Caribbean - Central America Weather

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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
611 AM AST THU APR 7 2016

.SYNOPSIS...AT UPPER LEVELS...A WEAK TROUGH PASSED MAINLY TO THE
NORTH OF PUERTO RICO AND THE U.S. VIRGIN ISLANDS OVERNIGHT. BY SATURDAY
A RIDGE WILL BEGIN TO BUILD OVER THE AREA. A TROUGH ACCOMPANIED BY
A MODERATE JET WILL SPREAD OVER THE AREA MONDAY NIGHT AND NOT
EXIT UNTIL WEDNESDAY NIGHT. A RIDGE WILL FORM OVER THE LEEWARD
ISLANDS TOWARD THE END OF NEXT WEEK.

AT MID LEVELS...HIGH PRESSURE WILL CONTINUE OVER THE CARIBBEAN
UNTIL MONDAY. A SHORT WAVE TROUGH WILL PASS THROUGH THE AREA
TUESDAY AND LINGER UNTIL THURSDAY. LIMITED MOISTURE WILL BE
PRESENT THURSDAY AND AGAIN MONDAY AND TUESDAY. OTHERWISE MID
LEVELS ARE VERY DRY.

AT LOWER LEVELS...LOW PRESSURE CONTINUES OVER NORTHERN SOUTH
AMERICA. HIGH PRESSURE WILL MOVE NORTHEAST AND BUILD OVER THE
NORTH CENTRAL ATLANTIC WHILE A TROUGH MOVES INTO THE WESTERN
ATLANTIC. WEAK RIDGING PERSISTS OVER THE BAHAMAS. HIGH PRESSURE
RETURNS TO THE WESTERN ATLANTIC ON SUNDAY. MODERATE TRADE WIND
FLOW WILL CONTINUE UNTIL AT LEAST EARLY NEXT WEEK. THE LATEST GFS
SHOWS TROUGHINESS DEEPENING OVER THE AREA MID WEEK NEXT WEEK AND A
LOW FORMING TO THE NORTH.

&&

.DISCUSSION...NORTHEAST TO EAST NORTHEAST FLOW HAS BROUGHT SHOWERS
AND UP TO ONE QUARTER INCH OF RAIN TO THE NORTH COAST OF PUERTO
RICO. MORE RAIN ALSO FELL OVER THE EASTERN TIP OF THE ISLAND. ONLY
TRACES WERE SEEN IN SAINT THOMAS AND SAINT JOHN. MOISTURE PEAKS
TODAY AS THE UPPER LEVEL TROUGH MOVES PAST THE AREA AND MOISTURE LESSENS
SOMEWHAT ON FRIDAY. WHEN MID LEVELS MOISTEN ON MONDAY AND THE
INVERSION AT THE BOTTOM OF THE MID LEVELS DISSIPATES...SHOWERS
WILL BEGIN TO BECOME MORE FREQUENT. OTHERWISE MOSTLY ISOLATED
SHOWERS WILL BE SEEN FROM THE SHALLOW MARINE LAYER. ON TUESDAY AND
WEDNESDAY MOISTURE DEEPENS AND THERE ARE FAVORABLE DYNAMICS FROM
AN UPPER LEVEL JET THAT SHOULD GENERATE AT LEAST ISOLATED
THUNDERSTORMS IN THE INTERIOR OF PUERTO RICO.

ALTHOUGH THE GFS SHOWS LOW PRESSURE FORMING ONLY A FEW HUNDRED
MILES NORTH OF PUERTO RICO AS EARLY AS TUESDAY HAVE LOW
CONFIDENCE THAT THIS SCENARIO WILL PLAY OUT EXACTLY AS
DEPICTED...BUT THIS COULD WAFT VERY MOIST AIR OVER THE AREA FROM
THE SOUTHEAST JUST BEYOND 240 HOURS AFTER THE LOW LEAVES.

&&

.AVIATION...AS A FRONTAL BOUNDARY CONTINUES TO MOVE EAST ACROSS
THE ATLANTIC...SHRA WILL CONTINUE ACROSS THE FLYING AREA TODAY. SOME
SHRA WILL IMPACT THE NORTHERN TERMINALS OF
TJSJ/TIST/TISX/TNCM/TKPK WITH VCSH AND POSSIBLE -RA AT TIMES. AVAILABLE
MOISTURE WILL PRODUCE SHRA OVER THE INTERIOR AND WESTERN SECTIONS
OF PR AFFECTING TJBQ/TJMZ AFT 07/15Z. LOW LEVEL WINDS VEERING TO THE
E-ESE AROUND 10 KNOTS WITH SEA BREEZE VARIATIONS AFTER 07/13Z.


&&

.MARINE...A 4 TO 5 FOOT SWELL IS STILL EXPECTED BEGINNING TONIGHT
AND TOMORROW IN THE ATLANTIC. THIS WILL PUSH SEAS IN THE ATLANTIC
BACK INTO THE 4 TO 6 FOOT RANGE. IT IS POSSIBLE THAT SEAS THAT
ARRIVE WILL BE SLIGHTLY HIGHER...BUT HAVE GONE WITH PREVIOUS
FORECAST UNTIL THE OUTER BUOY GIVES INDICATIONS THAT SMALL CRAFT
ADVISORIES MIGHT BE NEEDED.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 75 89 75 / 50 30 30 20
STT 85 76 86 75 / 40 30 20 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
146 PM AST THU APR 7 2016

.SYNOPSIS...SURFACE HIGH PRESSURE ACROSS THE NORTH CENTRAL
ATLANTIC IS EXPECTED TO DOMINATE FOR THE NEXT SEVERAL
DAYS...KEEPING US UNDER A LIGHT TO MODERATE TRADE WIND FLOW. ZONAL
FLOW IN THE UPPER LEVELS EXPECTED TO CONTINUE ALSO FOR THE NEXT
SEVERAL DAYS. THEN ON MONDAY A WEAK UPPER TROUGH WITH A MODERATE
JET APPROACHES THE LOCAL AREA UNTIL WEDNESDAY. A TYPICAL PATTERN
OF ISOLATED TO SCATTERED PASSING SHOWERS IN THE MORNING AND
OVERNIGHT HOURS WITH AFTERNOON CONVECTION DUE TO LOCAL EFFECTS IS
EXPECTED FOR THE NEXT SEVERAL DAYS.


&&

.DISCUSSION...THE OVERALL SETUP FOR TODAY GAVE WAY TO THE EXPECTED
WEATHER CONDITIONS OF PASSING SHOWERS IN THE MORNING THEN
AFTERNOON CONVECTION IN AREAS OF SEA BREEZE CONVERGENCE AS WELL AS
DOWNSTREAM FROM EL YUNQUE...AFFECTING THE SAN JUAN AREA. THE USVI
OBSERVED LITTLE TO NO RAIN BUT SOME SHOWERS COULD STREAM OFF THE
ISLANDS LATER IN THE AFTERNOON.

THESE SHOWERS WERE DUE TO THE COMBINATION OF DIURNAL HEATING AND
THE LOCAL EFFECTS. NO THUNDERSTORMS WERE OBSERVED AND THEY ARE NOT
EXPECTED AS THE UPPER LEVELS ARE NOT REALLY SUPPORTIVE FOR
THUNDERSTORM DEVELOPMENT. IF BY CHANCE A THUNDERSTORMS WERE TO
DEVELOP LATER IN THE AFTERNOON IT WOULD BE VERY SHORT LIVED...BUT
AGAIN THEY ARE NOT EXPECTED. HAVING SAID THAT...THE AVAILABLE
MOISTURE IS ENOUGH TO CAUSE SOME GOOD SHOWERS...WHICH COULD LAST
THROUGH THE AFTERNOON ACROSS WESTERN PR IN PARTICULAR.

THE NEXT FEW DAYS LOOK RATHER SIMILAR TO WHAT HAPPENED TODAY.
EASTERLY WINDS WILL PREVAIL FOR THE NEXT FEW DAYS WHICH WOULD THEN
PUSH THE AFTERNOON CONVECTION TO THE WESTERN SECTIONS OF PR WITH
STREAMERS FROM EL YUNQUE POSSIBLY AFFECTING PORTIONS OF THE SAN
JUAN AREA AND SOME STREAMING OFF THE USVI...CAUSING RAINFALL
ACROSS THE WESTERN SECTIONS OF THE ISLANDS.

NO REAL CHANGE IN PATTERN IS EXPECTED UNTIL MONDAY WHEN A WEAK
UPPER TROUGH APPROACHES THE LOCAL AREA...CAUSING SLIGHTLY MORE
INSTABILITY AND THEREFORE THE CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS. THEN FOR MID TO LATE NEXT WEEK...MOISTURE LOOKS
LIKE IT WILL DECREASE AS A SURFACE LOW DEVELOPS TO THE NORTH OF
THE AREA BUT THE MOISTURE STAYS TO OUR EAST AND NORTH BECAUSE WE
ARE IN THE LOCATION OF THE LOW PRESSURE THAT WOULD BE AFFECTED BY
THE NORTHERLY WINDS.


