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000
FXCA62 TJSJ 021804
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
204 PM AST MON MAY 2 2016

.SYNOPSIS...MID TO UPPER LEVEL TROUGH WILL CONTINUE TO SLOWLY
LIFT EASTWARD ACROSS LOCAL REGION THROUGH TUESDAY.IN THE LOW
LEVELS...SURFACE HIGH PRESSURE CENTERED ACROSS THE NORTH CENTRAL
ATLANTIC WILL MAINTAIN A  MOIST SOUTHEAST WIND FLOW ACROSS THE
REGION THROUGH AT LEAST WEDNESDAY. WINDS ARE TO THEN BECOME MORE
SOUTHERLY DURING THE LATTER PART OF THE WORK WEEK AS THE ATLANTIC
HIGH BUILDS AND SINKS SOUTHWARD ACROSS THE CENTRAL ATLANTIC. THE
OVERALL WEATHER PATTERN WILL MAINTAIN AN MOIST AND UNSTABLE
ENVIRONMENT THROUGH THE MIDDLE OF THE WEEK.

&&

.DISCUSSION...FAVORABLE AND UNSTABLE CONDITIONS WILL CONTINUE
TODAY THROUGH EARLY WEDNESDAY AS PREVIOUSLY MENTIONED. FOR TODAY
EXPECT MOST ACTIVE AREAS TO BE FOCUSED ACROSS THE NORTHERN HALF
AND AND NORTHWESTERN SECTIONS OF PUERTO RICO RICO AS WELL AS OVER
ISOLATED AREAS IN THE U.S. VIRGIN ISLANDS DURING THE REST OF THE
AFTERNOON AND INTO THE EVENING HOURS. DUE TO SATURATED SOILS AND
UNSTABLE CONDITIONS...MINOR FLOODING OF URBAN AREAS AS WELL AS
QUICK RISES IN WATER LEVELS OF SOME RIVERS...SMALL STREAMS...AND
GUTS WILL REMAIN POSSIBLE FOR THE REST OF THE DAY OVER MUCH OF OF
THE ISLANDS. FOR THE NEXT FEW DAYS...THE MOIST SOUTHEAST FLOW AND
UNSTABLE CONDITIONS ALOFT WILL BE THE DRIVING FORCE OF ENHANCED
CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS AND COASTAL WATERS WITH
INCREASE POTENTIAL FOR MINOR FLOODING SITUATIONS.

BY WEDNESDAY...THE UPPER TROUGH IS TO FILL AND LIFT NORTHEAST AND
THE HIGH PRESSURE RIDGE IS FORECAST TO BUILD ALOFT ACROSS THE REGION
THROUGH THURSDAY.THIS CHANGE IN THE WEATHER PATTERN WILL LEAD TO A
DECREASE IN WIDESPREAD CONVECTION ACROSS THE ISLANDS. HOWEVER SUFFICIENT
LOW LEVEL MOISTURE CONVERGENCE COMBINED WITH LOCAL TERRAIN EFFECTS AND
DAYTIME HEATING WILL LEAD TO PERIODS OF SHOWER AND ISOLATED THUNDERSTORM
DEVELOPMENT MAINLY OVER PORTIONS THE CENTRAL AND NORTHWESTERN SECTIONS
OF PUERTO RICO. ISOLATED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ELSEWHERE.

BASED ON THE LATEST GFS MODEL GUIDANCE...THIS SHIFT IN THE WEATHER PATTERN
WILL BE SHORT LIVED AS A DEEP POLAR TROUGH WILL BECOME AMPLIFIED ACROSS
THE WESTERN ATLANTIC AND QUICKLY ERODE THE RIDGE BY LATE THURSDAY AND
IN TO THE UPCOMING WEEKEND. AS A RESULT A RETURN TO A MOIST AND UNSTABLE
WEATHER PATTERN IS AGAIN EXPECTED WITH GOOD POTENTIAL FOR PERIODS OF
STRONG CONVECTIVE DEVELOPMENT ACROSS THE COASTAL WATERS AND PORTIONS
OF THE INTERIOR AND NORTHERNHALF OF PUERTO RICO RICO. ALL IN ALL...THE
POTENTIAL FOR URBAN AND SMALL STREAM FLOODING WILL CONTINUE MOST OF
THE WEEK WITH THE STRONGEST ACTIVITY FOCUSED THE EAST AND SOUTHEAST
SECTIONS OF PUERTO RICO AND ON THE WINDWARD SIDE OF THE VIRGIN ISLANDS
DURING THE LATE EVENING AND EARLY MORNING HOURS. THE ACTIVITY IS TO
THEN SHIFT TO THE NORTH AND NORTHWESTERN SECTIONS OF PUERTO RICO DURING
THE AFTERNOON HOURS.

&&

.AVIATION...MOSTLY VFR COND WITH VCSH CAN BE EXPECTED ACROSS THE TAF
SITES. MOUNTAIN OBSC PSBL ACROSS THE INTERIOR AND WESTERN PR
UNTIL AROUND 02/22Z. THE SURFACE WINDS WILL CONTINUE FROM THE
SOUTH TO EAST-SOUTHEAST AT 10 TO 15 KNOTS WITH SEA BREEZE
VARIATIONS.

&&

.MARINE...OVERALL FAIRLY TRANQUIL SEAS EXPECTED OVERNIGHT .
HOWEVER...SHOWERS AND THUNDERSTORM DEVELOPMENT WILL CONTINUE
ACROSS THE LOCAL WATERS THROUGH TUESDAY. THIS WILL CONTINUE TO
CREATE HAZARDOUS MARINE CONDITIONS DUE TO LOCALLY HIGHER WAVES AND
WIND GUSTS NEAR THE STORMS. OTHERWISE...SEAS UP TO 5 FEET AND
WINDS UP TO 15 KNOTS ARE EXPECTED.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  75  87  75  87 /  30  30  20  20
STT  75  86  77  86 /  30  30  30  30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

05/09




000
FXCA62 TJSJ 021804
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
204 PM AST MON MAY 2 2016

.SYNOPSIS...MID TO UPPER LEVEL TROUGH WILL CONTINUE TO SLOWLY
LIFT EASTWARD ACROSS LOCAL REGION THROUGH TUESDAY.IN THE LOW
LEVELS...SURFACE HIGH PRESSURE CENTERED ACROSS THE NORTH CENTRAL
ATLANTIC WILL MAINTAIN A  MOIST SOUTHEAST WIND FLOW ACROSS THE
REGION THROUGH AT LEAST WEDNESDAY. WINDS ARE TO THEN BECOME MORE
SOUTHERLY DURING THE LATTER PART OF THE WORK WEEK AS THE ATLANTIC
HIGH BUILDS AND SINKS SOUTHWARD ACROSS THE CENTRAL ATLANTIC. THE
OVERALL WEATHER PATTERN WILL MAINTAIN AN MOIST AND UNSTABLE
ENVIRONMENT THROUGH THE MIDDLE OF THE WEEK.

&&

.DISCUSSION...FAVORABLE AND UNSTABLE CONDITIONS WILL CONTINUE
TODAY THROUGH EARLY WEDNESDAY AS PREVIOUSLY MENTIONED. FOR TODAY
EXPECT MOST ACTIVE AREAS TO BE FOCUSED ACROSS THE NORTHERN HALF
AND AND NORTHWESTERN SECTIONS OF PUERTO RICO RICO AS WELL AS OVER
ISOLATED AREAS IN THE U.S. VIRGIN ISLANDS DURING THE REST OF THE
AFTERNOON AND INTO THE EVENING HOURS. DUE TO SATURATED SOILS AND
UNSTABLE CONDITIONS...MINOR FLOODING OF URBAN AREAS AS WELL AS
QUICK RISES IN WATER LEVELS OF SOME RIVERS...SMALL STREAMS...AND
GUTS WILL REMAIN POSSIBLE FOR THE REST OF THE DAY OVER MUCH OF OF
THE ISLANDS. FOR THE NEXT FEW DAYS...THE MOIST SOUTHEAST FLOW AND
UNSTABLE CONDITIONS ALOFT WILL BE THE DRIVING FORCE OF ENHANCED
CONVECTIVE DEVELOPMENT ACROSS THE ISLANDS AND COASTAL WATERS WITH
INCREASE POTENTIAL FOR MINOR FLOODING SITUATIONS.

BY WEDNESDAY...THE UPPER TROUGH IS TO FILL AND LIFT NORTHEAST AND
THE HIGH PRESSURE RIDGE IS FORECAST TO BUILD ALOFT ACROSS THE REGION
THROUGH THURSDAY.THIS CHANGE IN THE WEATHER PATTERN WILL LEAD TO A
DECREASE IN WIDESPREAD CONVECTION ACROSS THE ISLANDS. HOWEVER SUFFICIENT
LOW LEVEL MOISTURE CONVERGENCE COMBINED WITH LOCAL TERRAIN EFFECTS AND
DAYTIME HEATING WILL LEAD TO PERIODS OF SHOWER AND ISOLATED THUNDERSTORM
DEVELOPMENT MAINLY OVER PORTIONS THE CENTRAL AND NORTHWESTERN SECTIONS
OF PUERTO RICO. ISOLATED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ELSEWHERE.

