 21 2014 - 12Z THU DEC 25 2014

...STRONG SYSTEM POSSIBLE IN THE EAST FOR CHRISTMAS EVE/DAY...


..OVERVIEW AND GUIDANCE PREFERENCES...

AMPLIFIED PATTERN SET TO RETURN TO THE US AS THE STRONG W PACIFIC
JET TRANSLATES DOWNSTREAM THIS WEEKEND INTO THE PAC NW. BUILDING
HEIGHTS OVER SE CANADA SHOULD ALSO HELP DIG THE TROUGH INTO THE
OHIO VALLEY MIDWEEK AND LIKELY CLOSE OFF AS IT SWINGS INTO
SOUTHERN CANADA ON CHRISTMAS DAY. MODELS/ENSEMBLES HAVE BEEN
FAIRLY CONSISTENT IN RECENT RUNS ON THIS AMPLIFIED PATTERN AND THE
MOST RECENT GEFS/ECMWF ENSEMBLE GUIDANCE SHOW GOOD CORRELATION TO
NEXT THURSDAY. ONGOING DIFFERENCE BETWEEN THE TWO IS A TYPICAL
ONE... WITH THE GEFS MEMBERS A BIT QUICKER WITH THE PATTERN THAN
THE ECMWF MEMBERS. AMPLIFIED PATTERN WOULD TYPICALLY FAVOR THE
SLOWER /ECMWF-LIKE/ SOLUTIONS BUT UPSTREAM PACIFIC ENERGY MAY BE
ENOUGH OF A KICKER TO KEEP THINGS MOVING. BLEND OF THE GUIDANCE...
GFS/ECMWF/GFS PARALLEL AND THEIR MEANS... SHOULD PROVE GOOD ENOUGH
BUT OPTED TO USE THE BETTER CLUSTERED 12Z ECMWF AND 18Z PARALLEL
GFS WITH THE ECMWF ENSEMBLE MEAN WHICH OFFERED A BIT MORE DETAIL.
HOWEVER... DESPITE THE GOOD AGREEMENT THE MODELS ALWAYS FIND A WAY
TO CHANGE THE DETAILS... WHICH WAS ONE REASON FOR TRENDING TOWARD
THE ECMWF ENSEMBLE MEAN BY THURSDAY. MONTHLY RECORD LOW SEA LEVEL
PRESSURE RECORDS COULD BE CHALLENGED IN SOME LOCATIONS OF THE
CENTRAL GREAT LAKES -- WHICH ARE NEAR 970 IN THE UP OF MICHIGAN TO
THE LOW 980S IN N OHIO. DEEPEST ENSEMBLE MEMBERS ARE IN THE 950S
MB RANGE WHICH IS IMPRESSIVE.

ALSO BY LATE IN THE PERIOD IS UPSTREAM KICKER ENERGY THAT MAY DIVE
DOWN INTO THE WEST. 12Z ECMWF REPRESENTS ABOUT THE STRONGEST SIDE
OF THE ENSEMBLE SPREAD. GIVEN THE FACT THAT THE SPAGHETTI CHARTS
OVER THE PACIFIC LOOK LIKE ABSTRACT ART... A TREND TOWARD THE
MEANS /ECMWF ENSEMBLE MEAN IN THIS CASE/ WORKED WELL AT BOTH ENDS
OF THE CONUS.


...SENSIBLE WEATHER HIGHLIGHTS...

OFF THE EAST COAST... THE PESKY SYSTEM THAT REFUSES TO BE
WELL-FORECAST MAY VERY WELL TAKE ITS TIME EXITING INTO THE
ATLANTIC. MODELS HAVE TRENDED TOWARD THIS WEAKER SOLUTION OVER THE
PAST SEVERAL DAYS AND THE LOW LEVEL BAROCLINIC ZONE MAY NOT BUDGE
PAST THE GULF STREAM AS THE FLOW TURNS SOUTHWESTERLY/PARALLEL TO
THE FRONT. SOME LIGHT RAIN/SNOW IS STILL POSSIBLE BACK INTO THE
MID-ATLANTIC/NORTHEAST UNTIL IT PUSHES NORTHEASTWARD AND
DISSIPATES MIDWEEK.

DEVELOPING SYSTEM IN THE CENTRAL/EASTERN CONUS DEC 23-24 MAY STEAL
THE HEADLINES GIVEN ITS TIMING. MOST PRECIP WILL BE LIQUID WITH A
DEEP SUBTROPICAL CONNECTION BACK ACROSS MEXICO... PW ANOMALIES
FORECAST TO RISE TO BETWEEN +1 TO +3 /OR HIGHER/... AND
TEMPERATURES WELL ABOVE AVERAGE. AS THE SYSTEM WRAPS UP INTO
CANADA... COLD AIR ADVECTION SHOULD CIRCULATE AROUND THROUGH THE
LAKES AND OHIO VALLEY EASTWARD ON WEST TO SOUTHWEST FLOW... FIRING
UP THE LAKE MACHINE.


FRACASSO

$$







000
FXUS01 KWBC 172100
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
359 PM EST WED DEC 17 2014

VALID 00Z THU DEC 18 2014 - 00Z SAT DEC 20 2014


...A SLOW-MOVING STORM IS EXPECTED TO DELIVER UP TO A FOOT OF SNOW
IN NORTHERN NEW ENGLAND...

...FINE WEATHER PREVAILS IN THE NORTHERN AND EASTERN U.S. WHILE A
NEW STORM WILL BEGIN TO FORM IN THE SOUTHERN PLAINS...

...OCCASIONAL MOUNTAIN SNOW AND COASTAL RAIN SHOWERS ARE EXPECTED
IN THE WESTERN U.S....

THE SHORT-TERM FORECAST PERIOD BEGINS WITH AN INTENSIFYING COASTAL
STORM OVER THE GULF OF MAINE.  THE STORM CENTER IS FORECAST TO
PASS JUST EAST OF NEW ENGLAND, MOVING SLOWLY INTO THE CANADIAN
MARITIMES OVER THE NEXT COUPLE OF DAYS.  SNOW IS EXPECTED TO
ACCUMULATE TO THE NORTH AND WEST OF THE STORM TRACK, BRINGING UP
TO A FOOT OF SNOW IN NORTHERN NEW ENGLAND.  THE SNOW SHOULD TAPER
OFF EARLY ON FRIDAY AND SHOULD END LATER IN THE DAY AS THE STORM
MOVES FAR ENOUGH TO THE EAST.

A HIGH PRESSURE SYSTEM IS PROVIDING FINE WEATHER WITH MILDER THAN
NORMAL TEMPERATURES ACROSS THE NORTHERN U.S., THE OHIO VALLEY AND
INTO THE EASTERN U.S.  MEANWHILE MOISTURE IS GATHERING IN THE
CENTRAL AND SOUTHERN PLAINS AHEAD OF AN UPPER-LEVEL TROUGH.  SOME
SNOW AND MIXED PRECIPITATION CAN BE EXPECTED ACROSS THE CENTRAL
PLAINS AND MID-MISSISSIPPI VALLEY TONIGHT INTO EARLY THURSDAY.
HOWEVER, THE ENTIRE BATCH OF PRECIPITATION IS FORECAST TO COLLAPSE
DURING THE DAY ON THURSDAY AS THE UPPER-LEVEL TROUGH LOSES SUPPORT
AND DE-AMPLIFIES. FARTHER TO THE SOUTH, MOISTURE FROM THE GULF OF
MEXICO WILL BEGIN TO GATHER ALONG A STATIONARY FRONT NEAR THE
TEXAS COAST WHERE A NEW LOW PRESSURE CENTER IS FORECAST TO
DEVELOP.  THE DEVELOPMENT WILL BEGIN TO ACCELERATE AS UPPER-LEVEL
ENERGY COMING FROM THE SOUTHERN ROCKIES IS INJECTED INTO THE
SYSTEM.  IT APPEARS THAT SHOWERS AND THUNDERSTORMS WILL BECOME
HEAVIER AND MORE WIDESPREAD IN SOUTHERN TEXAS THURSDAY NIGHT WHICH
WILL BE SPREADING EASTWARD INTO THE CENTRAL GULF STATES ON FRIDAY.

OVER THE WESTERN U.S., PIECES OF ENERGY ASSOCIATED WITH WEAKENING
LOWS AND FRONTAL SYSTEMS FROM THE PACIFIC WILL BRING OCCASIONAL
SNOW SHOWERS OVER THE INTERIOR MOUNTAINS, PARTICULARLY THE
SOUTHERN ROCKIES AND INTERMOUNTAIN WEST THROUGH FRIDAY.  MODERATE
AMOUNTS OF RAINFALL CAN BE EXPECTED IN COASTAL NORTHERN CALIFORNIA
TONIGHT AS WELL AS THE PACIFIC NORTHWEST THURSDAY NIGHT INTO
FRIDAY WITH THE ARRIVAL OF A NEW PACIFIC FRONT.

NO REAL COLD AIR IS IN SIGHT FOR THE ENTIRE CONTINENTAL U.S.
THROUGH FRIDAY.  IN FACT, TEMPERATURES ARE FORECAST TO BE MORE
THAN 10 DEGREES ABOVE NORMAL IN THE NORTHERN ROCKIES, NORTHERN
PLAINS AS WELL AS THE WESTERN GULF COAST.

KONG


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






000
FXUS01 KWBC 172100
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
359 PM EST WED DEC 17 2014

VALID 00Z THU DEC 18 2014 - 00Z SAT DEC 20 2014


...A SLOW-MOVING STORM IS EXPECTED TO DELIVER UP TO A FOOT OF SNOW
IN NORTHERN NEW ENGLAND...

...FINE WEATHER PREVAILS IN THE NORTHERN AND EASTERN U.S. WHILE A
NEW STORM WILL BEGIN TO FORM IN THE SOUTHERN PLAINS...

...OCCASIONAL MOUNTAIN SNOW AND COASTAL RAIN SHOWERS ARE EXPECTED
IN THE WESTERN U.S....

THE SHORT-TERM FORECAST PERIOD BEGINS WITH AN INTENSIFYING COASTAL
STORM OVER THE GULF OF MAINE.  THE STORM CENTER IS FORECAST TO
PASS JUST EAST OF NEW ENGLAND, MOVING SLOWLY INTO THE CANADIAN
MARITIMES OVER THE NEXT COUPLE OF DAYS.  SNOW IS EXPECTED TO
ACCUMULATE TO THE NORTH AND WEST OF THE STORM TRACK, BRINGING UP
TO A FOOT OF SNOW IN NORTHERN NEW ENGLAND.  THE SNOW SHOULD TAPER
OFF EARLY ON FRIDAY AND SHOULD END LATER IN THE DAY AS THE STORM
MOVES FAR ENOUGH TO THE EAST.

A HIGH PRESSURE SYSTEM IS PROVIDING FINE WEATHER WITH MILDER THAN
NORMAL TEMPERATURES ACROSS THE NORTHERN U.S., THE OHIO VALLEY AND
INTO THE EASTERN U.S.  MEANWHILE MOISTURE IS GATHERING IN THE
CENTRAL AND SOUTHERN PLAINS AHEAD OF AN UPPER-LEVEL TROUGH.  SOME
SNOW AND MIXED PRECIPITATION CAN BE EXPECTED ACROSS THE CENTRAL
PLAINS AND MID-MISSISSIPPI VALLEY TONIGHT INTO EARLY THURSDAY.
HOWEVER, THE ENTIRE BATCH OF PRECIPITATION IS FORECAST TO COLLAPSE
DURING THE DAY ON THURSDAY AS THE UPPER-LEVEL TROUGH LOSES SUPPORT
AND DE-AMPLIFIES. FARTHER TO THE SOUTH, MOISTURE FROM THE GULF OF
MEXICO WILL BEGIN TO GATHER ALONG A STATIONARY FRONT NEAR THE
TEXAS COAST WHERE A NEW LOW PRESSURE CENTER IS FORECAST TO
DEVELOP.  THE DEVELOPMENT WILL BEGIN TO ACCELERATE AS UPPER-LEVEL
ENERGY COMING FROM THE SOUTHERN ROCKIES IS INJECTED INTO THE
SYSTEM.  IT APPEARS THAT SHOWERS AND THUNDERSTORMS WILL BECOME
HEAVIER AND MORE WIDESPREAD IN SOUTHERN TEXAS THURSDAY NIGHT WHICH
WILL BE SPREADING EASTWARD INTO THE CENTRAL GULF STATES ON FRIDAY.