&&

.AVIATION...SHRA WILL CONTINUE OVER THE WESTERN INTERIOR AND
NORTHERN COASTAL AREAS OF PR...IMPACTING MAINLY THE FLYING AREA OF
TJBQ/TJMZ/TJSJ AT LEAST UNTIL 22Z-23Z. SCT-BKN AND OCCASIONAL OVC
LAYERS BTW FL030-FL070 LIKELY THRU EARLY EVENING. MAX TOPS SO FAR
NEAR TJBQ AROUND FL200. -TSRA COULD STILL DEVELOP BY MID AFTERNOON
NEAR TJBQ/TJMZ. REGARDLESS...+SHRA/SHRA OVER W INTERIOR CAN CREATE
MVFR CONDS. LOW LEVEL E-ESE WINDS WILL CONTINUE AROUND 10-15 KNOTS
WITH SEA BREEZE VARIATIONS ACROSS NRN/WESTERN PR TERMINALS THRU 21Z.
MAINLY VFR ELSEWHERE.


&&

.MARINE...SEAS WILL BE GENERALLY 2 TO 5 FEET ACROSS THE LOCAL
WATERS TODAY AND TONIGHT...BRIEFLY INCREASING TO 6 FEET ON FRIDAY
THEN UP TO 5 FEET ONCE AGAIN ON SATURDAY AND FOR THE NEXT FEW
DAYS. THERE IS A MODERATE RISK OF RIP CURRENTS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 89 75 88 / 30 30 20 20
STT 76 86 75 86 / 30 20 30 10

[cycloneye]

Is long range (April 18) so is too erly to say this rain event for the Eastern Caribbean will occur so stay tuned as the days go by to see if changes come.

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
526 AM AST FRI APR 8 2016

.SYNOPSIS...AT UPPER LEVELS...A RIDGE WILL BUILD OVER THE AREA AND
MOVE ACROSS TONIGHT. A TROUGH NORTH OF CUBA ON SUNDAY NIGHT WILL
CROSS THROUGH THE AREA MONDAY NIGHT. THEN A JET STREAK WILL SETTLE
SOUTHEAST OVER THE AREA. ANOTHER TROUGH WILL MOVE OVER CUBA ON
FRIDAY TO KEEP FAVORABLE DYNAMICS OVER PUERTO RICO AND THE U.S.
VIRGIN ISLANDS TUESDAY THROUGH THE FOLLOWING SUNDAY.

AT MID LEVELS...HIGH PRESSURE WILL CONTINUE OVER THE CARIBBEAN SEA
UNTIL EARLY NEXT WEEK. A WEAK TROUGH WILL PASS THROUGH ON TUESDAY
AND AGAIN ON THE FOLLOWING SUNDAY. MID LEVELS WILL HAVE MODEST MOISTURE
TUESDAY AND WEDNESDAY AND AGAIN ON THE FOLLOWING WEEKEND.

AT LOWER LEVELS...HIGH PRESSURE OVER THE NORTH CENTRAL ATLANTIC
WILL WEAKEN TODAY THROUGH MONDAY. A TROUGH WILL MOVE INTO THE
WESTERN ATLANTIC TODAY FOLLOWED BY ANOTHER LOW PRESSURE ON
SATURDAY...BUT RIDGING WILL CONTINUE ACROSS THE SUBTROPICAL
ATLANTIC. AS THESE LOWS MOVE RAPIDLY NORTHEAST HIGH PRESSURE WILL
AGAIN RECLAIM THE WESTERN ATLANTIC AND BUILD OVER THE ENTIRE
CENTRAL ATLANTIC DURING THE FIRST HALF OF NEXT WEEK. THE FRONT
THAT WILL APPROACH THE AREA LATE NEXT WEEK IS EXPECTED TO STALL
WITHOUT PASSING. THE DISSIPATING FRONT TO OUR NORTH IS NOW IN
RETREAT.

&&

.DISCUSSION...SHOWERS WERE WIDELY SCATTERED ACROSS THE LOCAL
WATERS TODAY WITH A FEW AFFECTING SOUTHERN PUERTO RICO AND SAINT
CROIX. ALTHOUGH THE GFS SHOWS DRIER AIR MOVING IN FROM THE EAST
SOUTHEAST...IT WILL BE TOO LATE TO PREVENT ANOTHER ROUND OF
SCATTERED TO NUMEROUS SHOWERS FOR PUERTO RICO...MAINLY IN THE
WEST. SHOWERS ARE ALSO EXPECTED IN A SIMILAR FASHION ON SATURDAY
ALTHOUGH MOISTURE WILL BE AT ITS LOWEST POINT OF THE NEXT 10 DAY
LATE SATURDAY AFTERNOON. MOISTURE INCREASES CONSIDERABLY MONDAY
AND TUESDAY...AND DIVERGENCE ALOFT BEGINS MONDAY EVENING WITH THE
APPROACH OF AN UPPER LEVEL JET STREAM OVER THE AREA AND CONTINUES
WITH A FEW BREAKS THROUGH THE REST OF THE WEEK. THAT JET STREAM
WILL REACH 75 TO 85 KNOTS OVER THE LOCAL AREA TUESDAY THROUGH
FRIDAY. ALTHOUGH DYNAMICS ARE GOOD...MID LEVELS DRY AGAIN LATE
WEDNESDAY AND THURSDAY AND SHOWERS WILL DIMINISH THEN. CURRENT
INDICATIONS ARE THAT ANY FLOODING TO OCCUR WILL BE LIMITED TO URBAN
AREAS AND SMALL STREAMS AND HEAVY RAINFALL WILL BE QUITE
LOCALIZED. MOISTURE DURING THE FOLLOWING WEEKEND IS CURRENTLY
BEING SHOWN JUST SLIGHTLY LESS THAN THAT TO OCCUR ON TUESDAY AND
WEDNESDAY.

&&

.AVIATION...VFR CONDS EXPECTED THRU THE FORECAST PERIOD EXCEPT AS
NOTED. SOME SHRA POSSIBLE IN THE VICINITY/OVER
TJSJ/TIST/TISX/TNCM AND TJPS FROM TIME TO TIME EARLY IN THE
MORNING. FOLLOWED BY AFTERNOON CONVECTION OVER THE INTERIOR AND
WESTERN SECTIONS OF PR...WITH SOME OF THEM MOVING OVER TJBQ/TJMZ
BRINGING MVFR CIGS/VSBYS AND MTN OBSCURATIONS BTWN 08/17-23Z. IN
ADDITION...SHRA CAN BE EXPECTED DOWNWIND FROM EL YUNQUE AND MOVING
IN THE VICINITY OR ACROSS TJSJ BETWEEN 18Z- 22Z. CALM- LIGHT/VRB
WINDS...AFT 08/12Z FROM THE E-ESE AT 10-15 KT WITH SEA BREEZE
VARIATIONS.

&&

.MARINE...SEAS PEAKED AT 9.2 FEET AT THE OUTER BUOY AND AFTER A
BRIEF DROP BELOW 8 FEET ARE NOW AROUND 8.6 FEET. THE BUOY IS
REPORTING THE WAVES AS NORTH NORTHWEST SWELL WITH A PERIOD OF 13
TO 14 SECONDS. THIS SWELL WILL ARRIVE ON THE COAST DURING THE
MORNING HOURS AND SUBSIDE OVERNIGHT. THE INNER BUOY 41053 HAS BEEN
REMOVED FOR ITS ANNUAL MAINTENANCE AND SO WAVE HEIGHT READINGS
WILL BE UNAVAILABLE FOR THIS EPISODE. NEVERTHELESS CALCULATIONS
SHOW THAT 8 TO 10 FOOT BREAKING WAVES CAN BE EXPECTED ON THE
PUERTO RICO COAST WITH WAVES AS HIGH AS 12 FEET IN CERTAIN PLACES.
A HIGH SURF ADVISORY HAS BEEN ISSUED. THIS WILL CAUSE HIGH RISK
OF RIP CURRENTS ACROSS ALL OF THE NORTHERN COASTS OF PUERTO RICO
INCLUDING CULEBRA AND ALSO ALONG THE NORTH-FACING BEACHES OF
SAINT THOMAS. SEAS WILL SUBSIDE SLOWLY AND SMALL CRAFT ADVISORY
CONDITIONS ARE NOT EXPECTED TO COMPLETELY DISAPPEAR UNTIL SATURDAY
AFTERNOON.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 75 89 75 / 20 20 20 40
STT 86 75 86 73 / 20 30 10 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
153 PM AST FRI APR 8 2016

.SYNOPSIS...SURFACE HIGH PRESSURE ACROSS THE NORTH CENTRAL
ATLANTIC IS EXPECTED TO DOMINATE THE LOCAL WIND PATTERN FOR THE
NEXT SEVERAL DAYS...EVEN THOUGH THERE IS A SURFACE LOW EXPECTED TO
MOVE ALONG THE EAST COAST OF THE US...KEEPING US UNDER A LIGHT TO
MODERATE TRADE WIND FLOW. ZONAL FLOW IN THE UPPER LEVELS EXPECTED
TO CONTINUE THROUGH THE WEEKEND. THEN ON MONDAY A WEAK UPPER
TROUGH WITH A MODERATE JET APPROACHES THE LOCAL AREA UNTIL
WEDNESDAY. A TYPICAL PATTERN OF ISOLATED TO SCATTERED PASSING
SHOWERS IN THE MORNING AND OVERNIGHT HOURS WITH AFTERNOON
CONVECTION DUE TO LOCAL EFFECTS IS EXPECTED FOR THE NEXT SEVERAL
DAYS.