BASED ON THE LATEST GFS MODEL GUIDANCE...THIS SHIFT IN THE WEATHER PATTERN
WILL BE SHORT LIVED AS A DEEP POLAR TROUGH WILL BECOME AMPLIFIED ACROSS
THE WESTERN ATLANTIC AND QUICKLY ERODE THE RIDGE BY LATE THURSDAY AND
IN TO THE UPCOMING WEEKEND. AS A RESULT A RETURN TO A MOIST AND UNSTABLE
WEATHER PATTERN IS AGAIN EXPECTED WITH GOOD POTENTIAL FOR PERIODS OF
STRONG CONVECTIVE DEVELOPMENT ACROSS THE COASTAL WATERS AND PORTIONS
OF THE INTERIOR AND NORTHERNHALF OF PUERTO RICO RICO. ALL IN ALL...THE
POTENTIAL FOR URBAN AND SMALL STREAM FLOODING WILL CONTINUE MOST OF
THE WEEK WITH THE STRONGEST ACTIVITY FOCUSED THE EAST AND SOUTHEAST
SECTIONS OF PUERTO RICO AND ON THE WINDWARD SIDE OF THE VIRGIN ISLANDS
DURING THE LATE EVENING AND EARLY MORNING HOURS. THE ACTIVITY IS TO
THEN SHIFT TO THE NORTH AND NORTHWESTERN SECTIONS OF PUERTO RICO DURING
THE AFTERNOON HOURS.

&&

.AVIATION...MOSTLY VFR COND WITH VCSH CAN BE EXPECTED ACROSS THE TAF
SITES. MOUNTAIN OBSC PSBL ACROSS THE INTERIOR AND WESTERN PR
UNTIL AROUND 02/22Z. THE SURFACE WINDS WILL CONTINUE FROM THE
SOUTH TO EAST-SOUTHEAST AT 10 TO 15 KNOTS WITH SEA BREEZE
VARIATIONS.

&&

.MARINE...OVERALL FAIRLY TRANQUIL SEAS EXPECTED OVERNIGHT .
HOWEVER...SHOWERS AND THUNDERSTORM DEVELOPMENT WILL CONTINUE
ACROSS THE LOCAL WATERS THROUGH TUESDAY. THIS WILL CONTINUE TO
CREATE HAZARDOUS MARINE CONDITIONS DUE TO LOCALLY HIGHER WAVES AND
WIND GUSTS NEAR THE STORMS. OTHERWISE...SEAS UP TO 5 FEET AND
WINDS UP TO 15 KNOTS ARE EXPECTED.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  75  87  75  87 /  30  30  20  20
STT  75  86  77  86 /  30  30  30  30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

05/09




000
FXCA62 TJSJ 021405
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1005 AM AST MON MAY 2 2016

.UPDATE...SHOWERS WITH HEAVY RAIN CONTINUED TO AFFECT THE US
VIRGIN ISLANDS...ESPECIALLY SAINT JOHN AND SAINT THOMAS DURING THE
EARLY TO MID MORNING HOURS. SHOWERS ASSOCIATED WITH AN OUTFLOW
BOUNDARY MOVED INTO THE SOUTHERN COASTAL AREAS AROUND 8 AM...AND
CONTINUED FOR A FEW HOURS. ISOLATED SHOWERS ALSO BEGAN AFFECTING
THE NORTHEASTERN SECTIONS OF PUERTO RICO DURING THIS PERIOD.

SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED TO CONTINUE
THROUGHOUT THE LATE MORNING AND AFTERNOON HOURS MAINLY ACROSS THE
EASTERN HALF OF PUERTO RICO...AND THEN SPREAD INTO THE NORTH AND
NORTHWESTERN PORTIONS OF PUERTO RICO LATER THIS AFTERNOON. DUE TO
THE ALREADY SATURATED SOILS...ADDITIONAL RAINFALL MAY CAUSE URBAN
AND SMALL STREAM FLOODING ACROSS ISOLATED AREAS DURING THE
DAY...AND MAY ALSO EXPERIENCE PERIODS OF VERY HEAVY
RAINFALL...REDUCED VISIBILITY AND POSSIBLE LIGHTNING.

.AVIATION...PASSING SHRA AND VCTS CAN CONTINUE TO BE EXPECTED
MAINLY ACROSS TJSJ/TIST/TISX/TJPS/TNCM/TKPK DURING THE MORNING
AND EARLY AFT HRS. BASED ON THE 02/12Z SOUNDING...SURFACE WINDS
WILL CONTINUE FROM THE E-SE AT 10-15 KNOTS...WITH HIGHER GUSTS
POSSIBLE NEAR SHOWERS. REST OF THE FORECAST UNCHANGED.

.MARINE...SHOWER AND THUNDERSTORM DEVELOPMENT WILL CONTINUE
ACROSS THE LOCAL WATERS DURING THE FORECAST PERIOD...CREATING
HAZARDOUS MARINE CONDITIONS DUE TO LOCALLY HIGHER WAVES AND WIND
GUSTS NEAR THE STORMS. OTHERWISE...SEAS UP TO 5 FEET AND WINDS UP
TO 15 KNOTS ARE EXPECTED.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...AT UPPER LEVELS...A WEAK SHORT WAVE MOVED THROUGH THE
AREA OVERNIGHT AND ANOTHER IS EXPECTED TODAY AS WINDS RETURN TO
WEST SOUTHWEST UNTIL TUESDAY AFTERNOON. A BROAD RIDGE THEN PASSES
OVER ON WEDNESDAY NIGHT. THIS RIDGE MOVES INTO THE TROPICAL
ATLANTIC OVER THE WEEKEND. A STRONG LOW IS CURRENTLY PROGGED TO
MOVE INTO THE WESTERN ATLANTIC NEAR NEW JERSEY FRIDAY NIGHT MOVING
EAST AND ITS FRINGES SHOULD BEGIN AFFECTING THE LOCAL AREA
SATURDAY NIGHT OR SUNDAY.

AT MID LEVELS..WEAK TROUGHINESS EXTENDS INTO THE AREA FROM THE
NORTH THROUGH MID WEEK WHILE HIGH PRESSURE OCCUPIES MOST OF THE
CARIBBEAN. HIGH PRESSURE CONTINUES OVER THE CARIBBEAN THROUGH THE
WEEKEND AS THE LOW MOVES INTO THE WESTERN ATLANTIC NORTH OF THE
AREA SUNDAY AND MONDAY.

AT LOWER LEVELS...HIGH PRESSURE NORTH OF THE AREA AND IN THE
NORTHEAST ATLANTIC WILL CONSOLIDATE DURING THE MIDDLE OF THE WEEK
AND BUILD THROUGH FRIDAY OVER THE CENTRAL ATLANTIC. THIS WILL
MAINTAIN SOUTHEAST FLOW OVER THE LOCAL AREA WITH ABUNDANT MOISTURE
THROUGH AT LEAST MONDAY OF NEXT WEEK.

DISCUSSION...SHOWERS STAYED CLEAR OF THE FORECAST AREA FOR MUCH
OF THE NIGHT. BUT DURING THE PRE-DAWN HOURS...SHOWERS FROM THE
BAND OF MOISTURE TO OUR SOUTHEAST BEGAN MOVING INTO THE FORECAST
AREA EAST OF SAINT CROIX AND SOUTH OF VIEQUES AND SAINT CROIX. AT
5 AM AST SHOWERS WERE MOVING BETWEEN SAINT JOHN AND SAINT CROIX.
MODELS AGREE THAT SHOWERS WILL APPROACH THE AREA FROM THE
SOUTHEAST AGAIN TODAY...BUT THE GFS WAS MUCH TOO WET OVERNIGHT
PUTTING 60 TO 100 PERCENT POPS IN THE 02/06Z FORECAST IN VARIOUS
PLACES...MAINLY OVER WATER. SKIES ARE MOSTLY CLEAR OVER PUERTO
RICO AND THE U.S. VIRGIN ISLANDS AND THE EARLY PART OF THE MORNING
IS EXPECTED TO BE MOSTLY SUNNY WITH A RAPID WARM-UP. THEN CLOUDS
WILL FORM WITH SHOWERS OVER THE INTERIOR OF PUERTO RICO.
THUNDERSTORMS COULD BEGIN A EARLY AS 11 AM AST... BUT MOST WILL
WAIT TILL AFTERNOON.