OVER THE WESTERN U.S., PIECES OF ENERGY ASSOCIATED WITH WEAKENING
LOWS AND FRONTAL SYSTEMS FROM THE PACIFIC WILL BRING OCCASIONAL
SNOW SHOWERS OVER THE INTERIOR MOUNTAINS, PARTICULARLY THE
SOUTHERN ROCKIES AND INTERMOUNTAIN WEST THROUGH FRIDAY.  MODERATE
AMOUNTS OF RAINFALL CAN BE EXPECTED IN COASTAL NORTHERN CALIFORNIA
TONIGHT AS WELL AS THE PACIFIC NORTHWEST THURSDAY NIGHT INTO
FRIDAY WITH THE ARRIVAL OF A NEW PACIFIC FRONT.

NO REAL COLD AIR IS IN SIGHT FOR THE ENTIRE CONTINENTAL U.S.
THROUGH FRIDAY.  IN FACT, TEMPERATURES ARE FORECAST TO BE MORE
THAN 10 DEGREES ABOVE NORMAL IN THE NORTHERN ROCKIES, NORTHERN
PLAINS AS WELL AS THE WESTERN GULF COAST.

KONG


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







000
FXUS06 KWBC 172011
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST WED DECEMBER 17 2014

6-10 DAY OUTLOOK FOR DEC 23 - 27 2014

TODAY`S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA HEIGHT PATTERN
FORECAST FOR THE 6-10 DAY PERIOD. ALL MODELS ARE FORECASTING A BUILDING RIDGE
OVER THE NORTHEAST PACIFIC AND ALASKA. COMPARED WITH YESTERDAY`S FORECAST, THE
DOWNSTREAM TROUGH SHIFTED EASTWARD PREDICTED OVER THE EASTERN CONUS. POSITIVE
500-HPA HEIGHT ANOMALIES ARE FORECAST ALONG THE WEST COAST, NEGATIVE 500-HPA
HEIGHT ANOMALIES ARE FORECAST FROM THE ROCKIES TO THE EAST COAST. THE ENSEMBLE
SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE FORECAST DOMAIN. TODAY`S
OFFICIAL 500-HPA HEIGHT MANUAL BLEND INCLUDED THE OPERATIONAL EUROPEAN MODEL
SINCE IT IS CONSISTENT WITH THE ENSEMBLE MEAN SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN AND NORTHEASTERN CONUS
NEAR THE FORECAST RIDGE AND AHEAD OF THE TROUGH, RESPECTIVELY. BELOW-NORMAL
TEMPERATURES ARE EXPECTED OVER THE NORTHERN PLAINS AS MUCH COLDER TEMPERATURES
ARE FORECAST TO ENTER THIS REGION BY DAY 8. WITH SST ANOMALIES BELOW-NORMAL IN
THE EASTERN GULF OF MEXICO, BELOW-NORMAL TEMPERATURES ARE FAVORED FOR FLORIDA.
ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED FOR ALASKA, AND THE
ALEUTIANS IN ASSOCIATION WITH THE SURFACE SOUTHWESTERLY FLOW, EAST OF THE LOW
PRESSURE SYSTEM OVER THE BERING SEA.

WITH A STRONG PACIFIC JET NEAR THE NORTHWEST COAST, ABOVE-MEDIAN PRECIPITATION
IS FAVORED FROM THE PACIFIC NORTHWEST TO THE NORTHERN ROCKIES AND NORTHERN
GREAT PLAINS. ABOVE-MEDIAN PRECIPITATION IS PREDICTED OVER THE GREAT LAKES,
OHIO VALLEY AND ATLANTIC COAST STATES IN ASSOCIATION WITH THE ACTIVE
LOWER-LEVEL JET AHEAD OF THE TROUGH. BELOW-MEDIAN PRECIPITATION CHANCES ARE
ENHANCED FOR THE SOUTHWESTERN CONUS AND WEST GULF COAST, UNDER THE INFLUENCE OF
THE RIDGE NEAR THE WEST COAST. ABOVE-MEDIAN PRECIPITATION CHANCES ARE ENHANCED
FOR WESTERN ALASKA AND THE ALEUTIANS, NEAR AND AHEAD OF THE PREDICTED TROUGH
OVER THE NORTH PACIFIC. BELOW-MEDIAN PRECIPITATION CHANCES ARE ENHANCED FOR
EASTERN ALASKA, AND THE PANHANDLE IN ASSOCIATION WITH THE RIDGE FORECAST OFF
THE WEST COAST OF NORTH AMERICA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF YESTERDAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 7,
20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 20% OF YESTERDAY`S
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, AND 20% OF TODAY`S OPERATIONAL 0Z
ECMWF CENTERED ON DAY 8


MODEL OF THE DAY: NO PREFERENCE

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD
AGREEMENT AMONG ENSEMBLE MEANS, OFFSET BY UNCERTAINTY WHEN COLDER TEMPERATURE
ENTER THE CONUS.

8-14 DAY OUTLOOK FOR DEC 25 - 31 2014

THE ENSEMBLE MEAN PREDICTIONS OF THE 500-HPA HEIGHT PATTERN FOR THE WEEK-2
PERIOD ARE IN FAIR AGREEMENT OVER NORTH AMERICA. A RIDGE IS PREDICTED OVER THE
GULF OF ALASKA, ASSOCIATED WITH POSITIVE 500-HPA HEIGHT ANOMALIES OFF THE WEST
COAST. A HIGHLY AMPLITUDE TROUGH IS ANTICIPATED OVER THE EASTERN CONUS, WITH
NEGATIVE 500-HPA HEIGHT ANOMALIES ACROSS MOST OF THE CONUS. THE ENSEMBLE
SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE FORECAST DOMAIN.

THERE ARE ENHANCED PROBABILITIES FOR NEAR- TO ABOVE-NORMAL TEMPERATURES FOR THE
SOUTHWESTERN CONUS, AHEAD OF THE RIDGE OFF THE WEST COAST. BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR MUCH OF THE NORTHERN, CENTRAL AND EASTERN CONUS
EXCEPT FOR NEW ENGLAND. THERE ARE ENHANCED PROBABILITIES FOR NEAR- TO
ABOVE-NORMAL TEMPERATURES FOR ALASKA RELATED TO THE SOUTHWESTERLY WINDS, EAST
OF THE SURFACE LOW PRESSURE OVER THE BERING SEA.

BELOW-MEDIAN PRECIPITATION IS FAVORED FOR THE WESTERN CONUS IN ASSOCIATION WITH
THE FORECAST RIDGE OFF THE WEST COAST. NEAR- TO ABOVE-MEDIAN PRECIPITATION IS
FAVORED FOR THE NORTHERN AND CENTRAL ROCKIES, THE NORTHERN GREAT PLAINS, THE
GREAT LAKES AND THE NEW ENGLAND, CONSISTENT WITH THE BIAS CORRECTED
PRECIPITATION FROM THE ECMWF ENSEMBLES AND GFS ENSEMBLES.  ABOVE-MEDIAN
PRECIPITATION IS ALSO FAVORED FOR THE SOUTHEASTERN CONUS AHEAD OF THE TROUGH.
THERE ARE ENHANCED PROBABILITIES OF NEAR- TO ABOVE-MEDIAN PRECIPITATION FOR
WESTERN ALASKA AND THE ALEUTIANS. BELOW-MEDIAN PRECIPITATION IS FAVORED FOR
EASTERN ALASKA AND THE PANHANDLE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF YESTERDAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 10, 20% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% OF YESTERDAY`S
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO FAIR MODEL AGREEMENT WITH SOME DISAGREEMENT BETWEEN TOOLS FROM THE ECMWF AND
GEFS ENSEMBLES.

FORECASTER: QIN GINGER ZHANG

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
DECEMBER 18

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:
19911230 - 19931215 - 19871128 - 19591225 - 20031224


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:
19911230 - 19931214 - 19871127 - 19591225 - 20031224


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 23 - 27 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 25 - 31 2014

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

$$





000
FXUS06 KWBC 172011
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST WED DECEMBER 17 2014

6-10 DAY OUTLOOK FOR DEC 23 - 27 2014

TODAY`S MODEL SOLUTIONS ARE IN GOOD AGREEMENT ON THE 500-HPA HEIGHT PATTERN
FORECAST FOR THE 6-10 DAY PERIOD. ALL MODELS ARE FORECASTING A BUILDING RIDGE
OVER THE NORTHEAST PACIFIC AND ALASKA. COMPARED WITH YESTERDAY`S FORECAST, THE
DOWNSTREAM TROUGH SHIFTED EASTWARD PREDICTED OVER THE EASTERN CONUS. POSITIVE
500-HPA HEIGHT ANOMALIES ARE FORECAST ALONG THE WEST COAST, NEGATIVE 500-HPA
HEIGHT ANOMALIES ARE FORECAST FROM THE ROCKIES TO THE EAST COAST. THE ENSEMBLE
SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE FORECAST DOMAIN. TODAY`S
OFFICIAL 500-HPA HEIGHT MANUAL BLEND INCLUDED THE OPERATIONAL EUROPEAN MODEL
SINCE IT IS CONSISTENT WITH THE ENSEMBLE MEAN SOLUTIONS.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN AND NORTHEASTERN CONUS
NEAR THE FORECAST RIDGE AND AHEAD OF THE TROUGH, RESPECTIVELY. BELOW-NORMAL
TEMPERATURES ARE EXPECTED OVER THE NORTHERN PLAINS AS MUCH COLDER TEMPERATURES
ARE FORECAST TO ENTER THIS REGION BY DAY 8. WITH SST ANOMALIES BELOW-NORMAL IN
THE EASTERN GULF OF MEXICO, BELOW-NORMAL TEMPERATURES ARE FAVORED FOR FLORIDA.
ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE ENHANCED FOR ALASKA, AND THE
ALEUTIANS IN ASSOCIATION WITH THE SURFACE SOUTHWESTERLY FLOW, EAST OF THE LOW
PRESSURE SYSTEM OVER THE BERING SEA.

WITH A STRONG PACIFIC JET NEAR THE NORTHWEST COAST, ABOVE-MEDIAN PRECIPITATION
IS FAVORED FROM THE PACIFIC NORTHWEST TO THE NORTHERN ROCKIES AND NORTHERN
GREAT PLAINS. ABOVE-MEDIAN PRECIPITATION IS PREDICTED OVER THE GREAT LAKES,
OHIO VALLEY AND ATLANTIC COAST STATES IN ASSOCIATION WITH THE ACTIVE
LOWER-LEVEL JET AHEAD OF THE TROUGH. BELOW-MEDIAN PRECIPITATION CHANCES ARE
ENHANCED FOR THE SOUTHWESTERN CONUS AND WEST GULF COAST, UNDER THE INFLUENCE OF
THE RIDGE NEAR THE WEST COAST. ABOVE-MEDIAN PRECIPITATION CHANCES ARE ENHANCED
FOR WESTERN ALASKA AND THE ALEUTIANS, NEAR AND AHEAD OF THE PREDICTED TROUGH
OVER THE NORTH PACIFIC. BELOW-MEDIAN PRECIPITATION CHANCES ARE ENHANCED FOR
EASTERN ALASKA, AND THE PANHANDLE IN ASSOCIATION WITH THE RIDGE FORECAST OFF
THE WEST COAST OF NORTH AMERICA.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 20% OF YESTERDAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 7,
20% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, 20% OF YESTERDAY`S
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7, AND 20% OF TODAY`S OPERATIONAL 0Z
ECMWF CENTERED ON DAY 8


MODEL OF THE DAY: NO PREFERENCE

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO GOOD
AGREEMENT AMONG ENSEMBLE MEANS, OFFSET BY UNCERTAINTY WHEN COLDER TEMPERATURE
ENTER THE CONUS.

8-14 DAY OUTLOOK FOR DEC 25 - 31 2014

THE ENSEMBLE MEAN PREDICTIONS OF THE 500-HPA HEIGHT PATTERN FOR THE WEEK-2
PERIOD ARE IN FAIR AGREEMENT OVER NORTH AMERICA. A RIDGE IS PREDICTED OVER THE
GULF OF ALASKA, ASSOCIATED WITH POSITIVE 500-HPA HEIGHT ANOMALIES OFF THE WEST
COAST. A HIGHLY AMPLITUDE TROUGH IS ANTICIPATED OVER THE EASTERN CONUS, WITH
NEGATIVE 500-HPA HEIGHT ANOMALIES ACROSS MOST OF THE CONUS. THE ENSEMBLE
SPAGHETTI DIAGRAMS INDICATE MODERATE SPREAD ACROSS THE FORECAST DOMAIN.