&&

.DISCUSSION...THE OVERALL SETUP FOR TODAY GAVE WAY TO THE EXPECTED
WEATHER CONDITIONS OF PASSING SHOWERS IN THE MORNING ACROSS THE
WATERS...USVI...AND EASTERN PR. THEN AFTERNOON CONVECTION IN
AREAS OF SEA BREEZE CONVERGENCE...OROGRAPHIC LIFTING...AS WELL AS
DOWNSTREAM FROM EL YUNQUE...AFFECTING THE SAN JUAN AREA. THE USVI
OBSERVED LITTLE TO NO RAIN BUT SOME SHOWERS COULD STREAM OFF THE
ISLANDS LATER IN THE AFTERNOON.

NO THUNDERSTORMS WERE OBSERVED AND THEY ARE NOT EXPECTED AS THE
UPPER LEVELS ARE NOT SUPPORTIVE FOR THUNDERSTORM DEVELOPMENT. HAVING
SAID THAT...THE AVAILABLE MOISTURE IS ENOUGH TO CAUSE SOME GOOD
SHOWERS...WHICH COULD LAST THROUGH THE AFTERNOON ACROSS WESTERN
PR IN PARTICULAR.

THE NEXT FEW DAYS LOOK RATHER SIMILAR TO WHAT HAPPENED TODAY.
EASTERLY WINDS WILL PREVAIL FOR THE NEXT FEW DAYS WHICH WOULD THEN
PUSH THE AFTERNOON CONVECTION TO THE WESTERN SECTIONS OF PR WITH
STREAMERS FROM EL YUNQUE POSSIBLY AFFECTING PORTIONS OF THE SAN
JUAN AREA AND SOME STREAMING OFF THE USVI...CAUSING RAINFALL
ACROSS THE WESTERN SECTIONS OF THE ISLANDS. FOR TOMORROW AFTERNOON...THE
AREA WITH THE HIGHEST CHANCE OF RAIN IS THE NW QUADRANT OF PR WITH
A SLIGHT CHANCE OF A THUNDERSTORM.

NO REAL CHANGE IN PATTERN IS EXPECTED UNTIL MONDAY WHEN A WEAK
UPPER TROUGH APPROACHES THE LOCAL AREA...CAUSING SLIGHTLY MORE
INSTABILITY AND THEREFORE THE CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS. THEN FOR MID TO LATE NEXT WEEK...MOISTURE LOOKS
LIKE IT WILL DECREASE AS A SURFACE LOW DEVELOPS TO THE NORTH OF
THE AREA BUT THE MOISTURE STAYS TO OUR EAST AND NORTH BECAUSE WE
ARE IN THE LOCATION OF THE LOW PRESSURE THAT WOULD BE AFFECTED BY
THE NORTHERLY WINDS.


&&

.AVIATION...MAINLY VFR ACROSS ALL TERMINALS DURING THE NEXT 24
HOURS. HOWEVER...SHRA WITH ISOLATED TOPS AROUND FL200 OVER N/NW PR
COULD CREATE BRIEF MVFR...MAINLY AT TJBQ THRU AT LEAST 22Z.
-SHRA IN TRADE WINDS EXPECTED OVERNIGHT BTW NRN LEEWARDS AND THE
USVI. SEA BREEZE VARIATIONS UNTIL 20Z ACROSS NRN/WESTERN PR
TERMINALS. LIGHT AND VARIABLE WINDS AT THE SFC OVERNIGHT. LOW LEVEL
WINDS FM THE EAST TO SOUTHEAST AT 10-15 KT.


&&

.MARINE...MODEL GUIDANCE GROSSLY UNDERESTIMATED THE WAVE HEIGHTS
FOR THE SWELL CURRENTLY AFFECTING THE LOCAL WATERS. THE SEAS ARE
CURRENTLY AT 9 FEET AT BUOY 40143 IN THE OUTER ATLANTIC WATERS
NORTH OF PR WITH A NNW SWELL...AND 7 FEET AT THE RINCON
BUOY...WITH A PERIOD GENERALLY BETWEEN 12 AND 14 SECONDS MEASURED
AT BOTH BUOYS. THEREFORE THERE IS A HIGH SURF ADVISORY FOR ALL OF
THE NORTH COAST OF PR...A SMALL CRAFT ADVISORY FOR MANY OF THE
LOCAL WATERS AND A HIGH RISK OF RIP CURRENTS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 89 75 87 / 20 20 40 20
STT 75 86 73 85 / 30 10 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
548 AM AST SAT APR 9 2016

.SYNOPSIS...A RIDGE PATTERN FOLLOWED BY ZONAL FLOW AT UPPER
LEVELS WILL CONTINUE OVER THE REGION DURING THE NEXT FEW DAYS.
THEN...AN UPPER LEVEL TROUGH IS EXPECTED TO MOVE ACROSS THE LOCAL
REGION BETWEEN MONDAY AND LATE TUESDAY. AT THE SURFACE...ALTHOUGH
A LOW PRESSURE WILL MOVE INTO THE WESTERN ATLANTIC TODAY CRUSHING
THE SURFACE HIGH PRESSURE OVER THE CENTRAL ATLANTIC...THE WEAK
RIDGE SOUTH OF THE HIGH WILL DOMINATE THE LOCAL WIND PATTERN.
ANOTHER SURFACE HIGH WILL EXIT THE EASTERN U.S. AND DRIFT
NORTHEASTWARD ACROSS THE WESTERN ATLANTIC OCEAN.

&&

.DISCUSSION...
A FAIR WEATHER PATTERN PERSISTED OVERNIGHT ACROSS THE LOCAL AREA.
A FEW PASSING SHOWERS WERE OBSERVED MAINLY OVER THE LOCAL WATERS
AND SOME OF THEM MOVED INLAND BUT WITHOUT ANY SIGNIFICANT IMPACT.
THIS FAIR WEATHER PATTERN IS EXPECTED TO CONTINUE TODAY AND
DURING THE WEEKEND...HOWEVER ONE CANNOT RULE OUT THE TYPICAL
PASSING OVERNIGHT AND MORNING SHOWERS OR AFTERNOON CONVECTION DUE
TO DIURNAL HEATING AND SEA BREEZE VARIATIONS DURING THE WEEKEND.
AT THIS MOMENT NO THUNDERSTORMS ARE INCLUDED IN THE FORECAST AS A
DRY AND SUBSIDENT AIR MASS PREVAILS ALOFT.

AN UPPER LEVEL TROUGH WITH A MODERATE JET IS EXPECTED TO REACH
THE LOCAL AREA ENHANCING THE FORMATION OF SHOWERS AND
THUNDERSTORMS ACROSS THE LOCAL AREA BETWEEN MONDAY AND WEDNESDAY.
GFS MODEL GUIDANCE IS INDICATING AN INCREASING TREND OF THE
RELATIVE HUMIDITY AT 500-700 MB EARLY NEXT WEEK. 500MB
TEMPERATURES ARE EXPECTED TO DROP BELOW THE NORMAL CLIMATOLOGICAL
VALUES FOR THE MONTH. AS ALL THESE INGREDIENTS COMBINE EXPECT AN
INCREASING POTENTIAL FOR SHOWERS AND THUNDERSTORMS BETWEEN MONDAY
AND WEDNESDAY.

&&

.AVIATION...FOR THE LEEWARD ISLANDS. SCT SHRA MOVING WEST INTO AREA
ARND 12Z FOLLOWED BY CLRG. VFR PREVAILING XCP FOR SOME MVFR IN
SHRA TIL 15Z. FOR PR AND THE USVI VFR. AFT 17Z AREAS SHRA DVLPG
WRN INTERIOR PR SPRDG TO NW PR WITH LCL MTN OBSCURATIONS AND BRIEF
MVFR CONDS PSBL TIL ARND 09/23Z. WINDS ESE WITH LAND/SEA BREEZE
VARIATIONS 2 TO 8 KT TIL 09/14Z AND 8 TO 18 KT AFT 09/14Z. WINDS
ALF BCM WLY ABV FL160 WITH MAX WINDS NR FL410 INCRG FM 50KT AT
09/06Z TO 65 KT AT 10/00Z AS WINDS STRENGTHEN ARND WSW JET NOW
THRU TUES.

&&

.MARINE...ALTHOUGH THE MARINE CONDITIONS ARE EXPECTED TO GRADUALLY
IMPROVE TODAY...MARINERS SHOULD EXERCISE CAUTION ACROSS THE LOCAL
WATERS DUE TO SEAS UP TO 6 FT WITH OCCASIONAL SEAS UP TO 8 FT. THE
OFFSHORE BUOY...41043...CONTINUES AROUND 7 FEET BUT IS SHOWING A
DECREASING TREND. THIS TREND WILL CONTINUE...THEREFORE WAVE
HEIGHTS ARE FORECAST TO SUBSIDE TO AROUND 4-6 FT ACROSS MOST OF
THE WATERS THIS MORNING. THE SEAS WILL LIKELY BUILD TO 5 TO 7 FT
ONCE AGAIN ACROSS THE ATLANTIC WATERS MONDAY AND TUESDAY AS
EASTERLY WINDS INCREASE.

