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000
FXCA62 TJSJ 230154 CCA
AFDSJU

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
952 PM AST WED OCT 22 2014

.UPDATE...MINOR CHANGES WERE INTRODUCED TO SHORT TERM GRIDS TO
MATCH CURRENT CONDITIONS. OVERALL...FORECAST PACKAGE ON TRACK.

A GENERALLY FAIR AND MAINLY STABLE WEATHER PATTERN IS EXPECTED TO
PREVAIL OVER THE NEXT FEW DAYS AS MID TO UPPER LEVEL RIDGE PATTERN
HOLDS ACROSS THE AREA...WITH TOMORROW AS THE DRIEST DAY OF THE
NEXT FIVE DAYS. AREAL COVERAGE OF AFTERNOON CONVECTION IS EXPECTED
TO INCREASE SOMEWHAT FRIDAY AND SATURDAY AS TROPICAL WAVE AND
ASSOCIATED MOISTURE MOVE ACROSS THE EASTERN CARIBBEAN. HOWEVER
SUBSIDENCE ALOFT AND BULK OF MOISTURE ASSOCIATED WITH THE WAVE
WELL SOUTH OF THE AREA...SHOULD LIMIT SIGNIFICANT DEVELOPMENT. A
DRIER AIR MASS WILL MOVE IN FROM THE EAST ON SUNDAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL ACROSS THE LOCAL
FLYING AREA THRU THE FCST PERIOD WITH ONLY SLIGHT CHANCE OF
PASSING -SHRA OVERNIGHT. POSSIBLE VCTS ACROSS TJMZ AND TJBQ AFTER
23/18Z. TJSJ 23/00Z INDICATED A LIGHT EASTERLY WIND FLOW ALL THE
WAY FROM THE SURFACE TO AROUND 20K FEET...BECOMING NORTHEASTERLY
AND STRONGER FROM 20-40K FEET.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION.


&&

.PREV DISCUSSION... /ISSUED 324 PM AST WED OCT 22 2014/

SYNOPSIS...A TUTT EXTENDS SOUTHWEST ACROSS THE NORTHERN LEEWARDS
INTO THE EASTERN CARIBBEAN...WITH HIGH PRESSURE RIDGE ALOFT BUILDING
EASTWARD ACROSS THE DOMINICAN REPUBLIC AND INTO THE MONA PASSAGE.
THE BUILDING RIDGE IS TO CONTINUE BUILD ACROSS THE FORECAST AREA
THROUGH EARLY FRIDAY BEFORE WEAKENING. THEREAFTER...THE UPPER TROUGH
IS TO GRADUALLY STRENGTHEN ONCE AGAIN AND BECOME MORE AMPLIFIED
ACROSS THE LESSER ANTILLES OVER THE WEEKEND...AS A TUTT LOW FORMS
OVER THE ISLAND CHAIN EAST OF THE LOCAL REGION. SURFACE HIGH PRESSURE
RIDGE WILL CONTINUE TO WEAKEN AND LIFT FURTHER NORTHEAST AS A LOW
PRESSURE SYSTEM AND ASSOCIATED FRONTAL TROUGH MOVE EASTWARDS ACROSS
THE WESTERN ATLANTIC. A TROPICAL WAVE WITH AXIS NEAR 56W IS FORECAST
TO CROSS THE LESSER ANTILLES LATE THURSDAY THEN MOVE ACROSS THE
EASTERN CARIBBEAN FRIDAY THROUGH SATURDAY.

DISCUSSION...LIMITED MOISTURE AVAILABILITY...MILD SUBSIDENCE AND
UPPER LEVEL CONVERGENT PATTERN ALOFT HAS SO FAR AIDED IN SUPPRESSING
SIGNIFICANT CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS. EXPECT INCREASING
SUBSIDENCE AND SLOT OF DRIER AIR TO BE FILTERED IN ACROSS THE FORECAST
AREAS OVERNIGHT THROUGH THURSDAY. THIS WILL RESULT IN MOST FAIR WEATHER
SKIES WITH ONLY A FEW EARLY MORNING PASSING SHOWERS AND DIURNAL CONVECTION
LIMITED TO MAINLY THE WEST AND NORTHWEST PORTIONS OF PUERTO RICO
AND SOME OF THE ADJACENT ISLANDS.

THE TROPICAL WAVE AND MAJORITY OF ACCOMPANYING MOISTURE IS STILL
FORECAST TO TRACK MAINLY SOUTH OF THE REGION ON FRIDAY AND SATURDAY.
AS SUBSIDENCE AND CONVERGENT PATTERN ALOFT INCREASES OVER THE
NEXT FEW DAYS...THIS SHOULD CONTINUE TO LIMIT/SUPPRESS SIGNIFICANT
MOISTURE ADVECTION AND CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS.
SOME SHOWER AND THUNDERSTORMS MAY DEVELOP ACROSS THE REGIONAL
WATERS AND PARTS OF THE ISLANDS AS THE WAVE PASSES BUT SO FAR NO
SIGNIFICANT OR WIDESPREAD ACTIVITY IS EXPECTED AT THIS TIME.

LONG TERM...EARLY NEXT WEEK MODELS SUGGEST RETURN OF EASTERLY
TRADES WITH TYPICAL PASSING SHOWERS DURING THE EARLY MORNING HOURS.
LATEST GFS MODEL GUIDANCE SUGGEST INCREASING PWAT VALUES AND BETTER
CHANCE FOR SHOWERS AND THUNDERSTORM DEVELOPMENT ACROSS THE REGION
BY THE MIDDLE AND LATTER PART OF NEXT WEEK WITH THE APPROACH OF
ANOTHER TROPICAL WAVE. UNTIL THEN...LOCAL AND DIURNAL EFFECTS WILL
CONTINUE TO BE THE MAIN DRIVING FORCE FOR ISOLATED TO SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS EACH DAY.

AVIATION...VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH
POSSIBLE VCTS ACROSS TJMZ AND TJBQ TIL 22/23Z. SFC WINDS PREVAILING
FROM THE EAST WITH SEA BREEZE VARIATIONS UNTIL 22/23Z...WINDS
DECREASING OVERNIGHT...GENERALLY AROUND 5 TO 10 KTS. SLIGHT CHANCE
OF PASSING -SHRA OVERNIGHT ACROSS THE LOCAL AREA.

MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  90  76  88 /  10  20  40  40
STT  77  89  78  88 /  20  20  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

72/23






000
FXCA62 TJSJ 230154 CCA
AFDSJU

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
952 PM AST WED OCT 22 2014

.UPDATE...MINOR CHANGES WERE INTRODUCED TO SHORT TERM GRIDS TO
MATCH CURRENT CONDITIONS. OVERALL...FORECAST PACKAGE ON TRACK.

A GENERALLY FAIR AND MAINLY STABLE WEATHER PATTERN IS EXPECTED TO
PREVAIL OVER THE NEXT FEW DAYS AS MID TO UPPER LEVEL RIDGE PATTERN
HOLDS ACROSS THE AREA...WITH TOMORROW AS THE DRIEST DAY OF THE
NEXT FIVE DAYS. AREAL COVERAGE OF AFTERNOON CONVECTION IS EXPECTED
TO INCREASE SOMEWHAT FRIDAY AND SATURDAY AS TROPICAL WAVE AND
ASSOCIATED MOISTURE MOVE ACROSS THE EASTERN CARIBBEAN. HOWEVER
SUBSIDENCE ALOFT AND BULK OF MOISTURE ASSOCIATED WITH THE WAVE
WELL SOUTH OF THE AREA...SHOULD LIMIT SIGNIFICANT DEVELOPMENT. A
DRIER AIR MASS WILL MOVE IN FROM THE EAST ON SUNDAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL ACROSS THE LOCAL
FLYING AREA THRU THE FCST PERIOD WITH ONLY SLIGHT CHANCE OF
PASSING -SHRA OVERNIGHT. POSSIBLE VCTS ACROSS TJMZ AND TJBQ AFTER
23/18Z. TJSJ 23/00Z INDICATED A LIGHT EASTERLY WIND FLOW ALL THE
WAY FROM THE SURFACE TO AROUND 20K FEET...BECOMING NORTHEASTERLY
AND STRONGER FROM 20-40K FEET.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION.


&&

.PREV DISCUSSION... /ISSUED 324 PM AST WED OCT 22 2014/

SYNOPSIS...A TUTT EXTENDS SOUTHWEST ACROSS THE NORTHERN LEEWARDS
INTO THE EASTERN CARIBBEAN...WITH HIGH PRESSURE RIDGE ALOFT BUILDING
EASTWARD ACROSS THE DOMINICAN REPUBLIC AND INTO THE MONA PASSAGE.
THE BUILDING RIDGE IS TO CONTINUE BUILD ACROSS THE FORECAST AREA
THROUGH EARLY FRIDAY BEFORE WEAKENING. THEREAFTER...THE UPPER TROUGH
IS TO GRADUALLY STRENGTHEN ONCE AGAIN AND BECOME MORE AMPLIFIED
ACROSS THE LESSER ANTILLES OVER THE WEEKEND...AS A TUTT LOW FORMS
OVER THE ISLAND CHAIN EAST OF THE LOCAL REGION. SURFACE HIGH PRESSURE
RIDGE WILL CONTINUE TO WEAKEN AND LIFT FURTHER NORTHEAST AS A LOW
PRESSURE SYSTEM AND ASSOCIATED FRONTAL TROUGH MOVE EASTWARDS ACROSS
THE WESTERN ATLANTIC. A TROPICAL WAVE WITH AXIS NEAR 56W IS FORECAST
TO CROSS THE LESSER ANTILLES LATE THURSDAY THEN MOVE ACROSS THE
EASTERN CARIBBEAN FRIDAY THROUGH SATURDAY.

DISCUSSION...LIMITED MOISTURE AVAILABILITY...MILD SUBSIDENCE AND
UPPER LEVEL CONVERGENT PATTERN ALOFT HAS SO FAR AIDED IN SUPPRESSING
SIGNIFICANT CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS. EXPECT INCREASING
SUBSIDENCE AND SLOT OF DRIER AIR TO BE FILTERED IN ACROSS THE FORECAST
AREAS OVERNIGHT THROUGH THURSDAY. THIS WILL RESULT IN MOST FAIR WEATHER
SKIES WITH ONLY A FEW EARLY MORNING PASSING SHOWERS AND DIURNAL CONVECTION
LIMITED TO MAINLY THE WEST AND NORTHWEST PORTIONS OF PUERTO RICO
AND SOME OF THE ADJACENT ISLANDS.