THERE ARE ENHANCED PROBABILITIES FOR NEAR- TO ABOVE-NORMAL TEMPERATURES FOR THE
SOUTHWESTERN CONUS, AHEAD OF THE RIDGE OFF THE WEST COAST. BELOW-NORMAL
TEMPERATURES ARE FAVORED FOR MUCH OF THE NORTHERN, CENTRAL AND EASTERN CONUS
EXCEPT FOR NEW ENGLAND. THERE ARE ENHANCED PROBABILITIES FOR NEAR- TO
ABOVE-NORMAL TEMPERATURES FOR ALASKA RELATED TO THE SOUTHWESTERLY WINDS, EAST
OF THE SURFACE LOW PRESSURE OVER THE BERING SEA.

BELOW-MEDIAN PRECIPITATION IS FAVORED FOR THE WESTERN CONUS IN ASSOCIATION WITH
THE FORECAST RIDGE OFF THE WEST COAST. NEAR- TO ABOVE-MEDIAN PRECIPITATION IS
FAVORED FOR THE NORTHERN AND CENTRAL ROCKIES, THE NORTHERN GREAT PLAINS, THE
GREAT LAKES AND THE NEW ENGLAND, CONSISTENT WITH THE BIAS CORRECTED
PRECIPITATION FROM THE ECMWF ENSEMBLES AND GFS ENSEMBLES.  ABOVE-MEDIAN
PRECIPITATION IS ALSO FAVORED FOR THE SOUTHEASTERN CONUS AHEAD OF THE TROUGH.
THERE ARE ENHANCED PROBABILITIES OF NEAR- TO ABOVE-MEDIAN PRECIPITATION FOR
WESTERN ALASKA AND THE ALEUTIANS. BELOW-MEDIAN PRECIPITATION IS FAVORED FOR
EASTERN ALASKA AND THE PANHANDLE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20% OF TODAY`S 0Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 20% OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY
11, 20% OF YESTERDAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 10, 20% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11, AND 20% OF YESTERDAY`S
12Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 10


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE
TO FAIR MODEL AGREEMENT WITH SOME DISAGREEMENT BETWEEN TOOLS FROM THE ECMWF AND
GEFS ENSEMBLES.

FORECASTER: QIN GINGER ZHANG

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
DECEMBER 18

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:
19911230 - 19931215 - 19871128 - 19591225 - 20031224


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:
19911230 - 19931214 - 19871127 - 19591225 - 20031224


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 23 - 27 2014

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR DEC 25 - 31 2014

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

$$






000
FXUS02 KWBC 171938
PMDEPD

EXTENDED FORECAST DISCUSSION...CORRECTED PARAGRAPH 3
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1100 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...

..OVERVIEW...
ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A NEGATIVELY-TILTED TROUGH SETTING UP
OVER THE GREAT LAKES AND MID-ATLANTIC/NORTHEAST REGION(S) AROUND
THE CHRISTMAS EVE TIME FRAME.

A `BUCKLING` IN THE PERSISTENTLY-STRONG WESTERLY PACIFIC JET WILL
LIKELY OCCUR DURING WEEKEND---AND BECOME THE IMPETUS FOR
CHANGE---AMPLIFYING THE PATTERN DOWNSTREAM OVER THE LOWER 48. THE
17/00Z GEFS/ECENS MEANS HAVE WAVERED ON THE SMALLER-SCALE DETAILS
SURROUNDING THE PATTERN DOWNSTREAM OF THE ROCKIES...BUT GENERALLY
AGREE THAT A 500MB WAVE FORMS INVOF THE CENTRAL MIDWEST---WITH
PACIFIC JET SUPPORT CARVING OUT THE 200MB-500MB TROUGH TOWARDS THE
END OF THIS MEDIUM RANGE PERIOD.

...UNCERTAINTY ASSESSMENT...
AFOREMENTIONED `BUCKLING` OF THE PACIFIC JET ---IN THE OVERVIEW---
ALONG THE WEST COAST ON SAT/SUN APPEARED TO BE THE LEADING EDGE OF
A BROAD WARM FRONT THAT SURGES QUICKLY THROUGH THE NORTHERN
CONTINENTAL DIVIDE AND NORTHERN HIGH PLAINS. ON MONDAY...THE
FAST-MOVING NORTHWEST FLOW---NOSE OF THIS PACIFIC JET
CONFIGURATION ALOFT--SUPPORTS THE DEEPENING OF LEE SIDE
CYCLOGENESIS OVER SOUTHEASTERN ALBERTA AND THE BIRTH OF A
WELL-DEFINED SURFACE CYCLONE---MIGRATING ACROSS THE UPPER HALF OF
THE MISSOURI VALLEY EARLY IN THE PERIOD. ITS `MORPHOLOGY` AROUND
DAY 6...IN THE MIDWEST---APPEARS TO BE A FUNCTION OF ITS DEPTH AND
FORWARD MOTION IN RELATIONSHIP TO THE UPPER-LEVEL JET. ONE OF THE
SMALLER-SCALE DETAILS IS---CAN THE SURFACE CYCLONE DRAW UPON
ENOUGH COLDER...CANADIAN AIR AND PULL THAT COLDER AIRMASS
SOUTHEASTWARD FASTER/ENOUGH---TO INTENSIFY AND AMPLIFY---THE
ENTIRE PATTERN IN THE NORTHEAST QUARTER OF THE NATION---IN TIME
FOR THE PEAK CHRISTMAS TRAVEL `WINDOW`? THE SHORT ANSWER IS---YES.
DO THE 17/00Z DETERMINISTIC SOLUTIONS HAVE ALL THE `MORPHOLOGY`
DETAILS "DOWN PAT"---THE ANSWER IS NO. THE `NO` PART OF THE ANSWER
IS ON THE WINTER WEATHER SIDE--AND WHO MAY/MAY NOT SEE A `WHITE
CHRISTMAS` MORNING.

WHAT CAN BE GLEANED FROM THE 17/00Z GUIDANCE IS...THERE WILL BE A
DYNAMIC UPPER-LEVEL TROUGH EMERGING AND THE THREAT OF ORGANIZED
SYNOPTIC-SCALE PRECIPITATION ASSOCIATED WITH THE SURFACE
CYCLONE--WITH A DISTINCT WINTER SIDE---ALONG ITS NORTHERN
PERIPHERY---AND WET SIDE AHEAD OF THE DEEPER---COLD AIRMASS THAT
IS RAIN.

...MODEL PREFERENCES...
THE 17/00Z GEFS/ECENS AND THEIR DETERMINISTIC RUNS WERE IN DECENT
AGREEMENT THROUGH 22/12Z...AND WPC LIKES THE SLIGHTLY SLOWER ECENS
VERSUS THE GEFS AFTER DAY 5 FROM THE DATELINE TO THE EASTERN
SEABOARD.  VOJTESAK

...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.

FRACASSO

$$






000
FXUS02 KWBC 171938
PMDEPD

EXTENDED FORECAST DISCUSSION...CORRECTED PARAGRAPH 3
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1100 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...

..OVERVIEW...
ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A NEGATIVELY-TILTED TROUGH SETTING UP
OVER THE GREAT LAKES AND MID-ATLANTIC/NORTHEAST REGION(S) AROUND
THE CHRISTMAS EVE TIME FRAME.

A `BUCKLING` IN THE PERSISTENTLY-STRONG WESTERLY PACIFIC JET WILL
LIKELY OCCUR DURING WEEKEND---AND BECOME THE IMPETUS FOR
CHANGE---AMPLIFYING THE PATTERN DOWNSTREAM OVER THE LOWER 48. THE
17/00Z GEFS/ECENS MEANS HAVE WAVERED ON THE SMALLER-SCALE DETAILS
SURROUNDING THE PATTERN DOWNSTREAM OF THE ROCKIES...BUT GENERALLY
AGREE THAT A 500MB WAVE FORMS INVOF THE CENTRAL MIDWEST---WITH
PACIFIC JET SUPPORT CARVING OUT THE 200MB-500MB TROUGH TOWARDS THE
END OF THIS MEDIUM RANGE PERIOD.

...UNCERTAINTY ASSESSMENT...
AFOREMENTIONED `BUCKLING` OF THE PACIFIC JET ---IN THE OVERVIEW---
ALONG THE WEST COAST ON SAT/SUN APPEARED TO BE THE LEADING EDGE OF
A BROAD WARM FRONT THAT SURGES QUICKLY THROUGH THE NORTHERN
CONTINENTAL DIVIDE AND NORTHERN HIGH PLAINS. ON MONDAY...THE
FAST-MOVING NORTHWEST FLOW---NOSE OF THIS PACIFIC JET
CONFIGURATION ALOFT--SUPPORTS THE DEEPENING OF LEE SIDE
CYCLOGENESIS OVER SOUTHEASTERN ALBERTA AND THE BIRTH OF A
WELL-DEFINED SURFACE CYCLONE---MIGRATING ACROSS THE UPPER HALF OF
THE MISSOURI VALLEY EARLY IN THE PERIOD. ITS `MORPHOLOGY` AROUND
DAY 6...IN THE MIDWEST---APPEARS TO BE A FUNCTION OF ITS DEPTH AND
FORWARD MOTION IN RELATIONSHIP TO THE UPPER-LEVEL JET. ONE OF THE
SMALLER-SCALE DETAILS IS---CAN THE SURFACE CYCLONE DRAW UPON
ENOUGH COLDER...CANADIAN AIR AND PULL THAT COLDER AIRMASS
SOUTHEASTWARD FASTER/ENOUGH---TO INTENSIFY AND AMPLIFY---THE
ENTIRE PATTERN IN THE NORTHEAST QUARTER OF THE NATION---IN TIME
FOR THE PEAK CHRISTMAS TRAVEL `WINDOW`? THE SHORT ANSWER IS---YES.
DO THE 17/00Z DETERMINISTIC SOLUTIONS HAVE ALL THE `MORPHOLOGY`
DETAILS "DOWN PAT"---THE ANSWER IS NO. THE `NO` PART OF THE ANSWER
IS ON THE WINTER WEATHER SIDE--AND WHO MAY/MAY NOT SEE A `WHITE
CHRISTMAS` MORNING.

WHAT CAN BE GLEANED FROM THE 17/00Z GUIDANCE IS...THERE WILL BE A
DYNAMIC UPPER-LEVEL TROUGH EMERGING AND THE THREAT OF ORGANIZED
SYNOPTIC-SCALE PRECIPITATION ASSOCIATED WITH THE SURFACE
CYCLONE--WITH A DISTINCT WINTER SIDE---ALONG ITS NORTHERN
PERIPHERY---AND WET SIDE AHEAD OF THE DEEPER---COLD AIRMASS THAT
IS RAIN.

...MODEL PREFERENCES...
THE 17/00Z GEFS/ECENS AND THEIR DETERMINISTIC RUNS WERE IN DECENT
AGREEMENT THROUGH 22/12Z...AND WPC LIKES THE SLIGHTLY SLOWER ECENS
VERSUS THE GEFS AFTER DAY 5 FROM THE DATELINE TO THE EASTERN
SEABOARD.  VOJTESAK

...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.

FRACASSO

$$







000
FXCA20 KWBC 171916
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
215 PM EST WED DEC 17 2014

DISCUSSION FROM DECEMBER 17/00UTC: AT 500 HPA...MID LEVEL RIDGE IS
TO RAPIDLY STRENGTHEN ITS FOOTHOLD ACROSS THE CENTRAL/EASTERN
CARIBBEAN WHILE BUILDING FROM WEST-TO-EAST ACROSS THE BASIN. RIDGE
IS TO ORIGINATE OVER SOUTHERN MEXICO/NORTHERN CENTRAL
AMERICA...AND THROUGH THURSDAY MORNING IT IS TO AMPLIFY ACROSS THE
CARIBBEAN BASIN TO NORTHERN SOUTH AMERICA. THIS IS TO THEN BECOME
DOMINANT SYNOPTIC SCALE FEATURE OVER THE CARIBBEAN THROUGH THE
MEDIUM RANGE PERIOD. AS IT BUILDS...RIDGE IS TO STRENGTHEN TRADE
WINDS CAP...LEADING TO RAPID EROSION OF AVAILABLE WATER. DRYING
TREND IS TO START OVER THE NORTHERN CARIBBEAN EARLY IN THE
CYCLE...AND IT IS TO RAPIDLY EXPAND INTO THE SOUTHERN CARIBBEAN TO
NORTHERN SOUTH AMERICA. THE RIDGE ALOFT IS TO REFLECT QUITE WELL
AT LOW LEVELS OF THE ATMOSPHERE. EARLY IN THE PERIOD IT IS TO
LIMIT TO THE GULF OF MEXICO-BAHAMAS...BUT THROUGH FRIDAY MORNING
IT IS TO MIGRATE EAST INTO THE WESTERN ATLANTIC. ACROSS THE
NORTHERN CARIBBEAN ISLES THIS IS TO GENERALLY FAVOR FAIR WEATHER
CONDITIONS OVER THE NEXT FEW DAYS.