BEACH GOERS SHOULD READ THE SURF ZONE FORECAST TO IDENTIFY WHICH
BEACHES ARE AT HIGH RISK OF RIP CURRENTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 75 87 76 / 20 40 20 40
STT 86 73 85 75 / 20 20 20 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
210 PM AST SAT APR 9 2016

.SYNOPSIS....A WEAKENING RIDGE PATTERN ALOFT AND A SOMEWHAT ZONAL
FLOW WILL CONTINUE OVER THE REGION DURING THE REST OF THE WEEKEND.
AN UPPER LEVEL TROUGH IS EXPECTED TO MOVE ACROSS THE LOCAL REGION
BETWEEN MONDAY AND TUESDAY. AT THE SURFACE...AREA OF LOW PRESSURE
AND ASSOCIATED COLD FRONT WILL CONTINUE TO MOVE ACROSS THE WESTERN
ATLANTIC ATLANTIC TODAY AND SUNDAY...AS THE ATLANTIC HIGH PULLS
NORTHEAST ACROSS THE NORTH CENTRAL ATLANTIC. ANOTHER SURFACE HIGH
WILL EXIT THE EASTERN U.S. AND SPREAD ACROSS THE WESTERN ATLANTIC
OCEAN ON MONDAY AND TUESDAY.

&&

.DISCUSSION...MID-UPPER RIDGE IS TO CONTINUE TO DOMINATE THE NORTHEASTERN
CARIBBEAN TODAY AND FOR MOST OF THE WEEKEND. HOWEVER RECENT MODEL GUIDANCE
HAS BEEN PERSISTENT IN SUGGESTING DEEPENING OF AN UPPER TROUGH AS
IT APPROACHES THE REGION BY EARLY NEXT WEEK. BY LATE SUNDAY AND MONDAY
UPPER TROUGH IS STILL FORECAST TO MOVE ACROSS HISPANIOLA PLACING THE
REGION IN AN AREA MORE FAVORABLE FOR ENHANCED CONVECTIVE INSTABILITY.
THIS WILL RESULT IN INCREASING POTENTIAL FOR SHOWERS AND THUNDERSTORMS
ESPECIALLY OVER PARTS OF THE INTERIOR AND WEST SECTIONS OF PUERTO RICO
DURING THE DAY THROUGH AT LEAST THE EARLY PART OF THE NEXT WEEK. THE
POTENTIAL FOR CONVECTIVE ACTIVITY WILL THEN GRADUALLY DIMINISH DURING
THE LATTER PART OF THE WEEK...AS THE UPPER TROUGH BEGINS TO WEAKEN...AND
CONSEQUENTLY LESSER CHANCE FOR SHOWERS AND THUNDERSTORM ACTIVITY.

&&

.AVIATION...MOSTLY VFR CONDS THROUGH THE FORECAST PERIOD. SHRA AFTER
09/18Z...AFFECTING THE VICINITY OF TJPS/TJMZ/TJBQ AND TJSJ. SHRA
NEAR TJBQ COULD PERSIST INTO THE LATE AFTERNOON HOURS. WINDS WILL
PREVAIL FROM THE EAST TO ESE AT AROUND 15KT WITH OCCASIONAL GUSTS
AND SEA BREEZE VARIATIONS THROUGH 09/22Z. VCSH TONIGHT IN QUICK
PASSING SHRA POSSIBLY AFFECTING THE VICINITY OF TJSJ...THE USVI
AND THE LEEWARDS OVERNIGHT. WINDS DIMINISHING TO ABOUT 5-10KT FROM
THE EAST STARTING AT 09/23Z WITH OCCASIONAL LIGHT AND VRB.

&&

.MARINE...OFFSHORE BUOY 41043 CONTINUES TO SUGGEST SUBSIDING SEAS
BUT STILL NEAR 7 FEET. HOWEVER...EXPECT SEAS TO CONTINUE TO SUBSIDE
TO AROUND 4-6 FT ACROSS MOST OF THE LOCAL WATERS DURING THE REST
OF THE EVENING AND ON SUNDAY. SMALL CRAFT OPERATORS SHOULD THEREFORE
CONTINUE TO EXERCISE CAUTION ACROSS PORTIONS OF THE COASTAL
WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 88 78 87 / 30 30 30 30
STT 77 87 75 85 / 50 50 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
523 AM AST SUN APR 10 2016

.SYNOPSIS...THE RIDGE ALOFT WILL CONTINUE TO ERODE AS A MID TO
UPPER LEVEL TROUGH MOVES ACROSS THE WESTERN ATLANTIC. THIS TROUGH
WILL MOVE OVER THE COUNTY WARNING AREA BETWEEN LATE MONDAY AND
WEDNESDAY. A RIDGE PATTERN WILL RETURN BY THE END OF THE UPCOMING
WORK WEEK. AT THE SURFACE...AN AREA OF LOW PRESSURE AND AN ASSOCIATED
COLD FRONT WILL CONTINUE TO MOVE ACROSS THE WESTERN ATLANTIC
ATLANTIC TODAY...AS THE ATLANTIC HIGH PULLS NORTH ACROSS THE NORTH
CENTRAL ATLANTIC. ANOTHER SURFACE HIGH WILL EXIT THE EASTERN U.S.
SPREADING INTO THE WESTERN ATLANTIC ON MONDAY AND TUESDAY.

&&

.DISCUSSION....TRANQUIL WEATHER CONDITIONS PERSISTED OVERNIGHT
ACROSS THE LOCAL AREA. A FEW PASSING SHOWERS WERE OBSERVED MAINLY
OVER THE LOCAL WATERS AND SOME OF THEM MOVED INLAND BUT WITHOUT
ANY SIGNIFICANT IMPACT. EXPECT MAINLY FAIR WEATHER TODAY WITH
BRIEF PASSING SHOWERS ACROSS THE LOCAL WATERS AND WINDWARD AREAS
FOLLOWED BY SOME LOCALLY INDUCED AFTERNOON SHOWERS OVER THE
INTERIOR AND WESTERN SECTIONS OF PUERTO RICO. ELSEWHERE AND OVER
THE U.S. VIRGIN ISLANDS EXPECT MOSTLY SUNNY TO PARTLY CLOUDY SKIES
WITH BRIEF PASSING SHOWERS FROM TIME TO TIME.

ONCE AGAIN...GFS GUIDANCE STILL SUGGESTING AN UPPER LEVEL TROUGH
WITH A JET MOVING CLOSE TO THE AREA DURING THE PERIOD LATE MONDAY
AND WEDNESDAY. MODEL GUIDANCE INDICATED AN INCREASING TREND IN THE
RELATIVE HUMIDITY AT 500-700 MB WITH THE 500MB TEMPERATURES
DROPPING BELOW THE NORMAL CLIMATOLOGICAL VALUES FOR THE MONTH.
ALSO...INSTABILITY AT MID LEVELS IS FORECAST TO BE MORE CONDUCIVE
TO THE FORMATION OF DEEP CONVECTION ACROSS THE REGION. AS ALL
THESE INGREDIENTS COMBINE EXPECT AN INCREASING POTENTIAL FOR
SHOWERS AND THUNDERSTORMS MONDAY THROUGH WEDNESDAY.

&&

.AVIATION...MOSTLY VFR CONDS TIL 10/17Z. SCT SHRA DVLPG AFT
10/17Z WITH ISOLD MVFR CONDS AND LOCAL MTN OBSCURATIONS ACROSS
INTERIOR AND WESTERN PR. WINDS WILL PREVAIL FROM THE EAST TO ESE AT
AROUND 5 TO 10 KT TIL 10/14Z THEN INCREASING TO 10 TO 15 KT WITH SEA
BREEZE VARIATIONS. WINDS ALF BCMG WLY NR FL140. MAX WINDS WSW 80 KT
BY 11/00Z AT AND ARND FL460.