THE TROPICAL WAVE AND MAJORITY OF ACCOMPANYING MOISTURE IS STILL
FORECAST TO TRACK MAINLY SOUTH OF THE REGION ON FRIDAY AND SATURDAY.
AS SUBSIDENCE AND CONVERGENT PATTERN ALOFT INCREASES OVER THE
NEXT FEW DAYS...THIS SHOULD CONTINUE TO LIMIT/SUPPRESS SIGNIFICANT
MOISTURE ADVECTION AND CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS.
SOME SHOWER AND THUNDERSTORMS MAY DEVELOP ACROSS THE REGIONAL
WATERS AND PARTS OF THE ISLANDS AS THE WAVE PASSES BUT SO FAR NO
SIGNIFICANT OR WIDESPREAD ACTIVITY IS EXPECTED AT THIS TIME.

LONG TERM...EARLY NEXT WEEK MODELS SUGGEST RETURN OF EASTERLY
TRADES WITH TYPICAL PASSING SHOWERS DURING THE EARLY MORNING HOURS.
LATEST GFS MODEL GUIDANCE SUGGEST INCREASING PWAT VALUES AND BETTER
CHANCE FOR SHOWERS AND THUNDERSTORM DEVELOPMENT ACROSS THE REGION
BY THE MIDDLE AND LATTER PART OF NEXT WEEK WITH THE APPROACH OF
ANOTHER TROPICAL WAVE. UNTIL THEN...LOCAL AND DIURNAL EFFECTS WILL
CONTINUE TO BE THE MAIN DRIVING FORCE FOR ISOLATED TO SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS EACH DAY.

AVIATION...VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH
POSSIBLE VCTS ACROSS TJMZ AND TJBQ TIL 22/23Z. SFC WINDS PREVAILING
FROM THE EAST WITH SEA BREEZE VARIATIONS UNTIL 22/23Z...WINDS
DECREASING OVERNIGHT...GENERALLY AROUND 5 TO 10 KTS. SLIGHT CHANCE
OF PASSING -SHRA OVERNIGHT ACROSS THE LOCAL AREA.

MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  90  76  88 /  10  20  40  40
STT  77  89  78  88 /  20  20  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

72/23






000
FXCA62 TJSJ 230141
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
941 PM AST WED OCT 22 2014

.UPDATE...MINOR CHANGES WERE INTRODUCED TO SHORT TERM GRIDS TO
MATCH CURRENT CONDITIONS. OVERALL...FORECAST PACKAGE ON TRACK.

A GENERAL FAIR AND MAINLY STABLE WEATHER PATTERN IS EXPECTED TO
PREVAIL OVER THE NEXT FEW DAYS AS MID TO UPPER LEVEL RIDGE PATTERN
HOLDS ACROSS THE AREA...WITH TOMORROW AS THE DRIEST DAY OF THE
NEXT FIVE DAYS. AREAL COVERAGE OF AFTERNOON CONVECTION IS EXPECTED
TO INCREASE SOMEWHAT FRIDAY AND SATURDAY AS TROPICAL WAVE AND
ASSOCIATED MOISTURE MOVE ACROSS THE EASTERN CARIBBEAN. HOWEVER
SUBSIDENCE ALOFT AND BULK OF MOISTURE ASSOCIATED WITH THE WAVE
WELL SOUTH OF THE AREA...SHOULD LIMIT SIGNIFICANT DEVELOPMENT. A
DRIER AIR MASS WILL MOVE IN FROM THE EAST ON SUNDAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL ACROSS THE LOCAL
FLYING AREA THRU THE FCST PERIOD WITH ONLY SLIGHT CHANCE OF
PASSING -SHRA OVERNIGHT. POSSIBLE VCTS ACROSS TJMZ AND TJBQ AFTER
23/18Z. TJSJ 23/00Z INDICATED A LIGHT EASTERLY WIND FLOW ALL THE
WAY FROM THE SURFACE TO AROUND 20K FEET...BECOMING NORTHEASTERLY
AND STRONGER FROM 20-40K FEET.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION.


&&

.PREV DISCUSSION... /ISSUED 324 PM AST WED OCT 22 2014/

SYNOPSIS...A TUTT EXTENDS SOUTHWEST ACROSS THE NORTHERN LEEWARDS
INTO THE EASTERN CARIBBEAN...WITH HIGH PRESSURE RIDGE ALOFT BUILDING
EASTWARD ACROSS THE DOMINICAN REPUBLIC AND INTO THE MONA PASSAGE.
THE BUILDING RIDGE IS TO CONTINUE BUILD ACROSS THE FORECAST AREA
THROUGH EARLY FRIDAY BEFORE WEAKENING. THEREAFTER...THE UPPER TROUGH
IS TO GRADUALLY STRENGTHEN ONCE AGAIN AND BECOME MORE AMPLIFIED
ACROSS THE LESSER ANTILLES OVER THE WEEKEND...AS A TUTT LOW FORMS
OVER THE ISLAND CHAIN EAST OF THE LOCAL REGION. SURFACE HIGH PRESSURE
RIDGE WILL CONTINUE TO WEAKEN AND LIFT FURTHER NORTHEAST AS A LOW
PRESSURE SYSTEM AND ASSOCIATED FRONTAL TROUGH MOVE EASTWARDS ACROSS
THE WESTERN ATLANTIC. A TROPICAL WAVE WITH AXIS NEAR 56W IS FORECAST
TO CROSS THE LESSER ANTILLES LATE THURSDAY THEN MOVE ACROSS THE
EASTERN CARIBBEAN FRIDAY THROUGH SATURDAY.

DISCUSSION...LIMITED MOISTURE AVAILABILITY...MILD SUBSIDENCE AND
UPPER LEVEL CONVERGENT PATTERN ALOFT HAS SO FAR AIDED IN SUPPRESSING
SIGNIFICANT CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS. EXPECT INCREASING
SUBSIDENCE AND SLOT OF DRIER AIR TO BE FILTERED IN ACROSS THE FORECAST
AREAS OVERNIGHT THROUGH THURSDAY. THIS WILL RESULT IN MOST FAIR WEATHER
SKIES WITH ONLY A FEW EARLY MORNING PASSING SHOWERS AND DIURNAL CONVECTION
LIMITED TO MAINLY THE WEST AND NORTHWEST PORTIONS OF PUERTO RICO
AND SOME OF THE ADJACENT ISLANDS.

THE TROPICAL WAVE AND MAJORITY OF ACCOMPANYING MOISTURE IS STILL
FORECAST TO TRACK MAINLY SOUTH OF THE REGION ON FRIDAY AND SATURDAY.
AS SUBSIDENCE AND CONVERGENT PATTERN ALOFT INCREASES OVER THE
NEXT FEW DAYS...THIS SHOULD CONTINUE TO LIMIT/SUPPRESS SIGNIFICANT
MOISTURE ADVECTION AND CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS.
SOME SHOWER AND THUNDERSTORMS MAY DEVELOP ACROSS THE REGIONAL
WATERS AND PARTS OF THE ISLANDS AS THE WAVE PASSES BUT SO FAR NO
SIGNIFICANT OR WIDESPREAD ACTIVITY IS EXPECTED AT THIS TIME.

LONG TERM...EARLY NEXT WEEK MODELS SUGGEST RETURN OF EASTERLY
TRADES WITH TYPICAL PASSING SHOWERS DURING THE EARLY MORNING HOURS.
LATEST GFS MODEL GUIDANCE SUGGEST INCREASING PWAT VALUES AND BETTER
CHANCE FOR SHOWERS AND THUNDERSTORM DEVELOPMENT ACROSS THE REGION
BY THE MIDDLE AND LATTER PART OF NEXT WEEK WITH THE APPROACH OF
ANOTHER TROPICAL WAVE. UNTIL THEN...LOCAL AND DIURNAL EFFECTS WILL
CONTINUE TO BE THE MAIN DRIVING FORCE FOR ISOLATED TO SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS EACH DAY.

AVIATION...VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH
POSSIBLE VCTS ACROSS TJMZ AND TJBQ TIL 22/23Z. SFC WINDS PREVAILING
FROM THE EAST WITH SEA BREEZE VARIATIONS UNTIL 22/23Z...WINDS
DECREASING OVERNIGHT...GENERALLY AROUND 5 TO 10 KTS. SLIGHT CHANCE
OF PASSING -SHRA OVERNIGHT ACROSS THE LOCAL AREA.

MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  90  76  88 /  10  20  40  40
STT  77  89  78  88 /  20  20  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

72/23






000
FXCA62 TJSJ 230141
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
941 PM AST WED OCT 22 2014

.UPDATE...MINOR CHANGES WERE INTRODUCED TO SHORT TERM GRIDS TO
MATCH CURRENT CONDITIONS. OVERALL...FORECAST PACKAGE ON TRACK.

A GENERAL FAIR AND MAINLY STABLE WEATHER PATTERN IS EXPECTED TO
PREVAIL OVER THE NEXT FEW DAYS AS MID TO UPPER LEVEL RIDGE PATTERN
HOLDS ACROSS THE AREA...WITH TOMORROW AS THE DRIEST DAY OF THE
NEXT FIVE DAYS. AREAL COVERAGE OF AFTERNOON CONVECTION IS EXPECTED
TO INCREASE SOMEWHAT FRIDAY AND SATURDAY AS TROPICAL WAVE AND
ASSOCIATED MOISTURE MOVE ACROSS THE EASTERN CARIBBEAN. HOWEVER
SUBSIDENCE ALOFT AND BULK OF MOISTURE ASSOCIATED WITH THE WAVE
WELL SOUTH OF THE AREA...SHOULD LIMIT SIGNIFICANT DEVELOPMENT. A
DRIER AIR MASS WILL MOVE IN FROM THE EAST ON SUNDAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL ACROSS THE LOCAL
FLYING AREA THRU THE FCST PERIOD WITH ONLY SLIGHT CHANCE OF
PASSING -SHRA OVERNIGHT. POSSIBLE VCTS ACROSS TJMZ AND TJBQ AFTER
23/18Z. TJSJ 23/00Z INDICATED A LIGHT EASTERLY WIND FLOW ALL THE
WAY FROM THE SURFACE TO AROUND 20K FEET...BECOMING NORTHEASTERLY
AND STRONGER FROM 20-40K FEET.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION.


&&

.PREV DISCUSSION... /ISSUED 324 PM AST WED OCT 22 2014/

SYNOPSIS...A TUTT EXTENDS SOUTHWEST ACROSS THE NORTHERN LEEWARDS
INTO THE EASTERN CARIBBEAN...WITH HIGH PRESSURE RIDGE ALOFT BUILDING
EASTWARD ACROSS THE DOMINICAN REPUBLIC AND INTO THE MONA PASSAGE.
THE BUILDING RIDGE IS TO CONTINUE BUILD ACROSS THE FORECAST AREA
THROUGH EARLY FRIDAY BEFORE WEAKENING. THEREAFTER...THE UPPER TROUGH
IS TO GRADUALLY STRENGTHEN ONCE AGAIN AND BECOME MORE AMPLIFIED
ACROSS THE LESSER ANTILLES OVER THE WEEKEND...AS A TUTT LOW FORMS
OVER THE ISLAND CHAIN EAST OF THE LOCAL REGION. SURFACE HIGH PRESSURE
RIDGE WILL CONTINUE TO WEAKEN AND LIFT FURTHER NORTHEAST AS A LOW
PRESSURE SYSTEM AND ASSOCIATED FRONTAL TROUGH MOVE EASTWARDS ACROSS
THE WESTERN ATLANTIC. A TROPICAL WAVE WITH AXIS NEAR 56W IS FORECAST
TO CROSS THE LESSER ANTILLES LATE THURSDAY THEN MOVE ACROSS THE
EASTERN CARIBBEAN FRIDAY THROUGH SATURDAY.