TODAY IS A LITTLE DIFFERENT THAN YESTERDAY. THE BAND OF MOISTURE
IS A LITTLE FARTHER EAST AND WIND FLOW ALSO APPEARS TO BE A LITTLE
MORE EASTERLY. HOWEVER IN THE LOWEST 10 KFT THE GFS SHOWS THE
WIND VEERING FROM THE NORTHEAST AT 02/00Z TO EAST SOUTHEAST AT
02/18Z AND THIS SHOULD ALLOW SHOWERS AND THUNDERSTORMS TO VISIT
THE NORTHERN COASTAL PLAINS OF PUERTO RICO AS WELL AS THE
NORTHWEST CORNER OF THE ISLAND WITH THE POSSIBILITY OF A STREAMER
CROSSING SOUTHERN CAROLINA AND THE SAN JUAN BAY WITH HEAVY RAIN
DURING THE AFTERNOON. A SIMILAR PATTERN IS EXPECTED FOR TUESDAY
AND WEDNESDAY. THEN THURSDAY WINDS TURN MORE SOUTHERLY AND HEAVY
RAIN SHOWERS WILL FAVOR MORE OF THE NORTH COAST OF PUERTO RICO.
URBAN AND SMALL STREAM FLOODING SHOULD BE EXPECTED THIS WEEK
ACROSS A NUMBER OF AREAS MAINLY NORTH OF THE CORDILLERA CENTRAL.
MOS TENDS TO WARM UP CONSIDERABLY BEGINNING TOMORROW AND
STEEPENING THROUGH FRIDAY...BUT CLOUDS COULD KEEP IT FROM REACHING
THE LAST FEW DEGREES. NEVERTHELESS EXPECT SOME LOWER 90S BY FRIDAY
AS MENTIONED YESTERDAY.

MID LEVELS CONTINUE TO HAVE MODEST MOISTURE UNTIL DRIER AIR MOVES
IN SOMETIME NEXT WEEK. ALTHOUGH MODELS BRING IN A BULLS EYE OVER
STRONG DIVERGENCE IN THE THE UPPER LEVELS ON MOTHERS DAY THAT
WOULD APPEAR TO FAVOR STRONGER CONVECTION...IT IS STILL TOO FAR
OUT TO PLACE ANY CONFIDENCE IN HEAVY RAIN FOR THE WEEKEND.
NEVERTHELESS THE SITUATION BEARS MONITORING.

AVIATION...PASSING SHRA AND VCTS CAN BE EXPECTED MAINLY ACROSS
TIST/TISX/TJPS/TNCM/TKPK DURING THE MORNING HOURS. MOUNTAIN
OBSCURATIONS ACROSS THE INTERIOR AND WESTERN PR WITH TSRA/SHRA
AFT 02/16Z. AS A RESULT...EXPECT BKN CEILING AT FL025-FL060 AT
TJBQ/TJMZ/TJPS AND POSSIBLY AT TJSJ. THE SURFACE WINDS WILL
CONTINUE FROM THE SOUTH TO EAST-SOUTHEAST AT 10 TO 15 KNOTS WITH
SEA BREEZE VARIATIONS AFT 02/13Z.

MARINE...SEAS WILL PEAK AT AROUND 4.5 FEET ON TUESDAY NIGHT...BUT
IT IS MOSTLY EASTERLY WIND WAVES WITH LITTLE NORTHERLY SWELL. SEAS
THEN SUBSIDE UNTIL THURSDAY. NO SMALL CRAFT ADVISORIES ARE
EXPECTED THROUGH THE WEEKEND IN ANY LOCAL WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  85  75  87  75 /  60  30  30  20
STT  85  75  86  77 /  50  30  20  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

ACP/RAM




000
FXCA62 TJSJ 020936
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
536 AM AST MON MAY 2 2016

.SYNOPSIS...AT UPPER LEVELS...A WEAK SHORT WAVE MOVED THROUGH THE
AREA OVERNIGHT AND ANOTHER IS EXPECTED TODAY AS WINDS RETURN TO
WEST SOUTHWEST UNTIL TUESDAY AFTERNOON. A BROAD RIDGE THEN PASSES
OVER ON WEDNESDAY NIGHT. THIS RIDGE MOVES INTO THE TROPICAL
ATLANTIC OVER THE WEEKEND. A STRONG LOW IS CURRENTLY PROGGED TO
MOVE INTO THE WESTERN ATLANTIC NEAR NEW JERSEY FRIDAY NIGHT MOVING
EAST AND ITS FRINGES SHOULD BEGIN AFFECTING THE LOCAL AREA
SATURDAY NIGHT OR SUNDAY.

AT MID LEVELS..WEAK TROUGHINESS EXTENDS INTO THE AREA FROM THE
NORTH THROUGH MID WEEK WHILE HIGH PRESSURE OCCUPIES MOST OF THE
CARIBBEAN. HIGH PRESSURE CONTINUES OVER THE CARIBBEAN THROUGH THE
WEEKEND AS THE LOW MOVES INTO THE WESTERN ATLANTIC NORTH OF THE
AREA SUNDAY AND MONDAY.

AT LOWER LEVELS...HIGH PRESSURE NORTH OF THE AREA AND IN THE
NORTHEAST ATLANTIC WILL CONSOLIDATE DURING THE MIDDLE OF THE WEEK
AND BUILD THROUGH FRIDAY OVER THE CENTRAL ATLANTIC. THIS WILL
MAINTAIN SOUTHEAST FLOW OVER THE LOCAL AREA WITH ABUNDANT MOISTURE
THROUGH AT LEAST MONDAY OF NEXT WEEK.

&&

.DISCUSSION...SHOWERS STAYED CLEAR OF THE FORECAST AREA FOR MUCH
OF THE NIGHT. BUT DURING THE PRE-DAWN HOURS...SHOWERS FROM THE
BAND OF MOISTURE TO OUR SOUTHEAST BEGAN MOVING INTO THE FORECAST
AREA EAST OF SAINT CROIX AND SOUTH OF VIEQUES AND SAINT CROIX. AT
5 AM AST SHOWERS WERE MOVING BETWEEN SAINT JOHN AND SAINT CROIX.
MODELS AGREE THAT SHOWERS WILL APPROACH THE AREA FROM THE
SOUTHEAST AGAIN TODAY...BUT THE GFS WAS MUCH TOO WET OVERNIGHT
PUTTING 60 TO 100 PERCENT POPS IN THE 02/06Z FORECAST IN VARIOUS
PLACES...MAINLY OVER WATER. SKIES ARE MOSTLY CLEAR OVER PUERTO
RICO AND THE U.S. VIRGIN ISLANDS AND THE EARLY PART OF THE MORNING
IS EXPECTED TO BE MOSTLY SUNNY WITH A RAPID WARM-UP. THEN CLOUDS
WILL FORM WITH SHOWERS OVER THE INTERIOR OF PUERTO RICO.
THUNDERSTORMS COULD BEGIN A EARLY AS 11 AM AST... BUT MOST WILL
WAIT TILL AFTERNOON.

TODAY IS A LITTLE DIFFERENT THAN YESTERDAY. THE BAND OF MOISTURE
IS A LITTLE FARTHER EAST AND WIND FLOW ALSO APPEARS TO BE A LITTLE
MORE EASTERLY. HOWEVER IN THE LOWEST 10 KFT THE GFS SHOWS THE
WIND VEERING FROM THE NORTHEAST AT 02/00Z TO EAST SOUTHEAST AT
02/18Z AND THIS SHOULD ALLOW SHOWERS AND THUNDERSTORMS TO VISIT
THE NORTHERN COASTAL PLAINS OF PUERTO RICO AS WELL AS THE
NORTHWEST CORNER OF THE ISLAND WITH THE POSSIBILITY OF A STREAMER
CROSSING SOUTHERN CAROLINA AND THE SAN JUAN BAY WITH HEAVY RAIN
DURING THE AFTERNOON. A SIMILAR PATTERN IS EXPECTED FOR TUESDAY
AND WEDNESDAY. THEN THURSDAY WINDS TURN MORE SOUTHERLY AND HEAVY
RAIN SHOWERS WILL FAVOR MORE OF THE NORTH COAST OF PUERTO RICO.
URBAN AND SMALL STREAM FLOODING SHOULD BE EXPECTED THIS WEEK
ACROSS A NUMBER OF AREAS MAINLY NORTH OF THE CORDILLERA CENTRAL.
MOS TENDS TO WARM UP CONSIDERABLY BEGINNING TOMORROW AND
STEEPENING THROUGH FRIDAY...BUT CLOUDS COULD KEEP IT FROM REACHING
THE LAST FEW DEGREES. NEVERTHELESS EXPECT SOME LOWER 90S BY FRIDAY
AS MENTIONED YESTERDAY.