&&

.MARINE...MARINE CONDITIONS WILL CONTINUE TO IMPROVE THROUGH THE
DAY. HOWEVER...MARINERS SHOULD EXERCISE CAUTION ACROSS THE
ATLANTIC OFFSHORE WATERS AND ANEGADA PASSAGE DUE TO SEAS UP TO 6
FEET. ELSEWHERE...EXPECT SEAS 5 FEET OR LESS AND WINDS BELOW 18 KNOTS.
THE MARINE CONDITIONS WILL LIKELY DETERIORATE ACROSS THE LOCAL
WATERS AS THE UPPER LEVEL TROUGH MOVES CLOSE TO THE REGION MONDAY
NIGHT. PLEASE...STAY TUNED FOR ADDITIONAL INFORMATION ABOUT THE
EXPECTED MARINE WEATHER CONDITIONS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 78 87 76 / 30 30 30 40
STT 87 75 85 75 / 50 30 30 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
150 PM AST SUN APR 10 2016

.SYNOPSIS...RIDGE PATTERN ALOFT WILL CONTINUE TO ERODE AS AN UPPER
LEVEL TROUGH MOVES ACROSS THE WESTERN ATLANTIC...THEN APPROACHES
AND MOVES ACROSS THE LOCAL AREA MONDAY THROUGH TUESDAY. AT THE
SURFACE... AREA OF LOW PRESSURE AND WEAKENING COLD FRONT WILL
CONTINUE TO LIFT EAST NORTHEAST ACROSS THE WESTERN ATLANTIC
ATLANTIC TODAY THROUGH MONDAY. THIS OVERALL PATTERN WILL INDUCE
WEAK TROUGHINESS WHICH SHOULD FLATTEN JUST NORTH OF THE REGION
OVER THE NEXT FEW DAYS...AS ANOTHER AREA OF HIGH PRESSURE WILL
EXIT THE EASTERN SEABOARD AND SPREAD ACROSS THE WESTERN ATLANTIC.

&&

.DISCUSSION...MOSTLY SUNNY AND FAIR WEATHER SKIES PREVAILED
ACROSS MUCH OF THE REGION SO FAR TODAY AS THE OVERALL ZONAL FLOW
ALOFT ALONG WITH STABLE AND DRY CONDITIONS CONTINUED TO LIMIT
CONVECTIVE DEVELOPMENT. HOWEVER STILL EXPECT POCKETS OF LOW LEVEL
MOISTURE ACROSS THE REGION ALONG WITH LOCAL AND DIURNAL EFFECTS TO
GIVE WAY TO SOME LATE AFTERNOON SHOWERS OF SHORT DURATION OVER
PORTIONS OF THE ISLANDS. SHOWERS OVER PUERTO RICO SHOULD BE FOCUSED
MAINLY OVER PARTS OF THE INTERIOR AND WEST SECTIONS OF THE ISLANDS.
SOME LIGHT SHOWERS MAY CONTINUE TO FORM AND AFFECT PARTS OF THE
U.S. VIRGIN ISLANDS DURING THE REST OF THE AFTERNOON. A GRADUAL
CLEARING CAN BE EXPECTED BY SUNSET AND DURING THE OVERNIGHT HOURS.
BY EARLY MORNING THERE WILL HOWEVER BE A SLIGHT CHANCE OF EARLY
MORNING SHOWERS OVER THE COASTAL WATERS AND THE WINDWARD SECTIONS
OF SOME OF THE ISLANDS.

RECENT MODEL GUIDANCE INITIALIZED FAIRLY WELL AND CONTINUED TO
SUGGEST UPPER LEVEL TROUGH TO APPROACH AND MOVE ACROSS THE REGION
DURING THE EARLY PART OF THE WEEK. THIS WILL ALLOW FOR MORE FAVORABLE
CONDITIONS ALOFT FOR CONVECTIVE DEVELOPMENT AS WELL AS A SLIGHT INCREASE
IN LOW LEVEL MOISTURE CONVERGENCE AT LEAST THROUGH WEDNESDAY. IN ADDITION
THE SUGGESTED MID LEVEL INSTABILITY WILL BE MORE CONDUCIVE FOR FORMATION
OF SHOWERS AND THUNDERSTORMS ACROSS THE REGION. IF THIS PATTERN CONTINUES
TO UNFOLD...THE COMBINATION OF THE AFOREMENTIONED INGREDIENTS WILL INCREASE
THE POTENTIAL FOR SOME ENHANCED SHOWERS AND THUNDERSTORMS OVER THE PORTIONS
OF THE ISLANDS AND COASTAL WATERS AT LEAST UNTIL MID WEEK.

&&

.AVIATION...VFR CONDS THROUGH THE FORECAST PERIOD WITH VCSH EXPECTED
PARTICULARLY AT TJMZ/TJPS AND TJSJ AFTER 10/18Z. WINDS FROM THE EAST
WITH SEA BREEZE VARIATIONS AT AROUND 10-15KTS WITH OCCASIONAL GUSTS
FOR THE REST OF TODAY. DECREASING WINDS TO 5-10KT AFTER 11/00Z BUT
REMAINING EASTERLY. OVERNIGHT VCSH POSSIBLE AT MOST OF THE LOCAL
TERMINALS EXCEPT TJMZ. NO SIGNIFICANT HAZARDS ARE EXPECTED.

&&

.MARINE...RECENT DATA AND OBSERVATION FROM THE SURROUNDING BUOYS
SUGGEST SEAS OF 5 FEET OR LESS ACROSS THE LOCAL WATERS. EXPECTED
THESE CONDITIONS TO CONTINUE DURING THE OVERNIGHT HOURS. A MODERATE
RISK OF RIP CURRENTS ACROSS MOST OF OUR LOCAL COASTLINES DURING
THE REST OF TODAY THROUGH EARLY MONDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 87 74 86 / 30 40 40 40
STT 74 85 73 85 / 30 30 40 40

[HurricaneFan]

So any rough idea how much inches of Rain the Northern Leeward Islands is going to get from Mon to Wed according to the forecast?

[cycloneye]

So any rough idea how much inches of Rain the Northern Leeward Islands is going to get from Mon to Wed according to the forecast?

Some heavy rain is possible but no estimates how will all end.

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
528 AM AST MON APR 11 2016

.SYNOPSIS...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE WESTERN
ATLANTIC...THEN APPROACHES AND MOVES ACROSS THE LOCAL AREA TODAY
THROUGH TUESDAY. THIS OVERALL PATTERN WILL INDUCE WEAK TROUGHINESS
WHICH SHOULD FLATTEN JUST NORTH OF THE REGION OVER THE NEXT FEW
DAYS...AS ANOTHER AREA OF HIGH PRESSURE WILL EXIT THE EASTERN
SEABOARD AND SPREAD ACROSS THE WESTERN ATLANTIC.

&&

.DISCUSSION...ISOLATED TO SCATTERED SHOWERS WERE OBSERVED ACROSS
THE LOCAL WATERS. THESE SHOWERS WERE TRANSPORTED BY THE TRADE
WINDS. AT THE SURFACE...LOCAL AREA WILL REMAIN UNDER THE
INFLUENCE OF AN INDUCE TROUGH...WHICH WILL ENHANCE THE SHOWER AND
THUNDERSTORM ACTIVITY ACROSS THE AREA. SHOWER ACTIVITY WILL BE
ENHANCE BY LOCAL EFFECTS...MAINLY THIS AFTERNOON OVER THE
INTERIOR SECTION OF PUERTO RICO. NEXT FEW DAYS LOCAL AREA WILL BE
DOMINATED BY AN UPPER LEVEL TROUGH WHICH COMBINED WITH THE INDUCE
TROUGH AT THE SURFACE...WILL KEEP GOOD CHANCES FOR SHOWER ACTIVITY
ACROSS THE REGION.

STEERING WIND FLOW IS EXPECTED TO COLLAPSE BY MID WEEK. AS A
RESULT...ANY SHOWER AND THUNDERSTORM ACTIVITY THAT DEVELOPS OVER
THE REGION...WILL REMAIN NEARLY STATIONARY. THEREFORE...THE
POTENTIAL FOR SOME URBAN AND SMALL STREAM FLOODING WILL INCREASE
BY MID WEEK.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. VCSH EARLY IN THE MORNING IN QUICK PASSING SHRA AFFECTING
THE VICINITY OF TJSJ...THE USVI AND THE LEEWARDS TAF SITES. WINDS
WILL PREVAIL MOSTLY FROM THE EAST AT AROUND 10KT OVERNIGHT
INCREASING TO 10 TO 15 KNOTS AFTER 11/13Z. SHRA AND POSSIBLE TSRA
EXPECTED AFTER 10/18Z...AFFECTING THE VICINITY OF TJMZ/TJBQ AND
POSSIBLE TJSJ.

&&

.MARINE...SEAS UP TO 6 FEET AND WINDS UP TO 20 KNOTS ARE EXPECTED
OVER THE COASTAL WATERS. SMALL CRAFT SHOULD EXERCISE CAUTION
ACROSS THE ATLANTIC WATERS AND THE ANEGADA PASSAGE.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 75 85 76 / 40 40 40 40
STT 84 75 85 75 / 30 40 40 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
202 PM AST MON APR 11 2016

.SYNOPSIS...SHOWERS AND THUNDERSTORMS EXPECTED THIS AFTERNOON
ACROSS THE LOCAL AREA AND ARE POSSIBLE ONCE AGAIN ON TUESDAY AND
WEDNESDAY AFTERNOON GIVEN THE CURRENT WEATHER PATTERN OF MOISTURE
INCREASING AND AN UPPER TROUGH MOVING THROUGH THE WESTERN ATLANTIC.
PASSING BRIEF SHOWERS ACROSS THE LOCAL AREA IN THE OVERNIGHT AND
MORNING HOURS.