DISCUSSION...LIMITED MOISTURE AVAILABILITY...MILD SUBSIDENCE AND
UPPER LEVEL CONVERGENT PATTERN ALOFT HAS SO FAR AIDED IN SUPPRESSING
SIGNIFICANT CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS. EXPECT INCREASING
SUBSIDENCE AND SLOT OF DRIER AIR TO BE FILTERED IN ACROSS THE FORECAST
AREAS OVERNIGHT THROUGH THURSDAY. THIS WILL RESULT IN MOST FAIR WEATHER
SKIES WITH ONLY A FEW EARLY MORNING PASSING SHOWERS AND DIURNAL CONVECTION
LIMITED TO MAINLY THE WEST AND NORTHWEST PORTIONS OF PUERTO RICO
AND SOME OF THE ADJACENT ISLANDS.

THE TROPICAL WAVE AND MAJORITY OF ACCOMPANYING MOISTURE IS STILL
FORECAST TO TRACK MAINLY SOUTH OF THE REGION ON FRIDAY AND SATURDAY.
AS SUBSIDENCE AND CONVERGENT PATTERN ALOFT INCREASES OVER THE
NEXT FEW DAYS...THIS SHOULD CONTINUE TO LIMIT/SUPPRESS SIGNIFICANT
MOISTURE ADVECTION AND CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS.
SOME SHOWER AND THUNDERSTORMS MAY DEVELOP ACROSS THE REGIONAL
WATERS AND PARTS OF THE ISLANDS AS THE WAVE PASSES BUT SO FAR NO
SIGNIFICANT OR WIDESPREAD ACTIVITY IS EXPECTED AT THIS TIME.

LONG TERM...EARLY NEXT WEEK MODELS SUGGEST RETURN OF EASTERLY
TRADES WITH TYPICAL PASSING SHOWERS DURING THE EARLY MORNING HOURS.
LATEST GFS MODEL GUIDANCE SUGGEST INCREASING PWAT VALUES AND BETTER
CHANCE FOR SHOWERS AND THUNDERSTORM DEVELOPMENT ACROSS THE REGION
BY THE MIDDLE AND LATTER PART OF NEXT WEEK WITH THE APPROACH OF
ANOTHER TROPICAL WAVE. UNTIL THEN...LOCAL AND DIURNAL EFFECTS WILL
CONTINUE TO BE THE MAIN DRIVING FORCE FOR ISOLATED TO SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS EACH DAY.

AVIATION...VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH
POSSIBLE VCTS ACROSS TJMZ AND TJBQ TIL 22/23Z. SFC WINDS PREVAILING
FROM THE EAST WITH SEA BREEZE VARIATIONS UNTIL 22/23Z...WINDS
DECREASING OVERNIGHT...GENERALLY AROUND 5 TO 10 KTS. SLIGHT CHANCE
OF PASSING -SHRA OVERNIGHT ACROSS THE LOCAL AREA.

MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  90  76  88 /  10  20  40  40
STT  77  89  78  88 /  20  20  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

72/23






000
FXCA62 TJSJ 221924
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
324 PM AST WED OCT 22 2014

.SYNOPSIS...A TUTT EXTENDS SOUTHWEST ACROSS THE NORTHERN LEEWARDS
INTO THE EASTERN CARIBBEAN...WITH HIGH PRESSURE RIDGE ALOFT BUILDING
EASTWARD ACROSS THE DOMINICAN REPUBLIC AND INTO THE MONA PASSAGE.
THE BUILDING RIDGE IS TO CONTINUE BUILD ACROSS THE FORECAST AREA
THROUGH EARLY FRIDAY BEFORE WEAKENING. THEREAFTER...THE UPPER TROUGH
IS TO GRADUALLY STRENGTHEN ONCE AGAIN AND BECOME MORE AMPLIFIED
ACROSS THE LESSER ANTILLES OVER THE WEEKEND...AS A TUTT LOW FORMS
OVER THE ISLAND CHAIN EAST OF THE LOCAL REGION. SURFACE HIGH PRESSURE
RIDGE WILL CONTINUE TO WEAKEN AND LIFT FURTHER NORTHEAST AS A LOW
PRESSURE SYSTEM AND ASSOCIATED FRONTAL TROUGH MOVE EASTWARDS ACROSS
THE WESTERN ATLANTIC. A TROPICAL WAVE WITH AXIS NEAR 56W IS FORECAST
TO CROSS THE LESSER ANTILLES LATE THURSDAY THEN MOVE ACROSS THE
EASTERN CARIBBEAN FRIDAY THROUGH SATURDAY.

&&

.DISCUSSION...LIMITED MOISTURE AVAILABILITY...MILD SUBSIDENCE AND
UPPER LEVEL CONVERGENT PATTERN ALOFT HAS SO FAR AIDED IN SUPPRESSING
SIGNIFICANT CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS. EXPECT INCREASING
SUBSIDENCE AND SLOT OF DRIER AIR TO BE FILTERED IN ACROSS THE FORECAST
AREAS OVERNIGHT THROUGH THURSDAY. THIS WILL RESULT IN MOST FAIR WEATHER
SKIES WITH ONLY A FEW EARLY MORNING PASSING SHOWERS AND DIURNAL CONVECTION
LIMITED TO MAINLY THE WEST AND NORTHWEST PORTIONS OF PUERTO RICO
AND SOME OF THE ADJACENT ISLANDS.

THE TROPICAL WAVE AND MAJORITY OF ACCOMPANYING MOISTURE IS STILL
FORECAST TO TRACK MAINLY SOUTH OF THE REGION ON FRIDAY AND SATURDAY.
AS SUBSIDENCE AND CONVERGENT PATTERN ALOFT INCREASES OVER THE
NEXT FEW DAYS...THIS SHOULD CONTINUE TO LIMIT/SUPPRESS SIGNIFICANT
MOISTURE ADVECTION AND CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS.
SOME SHOWER AND THUNDERSTORMS MAY DEVELOP ACROSS THE REGIONAL
WATERS AND PARTS OF THE ISLANDS AS THE WAVE PASSES BUT SO FAR NO
SIGNIFICANT OR WIDESPREAD ACTIVITY IS EXPECTED AT THIS TIME.

LONG TERM...EARLY NEXT WEEK MODELS SUGGEST RETURN OF EASTERLY
TRADES WITH TYPICAL PASSING SHOWERS DURING THE EARLY MORNING HOURS.
LATEST GFS MODEL GUIDANCE SUGGEST INCREASING PWAT VALUES AND BETTER
CHANCE FOR SHOWERS AND THUNDERSTORM DEVELOPMENT ACROSS THE REGION
BY THE MIDDLE AND LATTER PART OF NEXT WEEK WITH THE APPROACH OF
ANOTHER TROPICAL WAVE. UNTIL THEN...LOCAL AND DIURNAL EFFECTS WILL
CONTINUE TO BE THE MAIN DRIVING FORCE FOR ISOLATED TO SCATTERED
SHOWER ACTIVITY AND ISOLATED THUNDERSTORMS EACH DAY.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH
POSSIBLE VCTS ACROSS TJMZ AND TJBQ TIL 22/23Z. SFC WINDS PREVAILING
FROM THE EAST WITH SEA BREEZE VARIATIONS UNTIL 22/23Z...WINDS
DECREASING OVERNIGHT...GENERALLY AROUND 5 TO 10 KTS. SLIGHT CHANCE
OF PASSING -SHRA OVERNIGHT ACROSS THE LOCAL AREA.

&&

.MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  90  76  88 /  10  20  40  40
STT  77  89  78  88 /  20  20  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

25/09






000
FXCA62 TJSJ 221535
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1135 AM AST WED OCT 22 2014

.UPDATE...NO SIGNIFICANT CHANGES FROM PREVIOUS DISCUSSION. LATEST
GUIDANCE AND CURRENT OBSERVATIONS ARE IN AGREEMENT WITH THE
INHERITED FORECAST. THE DEVELOPMENT OF SHOWERS AND ISOLATED
THUNDERSTORMS IN THE AFTERNOON ARE EXPECTED MAINLY IN THE
WEST AND NORTHWESTERN SECTIONS OF PR.

VISIBLE SATELLITE SHOWS CLOUDINESS INCREASING ACROSS THE LOCAL
AREA DUE TO OROGRAPHIC LIFTING...CAUSING CLOUDS TO STREAM OFF THE
USVI...VIEQUES AND CULEBRA. HOWEVER THE WESTERN AND NORTHWESTERN
SECTIONS OF PR SHOULD DEVELOP CLOUDINESS JUST AROUND NOON...AS THE
SEA BREEZE CONVERGENCE ALSO PLAYS A ROLE. OTHER THAN THAT...ONLY
PASSING SHOWERS ARE POSSIBLE OR EXPECTED ELSEWHERE.


&&

.AVIATION...NO CHANGES FROM PREVIOUS DISCUSSION. VCTS FOR TJBQ AND
TJMZ IN THE AFTERNOON. TEMPO GROUPS NOT PRESENT AT THIS TIME DUE
TO SOME UNCERTAINTY ON TIMING AND EXACT LOCATION...BUT TSRA IS
EXPECTED IN THE AREA. ALSO...CURRENT WEATHER IS CONDUCIVE FOR FAIR
WEATHER WATERSPOUTS IN THE LOCAL FLYING AREA. WX CONDS EXPECTED TO
IMPROVE THIS EVENING. CURRENT WINDS PREVAILING FROM THE EAST TO
E-SE AT 10-15 KTS...DIMINISHING OVERNIGHT TO 5-10 KTS.


&&

.MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.


&&

.PREV DISCUSSION... /ISSUED 508 AM AST WED OCT 22 2014/

SYNOPSIS...UPPER TROUGH EXTENDING FROM THE CENTRAL ATLANTIC
SOUTHWEST INTO THE LEEWARD ISLANDS WILL REMAIN EAST OF THE LOCAL
AREA OVER THE NEXT FEW DAYS. MID LEVEL RIDGE WILL HOLD ACROSS THE
EAST AND CENTRAL CARIBBEAN THROUGH THE END OF THE WEEK. THE TROUGH
ALOFT EAST OF THE AREA WILL COMBINE WITH THE MID LEVEL RIDGE TO
FAVOR A SUBSIDENCE PATTERN ACROSS THE LOCAL REGION THROUGH AT
LEAST SUNDAY. A TROPICAL WAVE WILL MOVE ACROSS THE EASTERN CARIBBEAN
REGION ON FRIDAY...HOWEVER THE BULK OF THE MOISTURE WILL REMAIN
OVER THE CARIBBEAN WATERS.