ACROSS THE BASIN...THE LOW LEVEL RIDGE IS TO SUSTAIN BRISK
EASTERLY WINDS THAT ARE TO CONVERGE ALONG A SHEAR LINE OVER THE
CENTRAL/SOUTHERN CARIBBEAN. THROUGH THURSDAY EVENING THE SHEAR
LINE IS TO BECOME ILL DEFINED. MEANWHILE...THIS IS TO ENHANCE
MOISTURE CONVERGENCE ACROSS JAMAICA TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM. THROUGH THURSDAY EVENING EXPECTING
RAPID EROSION OF AVAILABLE WATER AS THE TRADE WINDS CAP
STRENGTHENS ACROSS THE BASIN. OVER COSTA RICA/EASTERN NICARAGUA
THIS IS TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM THROUGH THURSDAY MORNING. ON THURSDAY TO FRIDAY MOST
ACTIVE IS TO CONVERGE ACROSS EASTERN NICARAGUA/NORTHEAST HONDURAS
WITH ACCUMULATION OF 05-10MM/DAY AND WIDELY ISOLATED MAXIMA OF
15MM.

AS THE MID LEVEL RIDGE HOLDS OVER THE CARIBBEAN BASIN...SHORT WAVE
PERTURBATIONS ARE TO STREAM TO THE NORTH...WITH A FAIRLY STRONG
SHORT WAVE TROUGH TO MOVE ACROSS NORTHERN MEXICO TO TEXAS LATER ON
THURSDAY. THIS CONTINUES TO THE CENTRAL USA LATER ON FRIDAY. AS IT
ENTERS NORTHWEST MEXICO THIS IS TO ENHANCE MOISTURE TRANSPORT
ACROSS NORTHERN PORTIONS OF BAJA CALIFORNIA-NORTHERN
SONORA/CHIHUAHUA...WHERE WE EXPECT RAINFALL AMOUNTS OF 00-05MM/DAY
AND MAXIMA OF 10MM. AS IT ENTERS THE CENTRAL USA THIS IS TO THEN
TRIGGER CYCLOGENESIS EARLY ON FRIDAY...WITH ASSOCIATED FRONT TO
MOVE SOUTH ACROSS THE RIO BRAVO TO THE NORTHEAST STATES OF MEXICO
LATER IN THE DAY. THROUGH SATURDAY MORNING THE FRONT IS TO
CONTINUE INTO THE NORTHWEST GULF-TAMAULIPAS MEXICO...WHERE IT IS
TO MEANDER THROUGH SATURDAY EVENING. ACROSS NORTHEAST MEXICO THIS
IS TO THEN FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF
10MM. FURTHERMORE...THE DEEPENING POLAR TROUGH IS TO SUSTAIN AN
INDUCED/INVERTED TROUGH ACROSS THE YUCATAN PENINSULA. THIS IS TO
ALSO ENHANCE MOISTURE CONVERGENCE ACROSS BELIZE-QUINTANA ROO IN
THE YUCATAN TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-20MM.

SOUTH OVER THE CARIBBEAN...EVOLVING MID LEVEL RIDGE PATTERN IS TO
ALSO FAVOR EROSION OF AVAILABLE WATER ACROSS SOUTHERN CENTRAL
AMERICA-NORTHERN SOUTH AMERICA. ACROSS PANAMA-COSTA RICA ACTIVITY
WANES THROUGH FRIDAY MORNING...WITH RAINFALL AMOUNTS OF
00-05MM/DAY AND MAXIMA OF 10MM IN DIURNAL CONVECTION. ITCZ
CONVERGENCE OVER COLOMBIA WILL LIMIT TO EJE CAFETERO/THE CAUCA
VALLEY...WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND ISOLATED MAXIMA
OF 15-20MM. THE ATLANTIC ITCZ...MEANWHILE...IS TO MEANDER SOUTH
ACROSS THE SOUTHERN GUIANAS TO VENEZUELA...WITH MOST ACTIVE
CONVECTION ACROSS AMAPA IN BRASIL-THE SOUTHERN GUIANAS TO AMAZONIA
IN VENEZUELA. IN THIS AREA EXPECTING RAINFALL AMOUNTS OF
00-05MM/DAY AND MAXIMA OF 10MM THROUGH FRIDAY MORNING...AND
05-10MM/DAY WITH  MAXIMA OF 15MM ON FRIDAY TO SATURDAY.

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 171916
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
215 PM EST WED DEC 17 2014

DISCUSSION FROM DECEMBER 17/00UTC: AT 500 HPA...MID LEVEL RIDGE IS
TO RAPIDLY STRENGTHEN ITS FOOTHOLD ACROSS THE CENTRAL/EASTERN
CARIBBEAN WHILE BUILDING FROM WEST-TO-EAST ACROSS THE BASIN. RIDGE
IS TO ORIGINATE OVER SOUTHERN MEXICO/NORTHERN CENTRAL
AMERICA...AND THROUGH THURSDAY MORNING IT IS TO AMPLIFY ACROSS THE
CARIBBEAN BASIN TO NORTHERN SOUTH AMERICA. THIS IS TO THEN BECOME
DOMINANT SYNOPTIC SCALE FEATURE OVER THE CARIBBEAN THROUGH THE
MEDIUM RANGE PERIOD. AS IT BUILDS...RIDGE IS TO STRENGTHEN TRADE
WINDS CAP...LEADING TO RAPID EROSION OF AVAILABLE WATER. DRYING
TREND IS TO START OVER THE NORTHERN CARIBBEAN EARLY IN THE
CYCLE...AND IT IS TO RAPIDLY EXPAND INTO THE SOUTHERN CARIBBEAN TO
NORTHERN SOUTH AMERICA. THE RIDGE ALOFT IS TO REFLECT QUITE WELL
AT LOW LEVELS OF THE ATMOSPHERE. EARLY IN THE PERIOD IT IS TO
LIMIT TO THE GULF OF MEXICO-BAHAMAS...BUT THROUGH FRIDAY MORNING
IT IS TO MIGRATE EAST INTO THE WESTERN ATLANTIC. ACROSS THE
NORTHERN CARIBBEAN ISLES THIS IS TO GENERALLY FAVOR FAIR WEATHER
CONDITIONS OVER THE NEXT FEW DAYS.

ACROSS THE BASIN...THE LOW LEVEL RIDGE IS TO SUSTAIN BRISK
EASTERLY WINDS THAT ARE TO CONVERGE ALONG A SHEAR LINE OVER THE
CENTRAL/SOUTHERN CARIBBEAN. THROUGH THURSDAY EVENING THE SHEAR
LINE IS TO BECOME ILL DEFINED. MEANWHILE...THIS IS TO ENHANCE
MOISTURE CONVERGENCE ACROSS JAMAICA TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM. THROUGH THURSDAY EVENING EXPECTING
RAPID EROSION OF AVAILABLE WATER AS THE TRADE WINDS CAP
STRENGTHENS ACROSS THE BASIN. OVER COSTA RICA/EASTERN NICARAGUA
THIS IS TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM THROUGH THURSDAY MORNING. ON THURSDAY TO FRIDAY MOST
ACTIVE IS TO CONVERGE ACROSS EASTERN NICARAGUA/NORTHEAST HONDURAS
WITH ACCUMULATION OF 05-10MM/DAY AND WIDELY ISOLATED MAXIMA OF
15MM.

AS THE MID LEVEL RIDGE HOLDS OVER THE CARIBBEAN BASIN...SHORT WAVE
PERTURBATIONS ARE TO STREAM TO THE NORTH...WITH A FAIRLY STRONG
SHORT WAVE TROUGH TO MOVE ACROSS NORTHERN MEXICO TO TEXAS LATER ON
THURSDAY. THIS CONTINUES TO THE CENTRAL USA LATER ON FRIDAY. AS IT
ENTERS NORTHWEST MEXICO THIS IS TO ENHANCE MOISTURE TRANSPORT
ACROSS NORTHERN PORTIONS OF BAJA CALIFORNIA-NORTHERN
SONORA/CHIHUAHUA...WHERE WE EXPECT RAINFALL AMOUNTS OF 00-05MM/DAY
AND MAXIMA OF 10MM. AS IT ENTERS THE CENTRAL USA THIS IS TO THEN
TRIGGER CYCLOGENESIS EARLY ON FRIDAY...WITH ASSOCIATED FRONT TO
MOVE SOUTH ACROSS THE RIO BRAVO TO THE NORTHEAST STATES OF MEXICO
LATER IN THE DAY. THROUGH SATURDAY MORNING THE FRONT IS TO
CONTINUE INTO THE NORTHWEST GULF-TAMAULIPAS MEXICO...WHERE IT IS
TO MEANDER THROUGH SATURDAY EVENING. ACROSS NORTHEAST MEXICO THIS
IS TO THEN FAVOR RAINFALL AMOUNTS OF 00-05MM/DAY AND MAXIMA OF
10MM. FURTHERMORE...THE DEEPENING POLAR TROUGH IS TO SUSTAIN AN
INDUCED/INVERTED TROUGH ACROSS THE YUCATAN PENINSULA. THIS IS TO
ALSO ENHANCE MOISTURE CONVERGENCE ACROSS BELIZE-QUINTANA ROO IN
THE YUCATAN TO SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-20MM.

SOUTH OVER THE CARIBBEAN...EVOLVING MID LEVEL RIDGE PATTERN IS TO
ALSO FAVOR EROSION OF AVAILABLE WATER ACROSS SOUTHERN CENTRAL
AMERICA-NORTHERN SOUTH AMERICA. ACROSS PANAMA-COSTA RICA ACTIVITY
WANES THROUGH FRIDAY MORNING...WITH RAINFALL AMOUNTS OF
00-05MM/DAY AND MAXIMA OF 10MM IN DIURNAL CONVECTION. ITCZ
CONVERGENCE OVER COLOMBIA WILL LIMIT TO EJE CAFETERO/THE CAUCA
VALLEY...WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND ISOLATED MAXIMA
OF 15-20MM. THE ATLANTIC ITCZ...MEANWHILE...IS TO MEANDER SOUTH
ACROSS THE SOUTHERN GUIANAS TO VENEZUELA...WITH MOST ACTIVE
CONVECTION ACROSS AMAPA IN BRASIL-THE SOUTHERN GUIANAS TO AMAZONIA
IN VENEZUELA. IN THIS AREA EXPECTING RAINFALL AMOUNTS OF
00-05MM/DAY AND MAXIMA OF 10MM THROUGH FRIDAY MORNING...AND
05-10MM/DAY WITH  MAXIMA OF 15MM ON FRIDAY TO SATURDAY.

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 171641
PMDSA

SOUTH AMERICA FORECAST DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1140 AM EST WED DEC 17 2014

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

MODEL DISCUSSION (VALID FROM DECEMBER 17 AT 00UTC): GLOBAL MODELS
CONTINUE TO AGREE ON PATTERN EVOLUTION ACROSS THE SOUTH AMERICAN
DOMAIN...FOLLOWING SIMILAR EVOLUTION THROUGH 132-144 HRS.
CONFIDENCE IN THE FORECAST IS HIGH.