MID LEVELS CONTINUE TO HAVE MODEST MOISTURE UNTIL DRIER AIR MOVES
IN SOMETIME NEXT WEEK. ALTHOUGH MODELS BRING IN A BULLS EYE OVER
STRONG DIVERGENCE IN THE THE UPPER LEVELS ON MOTHERS DAY THAT
WOULD APPEAR TO FAVOR STRONGER CONVECTION...IT IS STILL TOO FAR
OUT TO PLACE ANY CONFIDENCE IN HEAVY RAIN FOR THE WEEKEND.
NEVERTHELESS THE SITUATION BEARS MONITORING.

&&

.AVIATION...PASSING SHRA AND VCTS CAN BE EXPECTED MAINLY ACROSS
TIST/TISX/TJPS/TNCM/TKPK DURING THE MORNING HOURS. MOUNTAIN
OBSCURATIONS ACROSS THE INTERIOR AND WESTERN PR WITH TSRA/SHRA
AFT 02/16Z. AS A RESULT...EXPECT BKN CEILING AT FL025-FL060 AT
TJBQ/TJMZ/TJPS AND POSSIBLY AT TJSJ. THE SURFACE WINDS WILL
CONTINUE FROM THE SOUTH TO EAST-SOUTHEAST AT 10 TO 15 KNOTS WITH
SEA BREEZE VARIATIONS AFT 02/13Z.

&&

.MARINE...SEAS WILL PEAK AT AROUND 4.5 FEET ON TUESDAY NIGHT...BUT
IT IS MOSTLY EASTERLY WIND WAVES WITH LITTLE NORTHERLY SWELL. SEAS
THEN SUBSIDE UNTIL THURSDAY. NO SMALL CRAFT ADVISORIES ARE
EXPECTED THROUGH THE WEEKEND IN ANY LOCAL WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  85  75  87  75 /  60  30  30  20
STT  85  75  86  77 /  50  30  20  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

27/12




000
FXCA62 TJSJ 020936
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
536 AM AST MON MAY 2 2016

.SYNOPSIS...AT UPPER LEVELS...A WEAK SHORT WAVE MOVED THROUGH THE
AREA OVERNIGHT AND ANOTHER IS EXPECTED TODAY AS WINDS RETURN TO
WEST SOUTHWEST UNTIL TUESDAY AFTERNOON. A BROAD RIDGE THEN PASSES
OVER ON WEDNESDAY NIGHT. THIS RIDGE MOVES INTO THE TROPICAL
ATLANTIC OVER THE WEEKEND. A STRONG LOW IS CURRENTLY PROGGED TO
MOVE INTO THE WESTERN ATLANTIC NEAR NEW JERSEY FRIDAY NIGHT MOVING
EAST AND ITS FRINGES SHOULD BEGIN AFFECTING THE LOCAL AREA
SATURDAY NIGHT OR SUNDAY.

AT MID LEVELS..WEAK TROUGHINESS EXTENDS INTO THE AREA FROM THE
NORTH THROUGH MID WEEK WHILE HIGH PRESSURE OCCUPIES MOST OF THE
CARIBBEAN. HIGH PRESSURE CONTINUES OVER THE CARIBBEAN THROUGH THE
WEEKEND AS THE LOW MOVES INTO THE WESTERN ATLANTIC NORTH OF THE
AREA SUNDAY AND MONDAY.

AT LOWER LEVELS...HIGH PRESSURE NORTH OF THE AREA AND IN THE
NORTHEAST ATLANTIC WILL CONSOLIDATE DURING THE MIDDLE OF THE WEEK
AND BUILD THROUGH FRIDAY OVER THE CENTRAL ATLANTIC. THIS WILL
MAINTAIN SOUTHEAST FLOW OVER THE LOCAL AREA WITH ABUNDANT MOISTURE
THROUGH AT LEAST MONDAY OF NEXT WEEK.

&&

.DISCUSSION...SHOWERS STAYED CLEAR OF THE FORECAST AREA FOR MUCH
OF THE NIGHT. BUT DURING THE PRE-DAWN HOURS...SHOWERS FROM THE
BAND OF MOISTURE TO OUR SOUTHEAST BEGAN MOVING INTO THE FORECAST
AREA EAST OF SAINT CROIX AND SOUTH OF VIEQUES AND SAINT CROIX. AT
5 AM AST SHOWERS WERE MOVING BETWEEN SAINT JOHN AND SAINT CROIX.
MODELS AGREE THAT SHOWERS WILL APPROACH THE AREA FROM THE
SOUTHEAST AGAIN TODAY...BUT THE GFS WAS MUCH TOO WET OVERNIGHT
PUTTING 60 TO 100 PERCENT POPS IN THE 02/06Z FORECAST IN VARIOUS
PLACES...MAINLY OVER WATER. SKIES ARE MOSTLY CLEAR OVER PUERTO
RICO AND THE U.S. VIRGIN ISLANDS AND THE EARLY PART OF THE MORNING
IS EXPECTED TO BE MOSTLY SUNNY WITH A RAPID WARM-UP. THEN CLOUDS
WILL FORM WITH SHOWERS OVER THE INTERIOR OF PUERTO RICO.
THUNDERSTORMS COULD BEGIN A EARLY AS 11 AM AST... BUT MOST WILL
WAIT TILL AFTERNOON.

TODAY IS A LITTLE DIFFERENT THAN YESTERDAY. THE BAND OF MOISTURE
IS A LITTLE FARTHER EAST AND WIND FLOW ALSO APPEARS TO BE A LITTLE
MORE EASTERLY. HOWEVER IN THE LOWEST 10 KFT THE GFS SHOWS THE
WIND VEERING FROM THE NORTHEAST AT 02/00Z TO EAST SOUTHEAST AT
02/18Z AND THIS SHOULD ALLOW SHOWERS AND THUNDERSTORMS TO VISIT
THE NORTHERN COASTAL PLAINS OF PUERTO RICO AS WELL AS THE
NORTHWEST CORNER OF THE ISLAND WITH THE POSSIBILITY OF A STREAMER
CROSSING SOUTHERN CAROLINA AND THE SAN JUAN BAY WITH HEAVY RAIN
DURING THE AFTERNOON. A SIMILAR PATTERN IS EXPECTED FOR TUESDAY
AND WEDNESDAY. THEN THURSDAY WINDS TURN MORE SOUTHERLY AND HEAVY
RAIN SHOWERS WILL FAVOR MORE OF THE NORTH COAST OF PUERTO RICO.
URBAN AND SMALL STREAM FLOODING SHOULD BE EXPECTED THIS WEEK
ACROSS A NUMBER OF AREAS MAINLY NORTH OF THE CORDILLERA CENTRAL.
MOS TENDS TO WARM UP CONSIDERABLY BEGINNING TOMORROW AND
STEEPENING THROUGH FRIDAY...BUT CLOUDS COULD KEEP IT FROM REACHING
THE LAST FEW DEGREES. NEVERTHELESS EXPECT SOME LOWER 90S BY FRIDAY
AS MENTIONED YESTERDAY.

MID LEVELS CONTINUE TO HAVE MODEST MOISTURE UNTIL DRIER AIR MOVES
IN SOMETIME NEXT WEEK. ALTHOUGH MODELS BRING IN A BULLS EYE OVER
STRONG DIVERGENCE IN THE THE UPPER LEVELS ON MOTHERS DAY THAT
WOULD APPEAR TO FAVOR STRONGER CONVECTION...IT IS STILL TOO FAR
OUT TO PLACE ANY CONFIDENCE IN HEAVY RAIN FOR THE WEEKEND.
NEVERTHELESS THE SITUATION BEARS MONITORING.

&&

.AVIATION...PASSING SHRA AND VCTS CAN BE EXPECTED MAINLY ACROSS
TIST/TISX/TJPS/TNCM/TKPK DURING THE MORNING HOURS. MOUNTAIN
OBSCURATIONS ACROSS THE INTERIOR AND WESTERN PR WITH TSRA/SHRA
AFT 02/16Z. AS A RESULT...EXPECT BKN CEILING AT FL025-FL060 AT
TJBQ/TJMZ/TJPS AND POSSIBLY AT TJSJ. THE SURFACE WINDS WILL
CONTINUE FROM THE SOUTH TO EAST-SOUTHEAST AT 10 TO 15 KNOTS WITH
SEA BREEZE VARIATIONS AFT 02/13Z.