DISCUSSION...TROUGHINESS ALOFT JUST EAST OF THE FORECAST AREA
HAS ENHANCED THE TRADE WIND SHOWERS ACROSS THE LOCAL CARIBBEAN
WATERS SINCE MIDNIGHT. DOPPLER RADAR SHOWED SCATTERED SHOWERS
MOVING EASTWARD ACROSS THE REGIONAL WATERS EARLY THIS MORNING.
THIS ACTIVITY IS EXPECTED TO DIMINISH LATER THIS MORNING AS UPPER
TROUGH SETTLES OVER LEEWARD ISLANDS. GFS ENSEMBLE SUGGEST THAT THE
OVERALL MOISTURE WILL DECREASE AS THE AFOREMENTIONED MID LEVEL
RIDGE BUILD ACROSS THE NORTHEAST CARIBBEAN ISLANDS. THIS RIDGE
WILL INDUCE A SUBSIDENCE INVERSION OVER THE LOCAL ISLANDS...
ALLOWING THE GRADUAL EROSION OF AVAILABLE MOISTURE. ANY CONVECTION
THAT DEVELOPS THIS AFTERNOON WILL BE MOSTLY SHALLOW UNDER THE
INFLUENCE OF THE MID LEVEL RIDGE.

THE TROPICAL WAVE NEAR 56 WEST THIS MORNING IS FORECAST TO ENTER
INTO THE EASTERN CARIBBEAN REGION LATE TONIGHT INTO THURSDAY
MORNING. OPERATIONAL MODELS SUGGEST THAT THE WAVE WILL ENCOUNTER
UNFAVORABLE CONDITIONS ALOFT INDUCED BY THE MID-LEVEL RIDGE OVER
THE EASTERN CARIBBEAN. THIS WILL RESULT IN LESS CONVECTION AFFECTING
THE LOCAL REGION FRIDAY AND SATURDAY. IN ADDITION...THE LATEST
GFS GUIDANCE SUGGEST THAT THE BEST MOISTURE CONVERGE ASSOCIATED
WITH THE WAVE WILL REMAIN OVER THE CARIBBEAN WATERS. IN GENERAL...
FAIR WEATHER SHOULD PREVAIL ACROSS THE LOCAL ISLANDS THROUGH THE
END OF THE WEEKEND...WITH SOME SHALLOW CONVECTION DEVELOPING OVER
WESTERN PR EACH AFTERNOON.

AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL THRU THE FORECAST
PERIOD WITH POSSIBLE VCTS NEAR TJMZ AND TJBQ BETWEEN 17Z-21Z.
EASTERLY WIND FLOW OF 5-15 KT CAN BE EXPECTED BELOW 10K FEET.

MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS. PULSES OF A SMALL
NORTHERLY SWELL WILL CONTINUE TO REACH THE LOCAL ATLANTIC WATERS
AND PASSAGES THROUGH THE END OF THE WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  90  77  92  77 /  20  10  20  40
STT  88  78  89  79 /  20  20  20  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

25/09






000
FXCA62 TJSJ 221535
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1135 AM AST WED OCT 22 2014

.UPDATE...NO SIGNIFICANT CHANGES FROM PREVIOUS DISCUSSION. LATEST
GUIDANCE AND CURRENT OBSERVATIONS ARE IN AGREEMENT WITH THE
INHERITED FORECAST. THE DEVELOPMENT OF SHOWERS AND ISOLATED
THUNDERSTORMS IN THE AFTERNOON ARE EXPECTED MAINLY IN THE
WEST AND NORTHWESTERN SECTIONS OF PR.

VISIBLE SATELLITE SHOWS CLOUDINESS INCREASING ACROSS THE LOCAL
AREA DUE TO OROGRAPHIC LIFTING...CAUSING CLOUDS TO STREAM OFF THE
USVI...VIEQUES AND CULEBRA. HOWEVER THE WESTERN AND NORTHWESTERN
SECTIONS OF PR SHOULD DEVELOP CLOUDINESS JUST AROUND NOON...AS THE
SEA BREEZE CONVERGENCE ALSO PLAYS A ROLE. OTHER THAN THAT...ONLY
PASSING SHOWERS ARE POSSIBLE OR EXPECTED ELSEWHERE.


&&

.AVIATION...NO CHANGES FROM PREVIOUS DISCUSSION. VCTS FOR TJBQ AND
TJMZ IN THE AFTERNOON. TEMPO GROUPS NOT PRESENT AT THIS TIME DUE
TO SOME UNCERTAINTY ON TIMING AND EXACT LOCATION...BUT TSRA IS
EXPECTED IN THE AREA. ALSO...CURRENT WEATHER IS CONDUCIVE FOR FAIR
WEATHER WATERSPOUTS IN THE LOCAL FLYING AREA. WX CONDS EXPECTED TO
IMPROVE THIS EVENING. CURRENT WINDS PREVAILING FROM THE EAST TO
E-SE AT 10-15 KTS...DIMINISHING OVERNIGHT TO 5-10 KTS.


&&

.MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS.


&&

.PREV DISCUSSION... /ISSUED 508 AM AST WED OCT 22 2014/

SYNOPSIS...UPPER TROUGH EXTENDING FROM THE CENTRAL ATLANTIC
SOUTHWEST INTO THE LEEWARD ISLANDS WILL REMAIN EAST OF THE LOCAL
AREA OVER THE NEXT FEW DAYS. MID LEVEL RIDGE WILL HOLD ACROSS THE
EAST AND CENTRAL CARIBBEAN THROUGH THE END OF THE WEEK. THE TROUGH
ALOFT EAST OF THE AREA WILL COMBINE WITH THE MID LEVEL RIDGE TO
FAVOR A SUBSIDENCE PATTERN ACROSS THE LOCAL REGION THROUGH AT
LEAST SUNDAY. A TROPICAL WAVE WILL MOVE ACROSS THE EASTERN CARIBBEAN
REGION ON FRIDAY...HOWEVER THE BULK OF THE MOISTURE WILL REMAIN
OVER THE CARIBBEAN WATERS.

DISCUSSION...TROUGHINESS ALOFT JUST EAST OF THE FORECAST AREA
HAS ENHANCED THE TRADE WIND SHOWERS ACROSS THE LOCAL CARIBBEAN
WATERS SINCE MIDNIGHT. DOPPLER RADAR SHOWED SCATTERED SHOWERS
MOVING EASTWARD ACROSS THE REGIONAL WATERS EARLY THIS MORNING.
THIS ACTIVITY IS EXPECTED TO DIMINISH LATER THIS MORNING AS UPPER
TROUGH SETTLES OVER LEEWARD ISLANDS. GFS ENSEMBLE SUGGEST THAT THE
OVERALL MOISTURE WILL DECREASE AS THE AFOREMENTIONED MID LEVEL
RIDGE BUILD ACROSS THE NORTHEAST CARIBBEAN ISLANDS. THIS RIDGE
WILL INDUCE A SUBSIDENCE INVERSION OVER THE LOCAL ISLANDS...
ALLOWING THE GRADUAL EROSION OF AVAILABLE MOISTURE. ANY CONVECTION
THAT DEVELOPS THIS AFTERNOON WILL BE MOSTLY SHALLOW UNDER THE
INFLUENCE OF THE MID LEVEL RIDGE.

THE TROPICAL WAVE NEAR 56 WEST THIS MORNING IS FORECAST TO ENTER
INTO THE EASTERN CARIBBEAN REGION LATE TONIGHT INTO THURSDAY
MORNING. OPERATIONAL MODELS SUGGEST THAT THE WAVE WILL ENCOUNTER
UNFAVORABLE CONDITIONS ALOFT INDUCED BY THE MID-LEVEL RIDGE OVER
THE EASTERN CARIBBEAN. THIS WILL RESULT IN LESS CONVECTION AFFECTING
THE LOCAL REGION FRIDAY AND SATURDAY. IN ADDITION...THE LATEST
GFS GUIDANCE SUGGEST THAT THE BEST MOISTURE CONVERGE ASSOCIATED
WITH THE WAVE WILL REMAIN OVER THE CARIBBEAN WATERS. IN GENERAL...
FAIR WEATHER SHOULD PREVAIL ACROSS THE LOCAL ISLANDS THROUGH THE
END OF THE WEEKEND...WITH SOME SHALLOW CONVECTION DEVELOPING OVER
WESTERN PR EACH AFTERNOON.

AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL THRU THE FORECAST
PERIOD WITH POSSIBLE VCTS NEAR TJMZ AND TJBQ BETWEEN 17Z-21Z.
EASTERLY WIND FLOW OF 5-15 KT CAN BE EXPECTED BELOW 10K FEET.

MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS. PULSES OF A SMALL
NORTHERLY SWELL WILL CONTINUE TO REACH THE LOCAL ATLANTIC WATERS
AND PASSAGES THROUGH THE END OF THE WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  90  77  92  77 /  20  10  20  40
STT  88  78  89  79 /  20  20  20  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

25/09






000
FXCA62 TJSJ 220908
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
508 AM AST WED OCT 22 2014

.SYNOPSIS...UPPER TROUGH EXTENDING FROM THE CENTRAL ATLANTIC
SOUTHWEST INTO THE LEEWARD ISLANDS WILL REMAIN EAST OF THE LOCAL
AREA OVER THE NEXT FEW DAYS. MID LEVEL RIDGE WILL HOLD ACROSS THE
EAST AND CENTRAL CARIBBEAN THROUGH THE END OF THE WEEK. THE TROUGH
ALOFT EAST OF THE AREA WILL COMBINE WITH THE MID LEVEL RIDGE TO
FAVOR A SUBSIDENCE PATTERN ACROSS THE LOCAL REGION THROUGH AT
LEAST SUNDAY. A TROPICAL WAVE WILL MOVE ACROSS THE EASTERN CARIBBEAN
REGION ON FRIDAY...HOWEVER THE BULK OF THE MOISTURE WILL REMAIN
OVER THE CARIBBEAN WATERS.

&&

.DISCUSSION...TROUGHINESS ALOFT JUST EAST OF THE FORECAST AREA
HAS ENHANCED THE TRADE WIND SHOWERS ACROSS THE LOCAL CARIBBEAN
WATERS SINCE MIDNIGHT. DOPPLER RADAR SHOWED SCATTERED SHOWERS
MOVING EASTWARD ACROSS THE REGIONAL WATERS EARLY THIS MORNING.
THIS ACTIVITY IS EXPECTED TO DIMINISH LATER THIS MORNING AS UPPER
TROUGH SETTLES OVER LEEWARD ISLANDS. GFS ENSEMBLE SUGGEST THAT THE
OVERALL MOISTURE WILL DECREASE AS THE AFOREMENTIONED MID LEVEL
RIDGE BUILD ACROSS THE NORTHEAST CARIBBEAN ISLANDS. THIS RIDGE
WILL INDUCE A SUBSIDENCE INVERSION OVER THE LOCAL ISLANDS...
ALLOWING THE GRADUAL EROSION OF AVAILABLE MOISTURE. ANY CONVECTION
THAT DEVELOPS THIS AFTERNOON WILL BE MOSTLY SHALLOW UNDER THE
INFLUENCE OF THE MID LEVEL RIDGE.