AT MID LEVELS...SHORT WAVE TROUGH ON THE NORTHERN STREAM MOVES
ACROSS ARGENTINA-URUGUAY EARLY IN THE CYCLE...AND OFF THE COAST
INTO THE WESTERN ATLANTIC LATER THIS EVENING. TROUGH IS TO THEN
MEANDER EAST ACROSS 45W BY 48 HRS...NEARING 30W BY 96 HRS. AS IT
PULLS ACROSS THE CONTINENT...A SUBTROPICAL JET MAXIMA IS TO
ACCOMPANY THIS TROUGH. IN A PERPENDICULAR FLOW TO THE NORTHERN
ANDES OF CHILE THIS IS TO FAVOR GENERATION OF LEESIDE
PERTURBATIONS ACROSS MID SECTIONS OF SOUTH AMERICA. AT LOW
LEVELS...UPPER LEVEL JET AND MID LEVEL TROUGH ARE TO INTERACT WITH
A SURFACE TROUGH OVER PARAGUAY/SOUTHERN BRASIL...TRIGGERING
MODERATE TO HEAVY CONVECTION EARLY IN THE CYCLE. THROUGH 36 HRS
THIS IS TO PEAK AT 20-45MM. BUT AS THE MID LEVEL TROUGH MOVES AWAY
AND JET STARTS TO WEAKEN THIS DECREASES TO 15-25MM BY 48-60 HRS.

AMPLIFYING MID/UPPER LEVEL RIDGE OVER THE EASTERN SOUTH PACIFIC IS
TO THEN FAVOR RAPID EVOLUTION TO A LONG WAVE/HIGH AMPLITUDE
PATTERN ACROSS THE SOUTH AMERICAN DOMAIN. RIDGE IS TO BUILD
UPSTREAM ALONG 100W/110W TO THE POLAR ICE CAP.
THIS...IN-TURN...DIVERTS SHORT WAVE ENERGY NORTHWARD ACROSS THE
BELLINGSHAUSEN SEA TO THE SOUTHERN CONE. INFLOW OF SHORT WAVE
ENERGY WILL THEN FEED A TROUGH TO THE EAST. THE LATTER IS TO ENTER
SOUTHERN CHILE BY 48 HRS...THEN SLOWLY MEANDERS EAST WHILE RAPIDLY
AMPLIFYING NORTH ACROSS CHILE AND ARGENTINA. THROUGH 72 HRS THE
TROUGH IS TO NEAR 35S...AND BY 96-108 HRS IT ENTERS THE NORTHERN
PROVINCES IN ARGENTINA-SOUTHEAST PARAGUAY. EARLY IN THE CYCLE THIS
IS TO SUSTAIN AN ELONGATED FRONT ACROSS THE SOUTH PACIFIC INTO
SOUTHERN PORTIONS OF CHILE AND ARGENTINA. THE DEEP TROUGH PATTERN
IS TO FAVOR ADVECTION OF SUBTROPICAL MOISTURE INTO SOUTHERN
PORTIONS OF CHILE. AS A RESULT...EXPECTING ORGANIZED CONVECTION
BETWEEN ISLA DE CHILOE AND PUNTA ARENAS IN SOUTHERN CHILE OVER THE
NEXT TWO DAYS...WITH DAILY MAXIMA IN THIS AREA OF 20-40MM. BUT AS
THE TROUGH DEEPENS AND COLD AIR ADVECTS ACROSS THE DRAKE PASSAGE
MODELS SHOWING RISK OF SNOW/RAIN SHOWERS AFFECTING TIERRA DEL
FUEGO AND THE SOUTHERN ANDES. FURTHERMORE...THE DEEPENING TROUGH
WILL DRIVE THE FRONT NORTH ACROSS PATAGONIA/CENTRAL PORTIONS OF
CHILE BY 72 HRS. A PAMPERO JET IS TO THEN FORCE THIS BOUNDARY
FARTHER NORTH INTO URUGUAY-NORTHERN ARGENTINA BY 96 HRS...AND
ACROSS SOUTHERN BRASIL-PARAGUAY BY 120 HRS. AS THE FRONT SURGES
ACROSS ARGENTINA IT IS TO TRIGGER A SQUALL LINE AND SEVERE
CONVECTION ACROSS URUGUAY-SOUTHERN BRASIL-NORTHERN PROVINCES IN
ARGENTINA AND PORTIONS OF PARAGUAY...WITH RAINFALL AMOUNTS OF
50-100MM. BY 120-132 HRS THE FOCUS OF THE HEAVY CONVECTION SHIFTS
TO EASTERN/NORTHERN BOLIVIA-RONDONIA/MATO GROSSO IN BRASIL...WITH
RAINFALL MAXIMA OF 40-80MM.

AT 200 HPA...A RIDGE TO THE NORTH OF 30S IS TO REMAIN DOMINANT
SYNOPTIC SCALE FEATURE DURING THE NEXT FEW DAYS...WITH AXIS TO
CENTER ON A CLOSED HIGH THAT MEANDERS BETWEEN BOLIVIA AND MATO
GROSSO IN BRASIL. A TROUGH LIES TO THE EAST OF THIS RIDGE...WITH
AXIS NORTH ALONG THE NORTHEAST COAST OF BRASIL TO THE TROPICAL
ATLANTIC. AN AREA OF DIVERGENCE ALOFT IS TO DEVELOP BETWEEN THIS
TROUGH AND THE RIDGE TO THE WEST. THIS IS TO VENT DEEP CONVECTION
ACROSS NORTHEAST AND CENTRAL STATES OF BRASIL...TO SUSTAIN
SCATTERED CONVECTION WITH DAILY MAXIMA OF 20-40MM. LOCALLY HIGHER
AMOUNTS ARE HIGHLY LIKELY. FURTHERMORE...THE RIDGE ALOFT IS TO
ALSO FAVOR ORGANIZED CONVECTION ACROSS CENTRAL-SOUTHERN JUNGLE OF
PERU-CENTRAL BOLIVIA OVER THE NEXT COUPLE OF DAYS...WITH MAXIMA OF
20-45MM. BUT AS POLAR TROUGH DEEPENS TO THE SOUTH THIS WILL
DECREASE TO 15-25MM.

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

$$






000
FXUS02 KWBC 171600
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1100 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...

..OVERVIEW...
ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A NEGATIVELY-TILTED TROUGH SETTING UP
OVER THE GREAT LAKES AND MID-ATLANTIC/NORTHEAST REGION(S) AROUND
THE CHRISTMAS EVE TIME FRAME.

A `BUCKLING` IN THE PERSISTENTLY-STRONG WESTERLY PACIFIC JET WILL
LIKELY OCCUR DURING WEEKEND---AND BECOME THE IMPETUS FOR
CHANGE---AMPLIFYING THE PATTERN DOWNSTREAM OVER THE LOWER 48. THE
17/00Z GEFS/ECENS MEANS HAVE WAVERED ON THE SMALLER-SCALE DETAILS
SURROUNDING THE PATTERN DOWNSTREAM OF THE ROCKIES...BUT GENERALLY
AGREE THAT A 500MB WAVE FORMS INVOF THE CENTRAL MIDWEST---WITH
PACIFIC JET SUPPORT CARVING OUT THE 200MB-500MB TROUGH TOWARDS THE
END OF THIS MEDIUM RANGE PERIOD.

...UNCERTAINTY ASSESSMENT...
AFOREMENTIONED `BUCKLING` OF THE PACIFIC JET ---IN THE OVERVIEW---
ALONG THE WEST COAST ON SAT/SUN APPEARED TO BE THE LEADING EDGE OF
A BROAD WARM FRONT THAT SURGES QUICKLY THROUGH THE NORTHERN
CONTINENTAL DIVIDE AND NORTHERN HIGH PLAINS. ON MONDAY...THE
FAST-MOVING NORTHWEST FLOW---NOSE OF THIS PACIFIC JET
CONFIGURATION ALOFT--SUPPORTS THE DEEPENING OF LEE SIDE
CYCLOGENESIS OVER SOUTHEASTERN ALBERTA AND THE BIRTH OF A
WELL-DEFINED SURFACE CYCLONE---MIGRATING ACROSS THE UPPER HALF OF
THE MISSOURI VALLEY EARLY IN THE PERIOD. ITS `MORPHOLOGY` AROUND
DAY 6...IN THE MIDWEST---APPEARS TO BE A FUNCTION OF ITS DEPTH AND
FORWARD MOTION IN RELATIONSHIP TO THE UPPER-LEVEL JET. ONE OF THE
SMALLER-SCALE DETAILS IS---CAN THE SURFACE CYCLONE DRAW UPON
ENOUGH COLDER...CANADIAN AIR AND PULL THAT COLDER AIRMASS
SOUTHEASTWARD FASTER ENOUGH---TO INTENSIFY AND AMPLIFY---THE
ENTIRE PATTERN IN THE NORTHEAST QUARTER OF THE NATION---IN TIME
FOR THE PEAK CHRISTMAS TRAVEL `WINDOW`. THE SHORT ANSWER IS---YES.
DO THE 17/00Z DETERMINISTIC SOLUTIONS HAVE ALL THE `MORPHOLOGY`
DETAILS "DOWN PAT"---THE ANSWER IS NO. THE `NO` PART OF THE ANSWER
IS ON THE WINTER WEATHER SIDE--AND WHO MAY/MAY NOT SEE A `WHITE
CHRISTMAS` MORNING.

WHAT CAN BE GLEANED FROM THE 17/00Z GUIDANCE IS...THERE WILL BE A
DYNAMIC UPPER-LEVEL TROUGH EMERGING AND THE THREAT OF ORGANIZED
SYNOPTIC-SCALE PRECIPITATION ASSOCIATED WITH THE SURFACE
CYCLONE--WITH A DISTINCT WINTER SIDE---ALONG ITS NORTHERN
PERIPHERY---AND WET SIDE AHEAD OF THE DEEPER---COLD AIRMASS THAT
IS RAIN.

...MODEL PREFERENCES...
THE 17/00Z GEFS/ECENS AND THEIR DETERMINISTIC RUNS WERE IN DECENT
AGREEMENT THROUGH 22/12Z...AND WPC LIKES THE SLIGHTLY SLOWER ECENS
VERSUS THE GEFS AFTER DAY 5 FROM THE DATELINE TO THE EASTERN
SEABOARD.  VOJTESAK

...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.


FRACASSO

$$






000
FXUS02 KWBC 171600
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1100 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...

..OVERVIEW...
ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A NEGATIVELY-TILTED TROUGH SETTING UP
OVER THE GREAT LAKES AND MID-ATLANTIC/NORTHEAST REGION(S) AROUND
THE CHRISTMAS EVE TIME FRAME.

A `BUCKLING` IN THE PERSISTENTLY-STRONG WESTERLY PACIFIC JET WILL
LIKELY OCCUR DURING WEEKEND---AND BECOME THE IMPETUS FOR
CHANGE---AMPLIFYING THE PATTERN DOWNSTREAM OVER THE LOWER 48. THE
17/00Z GEFS/ECENS MEANS HAVE WAVERED ON THE SMALLER-SCALE DETAILS
SURROUNDING THE PATTERN DOWNSTREAM OF THE ROCKIES...BUT GENERALLY
AGREE THAT A 500MB WAVE FORMS INVOF THE CENTRAL MIDWEST---WITH
PACIFIC JET SUPPORT CARVING OUT THE 200MB-500MB TROUGH TOWARDS THE
END OF THIS MEDIUM RANGE PERIOD.

...UNCERTAINTY ASSESSMENT...
AFOREMENTIONED `BUCKLING` OF THE PACIFIC JET ---IN THE OVERVIEW---
ALONG THE WEST COAST ON SAT/SUN APPEARED TO BE THE LEADING EDGE OF
A BROAD WARM FRONT THAT SURGES QUICKLY THROUGH THE NORTHERN
CONTINENTAL DIVIDE AND NORTHERN HIGH PLAINS. ON MONDAY...THE
FAST-MOVING NORTHWEST FLOW---NOSE OF THIS PACIFIC JET
CONFIGURATION ALOFT--SUPPORTS THE DEEPENING OF LEE SIDE
CYCLOGENESIS OVER SOUTHEASTERN ALBERTA AND THE BIRTH OF A
WELL-DEFINED SURFACE CYCLONE---MIGRATING ACROSS THE UPPER HALF OF
THE MISSOURI VALLEY EARLY IN THE PERIOD. ITS `MORPHOLOGY` AROUND
DAY 6...IN THE MIDWEST---APPEARS TO BE A FUNCTION OF ITS DEPTH AND
FORWARD MOTION IN RELATIONSHIP TO THE UPPER-LEVEL JET. ONE OF THE
SMALLER-SCALE DETAILS IS---CAN THE SURFACE CYCLONE DRAW UPON
ENOUGH COLDER...CANADIAN AIR AND PULL THAT COLDER AIRMASS
SOUTHEASTWARD FASTER ENOUGH---TO INTENSIFY AND AMPLIFY---THE
ENTIRE PATTERN IN THE NORTHEAST QUARTER OF THE NATION---IN TIME
FOR THE PEAK CHRISTMAS TRAVEL `WINDOW`. THE SHORT ANSWER IS---YES.
DO THE 17/00Z DETERMINISTIC SOLUTIONS HAVE ALL THE `MORPHOLOGY`
DETAILS "DOWN PAT"---THE ANSWER IS NO. THE `NO` PART OF THE ANSWER
IS ON THE WINTER WEATHER SIDE--AND WHO MAY/MAY NOT SEE A `WHITE
CHRISTMAS` MORNING.