&&

.MARINE...SEAS WILL PEAK AT AROUND 4.5 FEET ON TUESDAY NIGHT...BUT
IT IS MOSTLY EASTERLY WIND WAVES WITH LITTLE NORTHERLY SWELL. SEAS
THEN SUBSIDE UNTIL THURSDAY. NO SMALL CRAFT ADVISORIES ARE
EXPECTED THROUGH THE WEEKEND IN ANY LOCAL WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  85  75  87  75 /  60  30  30  20
STT  85  75  86  77 /  50  30  20  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

27/12




000
FXCA62 TJSJ 020158
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
958 PM AST SUN MAY 1 2016

.UPDATE...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WERE
OBSERVED IN THE AFTERNOON HOURS ACROSS MUCH OF ST. CROIX AND THE
EASTERN...INTERIOR AND WESTERN SECTIONS OF PR. SOME OF THESE
THUNDERSTORMS CREATED HEAVY DOWNPOURS AT TIMES THAT LED TO URBAN
AND SMALL STREAM FLOODING. ESPECIALLY ALONG THE SOUTHEASTERN COAST
OF PR AND ACROSS SECTIONS OF INTERIOR PR. THE DOPPLER RADAR
ESTIMATED ANYWHERE BETWEEN 2-3 INCHES OF RAIN WITH THE HEAVIEST
SHOWERS. FOR THE REST OF THE OVERNIGHT INTO THE EARLY MORNING
HOURS...SHOWERS CAN STILL AFFECT THE USVI AND SOUTH/SOUTHEASTERN
SECTIONS OF PR. MINOR CHANGES MADE TO SHORT TERM WIND GRIDS.
LATEST 02/00Z TJSJ UPPER AIR SOUNDING CONTINUES TO INDICATE A
STEADY TREND SINCE LAST NIGHT OF AROUND 1.75 INCHES OF PWAT AND
LOW LEVEL SOUTHEASTERLY WINDS AROUND 15-25 KTS.


&&


.AVIATION UPDATE...MAINLY VFR CONDITIONS WILL PREVAIL ACROSS ALL TAF SITES
OVERNIGHT. SOME LIGHT PASSING SHOWERS ARE EXPECTED OVER TNCM AND
TKPK THROUGH AT LEAST 02/12Z. LOW LEVEL WINDS WILL BE LIGHT AND
VARIABLE.


&&

.MARINE UPDATE...NOT MUCH HAS CHANGED...BUOYS ACROSS PR AND THE
USVI ARE INDICATING SEAS BETWEEN 2 TO 4 FEET AND SOUTH-SOUTHEAST
WINDS AROUND 10 KNOTS. SEAS SHOULD CONTINUE BELOW SMALL CRAFT
ADVISORY CRITERIA FOR THE NEXT SEVERAL DAYS.


&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...UPPER LEVEL TROUGH LOCATED OVER PUERTO RICO
HAS BEEN ENHANCING THE INSTABILITY AND MOISTURE TRANSPORT
OVER PUERTO RICO AND THE U.S. VIRGIN ISLANDS DURING THE
WEEKEND. THE TROUGH ALOFT WILL WEAKEN THROUGH MIDWEEK.
ALTHOUGH...A RELATIVELY UNSTABLE PATTERN WILL PERSIST
MOST OF THE WEEK...DRIER AIR AT MID LEVELS WILL LIMIT
THE COVERAGE OF THE SHOWER AND THUNDERSTORM ACTIVITY.

DISCUSSION...HIGH CONVECTIVE INSTABILITY ASSOCIATED WITH
AN UPPER TROUGH OVER PUERTO RICO HAS RESULTED IN THE DEVELOPMENT
SHOWERS AND ISOLATED STRONG THUNDERSTORMS OVER MOST OF THE
FORECAST AREA. INTENSE RAINFALL WAS OBSERVED THIS MORNING
OVER PORTIONS OF THE WEST AND EAST THIRD OF PR. RAINFALL
ACCUMULATIONS OF 1-3 INCHES WERE ESTIMATED BY THE DOPPLER RADAR
ACROSS THE WEST...WESTERN INTERIOR AND NORTHEAST PR.

OPERATIONAL MODELS NOW SUGGEST THAT THE WEATHER CONDITIONS
WILL IMPROVE GRADUALLY THROUGH THURSDAY. AS UPPER TROUGH
WEAKENS AND DRIER AIR WILL FILTER IN AT MID LEVELS...THE
CONVECTIVE INSTABILITY WILL LIKELY DECREASE OVER THE LOCAL
AREA. ALTHOUGH...SHOWERS AND THUNDERSTORMS ARE STILL EXPECTED
OVER PORTIONS OF THE INTERIOR...NORTH AND NORTHWEST PR EACH
AFTERNOON...THE SHOWER AND THUNDERSTORM COVERAGE WILL DECREASE
THROUGH AT LEAST MIDWEEK. MAX TEMPERATURES WILL INCREASE SOMEWHAT
ACROSS THE LOCAL ISLANDS AS SOUTHEASTERLY FLOW AND LESS CLOUDINESS
ARE EXPECTED OVER THE NEXT COUPLE OF DAYS. MAX TEMPS WILL RANGE
FROM THE UPPER 80S TO LOW 90S...ESPECIALLY ALONG THE NORTH
COASTAL PLAINS.

AVIATION...PERIODS OF MVFR CONDS OR EVEN IFR CONDS WILL REMAIN
POSSIBLE AT THE USVI TERMINALS AS WELL AS JBQ/JMZ/JSJ IN SHRA/TSRA
DEVELOPMENT THROUGH ABOUT 01/22Z. ELSEWHERE...MAINLY VFR CONDS.
AFTER 01/22Z...VCSH IN AND AROUND THE LEEWARD...USVI AND JSJ
TERMINALS. SOUTHEAST WINDS AT 5 TO 10 KT...BECOMING LIGHT AND
VARIABLE OVERNIGHT.

MARINE...WINDS OF 5 TO 15 KNOTS AND SEAS OF 3 TO 5 FEET
RESPECTIVELY. MAIN HAZARD FOR MARINERS TODAY IS THE THUNDERSTORMS
OVER THE REGIONAL WATERS...ESPECIALLY NEAR USVI...AND NORTHEAST
PUERTO RICO. NO SMALL CRAFT ADVISORIES ARE ANTICIPATED OVER THE
NEXT 5-7 DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  88  76  88 /  30  30  40  30
STT  78  87  76  87 /  50  50  50  30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

71/13




000
FXCA62 TJSJ 011806
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
206 PM AST SUN MAY 1 2016

.SYNOPSIS...UPPER LEVEL TROUGH LOCATED OVER PUERTO RICO
HAS BEEN ENHANCING THE INSTABILITY AND MOISTURE TRANSPORT
OVER PUERTO RICO AND THE U.S. VIRGIN ISLANDS DURING THE
WEEKEND. THE TROUGH ALOFT WILL WEAKEN THROUGH MIDWEEK.
ALTHOUGH...A RELATIVELY UNSTABLE PATTERN WILL PERSIST
MOST OF THE WEEK...DRIER AIR AT MID LEVELS WILL LIMIT
THE COVERAGE OF THE SHOWER AND THUNDERSTORM ACTIVITY.

&&

.DISCUSSION...HIGH CONVECTIVE INSTABILITY ASSOCIATED WITH
AN UPPER TROUGH OVER PUERTO RICO HAS RESULTED IN THE DEVELOPMENT
SHOWERS AND ISOLATED STRONG THUNDERSTORMS OVER MOST OF THE
FORECAST AREA. INTENSE RAINFALL WAS OBSERVED THIS MORNING
OVER PORTIONS OF THE WEST AND EAST THIRD OF PR. RAINFALL
ACCUMULATIONS OF 1-3 INCHES WERE ESTIMATED BY THE DOPPLER RADAR
ACROSS THE WEST...WESTERN INTERIOR AND NORTHEAST PR.

OPERATIONAL MODELS NOW SUGGEST THAT THE WEATHER CONDITIONS
WILL IMPROVE GRADUALLY THROUGH THURSDAY. AS UPPER TROUGH
WEAKENS AND DRIER AIR WILL FILTER IN AT MID LEVELS...THE
CONVECTIVE INSTABILITY WILL LIKELY DECREASE OVER THE LOCAL
AREA. ALTHOUGH...SHOWERS AND THUNDERSTORMS ARE STILL EXPECTED
OVER PORTIONS OF THE INTERIOR...NORTH AND NORTHWEST PR EACH
AFTERNOON...THE SHOWER AND THUNDERSTORM COVERAGE WILL DECREASE
THROUGH AT LEAST MIDWEEK. MAX TEMPERATURES WILL INCREASE SOMEWHAT
ACROSS THE LOCAL ISLANDS AS SOUTHEASTERLY FLOW AND LESS CLOUDINESS
ARE EXPECTED OVER THE NEXT COUPLE OF DAYS. MAX TEMPS WILL RANGE
FROM THE UPPER 80S TO LOW 90S...ESPECIALLY ALONG THE NORTH
COASTAL PLAINS.

&&

.AVIATION...PERIODS OF MVFR CONDS OR EVEN IFR CONDS WILL REMAIN
POSSIBLE AT THE USVI TERMINALS AS WELL AS JBQ/JMZ/JSJ IN SHRA/TSRA
DEVELOPMENT THROUGH ABOUT 01/22Z. ELSEWHERE...MAINLY VFR CONDS.
AFTER 01/22Z...VCSH IN AND AROUND THE LEEWARD...USVI AND JSJ
TERMINALS. SOUTHEAST WINDS AT 5 TO 10 KT...BECOMING LIGHT AND
VARIABLE OVERNIGHT.