&&

.DISCUSSION...THE CURRENT AND EXPECTED SYNOPTIC PATTERN CONTINUES
TO INDICATE THAT THE COMBINATION OF THE UPPER LEVEL DYNAMICS AND
THE INCREASE IN MOISTURE WILL RESULT IN AN INCREASE IN SHOWER AND
POSSIBLE THUNDERSTORM DEVELOPMENT ACROSS THE LOCAL
AREA...ESPECIALLY ACROSS WESTERN PR WHERE THE SEA BREEZE
CONVERGENCE AND OTHER LOCAL EFFECTS COME INTO PLAY. THIS MEANS
THAT SCATTERED MODERATE TO BRIEFLY HEAVY SHOWERS ACROSS THE LOCAL
WATERS AND ISLANDS ARE EXPECTED THROUGH THE DAY...AND MORE
PERSISTENT SHOWERS IN THE AFTERNOON ESPECIALLY ACROSS THE
INTERIOR AND WESTERN SECTIONS OF PR. THIS PATTERN...FAVORABLE FOR
THUNDERSTORM DEVELOPMENT IS EXPECTED TO PREVAIL ON TUESDAY AS WELL
AND MAYBE INTO WEDNESDAY. HOWEVER THE AVAILABLE MOISTURE STARTS TO
BECOME MORE MODEST ON WEDNESDAY AND THROUGH THE REST OF THE WEEK
AND THE UPPER LEVELS ARE A BIT LESS CONDUCIVE FOR THUNDERSTORM
DEVELOPMENT AFTER WEDNESDAY. THEREFORE WE CAN STILL EXPECT
CONVECTION CAUSING SHOWERS AND BRIEF THUNDERSTORMS FOR THE LATTER
PART OF THE WEEK BUT IT MAY BE MORE DUE TO LOCAL EFFECTS AND
DIURNAL HEATING.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. SHRA AND POSSIBLE TSRA IN THE VICINITY OF TJBQ/TJMZ FROM
18/22Z. VCSH IN THE AFTERNOON AND TONIGHT WITH PASSING SHRA AND
BRIEF GUSTS AFFECTING TJSJ...TIST...TISX...AND POSSIBLY TJPS.
WINDS WILL PREVAIL MOSTLY FROM THE EAST TO AT AROUND 15-20KT BELOW
10KFT.


&&

.MARINE...SEAS WILL BE UP TO 6 FEET TODAY AND TUESDAY...IMPROVING
THEREAFTER...STAYING UP TO OR BELOW 5 FEET FOR THE REST OF THE
WEEK. THERE IS A MODERATE RISK OF RIP CURRENTS TODAY AND EXPECTED
MODERATE RISK FOR THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 85 76 87 / 40 40 40 40
STT 75 85 75 85 / 40 40 40 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
510 AM AST TUE APR 12 2016

.SYNOPSIS...SURFACE TROUGH WILL CONTINUE TO LINGER CLOSE TO THE
AREA...MAINTAINING A WET PATTERN ACROSS THE REGION. HIGH MOISTURE
CONTENT AT THE SURFACE WILL CONTINUE ACROSS THE AREA THROUGH THE
END OF THE WORK WEEK. A DRIER AIR MASS IS EXPECTED BY THE
WEEKEND.

&&

.DISCUSSION...SHOWERS WERE SEEN ACROSS THE COASTAL WATERS
OVERNIGHT...WITH OTHERS AFFECTING THE NORTHEAST SECTION OF PUERTO
RICO. A LINE OF SHOWERS AND POSSIBLE THUNDERSTORMS EXTENDING FROM
THE NORTHEAST COAST OF PUERTO RICO...THROUGH FEW HUNDRED MILES
INTO THE OCEAN...WAS PRIMARILY ASSOCIATED WITH A SURFACE LOW
PRESSURE AREA AND ITS ASSOCIATED TROUGH. THESE FEATURES WILL
COMBINE ONCE AGAIN THIS AFTERNOON...TO PRODUCE SCATTERED TO
NUMEROUS SHOWERS WITH ISOLATED THUNDERSTORMS OVER THE WESTERN
INTERIOR AND WEST SECTION OF PUERTO RICO.

A DRIER AIR MASS IS EXPECTED TO ENCOMPASS THE LOCAL REGION BY THE
END OF THE WORK WEEK...AS AN UPPER LEVEL RIDGE BUILDS ACROSS THE
AREA. HOWEVER...SOME AFTERNOON CONVECTION IS EXPECTED TO DEVELOP
AS LOW LEVEL MOISTURE AND A LIGHT STEERING WIND FLOW REMAINS OVER
THE REGION.

&&

.AVIATION...VCSH ARE EXPECTED UNTIL 12/12Z ACROSS THE LOCAL FLYING
AREA. SHRA AND POSSIBLE TSRA ARE EXPECTED TO DEVELOP ACROSS THE
LEEWARDS AND USVI TAF SITES AFTER 12/12Z WITH VCSH ELSEWHERE ACROSS
THE REGION. AFTER 12/16Z SHRA/TSRA WILL DEVELOP IN THE VICINITY OF
TJBQ/TJMZ AND TJSJ. WINDS WILL PREVAIL MOSTLY FROM THE EAST AT
AROUND 10 MPH OVERNIGHT...INCREASING TO 10 TO 15 AFTER 12/14Z WITH
HIGHER GUSTS NEAR SHOWERS AND THUNDERSTORMS.

&&

.MARINE...SEAS UP TO 6 FEET AND WINDS UP TO 20 KNOTS ARE EXPECTED
OVER THE COASTAL WATERS. SMALL CRAFT SHOULD EXERCISE CAUTION
ACROSS THE OFFSHORE ATLANTIC WATERS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 76 88 77 / 40 40 40 20
STT 85 76 85 74 / 40 40 40 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
210 PM AST TUE APR 12 2016

.SYNOPSIS...TROUGHINESS ALOFT WILL CONTINUE AT LEAST THROUGH THE
END OF THE WEEK. INDUCED WEAK SURFACE TROUGH WILL CONTINUE NE OF
THE AREA. SUBSIDENCE INVERSION AROUND 750 MB EXPECTED THURSDAY
ONWARDS. MAINLY LIGHT AND VARIABLE WINDS EXPECTED FOR THE NEXT FEW
DAYS...WITH A LIGHT NORTHERLY STEERING WIND COMPONENT.


&&

.DISCUSSION...NUMEROUS SHOWERS WITH THUNDERSTORMS WERE OBSERVED
TODAY ACROSS PR AND ACROSS THE REGIONAL WATERS...AS UPPER LEVEL
TROUGH ENHANCED THE DIURNAL CONVECTION ACROSS THE CORDILLERA
CENTRAL AND WITH A WESTERLY STEERING WIND PUSHED THE SHOWERS AND
THUNDERSTORMS ACROSS THE EASTERN HALF OF THE ISLAND. AS OF 2 PM
AST...MAX RAINFALL AMOUNTS REPORTED BY RAINGAGES WERE IN THE 1 TO
2 INCHES RANGE FROM PONCE TO AGUAS BUENAS. URBAN FLOODING AND
LIGHTNING STRIKES WERE REPORTED BY WEATHER OBSERVERS AND MEDIA
ACROSS THE EAST/SOUTHEAST SECTIONS OF MAINLAND PR. MID LEVEL
DRIER AIR WILL FILL IN LATER DURING THE OVERNIGHT HOURS...WITH
BEST MOISTURE HANGING OVER THE CARIBBEAN WATERS/ANEGADA PASSAGE
AND THE USVI/EASTERN PR FORECAST AREA. THEREFORE...ANY ADDITIONAL
SHOWER ACTIVITY ACROSS THESE AREAS WILL LIKELY CAUSE URBAN AND
SMALL STREAM FLOODING.

AS TROUGH PATTERN REMAINS ALOFT...SHOWER AND THUNDERSTORM ACTIVITY CANT
BE RULED OUT ACROSS THE CORDILLERA CENTRAL EACH DAY THROUGH AT
LEAST THURSDAY. AS SUBSIDENCE INVERSION BUILDS...BEST MOISTURE
WILL REMAIN BELOW 700-750 MB...AND WITH A LIGHT NORTHERLY
STEERING WIND FLOW THE DIURNAL CONVECTION WILL FAVOR THE WESTERN INTERIOR
AND SOUTHERN/EASTERN COASTAL AREAS OF THE ISLANDS. FAIR WEATHER
RETURNS BY THE END OF THE WEEK...UNTIL ANOTHER WET PATTERN
ESTABLISH BY EARLY NEXT WEEK AS DEEP TROPICAL MOISTURE INCREASES
FROM THE WINDWARD ISLANDS AND CARIBBEAN WATERS. THIS SEEMS TO BE
ASSOCIATED TO THE MERGING OF THE SURFACE TROUGH NE OF THE ISLANDS
WITH A COLD FRONT EXITING THE U.S. EAST COAST.

&&

.AVIATION...PREVAILING VFR...BUT SHRA/TSRA WILL CONT TO DEVELOP
VCNTY OF TJSJ...TJBQ... TJPS...TJMZ. WINDS MAINLY FM E 10-15 KTS
W/HIGHER GUSTS TIL 12/23Z. BKN-OVC LYS FL025...FL040..FL080...MAX
TOPS W/ISOLD TSRA 250-300 KFT OVER FLYING AREA ATTM. LOCAL
ASSESSMENT TOOL AND WX CONDS SUGGEST PSBL WATERSPOUTS BTW PR AND NRN
LEEWARDS.