THE TROPICAL WAVE NEAR 56 WEST THIS MORNING IS FORECAST TO ENTER
INTO THE EASTERN CARIBBEAN REGION LATE TONIGHT INTO THURSDAY
MORNING. OPERATIONAL MODELS SUGGEST THAT THE WAVE WILL ENCOUNTER
UNFAVORABLE CONDITIONS ALOFT INDUCED BY THE MID-LEVEL RIDGE OVER
THE EASTERN CARIBBEAN. THIS WILL RESULT IN LESS CONVECTION AFFECTING
THE LOCAL REGION FRIDAY AND SATURDAY. IN ADDITION...THE LATEST
GFS GUIDANCE SUGGEST THAT THE BEST MOISTURE CONVERGE ASSOCIATED
WITH THE WAVE WILL REMAIN OVER THE CARIBBEAN WATERS. IN GENERAL...
FAIR WEATHER SHOULD PREVAIL ACROSS THE LOCAL ISLANDS THROUGH THE
END OF THE WEEKEND...WITH SOME SHALLOW CONVECTION DEVELOPING OVER
WESTERN PR EACH AFTERNOON.


&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL THRU THE FORECAST
PERIOD WITH POSSIBLE VCTS NEAR TJMZ AND TJBQ BETWEEN 17Z-21Z.
EASTERLY WIND FLOW OF 5-15 KT CAN BE EXPECTED BELOW 10K FEET.

&&

.MARINE...SEAS 2-4 FEET AND WINDS 15 KNOTS OR LESS CAN BE EXPECTED
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS. PULSES OF A SMALL
NORTHERLY SWELL WILL CONTINUE TO REACH THE LOCAL ATLANTIC WATERS
AND PASSAGES THROUGH THE END OF THE WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  90  77  92  77 /  20  10  20  40
STT  88  78  89  79 /  20  20  20  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

71/11






000
FXCA62 TJSJ 220139
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
939 PM AST TUE OCT 21 2014

.UPDATE...UPPER LEVEL RIDGE WILL CONTINUE TO BUILD ACROSS THE
LOCAL AREA FROM THE WEST AS TROUGH ALOFT CONTINUES TO MOVE
SOUTHEASTWARD...WITH ITS AXIS ESTABLISHING SOUTHEAST OF LOCAL
ISLANDS TOMORROW AFTERNOON. AT MID AND LOW LEVELS...MID LEVEL
RIDGE PATTERN WILL CONTINUE TO PREVAIL DURING THE NEXT FEW DAYS
WITH TROPICAL WAVE NEAR 54W MOVING MAINLY SOUTH OF LOCAL AREA
FRIDAY.

ALTHOUGH UNDER THIS EVOLVING PATTERN THERE IS A LACK OF DYNAMICS...
AVAILABLE MOISTURE WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN
AFTERNOON SHOWERS WITH THUNDERSTORMS EACH DAY. BEST MOISTURE
ADVECTION EXPECTED FRIDAY AND SATURDAY ASSOCIATED WITH THE
TROPICAL WAVE PASSAGE. HOWEVER...BULK OF MOISTURE EXPECTED TO
REMAIN WELL SOUTH OF LOCAL ISLANDS. MINOR CHANGES WERE INTRODUCED
TO FORECAST PACKAGE.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL PREVAIL THRU THE FCST PERIOD
WITH POSSIBLE VCSH ACROSS TNCM/TKPK/TJSJ. TJSJ 22/00Z SOUNDING
INDICATED A LIGHT EASTERLY WIND FLOW FROM THE SURFACE TO 10K
FEET...BECOMING VARIABLE BUT STILL LIGHT FROM 10-35K FEET AND
STRONGER ALOFT.

&&

.MARINE...SEAS UP TO 4 FEET AND WINDS 15 KNOTS OR LESS. SWELL
ACTION DIMINISHING OVERNIGHT.

&&

.PREV DISCUSSION... /ISSUED 311 PM AST TUE OCT 21 2014/

SYNOPSIS...IN THE UPPER LEVELS...A SHORT WAVE TROUGH EXTENDED
SOUTH ACROSS THE REGION INTO THE EAST CENTRAL CARIBBEAN...AS AN
UPPER LEVEL RIDGE WILL SLOWLY BUILD EASTWARD ACROSS THE LOCAL AREA
OVER THE NEXT FEW DAYS AND INTO THE UPCOMING WEEKEND BEFORE WEAKENING.
SURFACE HIGH PRESSURE RIDGE ACROSS THE WESTERN ATLANTIC AND JUST
NORTH OF THE REGION...WILL REMAIN IN PLACE THROUGH THURSDAY...THEN
SLOWLY RETROGRESS INTO THE EASTERN ATLANTIC BY FRIDAY AS AN AREA
OF LOW PRESSURE AND ASSOCIATED COLD FRONT MOVES ACROSS THE WESTERN
ATLANTIC. A TROPICAL WAVE WITH AXIS NOW NEAR 52 WEST AND WEST OF
THE WINDWARD ISLANDS...WILL CONTINUE WESTWARD AND MOVE ACROSS THE
LESSER ANTILLES BY LATE. THIS WAVE WILL THEN MOVE ACROSS THE EASTERN
CARIBBEAN FRIDAY THROUGH SATURDAY WHERE IT IS EXPECTED TO MERGE WITH
THE BROAD EQUATORIAL TROUGH SPREAD ACROSS THE EASTERN CARIBBEAN.

DISCUSSION...LATEST MODEL GUIDANCE AND BLENDED TOTAL PRECIPITABLE
WATER PRODUCT CONTINUED TO SUGGEST DECREASING PWAT VALUES NOW
RANGING BETWEEN 1.50 AND 1.70 INCHES. HOWEVER....STILL SUFFICIENT
POCKETS OF MOISTURE ACROSS PARTS OF THE ISLANDS TO COMBINE WITH
DIURNAL AND LOCAL EFFECTS ALONG WITH THE SHORT WAVE TROUGH TROUGH
MOVING ACROSS THE REGION...TO ALLOW FOR AFTERNOON CONVECTION MAINLY
ACROSS THE WEST INTERIOR SECTIONS OF PUERTO RICO. ACTIVITY SHOULD
HOWEVER DIMINISH BY SUNSET LEAVING MOSTLY CLEAR TO PARTLY SKIES.

OVER THE NEXT COUPLE OF DAYS...DECREASING MOISTURE ADVECTION ALONG
WITH THE BUILDING HIGH PRESSURE RIDGE ALOFT WILL INCREASE UPPER LEVEL
SUBSIDENCE AND HELP TO SUPPRESS AND LIMIT DAYTIME CONVECTION EACH DAY.
HOWEVER SOME ISOLATED TO SCATTERED SHOWERS OR A THUNDERSTORM WILL REMAIN
POSSIBLE ACROSS PARTS OF THE ISLANDS THROUGH THURSDAY.

THE NEXT FEATURE FORECAST TO TRANSPORT MOISTURE TO THE REGION WILL
BE THE PREVIOUSLY MENTIONED TROPICAL WAVE. THIS FEATURE WILL INTERACT
WITH A TUTT WHICH WILL RETROGRESS WESTWARD ACROSS THE LESSER ANTILLES...
AND ENHANCE CONVECTIVE ACTIVITY ACROSS THE EASTERN CARIBBEAN AND
PARTS OF THE LOCAL ISLANDS. THE WAVE IS FORECAST TO CROSS THE WINDWARD
ISLANDS LATE THURSDAY...THEN MOVE ACROSS THE EASTERN CARIBBEAN FRIDAY
THROUGH SATURDAY. ALTHOUGH EXPECT A SLIGHT INCREASE IN MOISTURE ACROSS
THE REGION DURING THE LATTER PART OF THE WEEK...PRESENT SCENARIO
SUGGEST THE BRUNT OF THE MOISTURE ACCOMPANYING THE WAVE SHOULD MOVE
MAINLY SOUTH OF THE AREA. THE DOMINANT RIDGE ALOFT IS TO SUPPRESS
ANY WIDESPREAD CONVECTION ACROSS THE ISLANDS AND COASTAL WATERS
WITH MOST OF THE SHOWERS AND THUNDERSTORM DEVELOPMENT EACH DAY
TO BE FOCUSED ACROSS THE WEST INTERIOR SECTIONS OF PUERTO RICO
OVER THE NEXT SEVERAL DAYS.

AVIATION...AFTER SHRA/TSRA THIS AFTERNOON OVER WESTERN PR. VFR
CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH POSSIBLE VCSH
ACROSS TNCM/TKPK/TJSJ. LIGHT AND VARIABLE WINDS OVERNIGHT.

MARINE...BUOYS ALONG THE NORTH SHORE OF PUERTO RICO AND ACROSS
THE ATLANTIC WATERS CONTINUED TO SUGGEST 3 TO 4 FEET NORTHERLY
SWELL AT 11-14 SECONDS TODAY. HOWEVER THE SWELL ACTION WILL
CONTINUE TO FADE DURING THE EVENING AND OVERNIGHT HOURS. EXPECT
SEAS OF 4 FEET OR LESS AND WINDS 14 KNOTS OR LESS THROUGH WEDNESDAY
WITH FAIRLY TRANQUIL SEAS DURING THE END OF THE WORK WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  89  76  88 /  20  20  10  20
STT  77  89  79  88 /  20  20  20  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

72/23






000
FXCA62 TJSJ 211911
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
311 PM AST TUE OCT 21 2014

.SYNOPSIS...IN THE UPPER LEVELS...A SHORT WAVE TROUGH EXTENDED
SOUTH ACROSS THE REGION INTO THE EAST CENTRAL CARIBBEAN...AS AN
UPPER LEVEL RIDGE WILL SLOWLY BUILD EASTWARD ACROSS THE LOCAL AREA
OVER THE NEXT FEW DAYS AND INTO THE UPCOMING WEEKEND BEFORE WEAKENING.
SURFACE HIGH PRESSURE RIDGE ACROSS THE WESTERN ATLANTIC AND JUST
NORTH OF THE REGION...WILL REMAIN IN PLACE THROUGH THURSDAY...THEN
SLOWLY RETROGRESS INTO THE EASTERN ATLANTIC BY FRIDAY AS AN AREA
OF LOW PRESSURE AND ASSOCIATED COLD FRONT MOVES ACROSS THE WESTERN
ATLANTIC. A TROPICAL WAVE WITH AXIS NOW NEAR 52 WEST AND WEST OF
THE WINDWARD ISLANDS...WILL CONTINUE WESTWARD AND MOVE ACROSS THE
LESSER ANTILLES BY LATE. THIS WAVE WILL THEN MOVE ACROSS THE EASTERN
CARIBBEAN FRIDAY THROUGH SATURDAY WHERE IT IS EXPECTED TO MERGE WITH
THE BROAD EQUATORIAL TROUGH SPREAD ACROSS THE EASTERN CARIBBEAN.