WHAT CAN BE GLEANED FROM THE 17/00Z GUIDANCE IS...THERE WILL BE A
DYNAMIC UPPER-LEVEL TROUGH EMERGING AND THE THREAT OF ORGANIZED
SYNOPTIC-SCALE PRECIPITATION ASSOCIATED WITH THE SURFACE
CYCLONE--WITH A DISTINCT WINTER SIDE---ALONG ITS NORTHERN
PERIPHERY---AND WET SIDE AHEAD OF THE DEEPER---COLD AIRMASS THAT
IS RAIN.

...MODEL PREFERENCES...
THE 17/00Z GEFS/ECENS AND THEIR DETERMINISTIC RUNS WERE IN DECENT
AGREEMENT THROUGH 22/12Z...AND WPC LIKES THE SLIGHTLY SLOWER ECENS
VERSUS THE GEFS AFTER DAY 5 FROM THE DATELINE TO THE EASTERN
SEABOARD.  VOJTESAK

...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.


FRACASSO

$$







000
FXUS02 KWBC 171600
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1100 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...

..OVERVIEW...
ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A NEGATIVELY-TILTED TROUGH SETTING UP
OVER THE GREAT LAKES AND MID-ATLANTIC/NORTHEAST REGION(S) AROUND
THE CHRISTMAS EVE TIME FRAME.

A `BUCKLING` IN THE PERSISTENTLY-STRONG WESTERLY PACIFIC JET WILL
LIKELY OCCUR DURING WEEKEND---AND BECOME THE IMPETUS FOR
CHANGE---AMPLIFYING THE PATTERN DOWNSTREAM OVER THE LOWER 48. THE
17/00Z GEFS/ECENS MEANS HAVE WAVERED ON THE SMALLER-SCALE DETAILS
SURROUNDING THE PATTERN DOWNSTREAM OF THE ROCKIES...BUT GENERALLY
AGREE THAT A 500MB WAVE FORMS INVOF THE CENTRAL MIDWEST---WITH
PACIFIC JET SUPPORT CARVING OUT THE 200MB-500MB TROUGH TOWARDS THE
END OF THIS MEDIUM RANGE PERIOD.

...UNCERTAINTY ASSESSMENT...
AFOREMENTIONED `BUCKLING` OF THE PACIFIC JET ---IN THE OVERVIEW---
ALONG THE WEST COAST ON SAT/SUN APPEARED TO BE THE LEADING EDGE OF
A BROAD WARM FRONT THAT SURGES QUICKLY THROUGH THE NORTHERN
CONTINENTAL DIVIDE AND NORTHERN HIGH PLAINS. ON MONDAY...THE
FAST-MOVING NORTHWEST FLOW---NOSE OF THIS PACIFIC JET
CONFIGURATION ALOFT--SUPPORTS THE DEEPENING OF LEE SIDE
CYCLOGENESIS OVER SOUTHEASTERN ALBERTA AND THE BIRTH OF A
WELL-DEFINED SURFACE CYCLONE---MIGRATING ACROSS THE UPPER HALF OF
THE MISSOURI VALLEY EARLY IN THE PERIOD. ITS `MORPHOLOGY` AROUND
DAY 6...IN THE MIDWEST---APPEARS TO BE A FUNCTION OF ITS DEPTH AND
FORWARD MOTION IN RELATIONSHIP TO THE UPPER-LEVEL JET. ONE OF THE
SMALLER-SCALE DETAILS IS---CAN THE SURFACE CYCLONE DRAW UPON
ENOUGH COLDER...CANADIAN AIR AND PULL THAT COLDER AIRMASS
SOUTHEASTWARD FASTER ENOUGH---TO INTENSIFY AND AMPLIFY---THE
ENTIRE PATTERN IN THE NORTHEAST QUARTER OF THE NATION---IN TIME
FOR THE PEAK CHRISTMAS TRAVEL `WINDOW`. THE SHORT ANSWER IS---YES.
DO THE 17/00Z DETERMINISTIC SOLUTIONS HAVE ALL THE `MORPHOLOGY`
DETAILS "DOWN PAT"---THE ANSWER IS NO. THE `NO` PART OF THE ANSWER
IS ON THE WINTER WEATHER SIDE--AND WHO MAY/MAY NOT SEE A `WHITE
CHRISTMAS` MORNING.

WHAT CAN BE GLEANED FROM THE 17/00Z GUIDANCE IS...THERE WILL BE A
DYNAMIC UPPER-LEVEL TROUGH EMERGING AND THE THREAT OF ORGANIZED
SYNOPTIC-SCALE PRECIPITATION ASSOCIATED WITH THE SURFACE
CYCLONE--WITH A DISTINCT WINTER SIDE---ALONG ITS NORTHERN
PERIPHERY---AND WET SIDE AHEAD OF THE DEEPER---COLD AIRMASS THAT
IS RAIN.

...MODEL PREFERENCES...
THE 17/00Z GEFS/ECENS AND THEIR DETERMINISTIC RUNS WERE IN DECENT
AGREEMENT THROUGH 22/12Z...AND WPC LIKES THE SLIGHTLY SLOWER ECENS
VERSUS THE GEFS AFTER DAY 5 FROM THE DATELINE TO THE EASTERN
SEABOARD.  VOJTESAK

...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.


FRACASSO

$$






000
FXUS02 KWBC 171600
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1100 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...

..OVERVIEW...
ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A NEGATIVELY-TILTED TROUGH SETTING UP
OVER THE GREAT LAKES AND MID-ATLANTIC/NORTHEAST REGION(S) AROUND
THE CHRISTMAS EVE TIME FRAME.

A `BUCKLING` IN THE PERSISTENTLY-STRONG WESTERLY PACIFIC JET WILL
LIKELY OCCUR DURING WEEKEND---AND BECOME THE IMPETUS FOR
CHANGE---AMPLIFYING THE PATTERN DOWNSTREAM OVER THE LOWER 48. THE
17/00Z GEFS/ECENS MEANS HAVE WAVERED ON THE SMALLER-SCALE DETAILS
SURROUNDING THE PATTERN DOWNSTREAM OF THE ROCKIES...BUT GENERALLY
AGREE THAT A 500MB WAVE FORMS INVOF THE CENTRAL MIDWEST---WITH
PACIFIC JET SUPPORT CARVING OUT THE 200MB-500MB TROUGH TOWARDS THE
END OF THIS MEDIUM RANGE PERIOD.

...UNCERTAINTY ASSESSMENT...
AFOREMENTIONED `BUCKLING` OF THE PACIFIC JET ---IN THE OVERVIEW---
ALONG THE WEST COAST ON SAT/SUN APPEARED TO BE THE LEADING EDGE OF
A BROAD WARM FRONT THAT SURGES QUICKLY THROUGH THE NORTHERN
CONTINENTAL DIVIDE AND NORTHERN HIGH PLAINS. ON MONDAY...THE
FAST-MOVING NORTHWEST FLOW---NOSE OF THIS PACIFIC JET
CONFIGURATION ALOFT--SUPPORTS THE DEEPENING OF LEE SIDE
CYCLOGENESIS OVER SOUTHEASTERN ALBERTA AND THE BIRTH OF A
WELL-DEFINED SURFACE CYCLONE---MIGRATING ACROSS THE UPPER HALF OF
THE MISSOURI VALLEY EARLY IN THE PERIOD. ITS `MORPHOLOGY` AROUND
DAY 6...IN THE MIDWEST---APPEARS TO BE A FUNCTION OF ITS DEPTH AND
FORWARD MOTION IN RELATIONSHIP TO THE UPPER-LEVEL JET. ONE OF THE
SMALLER-SCALE DETAILS IS---CAN THE SURFACE CYCLONE DRAW UPON
ENOUGH COLDER...CANADIAN AIR AND PULL THAT COLDER AIRMASS
SOUTHEASTWARD FASTER ENOUGH---TO INTENSIFY AND AMPLIFY---THE
ENTIRE PATTERN IN THE NORTHEAST QUARTER OF THE NATION---IN TIME
FOR THE PEAK CHRISTMAS TRAVEL `WINDOW`. THE SHORT ANSWER IS---YES.
DO THE 17/00Z DETERMINISTIC SOLUTIONS HAVE ALL THE `MORPHOLOGY`
DETAILS "DOWN PAT"---THE ANSWER IS NO. THE `NO` PART OF THE ANSWER
IS ON THE WINTER WEATHER SIDE--AND WHO MAY/MAY NOT SEE A `WHITE
CHRISTMAS` MORNING.

WHAT CAN BE GLEANED FROM THE 17/00Z GUIDANCE IS...THERE WILL BE A
DYNAMIC UPPER-LEVEL TROUGH EMERGING AND THE THREAT OF ORGANIZED
SYNOPTIC-SCALE PRECIPITATION ASSOCIATED WITH THE SURFACE
CYCLONE--WITH A DISTINCT WINTER SIDE---ALONG ITS NORTHERN
PERIPHERY---AND WET SIDE AHEAD OF THE DEEPER---COLD AIRMASS THAT
IS RAIN.

...MODEL PREFERENCES...
THE 17/00Z GEFS/ECENS AND THEIR DETERMINISTIC RUNS WERE IN DECENT
AGREEMENT THROUGH 22/12Z...AND WPC LIKES THE SLIGHTLY SLOWER ECENS
VERSUS THE GEFS AFTER DAY 5 FROM THE DATELINE TO THE EASTERN
SEABOARD.  VOJTESAK

...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.


FRACASSO

$$







000
FXSA20 KWBC 171427
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
926 AM EST WED DEC 17 2014

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

SYNOPSIS (VALID FROM DECEMBER 17 AT 00UTC): THE 200 HPA ANALYSIS
SHOWS A BROAD CELL OF THE SUBTROPICAL RIDGE ENVELOPING CONTINENTAL
AREA TO THE NORTH OF 30S. THE RIDGE ANCHORS ON A CLOSED HIGH NEAR
LAKE TITICACA. THE RIDGE ALOFT IS VENTING DEEP CONVECTION ACROSS
CENTRAL STATES OF BRASIL-ALTIPLANO OF BOLIVIA AND THE SIERRA OF
PERU. A TROUGH TO THE EAST EXTENDS BETWEEN 40W-20W. THIS IS
FOCUSING SHORT WAVE ENERGY ACROSS BAHIA-PIAUI-CEARA...WHERE IT
FAVORS SCATTERED DEEP CONVECTION.

THE JET ANALYSIS AT 250 HPA SHOWS THE SOUTHERN POLAR WITH AXIS
ALONG A 158KT MAXIMUM AT 48S 129W...A 153KT MAXIMUM AT 52S
117W...A 137KT MAXIMUM AT 54S 100W...EXITING AT 49S 74W. THE
NORTHERN POLAR LIES ALONG A 142KT MAXIMUM AT 46S 125W...50S
102W...EXITING AT 46S 85W. THE SUBTROPICAL JET HAS ITS ENTRANCE AT
25S 89W...ALONG 27S 71W...URUGUAY...EXITING AT 36S 45W. THE JET
HAS A FINGER TO THE NORTH THAT EXTENDS BETWEEN 29S 38W AND 20S 39W.

AT 500 HPA...A RIDGE OVER THE PACIFIC EXTENDS BETWEEN 125W-95W TO
50S...WHILE CENTERING ON A CLOSED HIGH NEAR 33S 115W. THIS
SUSTAINS A TIGHT GRADIENT TO THE SOUTH OF 45S...WITH TIGHT BELT OF
MID LATITUDE WESTERLIES DOMINATING THE EASTERN SOUTH
PACIFIC-SOUTHERN CONE OF SOUTH AMERICA. SHORT WAVE PERTURBATIONS
EMBED IN THIS FLOW...STREAMING INTO SOUTHERN PORTIONS OF
CHILE/TIERRA DEL FUEGO. IN THIS FLOW...A FAIRLY STRONG SHORT WAVE
PERTURBATION IS MOVING ACROSS THE ANTARCTIC PENINSULA TO THE
WEDDELL SEA. A SHORT WAVE TROUGH ON THE NORTHERN STREAM
FOLLOWS...WITH AXIS NEARING CENTRAL REGIONS OF CHILE. THIS IF
FOCUSING THE SUBTROPICAL JET ACROSS NORTHERN
CHILE/ARGENTINA...FAVORING GENERATION OF LEE SIDE PERTURBATIONS
ACROSS THE NORTHERN PROVINCES-SOUTHERN PARAGUAY/ SOUTHERN BRASIL.
THIS...IN-TURN...PROVIDES DYNAMICAL SUPPORT TO AN MCS OVER
SOUTHEAST PARAGUAY-MESOPOTAMIA VALLEY IN ARGENTINA.