&&

.MARINE...WINDS OF 5 TO 15 KNOTS AND SEAS OF 3 TO 5 FEET
RESPECTIVELY. MAIN HAZARD FOR MARINERS TODAY IS THE THUNDERSTORMS
OVER THE REGIONAL WATERS...ESPECIALLY NEAR USVI...AND NORTHEAST
PUERTO RICO. NO SMALL CRAFT ADVISORIES ARE ANTICIPATED OVER THE
NEXT 5-7 DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  88  76  88 /  30  30  40  30
STT  78  87  76  87 /  50  50  50  30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

23/11




000
FXCA62 TJSJ 011806
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
206 PM AST SUN MAY 1 2016

.SYNOPSIS...UPPER LEVEL TROUGH LOCATED OVER PUERTO RICO
HAS BEEN ENHANCING THE INSTABILITY AND MOISTURE TRANSPORT
OVER PUERTO RICO AND THE U.S. VIRGIN ISLANDS DURING THE
WEEKEND. THE TROUGH ALOFT WILL WEAKEN THROUGH MIDWEEK.
ALTHOUGH...A RELATIVELY UNSTABLE PATTERN WILL PERSIST
MOST OF THE WEEK...DRIER AIR AT MID LEVELS WILL LIMIT
THE COVERAGE OF THE SHOWER AND THUNDERSTORM ACTIVITY.

&&

.DISCUSSION...HIGH CONVECTIVE INSTABILITY ASSOCIATED WITH
AN UPPER TROUGH OVER PUERTO RICO HAS RESULTED IN THE DEVELOPMENT
SHOWERS AND ISOLATED STRONG THUNDERSTORMS OVER MOST OF THE
FORECAST AREA. INTENSE RAINFALL WAS OBSERVED THIS MORNING
OVER PORTIONS OF THE WEST AND EAST THIRD OF PR. RAINFALL
ACCUMULATIONS OF 1-3 INCHES WERE ESTIMATED BY THE DOPPLER RADAR
ACROSS THE WEST...WESTERN INTERIOR AND NORTHEAST PR.

OPERATIONAL MODELS NOW SUGGEST THAT THE WEATHER CONDITIONS
WILL IMPROVE GRADUALLY THROUGH THURSDAY. AS UPPER TROUGH
WEAKENS AND DRIER AIR WILL FILTER IN AT MID LEVELS...THE
CONVECTIVE INSTABILITY WILL LIKELY DECREASE OVER THE LOCAL
AREA. ALTHOUGH...SHOWERS AND THUNDERSTORMS ARE STILL EXPECTED
OVER PORTIONS OF THE INTERIOR...NORTH AND NORTHWEST PR EACH
AFTERNOON...THE SHOWER AND THUNDERSTORM COVERAGE WILL DECREASE
THROUGH AT LEAST MIDWEEK. MAX TEMPERATURES WILL INCREASE SOMEWHAT
ACROSS THE LOCAL ISLANDS AS SOUTHEASTERLY FLOW AND LESS CLOUDINESS
ARE EXPECTED OVER THE NEXT COUPLE OF DAYS. MAX TEMPS WILL RANGE
FROM THE UPPER 80S TO LOW 90S...ESPECIALLY ALONG THE NORTH
COASTAL PLAINS.

&&

.AVIATION...PERIODS OF MVFR CONDS OR EVEN IFR CONDS WILL REMAIN
POSSIBLE AT THE USVI TERMINALS AS WELL AS JBQ/JMZ/JSJ IN SHRA/TSRA
DEVELOPMENT THROUGH ABOUT 01/22Z. ELSEWHERE...MAINLY VFR CONDS.
AFTER 01/22Z...VCSH IN AND AROUND THE LEEWARD...USVI AND JSJ
TERMINALS. SOUTHEAST WINDS AT 5 TO 10 KT...BECOMING LIGHT AND
VARIABLE OVERNIGHT.

&&

.MARINE...WINDS OF 5 TO 15 KNOTS AND SEAS OF 3 TO 5 FEET
RESPECTIVELY. MAIN HAZARD FOR MARINERS TODAY IS THE THUNDERSTORMS
OVER THE REGIONAL WATERS...ESPECIALLY NEAR USVI...AND NORTHEAST
PUERTO RICO. NO SMALL CRAFT ADVISORIES ARE ANTICIPATED OVER THE
NEXT 5-7 DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  88  76  88 /  30  30  40  30
STT  78  87  76  87 /  50  50  50  30

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

23/11




000
FXCA62 TJSJ 011534
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1134 AM AST SUN MAY 1 2016

.UPDATE...SHORT TERM GRIDS WERE ADJUSTED TO MATCH CURRENT CONDITIONS.
TROUGH ALOFT...ACROSS THE WESTERN ATLANTIC TO THE NORTHERN CARIBBEAN
ISLES WILL CONTINUE TO MAINTAIN A DIVERGENT PATTERN...WITH PERTURBATIONS
STREAMING MOVING OVER THE ISLANDS FROM TIME TO TIME. AT LOWER LEVELS...
A WARM/MOIST ADVECTIVE PATTERN CONTINUES. THEREFORE...UNSTABLE AND
WET WEATHER CONDITIONS WILL CONTINUE TO PREVAIL ACROSS THE LOCAL
ISLANDS THROUGH AT LEAST EARLY THIS WEEK WITH PERIODS OF HEAVY
RAIN EXPECTED DURING THE AFTERNOON HOURS OVER AND NORTH OF THE
CORDILLERA. DUE TO ALREADY SATURATED SOILS...HEAVY RAINS COULD
LEAD TO FLOODING.

&&

.AVIATION...PERIODS OF MVFR CONDS OR EVEN IFR CONDS WILL REMAIN
POSSIBLE AT THE USVI TERMINALS AS WELL AS JBQ/JMZ/JSJ IN SHRA/TSRA
DEVELOPMENT THROUGH ABOUT 01/22Z. ELSEWHERE...MAINLY VFR CONDS.
AFTER 01/22Z...VCSH IN AND AROUND THE LEEWARD...USVI AND JSJ
TERMINALS. SOUTHEAST WINDS AT 5 TO 10 KT...BECOMING LIGHT AND
VARIABLE OVERNIGHT.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION. TRANQUIL MARINE
CONDITIONS EXPECTED ACROSS THE LOCAL WATERS...WITH SEAS AND
WINDS LOCALLY HIGHER IN THUNDERSTORMS.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...A TROUGH WITH A WEAK CUT-OFF LOW WILL PASS THROUGH
THE AREA TODAY. A SECONDS WEAKER TROUGH WILL PASS THROUGH ON
TUESDAY TO PROLONG THE TIME THE TROUGH STAYS IN PLACE. BY THURSDAY
A RIDGE WILL BEGIN TO BUILD OVER THE AREA...MOVING OVER THE
LEEWARD ISLANDS BY LATE IN THE WEEK.

AT MID LEVELS...CONSIDERABLE DRYING WILL TAKE PLACE TODAY AND ONLY
MODEST MOISTURE WILL PERSIST THROUGH THE END OF THE WEEK. WEAK
TROUGHINESS WILL PERSIST OVER THE AREA THROUGH MID WEEK...THEN
HIGH PRESSURE WILL BUILD INTO THE CENTRAL ATLANTIC AND OVER THE
CARIBBEAN SEA.

AT LOWER LEVELS...HIGH PRESSURE ENTERING THE WESTERN ATLANTIC AND
BUILDING INTO THE CENTRAL ATLANTIC WILL MAINTAIN SOUTHEAST TRADE
WIND FLOW THROUGH THE REST OF THE WEEK. ABUNDANT MOISTURE WILL
INCREASE OVER THE AREA AFTER MONDAY KEEPING SHOWERS AND
THUNDERSTORMS IN THE FORECAST.