&&

.DISCUSSION...LATEST MODEL GUIDANCE AND BLENDED TOTAL PRECIPITABLE
WATER PRODUCT CONTINUED TO SUGGEST DECREASING PWAT VALUES NOW
RANGING BETWEEN 1.50 AND 1.70 INCHES. HOWEVER....STILL SUFFICIENT
POCKETS OF MOISTURE ACROSS PARTS OF THE ISLANDS TO COMBINE WITH
DIURNAL AND LOCAL EFFECTS ALONG WITH THE SHORT WAVE TROUGH TROUGH
MOVING ACROSS THE REGION...TO ALLOW FOR AFTERNOON CONVECTION MAINLY
ACROSS THE WEST INTERIOR SECTIONS OF PUERTO RICO. ACTIVITY SHOULD
HOWEVER DIMINISH BY SUNSET LEAVING MOSTLY CLEAR TO PARTLY SKIES.

OVER THE NEXT COUPLE OF DAYS...DECREASING MOISTURE ADVECTION ALONG
WITH THE BUILDING HIGH PRESSURE RIDGE ALOFT WILL INCREASE UPPER LEVEL
SUBSIDENCE AND HELP TO SUPPRESS AND LIMIT DAYTIME CONVECTION EACH DAY.
HOWEVER SOME ISOLATED TO SCATTERED SHOWERS OR A THUNDERSTORM WILL REMAIN
POSSIBLE ACROSS PARTS OF THE ISLANDS THROUGH THURSDAY.

THE NEXT FEATURE FORECAST TO TRANSPORT MOISTURE TO THE REGION WILL
BE THE PREVIOUSLY MENTIONED TROPICAL WAVE. THIS FEATURE WILL INTERACT
WITH A TUTT WHICH WILL RETROGRESS WESTWARD ACROSS THE LESSER ANTILLES...
AND ENHANCE CONVECTIVE ACTIVITY ACROSS THE EASTERN CARIBBEAN AND
PARTS OF THE LOCAL ISLANDS. THE WAVE IS FORECAST TO CROSS THE WINDWARD
ISLANDS LATE THURSDAY...THEN MOVE ACROSS THE EASTERN CARIBBEAN FRIDAY
THROUGH SATURDAY. ALTHOUGH EXPECT A SLIGHT INCREASE IN MOISTURE ACROSS
THE REGION DURING THE LATTER PART OF THE WEEK...PRESENT SCENARIO
SUGGEST THE BRUNT OF THE MOISTURE ACCOMPANYING THE WAVE SHOULD MOVE
MAINLY SOUTH OF THE AREA. THE DOMINANT RIDGE ALOFT IS TO SUPPRESS
ANY WIDESPREAD CONVECTION ACROSS THE ISLANDS AND COASTAL WATERS
WITH MOST OF THE SHOWERS AND THUNDERSTORM DEVELOPMENT EACH DAY
TO BE FOCUSED ACROSS THE WEST INTERIOR SECTIONS OF PUERTO RICO
OVER THE NEXT SEVERAL DAYS.

&&

.AVIATION...AFTER SHRA/TSRA THIS AFTERNOON OVER WESTERN PR. VFR
CONDITIONS WILL PREVAIL THRU THE FCST PERIOD WITH POSSIBLE VCSH
ACROSS TNCM/TKPK/TJSJ. LIGHT AND VARIABLE WINDS OVERNIGHT.

&&

.MARINE...BUOYS ALONG THE NORTH SHORE OF PUERTO RICO AND ACROSS
THE ATLANTIC WATERS CONTINUED TO SUGGEST 3 TO 4 FEET NORTHERLY
SWELL AT 11-14 SECONDS TODAY. HOWEVER THE SWELL ACTION WILL
CONTINUE TO FADE DURING THE EVENING AND OVERNIGHT HOURS. EXPECT
SEAS OF 4 FEET OR LESS AND WINDS 14 KNOTS OR LESS THROUGH WEDNESDAY
WITH FAIRLY TRANQUIL SEAS DURING THE END OF THE WORK WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  89  76  88 /  30  30  10  20
STT  77  89  79  88 /  30  30  20  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.

&&

$$

13/09






000
FXCA62 TJSJ 211434
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1034 AM AST TUE OCT 21 2014

.UPDATE...MINOR CHANGES MADE TO SHORT TERM GRIDS. MOSTLY SUNNY TO
PARTLY CLOUDY SKIES HAVE BEEN OBSERVED ACROSS ALL LOCAL ISLANDS
THIS MORNING. A FEW LIGHT PASSING SHOWERS REACHED PORTIONS OF
EASTERN PR AND THE U.S. VIRGIN ISLANDS BUT RAINFALL AMOUNTS WERE
NOT SIGNIFICANT. FOR THE REST OF THE DAY...STREAMERS FORMING OVER
THE USVI...VIEQUES AND CULEBRA WILL CREATE PERIODS OF SHOWERS OVER
THE SURROUNDING WATERS WITH A FEW OF THEM REACHING EASTERN PR.
THEN...AFTERNOON CONVECTION OVER THE CORDILLERA CENTRAL WILL BRING
AGAIN PERIODS OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
AFFECTING THE INTERIOR AND WESTERN QUADRANT OF PR.

&&

.AVIATION...ADDED TEMPO GROUPS TO TJBQ AND TJMZ AS AFTERNOON
CONVECTION SHOULD FOCUS OVER THE WESTERN SIDE OF PR. THE 21/12Z
TJSJ SOUNDING INDICATED A PREVAILING EASTERLY WIND FLOW WITH 15 KT
WINDS BETWEEN 1-5 KFT.

&&

.MARINE...BUOYS ALONG THE NORTH SHORE OF PUERTO RICO ARE STILL
INDICATING A 3-4 FEET NORTH SWELL AT 11-14 SECONDS. HAZARDOUS RIP
CURRENTS ARE STILL POSSIBLE DURING THE REST OF THE DAY. NO CHANGES
TO PREVIOUS FORECAST.

&&

.PREV DISCUSSION... /ISSUED 553 AM AST TUE OCT 21 2014/

SYNOPSIS...A WEAK SHORT WAVE WILL PASS THROUGH THE LOCAL AREA
THIS AFTERNOON FOLLOWED BY NORTH FLOW OVER THE AREA AND RIDGING
NORTH OF THE AREA THAT CONTINUES INTO NEXT WEEK. A TROUGH WILL
EXTEND ACROSS THE LEEWARD ISLANDS FROM A LOW IN THE WESTERN
TROPICAL ATLANTIC. IT WILL SHIFT SOUTHWEST AND ENTER THE EASTERN
CARIBBEAN EARLY NEXT WEEK.

AT MID LEVELS...A RIDGE FROM HIGH PRESSURE OVER THE WESTERN
TROPICAL ATLANTIC EXTENDS EASTWARD INTO THE CARIBBEAN. HIGH
PRESSURE THEN CONTINUES OVER THE EASTERN CARIBBEAN THROUGH
THURSDAY. AN INVERTED TROUGH IN THE WESTERN ATLANTIC WILL DISPLACE
THE HIGH TO THE NORTH AS IT MOVES SLOWLY ACROSS THE CARIBBEAN
SOUTH OF THE LOCAL AREA OVER THE WEEKEND. HIGH PRESSURE SPREADS
OVER THE ATLANTIC WATERS NORTH OF PUERTO RICO AND THE U.S. VIRGIN
ISLANDS THROUGH THE END OF THE MONTH AFTER A LONG WAVE TROUGH AND
CUT-OFF LOW MOVE EAST THROUGH THE WESTERN ATLANTIC NORTH OF THE
AREA.

AT LOWER LEVELS...LOW PRESSURE IN THE SOUTHWEST CARIBBEAN AND
HIGHER PRESSURE NORTH OF THE AREA CONTINUE. A WEAK LOW PRESSURE
ALSO CONTINUES TO WOBBLE AROUND IN A BOX BOUNDED BY 50 AND 60 WEST
LONGITUDE AND 20 AND 30 NORTH LATITUDE UNTIL THURSDAY. EAST
SOUTHEAST TRADE WIND FLOW WILL CONTINUE ACROSS THE AREA OVER THE
WEEKEND WHILE LOW PRESSURES DEVELOP IN THE WESTERN CARIBBEAN AND
MOVE NORTHEAST OVER THE WESTERN TIP OF CUBA THROUGH THE END OF THE
MONTH.

DISCUSSION...A SIMILAR SITUATION TO YESTERDAY ABIDES AGAIN TODAY
WITH SMALL SHOWERS ACROSS THE LOCAL WATERS MOVING IN THE EAST
NORTHEAST TO EASTERLY FLOW AND A SMATTERING OF SMALL SHOWERS
MOVING ACROSS THE U.S. VIRGIN ISLANDS AND THE NORTHEASTERN AND
EASTERN COASTS OF PUERTO RICO. AMOUNTS OF ONE TO TWO HUNDREDTHS
HAVE BEEN NOTED WHERE RAIN HAS FALLEN. ALTHOUGH THERE WILL BE
SLIGHTLY LESS MOISTURE IN THE COLUMN OVER THE AREA TODAY...A WEAK
SHORT WAVE THIS AFTERNOON AND LIFTED INDICES SIMILAR TO YESTERDAY
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS...SOME WITH
VERY HEAVY RAIN...TO INTERIOR AND WESTERN PUERTO RICO WHERE URBAN
AND SMALL STREAM FLOODING IN SOME AREAS IS EXPECTED. ISOLATED
SHOWERS AND MOSTLY SUNNY SKIES WILL BE NOTED ELSEWHERE. NORTHERLY
FLOW ALOFT AND DRIER AIR AT LOWER AND MID LEVELS WILL REDUCE
SHOWERS AND THUNDERSTORMS BOTH WEDNESDAY AND THURSDAY. THE ADDED
SUNSHINE AND THE SHIFT TO SOUTHEASTERLY FLOW IN THE LOWER LEVELS
WILL PUSH TEMPERATURES INTO THE LOWER 90S IN THE SAN JUAN GREATER
METROPOLITAN AREA AND KEEP TEMPERATURES IN THE LOWER 90S IN THE
LOWER ELEVATIONS ON THE SOUTH AND WEST COASTS.