AT LOW LEVELS...A RIDGE ON THE NORTHERN STREAM LIES OVER THE
EASTERN PACIFIC...ANCHORING ON TWO 1029 HPA HIGHS...WITH THE
WESTERNMOST CENTERING NEAR 34S 109W AND THE EASTERNMOST AT 39S
95W. AN ELONGATED FRONT LIES TO THE SOUTH...EXTENDING ALONG A 996
HPA LOW AT 55S 65W...SOUTHERN PATAGONIA...46S 71W...47S 76W...A
1000 HPA LOW AT 54S 95W...50S 100W...AND 49S 109W. ANOTHER FRONT
EXTENDS FROM AN OCCLUDED 974 HPA LOW AT 61S 46W...A 982 HPA LOW AT
61S 38W...55S 34W...A 996 HPA LOW AT 54S 39W...49S 42W...47S
47W...A 1010 HPA LOW AT 46S 54W... NORTHERN PATAGONIA...TEMUCO
CHILE...TO A 1022 HPA LOW AT 37S 78W. A RIDGE OVER THE ATLANTIC
CENTERS ON A 1029 HPA HIGH AT 40S 33W. AN ELONGATED FRONT TO THE
NORTH LIES ALONG 36S 14W...32S 28W...A 1012 HPA LOW AT 29S
37W...26S 40W...TO RIO GRANDE DO SUL.

ARREAGA...INAMHI (ECUADOR)
DURAN...SENAMHI (PERU)
DAVISON...WPC (USA)
$$







000
FXSA20 KWBC 171427
PMDSA

SOUTH AMERICA SYNOPTIC DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
926 AM EST WED DEC 17 2014

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

SYNOPSIS (VALID FROM DECEMBER 17 AT 00UTC): THE 200 HPA ANALYSIS
SHOWS A BROAD CELL OF THE SUBTROPICAL RIDGE ENVELOPING CONTINENTAL
AREA TO THE NORTH OF 30S. THE RIDGE ANCHORS ON A CLOSED HIGH NEAR
LAKE TITICACA. THE RIDGE ALOFT IS VENTING DEEP CONVECTION ACROSS
CENTRAL STATES OF BRASIL-ALTIPLANO OF BOLIVIA AND THE SIERRA OF
PERU. A TROUGH TO THE EAST EXTENDS BETWEEN 40W-20W. THIS IS
FOCUSING SHORT WAVE ENERGY ACROSS BAHIA-PIAUI-CEARA...WHERE IT
FAVORS SCATTERED DEEP CONVECTION.

THE JET ANALYSIS AT 250 HPA SHOWS THE SOUTHERN POLAR WITH AXIS
ALONG A 158KT MAXIMUM AT 48S 129W...A 153KT MAXIMUM AT 52S
117W...A 137KT MAXIMUM AT 54S 100W...EXITING AT 49S 74W. THE
NORTHERN POLAR LIES ALONG A 142KT MAXIMUM AT 46S 125W...50S
102W...EXITING AT 46S 85W. THE SUBTROPICAL JET HAS ITS ENTRANCE AT
25S 89W...ALONG 27S 71W...URUGUAY...EXITING AT 36S 45W. THE JET
HAS A FINGER TO THE NORTH THAT EXTENDS BETWEEN 29S 38W AND 20S 39W.

AT 500 HPA...A RIDGE OVER THE PACIFIC EXTENDS BETWEEN 125W-95W TO
50S...WHILE CENTERING ON A CLOSED HIGH NEAR 33S 115W. THIS
SUSTAINS A TIGHT GRADIENT TO THE SOUTH OF 45S...WITH TIGHT BELT OF
MID LATITUDE WESTERLIES DOMINATING THE EASTERN SOUTH
PACIFIC-SOUTHERN CONE OF SOUTH AMERICA. SHORT WAVE PERTURBATIONS
EMBED IN THIS FLOW...STREAMING INTO SOUTHERN PORTIONS OF
CHILE/TIERRA DEL FUEGO. IN THIS FLOW...A FAIRLY STRONG SHORT WAVE
PERTURBATION IS MOVING ACROSS THE ANTARCTIC PENINSULA TO THE
WEDDELL SEA. A SHORT WAVE TROUGH ON THE NORTHERN STREAM
FOLLOWS...WITH AXIS NEARING CENTRAL REGIONS OF CHILE. THIS IF
FOCUSING THE SUBTROPICAL JET ACROSS NORTHERN
CHILE/ARGENTINA...FAVORING GENERATION OF LEE SIDE PERTURBATIONS
ACROSS THE NORTHERN PROVINCES-SOUTHERN PARAGUAY/ SOUTHERN BRASIL.
THIS...IN-TURN...PROVIDES DYNAMICAL SUPPORT TO AN MCS OVER
SOUTHEAST PARAGUAY-MESOPOTAMIA VALLEY IN ARGENTINA.

AT LOW LEVELS...A RIDGE ON THE NORTHERN STREAM LIES OVER THE
EASTERN PACIFIC...ANCHORING ON TWO 1029 HPA HIGHS...WITH THE
WESTERNMOST CENTERING NEAR 34S 109W AND THE EASTERNMOST AT 39S
95W. AN ELONGATED FRONT LIES TO THE SOUTH...EXTENDING ALONG A 996
HPA LOW AT 55S 65W...SOUTHERN PATAGONIA...46S 71W...47S 76W...A
1000 HPA LOW AT 54S 95W...50S 100W...AND 49S 109W. ANOTHER FRONT
EXTENDS FROM AN OCCLUDED 974 HPA LOW AT 61S 46W...A 982 HPA LOW AT
61S 38W...55S 34W...A 996 HPA LOW AT 54S 39W...49S 42W...47S
47W...A 1010 HPA LOW AT 46S 54W... NORTHERN PATAGONIA...TEMUCO
CHILE...TO A 1022 HPA LOW AT 37S 78W. A RIDGE OVER THE ATLANTIC
CENTERS ON A 1029 HPA HIGH AT 40S 33W. AN ELONGATED FRONT TO THE
NORTH LIES ALONG 36S 14W...32S 28W...A 1012 HPA LOW AT 29S
37W...26S 40W...TO RIO GRANDE DO SUL.

ARREAGA...INAMHI (ECUADOR)
DURAN...SENAMHI (PERU)
DAVISON...WPC (USA)
$$






000
FXCA20 KWBC 171137
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
636 AM EST WED DEC 17 2014

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI. BUILDING MID
LEVEL RIDGE IS TO RAPIDLY STRENGTHEN ITS FOOTHOLD ACROSS THE
CENTRAL/EASTERN CARIBBEAN. THIS IS TO THEN BECOME DOMINANT
SYNOPTIC SCALE FEATURE THROUGH THE MEDIUM RANGE PERIOD. AS IT
BUILDS...RIDGE IS TO STRENGTHEN TRADE WINDS CAP...LEADING TO RAPID
EROSION OF AVAILABLE WATER THROUGH THURSDAY MORNING. A PWAT MINIMA
IS TO THEN PERSIST THROUGH THE WEEKEND. AT LOW LEVELS...A RIDGE IS
TO DOMINATE THE FLOW...WITH ASSOCIATED HIGH TO INITIALLY CENTER
OVER THE GULF OF MEXICO. THROUGH SATURDAY MORNING THIS IS TO
RELOCATE BETWEEN BERMUDA-PUERTO RICO. AS IT ROLLS FROM THE
WEST...INITIALLY EXPECTING FRESH NORTHEASTERLY WINDS TO DOMINATE
LOW LEVEL FLOW. BUT AS THE RIDGE/HIGH SETTLES TO THE NORTH...WINDS
ARE TO GRADUALLY VEER TO THE EAST LATER ON THURSDAY. EXCEPT FOR
THE OCCASIONAL TRADE WIND SHOWER...GLOBAL AND HIGH RESOLUTION
REGIONAL MODELS GENERALLY FAVOR FAIR WEATHER CONDITIONS TO PREVAIL
OVER THE NEXT FEW DAYS.

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






000
FXCA20 KWBC 171137
PMDCA

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
636 AM EST WED DEC 17 2014

PRELIMINARY DISCUSSION FOR PUERTO RICO AND THE USVI. BUILDING MID
LEVEL RIDGE IS TO RAPIDLY STRENGTHEN ITS FOOTHOLD ACROSS THE
CENTRAL/EASTERN CARIBBEAN. THIS IS TO THEN BECOME DOMINANT
SYNOPTIC SCALE FEATURE THROUGH THE MEDIUM RANGE PERIOD. AS IT
BUILDS...RIDGE IS TO STRENGTHEN TRADE WINDS CAP...LEADING TO RAPID
EROSION OF AVAILABLE WATER THROUGH THURSDAY MORNING. A PWAT MINIMA
IS TO THEN PERSIST THROUGH THE WEEKEND. AT LOW LEVELS...A RIDGE IS
TO DOMINATE THE FLOW...WITH ASSOCIATED HIGH TO INITIALLY CENTER
OVER THE GULF OF MEXICO. THROUGH SATURDAY MORNING THIS IS TO
RELOCATE BETWEEN BERMUDA-PUERTO RICO. AS IT ROLLS FROM THE
WEST...INITIALLY EXPECTING FRESH NORTHEASTERLY WINDS TO DOMINATE
LOW LEVEL FLOW. BUT AS THE RIDGE/HIGH SETTLES TO THE NORTH...WINDS
ARE TO GRADUALLY VEER TO THE EAST LATER ON THURSDAY. EXCEPT FOR
THE OCCASIONAL TRADE WIND SHOWER...GLOBAL AND HIGH RESOLUTION
REGIONAL MODELS GENERALLY FAVOR FAIR WEATHER CONDITIONS TO PREVAIL
OVER THE NEXT FEW DAYS.

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







000
FXUS01 KWBC 170852
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
351 AM EST WED DEC 17 2014

VALID 12Z WED DEC 17 2014 - 12Z FRI DEC 19 2014


...WIDELY SCATTERED SHOWERS EXPECTED ACROSS THE WESTERN U.S....

...WEATHER WILL BECOME INCREASINGLY ACTIVE OVER THE SOUTH CENTRAL
U.S....

...CONDITIONS WILL REMAIN UNSETTLED FROM THE GREAT LAKES TO THE
NORTHEAST...


MULTIPLE WEAK PIECES OF ENERGY RIPPLING THROUGH THE FLOW ALOFT
WILL TRIGGER WIDELY SCATTERED SHOWERS ACROSS THE WESTERN U.S.
WEDNESDAY AND THURSDAY.  MOISTURE WILL BE EXTREMELY LIMITED WITH
THESE FEATURES...KEEPING PRECIPITATION TOTALS LIGHT AND CONFINED
TO THE FAVORED SLOPES OF THE TERRAIN; HOWEVER...A MORE ROBUST
SYSTEM APPROACHING THE COAST WILL BRING SOME MORE SIGNIFICANT
PRECIPITATION INTO THE PACIFIC NORTHWEST BY LATE THURSDAY OR EARLY
FRIDAY.

UPPER ENERGY SWINGING OUT OF THE SOUTHWEST...COMBINED WITH RETURN
FLOW FROM THE WESTERN GULF...WILL SPREAD PRECIPITATION ACROSS THE
SOUTH CENTRAL U.S. WEDNESDAY INTO THURSDAY.  RUMBLES OF THUNDER
WILL BE POSSIBLE ACROSS TEXAS WHILE A MIX OF SNOW...SLEET...AND
FREEZING RAIN IS EXPECTED WITHIN THE NORTHERN EDGE OF THE
PRECIPITATION SHIELD STRETCHING ACROSS THE CENTRAL PLAINS AND
MIDDLE MISSISSIPPI VALLEY.  UPSTREAM...A SECOND PIECE OF ENERGY
ALOFT WILL CROSS NORTHERN MEXICO AND IS EXPECTED TO IGNITE AN AREA
OF HEAVY RAINS AND THUNDERSTORMS OVER TEXAS BY EARLY FRIDAY.