&&

.MARINE...SEAS SHOULD REMAIN BELOW 6 FEET FOR THE NEXT FEW DAYS
ACROSS ALL LOCAL WATERS WITH VARIABLE WINDS BELOW 10 KNOTS. A
SMALL NE GROUND SWELL IS EXPECTED TO REACH THE LOCAL WATERS ON
FRIDAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 87 77 83 / 40 40 20 20
STT 76 85 74 78 / 40 40 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
502 AM AST WED APR 13 2016

.SYNOPSIS...UPPER LEVEL TROUGH OVER THE REGION WILL CONTINUE TO MOVE
EASTWARD AWAY FROM THE LOCAL ISLANDS THROUGH TONIGHT. AS A
RESULT...SHOWER ACTIVITY WILL GRADUALLY DECREASE ACROSS THE
ISLANDS OVER THE NEXT 24 HRS. A DRIER AIR MASS WILL ENCOMPASS THE
REGION AT THE END OF THE WORK WEEK. A RETURN TO A WETTER PATTERN
IS EXPECTED BY EARLY NEXT WEEK.

&&

.DISCUSSION...ISOLATED TO SCATTERED SHOWERS WERE OBSERVED MAINLY
ACROSS THE COASTAL WATERS. SOME LIGHT SHOWERS WERE APPROACHING THE
NORTH COAST OF PUERTO RICO FROM THE ATLANTIC WATERS EARLY THIS
MORNING. OTHER SHOWERS WERE IN THE VICINITY OF THE US VIRGIN
ISLANDS. LOCAL AREA REMAINS UNDER THE INFLUENCES OF AN UPPER LEVEL
TROUGH. THIS TROUGH WILL MOVE AWAY FROM THE REGION TODAY.
THEREFORE...SHOWER ACTIVITY WILL BE LIMITED COMPARED TO YESTERDAY.
HOWEVER...SHOWERS ARE EXPECTED TO DEVELOP ONCE AGAIN THIS
AFTERNOON MAINLY ALONG THE CORDILLERA CENTRAL OF PUERTO RICO.

FOR THE REMAINDER OF THE WEEK...A DRIER AIR MASS WILL ENCOMPASS
THE REGION...WHICH WILL LIMIT EVEN MORE THE CHANCE FOR SHOWERS
ACROSS THE REGION. IT IS NOT UNTIL EARLY NEXT WEEK...MOISTURE
WILL INCREASE AGAIN AS AN UPPER LEVEL TROUGH DEVELOPS CLOSE TO THE
REGION.

&&

.AVIATION...PASSING SHOWERS STILL POSSIBLE AT THE LEEWARD...USVI AND
JSJ TERMINALS THROUGH THE MORNING HOURS. AFT 13/16Z...PERIODS OF
MVFR CONS AND MOUNTAIN OBSCURATIONS IN SHRA/TSRA EXPECTED AT JMZ/JPS
AND POSSIBLY JSJ THROUGH 13/22Z. LIGHT AND VARIABLE WINDS WILL
CONTINUE TO PREVAIL ACROSS LOCAL TERMINALS.

&&

.MARINE...SEAS WILL SLOWLY SUBSIDE ACROSS THE LOCAL REGION THROUGH
FRIDAY MORNING. WINDS WILL BE MAINLY LIGHT AND VARIABLE THROUGH
THE END OF THE WEEK. SEAS ARE EXPECTED TO REACH 2-4 FEET BETWEEN
THURSDAY MORNING AND FRIDAY MORNING. THEN...A SMALL NE SWELL WILL
INCREASE SLIGHTLY THE SEAS ON FRIDAY AFTERNOON. ANOTHER SWELL FROM
THE NORTH WILL LIKELY BUILD THE SEAS TO 5-7 FT ON MONDAY. NO SMALL
CRAFT ADVISORIES ARE ANTICIPATED THE REST OF THE WEEK.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 75 88 76 / 40 20 20 20
STT 86 75 85 73 / 40 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
147 PM AST WED APR 13 2016

.SYNOPSIS...AT UPPER LEVELS...A WEAK TROUGH WILL MOVE THROUGH THE
AREA TONIGHT AND THURSDAY MORNING...THEN A RIDGE WILL MOVE ACROSS
WHILE WEAKENING. A STRONG JET IS EXPECTED TO CONTINUE JUST NORTH
OF THE AREA FOR AT LEAST THE NEXT 7 DAYS.

AT MID LEVELS...WEAK TROUGHINESS WILL REMAIN OVER OR JUST UPSTREAM
FROM THE LOCAL AREA THROUGH MID WEEK NEXT WEEK. MID LEVELS WILL
REMAIN DRY UNTIL EARLY NEXT WEEK. CURRENT GFS FORECASTS DEEP
MOISTURE BEGINNING EARLY NEXT WEEK.

AT LOWER LEVELS...WEAK LOW PRESSURE ABOUT 270 NM NORTH NORTHEAST
OF THE AREA WILL MOVE NORTHEAST LEAVING LIGHT NORTHERLY WINDS
UNTIL FRIDAY. THIS LOW WILL ARC UP TOWARD THE NORTHWEST AND JOIN
ANOTHER LOW FORMING IN THE WESTERN ATLANTIC MAINTAINING GENTLE
WINDS ACROSS THE AREA THAT WILL BECOME MORE SOUTHEASTERLY NEXT
WEEK. LOW LEVEL MOISTURE PERSISTS...BUT REMAINS SHALLOW UNTIL
MONDAY.

&&

.DISCUSSION...A FEW VERY LIGHT SHOWERS ARE APPEARING ON THE FLANKS
OF EL YUNQUE AND OVER THE CORDILLERA CENTRAL...BUT ONLY MINOR
CONVECTION IF ANY IS EXPECTED OVER LAND TODAY AND TONIGHT. IN THE
U.S. VIRGIN ISLANDS LOCAL CONVECTION INITIATED OVER SAINT CROIX IN
THE CONVERGENCE OVER THE ISLAND AFTER NOON...BUT SHOULD NOT
PERSIST FOR VERY LONG. WINDS ARE LIGHT AND IT IS NOT EXPECTED TO
MOVE MUCH. TONIGHT SHOWERS MAY MOVE OVER PUERTO RICO IN THE LIGHT
FLOW FROM THE NORTH...BUT LAND BREEZES COULD EASILY HOLD OVER THE
LOCAL WATERS WHAT FEW SHOWERS WOULD HAVE APPROACHED. ALTHOUGH
PERHAPS NOT SO LIGHT...THESE SHOWERS ARE NOT EXPECTED TO PERSIST
LONG AND WILL HAVE TO DEVELOP IN SHALLOW MOISTURE. MODELS SEEM
MORE OPTIMISTIC THAT SHOWERS WILL FORM AS SEA BREEZES DEVELOP
TOMORROW DURING THE DAY...BUT THE CENTER OF THE ACTIVITY WILL
AGAIN BE OVER THE CORDILLERA CENTRAL AND MAY EVEN FAVOR EASTERN
PUERTO RICO.

THE GFS CONTINUES TO SHOW DEEP MOISTURE ARRIVING ON SOUTHWESTERLY
FLOW OUT OF SOUTH AMERICA MONDAY MORNING. IF THE MODELS ARE
CORRECT THIS SHOULD BE A SIGNIFICANT EVENT AND MAY REPRESENT THE
FIRST REAL FLOODING THREAT IN MANY MONTHS. ALTHOUGH MOISTURE
PERSISTS DURING THE WEEK THE LOCAL FORECAST AREA DOES NOT REMAIN
UNDER THE CORE OF THE BEST DYNAMICS OR THE BEST MOISTURE AND THE
THREAT OF HEAVY RAIN SHOULD END ON WEDNESDAY. INTERESTED PARTIES
SHOULD CONTINUE TO MONITOR THE DEVELOPMENT OF THIS FLOW.

&&

.AVIATION...MAINLY VFR CONDITIONS EXPECTED ACROSS ALL TERMINALS
DURING THE NEXT 24 HOURS. HOWEVER...AFTERNOON SHRA STILL EXPECTED TO
DEVELOP OVER THE CENTRAL MTN RANGES AND COULD BRIEFLY AFFECT TJPS.
ALSO...DIURNALLY INDUCED SHRA ACROSS THE FLYING AREA OF TISX
EXPECTED TO DIMINISH BY 22Z. -SHRA COULD BRIEFLY AFFECT THE FLYING
AREA BETWEEN THE USVI/EASTERN PR DURING THE OVERNIGHT HOURS. LIGHT
AND VARIABLE WINDS EXPECTED OVERNIGHT...INCREASING TO AROUND 10 KT
FROM THE NORTH AFTER 14/14Z.