THEN...ON FRIDAY...MOISTURE WILL BEGIN TO INCREASE AND SHOWERS WILL
RETURN IN THE SOUTHEASTERLY FLOW...MAINLY TO NORTHWEST PUERTO RICO
AND NORTH OF THE CORDILLERA CENTRAL. SLIGHTLY DRIER DAYS WILL
BEGIN AGAIN ON SUNDAY AND LAST UNTIL WEDNESDAY OF NEXT WEEK AFTER
A TROUGH AT UPPER LEVELS PASSES SOUTH OF THE AREA AND BETTER
CONDITIONS ARE FOUND IN ITS NORTHEAST QUADRANT.

AVIATION...VFR CONDITIONS ARE EXPECTED THRU THE FCST PERIOD.
WINDS INCREASE TO 8-15 KTS FM THE EAST AFT 21/13Z WITH SEA BREEZE
VARIATIONS. VCSH PSBL AT TJSJ/TISX/TIST TIL EARLY IN THE
AFTERNOON. SHRA/TSRA ARE ONCE AGAIN EXPECTED ACROSS THE CENTRAL
MOUNTAIN RANGE OF PR BETWEEN 21/17-22Z CREATING BRIEF MVFR CONDS
AND MTN OBSCURATIONS... IMPACTING MAINLY TJMZ/TJBQ TAF SITES.

MARINE...GENERALLY DIMINISHING SEAS WILL PREVAIL THROUGH FRIDAY.
OVER THE WEEKEND WAVES FROM THE SOUTHEAST WILL INCREASE IN BOTH
THE CARIBBEAN AND ATLANTIC WATERS...BUT SMALL CRAFT ADVISORIES ARE
NOT EXPECTED THROUGH THE END OF THE MONTH.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  88  78  90  77 /  30  30  30  10
STT  88  79  88  79 /  20  30  30  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

13/09





000
FXCA62 TJSJ 211434
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1034 AM AST TUE OCT 21 2014

.UPDATE...MINOR CHANGES MADE TO SHORT TERM GRIDS. MOSTLY SUNNY TO
PARTLY CLOUDY SKIES HAVE BEEN OBSERVED ACROSS ALL LOCAL ISLANDS
THIS MORNING. A FEW LIGHT PASSING SHOWERS REACHED PORTIONS OF
EASTERN PR AND THE U.S. VIRGIN ISLANDS BUT RAINFALL AMOUNTS WERE
NOT SIGNIFICANT. FOR THE REST OF THE DAY...STREAMERS FORMING OVER
THE USVI...VIEQUES AND CULEBRA WILL CREATE PERIODS OF SHOWERS OVER
THE SURROUNDING WATERS WITH A FEW OF THEM REACHING EASTERN PR.
THEN...AFTERNOON CONVECTION OVER THE CORDILLERA CENTRAL WILL BRING
AGAIN PERIODS OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
AFFECTING THE INTERIOR AND WESTERN QUADRANT OF PR.

&&

.AVIATION...ADDED TEMPO GROUPS TO TJBQ AND TJMZ AS AFTERNOON
CONVECTION SHOULD FOCUS OVER THE WESTERN SIDE OF PR. THE 21/12Z
TJSJ SOUNDING INDICATED A PREVAILING EASTERLY WIND FLOW WITH 15 KT
WINDS BETWEEN 1-5 KFT.

&&

.MARINE...BUOYS ALONG THE NORTH SHORE OF PUERTO RICO ARE STILL
INDICATING A 3-4 FEET NORTH SWELL AT 11-14 SECONDS. HAZARDOUS RIP
CURRENTS ARE STILL POSSIBLE DURING THE REST OF THE DAY. NO CHANGES
TO PREVIOUS FORECAST.

&&

.PREV DISCUSSION... /ISSUED 553 AM AST TUE OCT 21 2014/

SYNOPSIS...A WEAK SHORT WAVE WILL PASS THROUGH THE LOCAL AREA
THIS AFTERNOON FOLLOWED BY NORTH FLOW OVER THE AREA AND RIDGING
NORTH OF THE AREA THAT CONTINUES INTO NEXT WEEK. A TROUGH WILL
EXTEND ACROSS THE LEEWARD ISLANDS FROM A LOW IN THE WESTERN
TROPICAL ATLANTIC. IT WILL SHIFT SOUTHWEST AND ENTER THE EASTERN
CARIBBEAN EARLY NEXT WEEK.

AT MID LEVELS...A RIDGE FROM HIGH PRESSURE OVER THE WESTERN
TROPICAL ATLANTIC EXTENDS EASTWARD INTO THE CARIBBEAN. HIGH
PRESSURE THEN CONTINUES OVER THE EASTERN CARIBBEAN THROUGH
THURSDAY. AN INVERTED TROUGH IN THE WESTERN ATLANTIC WILL DISPLACE
THE HIGH TO THE NORTH AS IT MOVES SLOWLY ACROSS THE CARIBBEAN
SOUTH OF THE LOCAL AREA OVER THE WEEKEND. HIGH PRESSURE SPREADS
OVER THE ATLANTIC WATERS NORTH OF PUERTO RICO AND THE U.S. VIRGIN
ISLANDS THROUGH THE END OF THE MONTH AFTER A LONG WAVE TROUGH AND
CUT-OFF LOW MOVE EAST THROUGH THE WESTERN ATLANTIC NORTH OF THE
AREA.

AT LOWER LEVELS...LOW PRESSURE IN THE SOUTHWEST CARIBBEAN AND
HIGHER PRESSURE NORTH OF THE AREA CONTINUE. A WEAK LOW PRESSURE
ALSO CONTINUES TO WOBBLE AROUND IN A BOX BOUNDED BY 50 AND 60 WEST
LONGITUDE AND 20 AND 30 NORTH LATITUDE UNTIL THURSDAY. EAST
SOUTHEAST TRADE WIND FLOW WILL CONTINUE ACROSS THE AREA OVER THE
WEEKEND WHILE LOW PRESSURES DEVELOP IN THE WESTERN CARIBBEAN AND
MOVE NORTHEAST OVER THE WESTERN TIP OF CUBA THROUGH THE END OF THE
MONTH.

DISCUSSION...A SIMILAR SITUATION TO YESTERDAY ABIDES AGAIN TODAY
WITH SMALL SHOWERS ACROSS THE LOCAL WATERS MOVING IN THE EAST
NORTHEAST TO EASTERLY FLOW AND A SMATTERING OF SMALL SHOWERS
MOVING ACROSS THE U.S. VIRGIN ISLANDS AND THE NORTHEASTERN AND
EASTERN COASTS OF PUERTO RICO. AMOUNTS OF ONE TO TWO HUNDREDTHS
HAVE BEEN NOTED WHERE RAIN HAS FALLEN. ALTHOUGH THERE WILL BE
SLIGHTLY LESS MOISTURE IN THE COLUMN OVER THE AREA TODAY...A WEAK
SHORT WAVE THIS AFTERNOON AND LIFTED INDICES SIMILAR TO YESTERDAY
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS...SOME WITH
VERY HEAVY RAIN...TO INTERIOR AND WESTERN PUERTO RICO WHERE URBAN
AND SMALL STREAM FLOODING IN SOME AREAS IS EXPECTED. ISOLATED
SHOWERS AND MOSTLY SUNNY SKIES WILL BE NOTED ELSEWHERE. NORTHERLY
FLOW ALOFT AND DRIER AIR AT LOWER AND MID LEVELS WILL REDUCE
SHOWERS AND THUNDERSTORMS BOTH WEDNESDAY AND THURSDAY. THE ADDED
SUNSHINE AND THE SHIFT TO SOUTHEASTERLY FLOW IN THE LOWER LEVELS
WILL PUSH TEMPERATURES INTO THE LOWER 90S IN THE SAN JUAN GREATER
METROPOLITAN AREA AND KEEP TEMPERATURES IN THE LOWER 90S IN THE
LOWER ELEVATIONS ON THE SOUTH AND WEST COASTS.

THEN...ON FRIDAY...MOISTURE WILL BEGIN TO INCREASE AND SHOWERS WILL
RETURN IN THE SOUTHEASTERLY FLOW...MAINLY TO NORTHWEST PUERTO RICO
AND NORTH OF THE CORDILLERA CENTRAL. SLIGHTLY DRIER DAYS WILL
BEGIN AGAIN ON SUNDAY AND LAST UNTIL WEDNESDAY OF NEXT WEEK AFTER
A TROUGH AT UPPER LEVELS PASSES SOUTH OF THE AREA AND BETTER
CONDITIONS ARE FOUND IN ITS NORTHEAST QUADRANT.

AVIATION...VFR CONDITIONS ARE EXPECTED THRU THE FCST PERIOD.
WINDS INCREASE TO 8-15 KTS FM THE EAST AFT 21/13Z WITH SEA BREEZE
VARIATIONS. VCSH PSBL AT TJSJ/TISX/TIST TIL EARLY IN THE
AFTERNOON. SHRA/TSRA ARE ONCE AGAIN EXPECTED ACROSS THE CENTRAL
MOUNTAIN RANGE OF PR BETWEEN 21/17-22Z CREATING BRIEF MVFR CONDS
AND MTN OBSCURATIONS... IMPACTING MAINLY TJMZ/TJBQ TAF SITES.

MARINE...GENERALLY DIMINISHING SEAS WILL PREVAIL THROUGH FRIDAY.
OVER THE WEEKEND WAVES FROM THE SOUTHEAST WILL INCREASE IN BOTH
THE CARIBBEAN AND ATLANTIC WATERS...BUT SMALL CRAFT ADVISORIES ARE
NOT EXPECTED THROUGH THE END OF THE MONTH.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  88  78  90  77 /  30  30  30  10
STT  88  79  88  79 /  20  30  30  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

13/09






000
FXCA62 TJSJ 210953
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
553 AM AST TUE OCT 21 2014

.SYNOPSIS...A WEAK SHORT WAVE WILL PASS THROUGH THE LOCAL AREA
THIS AFTERNOON FOLLOWED BY NORTH FLOW OVER THE AREA AND RIDGING
NORTH OF THE AREA THAT CONTINUES INTO NEXT WEEK. A TROUGH WILL
EXTEND ACROSS THE LEEWARD ISLANDS FROM A LOW IN THE WESTERN
TROPICAL ATLANTIC. IT WILL SHIFT SOUTHWEST AND ENTER THE EASTERN
CARIBBEAN EARLY NEXT WEEK.

AT MID LEVELS...A RIDGE FROM HIGH PRESSURE OVER THE WESTERN
TROPICAL ATLANTIC EXTENDS EASTWARD INTO THE CARIBBEAN. HIGH
PRESSURE THEN CONTINUES OVER THE EASTERN CARIBBEAN THROUGH
THURSDAY. AN INVERTED TROUGH IN THE WESTERN ATLANTIC WILL DISPLACE
THE HIGH TO THE NORTH AS IT MOVES SLOWLY ACROSS THE CARIBBEAN
SOUTH OF THE LOCAL AREA OVER THE WEEKEND. HIGH PRESSURE SPREADS
OVER THE ATLANTIC WATERS NORTH OF PUERTO RICO AND THE U.S. VIRGIN
ISLANDS THROUGH THE END OF THE MONTH AFTER A LONG WAVE TROUGH AND
CUT-OFF LOW MOVE EAST THROUGH THE WESTERN ATLANTIC NORTH OF THE
AREA.