A SURFACE LOW DEEPENING OFF THE NEW ENGLAND COAST AND LIFTING
TOWARDS THE CANADIAN MARITIMES WILL KEEP CONDITIONS UNSETTLED FROM
THE GREAT LAKES TO THE NORTHEAST THE NEXT FEW DAYS.  ATLANTIC
MOISTURE WRAPPING AROUND THE STRENGTHENING STORM WILL FUEL
WIDESPREAD COASTAL RAINS AND INTERIOR SNOWS.  ALSO...THE WARM
OCEAN AIR MOVING IN OVER COOLER AIR AT THE SURFACE COULD RESULT IN
PERIODS OF FREEZING RAIN ACROSS PORTIONS OF INTERIOR NEW ENGLAND.


GERHARDT


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







000
FXUS01 KWBC 170852
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
351 AM EST WED DEC 17 2014

VALID 12Z WED DEC 17 2014 - 12Z FRI DEC 19 2014


...WIDELY SCATTERED SHOWERS EXPECTED ACROSS THE WESTERN U.S....

...WEATHER WILL BECOME INCREASINGLY ACTIVE OVER THE SOUTH CENTRAL
U.S....

...CONDITIONS WILL REMAIN UNSETTLED FROM THE GREAT LAKES TO THE
NORTHEAST...


MULTIPLE WEAK PIECES OF ENERGY RIPPLING THROUGH THE FLOW ALOFT
WILL TRIGGER WIDELY SCATTERED SHOWERS ACROSS THE WESTERN U.S.
WEDNESDAY AND THURSDAY.  MOISTURE WILL BE EXTREMELY LIMITED WITH
THESE FEATURES...KEEPING PRECIPITATION TOTALS LIGHT AND CONFINED
TO THE FAVORED SLOPES OF THE TERRAIN; HOWEVER...A MORE ROBUST
SYSTEM APPROACHING THE COAST WILL BRING SOME MORE SIGNIFICANT
PRECIPITATION INTO THE PACIFIC NORTHWEST BY LATE THURSDAY OR EARLY
FRIDAY.

UPPER ENERGY SWINGING OUT OF THE SOUTHWEST...COMBINED WITH RETURN
FLOW FROM THE WESTERN GULF...WILL SPREAD PRECIPITATION ACROSS THE
SOUTH CENTRAL U.S. WEDNESDAY INTO THURSDAY.  RUMBLES OF THUNDER
WILL BE POSSIBLE ACROSS TEXAS WHILE A MIX OF SNOW...SLEET...AND
FREEZING RAIN IS EXPECTED WITHIN THE NORTHERN EDGE OF THE
PRECIPITATION SHIELD STRETCHING ACROSS THE CENTRAL PLAINS AND
MIDDLE MISSISSIPPI VALLEY.  UPSTREAM...A SECOND PIECE OF ENERGY
ALOFT WILL CROSS NORTHERN MEXICO AND IS EXPECTED TO IGNITE AN AREA
OF HEAVY RAINS AND THUNDERSTORMS OVER TEXAS BY EARLY FRIDAY.

A SURFACE LOW DEEPENING OFF THE NEW ENGLAND COAST AND LIFTING
TOWARDS THE CANADIAN MARITIMES WILL KEEP CONDITIONS UNSETTLED FROM
THE GREAT LAKES TO THE NORTHEAST THE NEXT FEW DAYS.  ATLANTIC
MOISTURE WRAPPING AROUND THE STRENGTHENING STORM WILL FUEL
WIDESPREAD COASTAL RAINS AND INTERIOR SNOWS.  ALSO...THE WARM
OCEAN AIR MOVING IN OVER COOLER AIR AT THE SURFACE COULD RESULT IN
PERIODS OF FREEZING RAIN ACROSS PORTIONS OF INTERIOR NEW ENGLAND.


GERHARDT


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






000
FXUS01 KWBC 170852
PMDSPD

SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
351 AM EST WED DEC 17 2014

VALID 12Z WED DEC 17 2014 - 12Z FRI DEC 19 2014


...WIDELY SCATTERED SHOWERS EXPECTED ACROSS THE WESTERN U.S....

...WEATHER WILL BECOME INCREASINGLY ACTIVE OVER THE SOUTH CENTRAL
U.S....

...CONDITIONS WILL REMAIN UNSETTLED FROM THE GREAT LAKES TO THE
NORTHEAST...


MULTIPLE WEAK PIECES OF ENERGY RIPPLING THROUGH THE FLOW ALOFT
WILL TRIGGER WIDELY SCATTERED SHOWERS ACROSS THE WESTERN U.S.
WEDNESDAY AND THURSDAY.  MOISTURE WILL BE EXTREMELY LIMITED WITH
THESE FEATURES...KEEPING PRECIPITATION TOTALS LIGHT AND CONFINED
TO THE FAVORED SLOPES OF THE TERRAIN; HOWEVER...A MORE ROBUST
SYSTEM APPROACHING THE COAST WILL BRING SOME MORE SIGNIFICANT
PRECIPITATION INTO THE PACIFIC NORTHWEST BY LATE THURSDAY OR EARLY
FRIDAY.

UPPER ENERGY SWINGING OUT OF THE SOUTHWEST...COMBINED WITH RETURN
FLOW FROM THE WESTERN GULF...WILL SPREAD PRECIPITATION ACROSS THE
SOUTH CENTRAL U.S. WEDNESDAY INTO THURSDAY.  RUMBLES OF THUNDER
WILL BE POSSIBLE ACROSS TEXAS WHILE A MIX OF SNOW...SLEET...AND
FREEZING RAIN IS EXPECTED WITHIN THE NORTHERN EDGE OF THE
PRECIPITATION SHIELD STRETCHING ACROSS THE CENTRAL PLAINS AND
MIDDLE MISSISSIPPI VALLEY.  UPSTREAM...A SECOND PIECE OF ENERGY
ALOFT WILL CROSS NORTHERN MEXICO AND IS EXPECTED TO IGNITE AN AREA
OF HEAVY RAINS AND THUNDERSTORMS OVER TEXAS BY EARLY FRIDAY.

A SURFACE LOW DEEPENING OFF THE NEW ENGLAND COAST AND LIFTING
TOWARDS THE CANADIAN MARITIMES WILL KEEP CONDITIONS UNSETTLED FROM
THE GREAT LAKES TO THE NORTHEAST THE NEXT FEW DAYS.  ATLANTIC
MOISTURE WRAPPING AROUND THE STRENGTHENING STORM WILL FUEL
WIDESPREAD COASTAL RAINS AND INTERIOR SNOWS.  ALSO...THE WARM
OCEAN AIR MOVING IN OVER COOLER AIR AT THE SURFACE COULD RESULT IN
PERIODS OF FREEZING RAIN ACROSS PORTIONS OF INTERIOR NEW ENGLAND.


GERHARDT


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







000
FXUS02 KWBC 170518
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1217 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...


..OVERVIEW AND GUIDANCE PREFERENCES...

ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A POSSIBLE NEGATIVELY TILT TROUGH
SETTING UP OVER THE GREAT LAKES BY CHRISTMAS EVE. A BREAK/BUCKLING
IN THE STRONG WESTERN/CENTRAL PACIFIC JET BY SUNDAY WILL BE THE
IMPETUS FOR AMPLIFYING THE PATTERN DOWNSTREAM OVER THE CONUS. THE
MODELS/ENSEMBLES HAVE WAVERED IN DETAILS BUT HAVE MOSTLY KEPT ON
TOP OF THE PATTERN SHIFTS... WITH SOME OVER/UNDER AMPLIFICATION
EVIDENT AT BOTH LARGER AND SMALLER SCALES. THAT BEING SAID... A
COMPROMISE/BLENDED APPROACH SEEMED PRUDENT... BANKED MOSTLY ON THE
18Z PARALLEL GFS AND 12Z ECMWF/ECENS MEAN THROUGH MONDAY BEFORE
TRENDING TOWARD A GEFS/ECMWF ENSEMBLE MEAN SOLUTION.


...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.


FRACASSO

$$






000
FXUS02 KWBC 170518
PMDEPD

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1217 AM EST WED DEC 17 2014

VALID 12Z SAT DEC 20 2014 - 12Z WED DEC 24 2014

...SOAKING RAIN FOR PORTIONS OF WASHINGTON/OREGON STARTING LATE
THIS WEEKEND...


..OVERVIEW AND GUIDANCE PREFERENCES...

ACTIVE SPLIT-FLOW PATTERN OVER THE CONUS WILL TRANSITION TO A MORE
AMPLIFIED RIDGE/TROUGH WITH A POSSIBLE NEGATIVELY TILT TROUGH
SETTING UP OVER THE GREAT LAKES BY CHRISTMAS EVE. A BREAK/BUCKLING
IN THE STRONG WESTERN/CENTRAL PACIFIC JET BY SUNDAY WILL BE THE
IMPETUS FOR AMPLIFYING THE PATTERN DOWNSTREAM OVER THE CONUS. THE
MODELS/ENSEMBLES HAVE WAVERED IN DETAILS BUT HAVE MOSTLY KEPT ON
TOP OF THE PATTERN SHIFTS... WITH SOME OVER/UNDER AMPLIFICATION
EVIDENT AT BOTH LARGER AND SMALLER SCALES. THAT BEING SAID... A
COMPROMISE/BLENDED APPROACH SEEMED PRUDENT... BANKED MOSTLY ON THE
18Z PARALLEL GFS AND 12Z ECMWF/ECENS MEAN THROUGH MONDAY BEFORE
TRENDING TOWARD A GEFS/ECMWF ENSEMBLE MEAN SOLUTION.


...SENSIBLE WEATHER HIGHLIGHTS...

WITH AN INCREASING JET INTO THE PAC NW THIS WEEKEND INTO MONDAY...
150KTS PLUS... EXPECT A PRETTY WET PERIOD FOR ESPECIALLY COASTAL
WA/OR AND INTO THE CASCADES. NEAR RIGHT ANGLE FLOW INTO THE
TERRAIN COUPLED WITH PW ANOMALIES IN THE +2 TO +3 RANGE SHOULD
HELP MAXIMIZE PRECIP POTENTIAL... WITH SOME HIGHER RES GUIDANCE
SHOWING SEVERAL INCHES OF QPF SAT-MON -- UP TO ABOUT TEN INCHES AT
THE HIGH SIDE OF THE SPREAD. SNOW LEVELS WILL BE FAIRLY HIGH IN
THE PACIFIC AIRMASS BUT WILL ACCUMULATE AT THE HIGHEST PEAKS.

IN THE EAST... THE PESKY SYSTEM FORECAST TO SLIDE OFF THE COAST
WILL LIKELY DEVELOP FAR ENOUGH OFFSHORE TO HAVE LOW IMPACTS ALONG
THE COAST... BUT COULD THROW SOME LIGHT RAIN/SNOW BACK INTO THE
MID-ATLANTIC/NORTHEAST AS IT EXITS INTO THE ATLANTIC.

MID-PERIOD... QUESTIONS FROM THE LAST FEW NIGHTS ABOUT HOW MUCH
ENERGY WOULD DIG/SPLIT INTO N MEXICO AS THE RIDGE BUILDS OFF
CALIFORNIA AND THE TROUGHING DIGS INTO AZ/NM LATE THIS WEEKEND.
TREND HAS BEEN AWAY FROM THE DIGGY SOLUTIONS AND MORE TOWARD WHAT
THE GEFS MEMBERS HAD 48 HRS AGO -- BUT IT APPEARS THAT THE GEFS
AND ECMWF ENSEMBLES CONVERGED SOMEWHAT MIDWAY BETWEEN EACH OF
THEIR FORMER SOLUTIONS. CURRENT 12Z ECMWF ENSEMBLES STILL LAG JUST
BEHIND THE GEFS MEMBERS AND SHOW A BIT MORE AMPLITUDE BUT EVEN A
BLEND BETWEEN THE TWO SIGNALS A NEGATIVELY TILTED TROUGH
DEVELOPING BY NEXT WEDNESDAY... 24 DECEMBER. SLOWER SOLUTIONS
WOULD ALLOW MUCH MORE RAIN TO DEVELOP IN THE SOUTHEAST AHEAD OF
THE TROUGH AXIS. GIVEN ITS TIMING... IMPACTS WILL BE GREATER THAN
AVERAGE. STAY TUNED.


FRACASSO

$$







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