DISCUSSION...SHOWERS AND THUNDERSTORMS HAD CLEARED OFF ALL BUT
THE SOUTHEAST PORTION OF THE FORECAST AREA BY LATE EVENING. BUT
THE LINE OF SHOWERS RETURNED AND NOW STRETCHES ACROSS THE
CARIBBEAN WATERS WITH SCATTERED SHOWERS. SHOWERS WENT OVER SAINT
CROIX AROUND 4 AM AST BUT THE HEAVIEST SHOWERS WENT AROUND THE
RAIN GAGE AT THE AIRPORT IN FREDERIKSTED. SHOWERS ARE WEAKENING AS
THEY APPROACH SAINT JOHN...SAINT THOMAS AND PUERTO RICO...BUT A
FEW ARE EXPECTED TO ARRIVE BY 8 AM AST. WITH SKIES CLEARING
HEATING SHOULD MAKE THINGS UNSTABLE AGAIN AND SHOWERS AND
THUNDERSTORMS WILL DEVELOP OVER PUERTO RICO. MODELS BARELY SHOW
THE AREA WHERE SHOWERS ARE FIRING OFF NOW...BUT RATHER SHOW A
WIDE AREA OF MOISTURE WITH LITTLE FORM...MAKING THE FORECAST
PARTICULARLY DIFFICULT TODAY. HOWEVER THE GFS BRINGS SOME
DIVERGENCE AT UPPER LEVELS ACROSS THE CENTER OF PUERTO RICO TODAY
FROM THE SOUTHWEST WHICH SHOULD HELP CONVECTION. OTHERWISE EXPECT
THE CONVECTION TO REMAIN MAINLY SOUTH AND EAST OF PUERTO RICO AND
POSSIBLY OVER THE U.S. VIRGIN ISLANDS. WINDS CONTINUE FROM THE
SOUTHEAST AND EXPECT WARMER TEMPERATURES TODAY. MOISTURE REACHES A
MINIMUM OVERNIGHT TONIGHT...BUT STILL AROUND 1.5 INCHES OF
PRECIPITABLE WATER. THEN OVER THE WEEK IT GRADUALLY RISES TO TWO
INCHES AGAIN. THE MODEL ALSO HAS 1000-850 MB THICKNESSES RISING
OVER THE AREA WITH THE WARMEST PERIOD FRIDAY THROUGH SUNDAY.
BECAUSE MOISTURE RISES THROUGH THE WEEK...THE FORECAST CAPE AND
LIFTED INDEX ALSO SHOW MORE INSTABILITY AS THE WEEK CONTINUES. THE
ONLY AMELIORATING FACTOR IS THAT MID LEVEL MOISTURE REMAINS MODEST
THROUGHOUT THE PERIOD...SO THE FLOODING POTENTIAL SHOULD REMAIN
LOCALIZED TO URBAN AND SMALL STREAM FLOODING IN THE INTERIOR AND
NORTHWEST PORTIONS OF THE ISLAND FOR THE ENTIRE WEEK. ALTHOUGH THE
SOUTH COAST WILL BE WARM...OF COURSE...THE NORTH COAST WILL ALSO
SEE TEMPERATURES RISE BETWEEN NOW AND THURSDAY... AND SAN JUAN
SHOULD BEGIN TO SEE A FEW LOWER 90S BY THE END OF THE WEEK.

AVIATION...-SHRA CAN BE EXPECTED FROM TIME TO TIME ACROSS MUCH OF
THE PR/USVI TERMINALS. ALSO...BKN/OVC HIGH CIRRUS WILL CONTINUE
ACROSS THE AREA. -TSRA/SHRA CAN STILL AFFECT THE LEEWARD
TERMINALS FROM TIME TO TIME...AND ALSO CAN MOVE ACROSS OR NEAR
THE USVI/SOUTHERN AND EASTERN PR TERMINALS THIS MORNING. DURING
THE AFTERNOON MTN TOP OBSCURATIONS OVER ERN...INTERIOR AND
NORTHWESTERN PR IN SHRA/LOW CIG ARE EXPECTED BETWEEN 01/15-23Z.
SFC WINDS FROM THE SOUTH AT 5 TO 10 KT WILL INCREASE TO 10 TO 15
KT AND LOCALLY HIGHER IN/NEAR TSRA/SHRA.

MARINE...SEAS ARE GRADUALLY MELLOWING OVER THE AREA...BUT WILL
INCREASE SOMEWHAT BETWEEN 5 AND 7 MAY. SMALL CRAFT ADVISORIES ARE
NOT EXPECTED DURING THE NEXT 7 DAYS AND SWELL FROM THE ATLANTIC
WILL BE MINIMAL.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  77  88  76 /  50  30  30  40
STT  83  78  87  76 /  50  50  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

23/11




000
FXCA62 TJSJ 010921
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
521 AM AST SUN MAY 1 2016

.SYNOPSIS...A TROUGH WITH A WEAK CUT-OFF LOW WILL PASS THROUGH
THE AREA TODAY. A SECONDS WEAKER TROUGH WILL PASS THROUGH ON
TUESDAY TO PROLONG THE TIME THE TROUGH STAYS IN PLACE. BY THURSDAY
A RIDGE WILL BEGIN TO BUILD OVER THE AREA...MOVING OVER THE
LEEWARD ISLANDS BY LATE IN THE WEEK.

AT MID LEVELS...CONSIDERABLE DRYING WILL TAKE PLACE TODAY AND ONLY
MODEST MOISTURE WILL PERSIST THROUGH THE END OF THE WEEK. WEAK
TROUGHINESS WILL PERSIST OVER THE AREA THROUGH MID WEEK...THEN
HIGH PRESSURE WILL BUILD INTO THE CENTRAL ATLANTIC AND OVER THE
CARIBBEAN SEA.

AT LOWER LEVELS...HIGH PRESSURE ENTERING THE WESTERN ATLANTIC AND
BUILDING INTO THE CENTRAL ATLANTIC WILL MAINTAIN SOUTHEAST TRADE
WIND FLOW THROUGH THE REST OF THE WEEK. ABUNDANT MOISTURE WILL
INCREASE OVER THE AREA AFTER MONDAY KEEPING SHOWERS AND
THUNDERSTORMS IN THE FORECAST.

&&

.DISCUSSION...SHOWERS AND THUNDERSTORMS HAD CLEARED OFF ALL BUT
THE SOUTHEAST PORTION OF THE FORECAST AREA BY LATE EVENING. BUT
THE LINE OF SHOWERS RETURNED AND NOW STRETCHES ACROSS THE
CARIBBEAN WATERS WITH SCATTERED SHOWERS. SHOWERS WENT OVER SAINT
CROIX AROUND 4 AM AST BUT THE HEAVIEST SHOWERS WENT AROUND THE
RAIN GAGE AT THE AIRPORT IN FREDERIKSTED. SHOWERS ARE WEAKENING AS
THEY APPROACH SAINT JOHN...SAINT THOMAS AND PUERTO RICO...BUT A
FEW ARE EXPECTED TO ARRIVE BY 8 AM AST. WITH SKIES CLEARING
HEATING SHOULD MAKE THINGS UNSTABLE AGAIN AND SHOWERS AND
THUNDERSTORMS WILL DEVELOP OVER PUERTO RICO. MODELS BARELY SHOW
THE AREA WHERE SHOWERS ARE FIRING OFF NOW...BUT RATHER SHOW A
WIDE AREA OF MOISTURE WITH LITTLE FORM...MAKING THE FORECAST
PARTICULARLY DIFFICULT TODAY. HOWEVER THE GFS BRINGS SOME
DIVERGENCE AT UPPER LEVELS ACROSS THE CENTER OF PUERTO RICO TODAY
FROM THE SOUTHWEST WHICH SHOULD HELP CONVECTION. OTHERWISE EXPECT
THE CONVECTION TO REMAIN MAINLY SOUTH AND EAST OF PUERTO RICO AND
POSSIBLY OVER THE U.S. VIRGIN ISLANDS. WINDS CONTINUE FROM THE
SOUTHEAST AND EXPECT WARMER TEMPERATURES TODAY. MOISTURE REACHES A
MINIMUM OVERNIGHT TONIGHT...BUT STILL AROUND 1.5 INCHES OF
PRECIPITABLE WATER. THEN OVER THE WEEK IT GRADUALLY RISES TO TWO
INCHES AGAIN. THE MODEL ALSO HAS 1000-850 MB THICKNESSES RISING
OVER THE AREA WITH THE WARMEST PERIOD FRIDAY THROUGH SUNDAY.
BECAUSE MOISTURE RISES THROUGH THE WEEK...THE FORECAST CAPE AND
LIFTED INDEX ALSO SHOW MORE INSTABILITY AS THE WEEK CONTINUES. THE
ONLY AMELIORATING FACTOR IS THAT MID LEVEL MOISTURE REMAINS MODEST
THROUGHOUT THE PERIOD...SO THE FLOODING POTENTIAL SHOULD REMAIN
LOCALIZED TO URBAN AND SMALL STREAM FLOODING IN THE INTERIOR AND
NORTHWEST PORTIONS OF THE ISLAND FOR THE ENTIRE WEEK. ALTHOUGH THE
SOUTH COAST WILL BE WARM...OF COURSE...THE NORTH COAST WILL ALSO
SEE TEMPERATURES RISE BETWEEN NOW AND THURSDAY... AND SAN JUAN
SHOULD BEGIN TO SEE A FEW LOWER 90S BY THE END OF THE WEEK.