AT LOWER LEVELS...LOW PRESSURE IN THE SOUTHWEST CARIBBEAN AND
HIGHER PRESSURE NORTH OF THE AREA CONTINUE. A WEAK LOW PRESSURE
ALSO CONTINUES TO WOBBLE AROUND IN A BOX BOUNDED BY 50 AND 60 WEST
LONGITUDE AND 20 AND 30 NORTH LATITUDE UNTIL THURSDAY. EAST
SOUTHEAST TRADE WIND FLOW WILL CONTINUE ACROSS THE AREA OVER THE
WEEKEND WHILE LOW PRESSURES DEVELOP IN THE WESTERN CARIBBEAN AND
MOVE NORTHEAST OVER THE WESTERN TIP OF CUBA THROUGH THE END OF THE
MONTH.

&&

.DISCUSSION...A SIMILAR SITUATION TO YESTERDAY ABIDES AGAIN TODAY
WITH SMALL SHOWERS ACROSS THE LOCAL WATERS MOVING IN THE EAST
NORTHEAST TO EASTERLY FLOW AND A SMATTERING OF SMALL SHOWERS
MOVING ACROSS THE U.S. VIRGIN ISLANDS AND THE NORTHEASTERN AND
EASTERN COASTS OF PUERTO RICO. AMOUNTS OF ONE TO TWO HUNDREDTHS
HAVE BEEN NOTED WHERE RAIN HAS FALLEN. ALTHOUGH THERE WILL BE
SLIGHTLY LESS MOISTURE IN THE COLUMN OVER THE AREA TODAY...A WEAK
SHORT WAVE THIS AFTERNOON AND LIFTED INDICES SIMILAR TO YESTERDAY
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS...SOME WITH
VERY HEAVY RAIN...TO INTERIOR AND WESTERN PUERTO RICO WHERE URBAN
AND SMALL STREAM FLOODING IN SOME AREAS IS EXPECTED. ISOLATED
SHOWERS AND MOSTLY SUNNY SKIES WILL BE NOTED ELSEWHERE. NORTHERLY
FLOW ALOFT AND DRIER AIR AT LOWER AND MID LEVELS WILL REDUCE
SHOWERS AND THUNDERSTORMS BOTH WEDNESDAY AND THURSDAY. THE ADDED
SUNSHINE AND THE SHIFT TO SOUTHEASTERLY FLOW IN THE LOWER LEVELS
WILL PUSH TEMPERATURES INTO THE LOWER 90S IN THE SAN JUAN GREATER
METROPOLITAN AREA AND KEEP TEMPERATURES IN THE LOWER 90S IN THE
LOWER ELEVATIONS ON THE SOUTH AND WEST COASTS.

THEN...ON FRIDAY...MOISTURE WILL BEGIN TO INCREASE AND SHOWERS WILL
RETURN IN THE SOUTHEASTERLY FLOW...MAINLY TO NORTHWEST PUERTO RICO
AND NORTH OF THE CORDILLERA CENTRAL. SLIGHTLY DRIER DAYS WILL
BEGIN AGAIN ON SUNDAY AND LAST UNTIL WEDNESDAY OF NEXT WEEK AFTER
A TROUGH AT UPPER LEVELS PASSES SOUTH OF THE AREA AND BETTER
CONDITIONS ARE FOUND IN ITS NORTHEAST QUADRANT.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THRU THE FCST PERIOD.
WINDS INCREASE TO 8-15 KTS FM THE EAST AFT 21/13Z WITH SEA BREEZE
VARIATIONS. VCSH PSBL AT TJSJ/TISX/TIST TIL EARLY IN THE
AFTERNOON. SHRA/TSRA ARE ONCE AGAIN EXPECTED ACROSS THE CENTRAL
MOUNTAIN RANGE OF PR BETWEEN 21/17-22Z CREATING BRIEF MVFR CONDS
AND MTN OBSCURATIONS... IMPACTING MAINLY TJMZ/TJBQ TAF SITES.

&&

.MARINE...GENERALLY DIMINISHING SEAS WILL PREVAIL THROUGH FRIDAY.
OVER THE WEEKEND WAVES FROM THE SOUTHEAST WILL INCREASE IN BOTH
THE CARIBBEAN AND ATLANTIC WATERS...BUT SMALL CRAFT ADVISORIES ARE
NOT EXPECTED THROUGH THE END OF THE MONTH.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  88  78  90  77 /  30  30  30  10
STT  88  79  88  79 /  20  30  30  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

27/12





000
FXCA62 TJSJ 210953
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
553 AM AST TUE OCT 21 2014

.SYNOPSIS...A WEAK SHORT WAVE WILL PASS THROUGH THE LOCAL AREA
THIS AFTERNOON FOLLOWED BY NORTH FLOW OVER THE AREA AND RIDGING
NORTH OF THE AREA THAT CONTINUES INTO NEXT WEEK. A TROUGH WILL
EXTEND ACROSS THE LEEWARD ISLANDS FROM A LOW IN THE WESTERN
TROPICAL ATLANTIC. IT WILL SHIFT SOUTHWEST AND ENTER THE EASTERN
CARIBBEAN EARLY NEXT WEEK.

AT MID LEVELS...A RIDGE FROM HIGH PRESSURE OVER THE WESTERN
TROPICAL ATLANTIC EXTENDS EASTWARD INTO THE CARIBBEAN. HIGH
PRESSURE THEN CONTINUES OVER THE EASTERN CARIBBEAN THROUGH
THURSDAY. AN INVERTED TROUGH IN THE WESTERN ATLANTIC WILL DISPLACE
THE HIGH TO THE NORTH AS IT MOVES SLOWLY ACROSS THE CARIBBEAN
SOUTH OF THE LOCAL AREA OVER THE WEEKEND. HIGH PRESSURE SPREADS
OVER THE ATLANTIC WATERS NORTH OF PUERTO RICO AND THE U.S. VIRGIN
ISLANDS THROUGH THE END OF THE MONTH AFTER A LONG WAVE TROUGH AND
CUT-OFF LOW MOVE EAST THROUGH THE WESTERN ATLANTIC NORTH OF THE
AREA.

AT LOWER LEVELS...LOW PRESSURE IN THE SOUTHWEST CARIBBEAN AND
HIGHER PRESSURE NORTH OF THE AREA CONTINUE. A WEAK LOW PRESSURE
ALSO CONTINUES TO WOBBLE AROUND IN A BOX BOUNDED BY 50 AND 60 WEST
LONGITUDE AND 20 AND 30 NORTH LATITUDE UNTIL THURSDAY. EAST
SOUTHEAST TRADE WIND FLOW WILL CONTINUE ACROSS THE AREA OVER THE
WEEKEND WHILE LOW PRESSURES DEVELOP IN THE WESTERN CARIBBEAN AND
MOVE NORTHEAST OVER THE WESTERN TIP OF CUBA THROUGH THE END OF THE
MONTH.

&&

.DISCUSSION...A SIMILAR SITUATION TO YESTERDAY ABIDES AGAIN TODAY
WITH SMALL SHOWERS ACROSS THE LOCAL WATERS MOVING IN THE EAST
NORTHEAST TO EASTERLY FLOW AND A SMATTERING OF SMALL SHOWERS
MOVING ACROSS THE U.S. VIRGIN ISLANDS AND THE NORTHEASTERN AND
EASTERN COASTS OF PUERTO RICO. AMOUNTS OF ONE TO TWO HUNDREDTHS
HAVE BEEN NOTED WHERE RAIN HAS FALLEN. ALTHOUGH THERE WILL BE
SLIGHTLY LESS MOISTURE IN THE COLUMN OVER THE AREA TODAY...A WEAK
SHORT WAVE THIS AFTERNOON AND LIFTED INDICES SIMILAR TO YESTERDAY
WILL BRING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS...SOME WITH
VERY HEAVY RAIN...TO INTERIOR AND WESTERN PUERTO RICO WHERE URBAN
AND SMALL STREAM FLOODING IN SOME AREAS IS EXPECTED. ISOLATED
SHOWERS AND MOSTLY SUNNY SKIES WILL BE NOTED ELSEWHERE. NORTHERLY
FLOW ALOFT AND DRIER AIR AT LOWER AND MID LEVELS WILL REDUCE
SHOWERS AND THUNDERSTORMS BOTH WEDNESDAY AND THURSDAY. THE ADDED
SUNSHINE AND THE SHIFT TO SOUTHEASTERLY FLOW IN THE LOWER LEVELS
WILL PUSH TEMPERATURES INTO THE LOWER 90S IN THE SAN JUAN GREATER
METROPOLITAN AREA AND KEEP TEMPERATURES IN THE LOWER 90S IN THE
LOWER ELEVATIONS ON THE SOUTH AND WEST COASTS.

THEN...ON FRIDAY...MOISTURE WILL BEGIN TO INCREASE AND SHOWERS WILL
RETURN IN THE SOUTHEASTERLY FLOW...MAINLY TO NORTHWEST PUERTO RICO
AND NORTH OF THE CORDILLERA CENTRAL. SLIGHTLY DRIER DAYS WILL
BEGIN AGAIN ON SUNDAY AND LAST UNTIL WEDNESDAY OF NEXT WEEK AFTER
A TROUGH AT UPPER LEVELS PASSES SOUTH OF THE AREA AND BETTER
CONDITIONS ARE FOUND IN ITS NORTHEAST QUADRANT.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED THRU THE FCST PERIOD.
WINDS INCREASE TO 8-15 KTS FM THE EAST AFT 21/13Z WITH SEA BREEZE
VARIATIONS. VCSH PSBL AT TJSJ/TISX/TIST TIL EARLY IN THE
AFTERNOON. SHRA/TSRA ARE ONCE AGAIN EXPECTED ACROSS THE CENTRAL
MOUNTAIN RANGE OF PR BETWEEN 21/17-22Z CREATING BRIEF MVFR CONDS
AND MTN OBSCURATIONS... IMPACTING MAINLY TJMZ/TJBQ TAF SITES.

&&

.MARINE...GENERALLY DIMINISHING SEAS WILL PREVAIL THROUGH FRIDAY.
OVER THE WEEKEND WAVES FROM THE SOUTHEAST WILL INCREASE IN BOTH
THE CARIBBEAN AND ATLANTIC WATERS...BUT SMALL CRAFT ADVISORIES ARE
NOT EXPECTED THROUGH THE END OF THE MONTH.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  88  78  90  77 /  30  30  30  10
STT  88  79  88  79 /  20  30  30  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
COASTAL WATERS...NONE.
&&

$$

27/12






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