&&

.AVIATION...-SHRA CAN BE EXPECTED FROM TIME TO TIME ACROSS MUCH OF
THE PR/USVI TERMINALS. ALSO...BKN/OVC HIGH CIRRUS WILL CONTINUE
ACROSS THE AREA. -TSRA/SHRA CAN STILL AFFECT THE LEEWARD
TERMINALS FROM TIME TO TIME...AND ALSO CAN MOVE ACROSS OR NEAR
THE USVI/SOUTHERN AND EASTERN PR TERMINALS THIS MORNING. DURING
THE AFTERNOON MTN TOP OBSCURATIONS OVER ERN...INTERIOR AND
NORTHWESTERN PR IN SHRA/LOW CIG ARE EXPECTED BETWEEN 01/15-23Z.
SFC WINDS FROM THE SOUTH AT 5 TO 10 KT WILL INCREASE TO 10 TO 15
KT AND LOCALLY HIGHER IN/NEAR TSRA/SHRA.


&&

.MARINE...SEAS ARE GRADUALLY MELLOWING OVER THE AREA...BUT WILL
INCREASE SOMEWHAT BETWEEN 5 AND 7 MAY. SMALL CRAFT ADVISORIES ARE
NOT EXPECTED DURING THE NEXT 7 DAYS AND SWELL FROM THE ATLANTIC
WILL BE MINIMAL.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  77  88  76 /  30  40  30  40
STT  83  78  87  76 /  50  50  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

27/12




000
FXCA62 TJSJ 010156
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
956 PM AST SAT APR 30 2016

.UPDATE...IT REMAINED MOSTLY RAIN FREE ACROSS THE ISLANDS DURING
THE EVENING HOURS. THE FLASH FLOOD WATCH WAS LET TO EXPIRE AT 8 PM
AST FOR ALL LOCAL ISLANDS. HIGH CIRRUS CLOUDS WILL CONTINUE OVER
THE ISLANDS LEAVING VARIABLY CLOUDY SKIES. SOME SHOWERS CAN
DEVELOP OVER THE CARIBBEAN WATERS AND REACH THE COASTAL AREAS OF
THE ISLANDS THROUGH THE OVERNIGHT AND EARLY MORNING HOURS. LATEST
01/00Z TJSJ UPPER AIR SOUNDING CONTINUED TO INDICATE A DROP IN
PWAT FROM 1.94 INCHES EARLY THIS MORNING TO 1.75 INCHES
NOW...FORECAST SOUNDINGS INDICATE THAT PWAT SHOULD STAY SOMEWHAT
SIMILAR AND CONTINUE TO SLOWLY ERODE DURING THE NEXT FEW DAYS.
HOWEVER...WITH ANOTHER UPPER PERTURBATION MOVING OVER ON
SUNDAY...THE CHANCE FOR MORE RAIN AND THUNDERSTORMS STILL REMAIN
HIGH ACROSS THE FORECAST AREA. MINOR CHANGES MADE TO SHORT TERM
GRIDS.


&&


.AVIATION UPDATE...VFR OVERNIGHT ACROSS MUCH OF THE PR/USVI
TERMINALS. HOWEVER...BKN/OVC HIGH CIRRUS WILL CONTINUE ACROSS THE
AREA. -TSRA/SHRA CAN STILL AFFECT FROM TIME TO TIME THE LEEWARD
TERMINALS...INCREASING ACROSS THE USVI/SOUTHERN AND EASTERN PR
TERMINALS BY SUNDAY MORNING. LATEST TJSJ SOUNDING INDICATED SOUTH
WINDS BLO FL040 AT 10-20 KNOTS.


&&

.MARINE UPDATE...BUOYS ACROSS PR AND THE USVI ARE INDICATING SEAS
BETWEEN 2 TO 4 FEET AND SOUTH-SOUTHEAST WINDS AROUND 10 KNOTS.
SEAS SHOULD CONTINUE BELOW SMALL CRAFT ADVISORY CRITERIA FOR THE
NEXT SEVERAL DAYS.

&&

.CLIMATE...AS OF 5 PM AST...A RECORD RAINFALL OF 2.33 INCHES WAS
SET AT HENRY E. ROHLSEN AIR PORT IN ST. CROIX TODAY. THIS BROKE
THE PREVIOUS RECORD OF 1.20 INCHES SET BACK IN 2009.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...AMPLIYING UPPER LEVEL TROUGH JUST WEST OF HISPANOLA IS
ENHANCING THE INSTABILITY AND MOISTURE TRANSPORT OVER PUERTO RICO
AND THE U.S. VIRGIN ISLANDS. ADDITIONAL MID TO UPPER SHORT-WAVE
TROUGHS WILL CONTINUE TO STREAM OVER THE LOCAL REGION THROUGH
NEXT WEEK. AMPLE AREA OF MOISTURE WILL REMAIN OVER THE NORTHEAST
CARIBBEAN REGION OVER THE NEXT SEVERAL DAYS. AS A RESULT...HIGHLY
UNSTABLE AND MOIST ATMOSPHERE REMAINS OVER THE FORECAST AREA...
FAVORING THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS EVERYDAY.
UNSETTLED PATTERN WILL LIKELY PREVAIL UNTIL AT LEAST EARLY NEXT
WEEK.

DISCUSSION...VERY UNSTABLE AND MOIST AIR MASS OVER THE FORECAST
AREA HAVE RESULTED IN THE DEVELOPMENT SHOWERS AND THUNDERSTORMS
WITH HEAVY RAINFALL ACROSS MOST OF THE FORECAST AREA. INTENSE
THUNDERSTORMS MOVED FROM WEST TO EAST SINCE EARLY THIS MORNING
AFFECTING THE WEST...SOUTH AND EAST PORTIONS OF PUERTO RICO
THROUGH LATE THIS MORNING. AT THIS TIME...MOST OF THUNDERSTORMS
HAVE MOVED OVER CULEBRA...VIEQUES AND THE U.S. VIRGIN ISLANDS.
TORRENTIAL RAINS...FREQUENT LIGHTNING AND GUSTY WINDS UP TO 35
KNOTS HAVE BEEN OBSERVED WITH THE HEAVIEST STORMS.

VERY MOIST SOUTHEASTERLY FLOW ACROSS THE EASTERN CARIBBEAN WILL
CONTINUE TO PROMOTE MOISTURE CONVERGENCE ACROSS PUERTO RICO AND
THE US VIRGIN ISLANDS EARLY NEXT WEEK. THIS COMBINES WITH INFLOW
OF MID LEVEL ENERGY AND FAVORABLE JET DYNAMICS WILL SUSTAIN
UNSETTLED CONDITIONS OVER THE NEXT SEVERAL DAYS. SOILS ARE
RELATIVELY SATURATED ACROSS MOST OF THE ISLANDS AND ADDITIONAL
HEAVY RAINFALL WILL INCREASE THE FLOODING THREAT ACROSS PR AND THE
USVI. FOR THIS REASON...A FLASH FLOOD WATCH REMAIN IN EFFECT UNTIL
AT LEAST 8 PM AST TONIGHT.

PATTERN WILL REMAIN HIGHLY FAVORABLE AND CONDUCIVE TO ORGANIZED
DEEP CONVECTION OVER THE NEXT SEVERAL DAYS. HIGH MOISTURE CONTENT
AND ADDITIONAL PERTURBATIONS AT MID-UPPER LEVELS WILL KEEP THE
CHANCES OF SHOWERS AND THUNDERSTORMS HIGH THROUGH THE FORECAST
PERIOD.

AVIATION...BRK IN CLD COVER OVR WRN PR TJBQ...TJMZ...TJPS.
HOWEVER...OVR ERN HALF OF PR AND EASTWARD TOWARDS THE NRN LEEWARDS
MULTIPLE CLD LYRS...SCT-BKN LYRS FL025...050...OVC BTW FL090-120.
ISOLD-SCT TSRA EN ROUTE BTW PR AND NRN LEEWARDS WITH LINE OF STRONG
SHRA/TSRA NOW CROSSING VIRGIN ISLANDS AND MOV W WITH MVFR/IFR CONDS
ATTM. MAX TOPS 450-500. MTN TOP OBSCR OVER ERN PR IN SHRA/LOW CIG
TIL 30/23Z. TEMPO MVFR/PSBL IFR CIG AND SHRA/TSRA EN ROUTE BTW
ISLANDS DURG PRD. PREVAILING VFR AT MOST LOCAL TERMINALS EXCEPT FOR
TEMPO IFR AT TISX...TIST WITH BRIEF MVFR IN SHRA/ISOLD TSRA
ELSEWHERE TIL 30/23Z.

MARINE...WINDS OF 5 TO 15 KNOTS AND SEAS OF 3 TO 5 FEET
RESPECTIVELY. MAIN HAZARD FOR MARINERS TODAY IS THE STRONG
THUNDERSTORMS OVER THE REGIONAL WATERS...ESPECIALLY NEAR
USVI...CULEBRA AND VIEQUES. SUDDEN WATERSPOUT WILL ALSO BE
POSSIBLE MAINLY BETWEEN EASTERN PUERTO RICO AND THE VIRGIN
ISLANDS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  75  88  75  87 /  20  50  40  30
STT  76  88  76  85 /  40  60  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
AM...NONE.
&&

$$

08/13




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