&&

.MARINE...A RAPIDLY DEVELOPING LOW PRESSURE IN THE ATLANTIC WILL
BRING 5 TO 6 FOOT SWELL TO THE AREA BY MONDAY. SMALL CRAFT
ADVISORIES ARE EXPECTED THEN. LIGHT WINDS IN THE LOCAL AREA THOUGH
SHOULD KEEP SEAS RELATIVELY TRANQUIL UNTIL THEN.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 86 75 88 / 20 20 20 20
STT 76 84 76 85 / 10 10 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
524 AM AST THU APR 14 2016

.SYNOPSIS...DRIER AIR MOVING IN AND LIGHT WINDS WILL LEAD TO
MOSTLY LOCALLY INDUCED SHOWERS ACROSS PUERTO RICO IN THE
AFTERNOON AS DAYTIME HEATING AND SEA BREEZE CONVERGENCE COMBINE.
THE USVI WILL REMAIN MAINLY DRY WITH ONLY A SLIGHT CHANCE OF
SHOWERS AS AIR INTERACTS WITH THE OROGRAPHY. THIS RELATIVELY DRY
PATTERN IS EXPECTED THROUGH THE UPCOMING WEEKEND.

&&

.DISCUSSION...SURFACE LOW TO THE NORTHEAST OF THE LOCAL AREA WILL
KEEP WINDS FAIRLY LIGHT AND FROM THE NORTH ACROSS THE LOCAL AREA.
THIS WILL ALLOW FOR SEA BREEZE TO DEVELOP OVER PR AND THE SHOWER
PROBABILITY WILL INCREASE IN THOSE AREAS OF SEA BREEZE
CONVERGENCE. THE UPPER LEVELS DO NOT LOOK PARTICULARLY CONDUCIVE
TO SUPPORT LONG LASTING SHOWERS AND THUNDERSTORMS. THIS GENERAL
PATTERN IS EXPECTED TO PREVAIL THROUGH THE WEEKEND. HOWEVER...THE
WINDS WILL SHIFT TO A MORE EASTERLY DIRECTION STARTING LATE
SATURDAY INTO SUNDAY...BUT THEY SHOULD STILL BE FAIRLY LIGHT.

THE MORE INTERESTING SCENARIO REALLY STARTS EARLY NEXT WEEK.
ALTHOUGH IT MIGHT BE A BIT TOO FAR TO HAVE CONSIDERABLE
CONFIDENCE...THE LATEST GUIDANCE SUGGESTS THAT THE AVAILABLE
MOISTURE WILL INCREASE SIGNIFICANTLY STARTING ON MONDAY AS A
STRONG SURFACE LOW ESTABLISHES TO THE NORTH OF THE LOCAL AREA.
PRECIPITABLE WATER MAY REACH 2 INCHES ON MONDAY ACCORDING TO
GUIDANCE. THERE IS ALSO AN UPPER LOW THAT WILL BE TO THE NORTH OF
THE AREA WITH AN ASSOCIATED TROUGH WHOSE AXIS WILL BE JUST WEST OF
THE LOCAL ISLANDS FOR LATE MONDAY AND TUESDAY. THIS WILL CAUSE AN
INCREASE IN INSTABILITY AND LIKELY AN INCREASE IN SHOWERS AND
THUNDERSTORMS ACROSS THE LOCAL ISLANDS.

THE ENHANCED MOISTURE APPEARS TO STAY WITH US JUST ABOUT THE
ENTIRE WORKWEEK...WHICH MEANS THAT ONCE THE UPPER TROUGH LEAVES
THE AREA BY WEDNESDAY...LOCALLY INDUCED SHOWERS AND POSSIBLE
THUNDERSTORMS COULD CAUSE SIGNIFICANT RAINFALL AMOUNTS. SHOWERS
AND THUNDERSTORMS THROUGH THE LOCAL ISLANDS WILL BE VERY PROBABLE
IF THE MODELS WERE TO BE CORRECT.

&&

.AVIATION...LIGHT WINDS AND VFR CONDS EXPECTED TODAY. VCSH
POSSIBLE AT TJPS AND TJSJ IN THE AFTERNOON. THE LIGHT WINDS WILL
PREVAIL FROM THE NORTH AT ABOUT 5-10KT AND THEN SEA BREEZE
VARIATIONS WILL DEVELOP AFTER 14/13Z.


&&

.MARINE...MODERATE RISK OF RIP CURRENTS IS EXPECTED ACROSS THE
NORTH COAST OF PUERTO RICO TODAY. SEAS WILL BE UP TO 4 FEET
ACROSS THE LOCAL WATERS TODAY AND TONIGHT.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 76 88 76 / 10 20 20 20
STT 87 75 84 72 / 20 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
217 PM AST THU APR 14 2016

.SYNOPSIS...BROAD UPPER TROUGH WILL CONTINUE OVER THE WESTERN ATLANTIC
AND NORTHERN CARIBBEAN INTO THE UPCOMING WEEKEND. A FEW WEAK MID LEVEL
SHORT WAVES WILL MOVE ALONG THE BASE OF THIS TROUGH JUST NORTH OF
THE REGION OVER THE NEXT COUPLE OF DAYS. HOWEVER...THIS SHOULD HAVE
LITTLE OR NO EFFECT ON THE LOCAL AREA AS MID LEVEL CAP INVERSION
WILL HOLD ACROSS THE REGION TO SUPPRESS AND LIMIT CONVECTIVE DEVELOPMENT.
IN ADDITION...A VERY DRY AIRMASS WILL PERSIST ACROSS THE AREA THROUGH
THE WEEKEND. AT LOW LEVELS... SURFACE LOW WELL NORTHEAST OF THE
REGION... ALONG WITH HIGH PRESSURE RIDGE SPREADING ACROSS THE SOUTHWEST
ATLANTIC WILL MAINTAIN VERY LIGHT NORTHERLY WINDS THROUGH FRIDAY.
THE LOW IS TO GRADUALLY LIFT FARTHER NORTHEAST BY FRIDAY...AS A WEAK
HIGH PRESSURE RIDGE WILL SPREAD ACROSS THE AREA FORM THE WESTERN ATLANTIC.
THIS WILL HELP CREATE LIGHT TO MODERATE EAST TO SOUTHEAST WIND FLOW
OVER THE WEEKEND.

&&

.DISCUSSION...THE WEAK MID LEVEL CAP INVERSION AND OVERALL DRY
WEATHER PATTERN WITH NO MOISTURE ADVECTION LEAD TO MOSTLY FAIR
WEATHER AND STABLE CONDITIONS TODAY . EXPECT THESES CONDITIONS TO
PERSIST ON FRIDAY AND INTO THE WEEKEND. WINDS WILL HOWEVER BECOME
MORE EAST SOUTHEAST RESULTING IN SOME SHALLOW MOISTURE ADVECTION
OVER PORTIONS FOR THE FORECAST AREA. THEREFORE WITH THE LIGHT WIND
FLOW AND LIMITED MOISTURE AVAILABILITY EXPECT ONLY A FEW LOCALLY
AND DIURNALLY INDUCED SHOWERS. THIS ACTIVITY SHOULD BE MAINLY
FOCUSED ALONG PARTS OF THE CENTRAL AND SOUTHERN MOUNTAIN RANGE
THROUGH MOST OF THE WEEKEND. MOSTLY FAIR WEATHER CONDITION WILL
THEREFORE PREVAIL.

BY EARLY NEXT WEEK...THE OVERALL PATTERN IS FORECAST TO CHANGE
SIGNIFICANTLY...AS THE THE MID TO UPPER LEVEL TROUGH NORTH OF THE
REGION DEEPENS AND BECOMES AMPLIFIED OVER THE REGION. THIS IN TURN
WILL ALLOW GOOD LOW LEVEL MOISTURE CONVERGENCE AND INCREASING POTENTIAL
FOR SHOWER AND THUNDERSTORM DEVELOPMENT. FOR NOW AND BASED ON RECENT
MODEL GUIDANCE...AT LEAST DURING THE EARLY PART OF NEXT WEEK AND
POSSIBLE FOR MOST OF THE WEEK EXPECT A MUCH WETTER WEATHER PATTERN
FOR THE LOCAL ISLANDS.

&&

.AVIATION...MAINLY VFR CONDITIONS EXPECTED ACROSS ALL TERMINALS
DURING THE NEXT 24 HOURS. LIGHT AND VARIABLE WINDS EXPECTED
OVERNIGHT...INCREASING TO AROUND 10 KT FROM THE NORTH-NORTHWEST
AFTER 15/13Z.

&&

.MARINE...BUOYS ACROSS THE LOCAL ISLANDS CONTINUE TO SUGGEST SEAS
BELOW 3 FEET AND NNW WINDS LESS THAN 10 KNOTS. SMALL LONG PERIOD
NE GROUND SWELL ARE FORECAST TO REACH THE LOCAL ATLANTIC WATERS
AND PASSAGES BY FRIDAY MORNING. MODERATE RISK OF RIP CURRENTS
CONTINUE ALONG THE NORTHERN BEACHES OF PR...CULEBRA AND ST. CROIX
DURING THE REST OF THE DAY AND OVERNIGHT.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 88 76 88 / 20 20 20 20
STT 75 84 72 84 / 20 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
432 AM AST FRI APR 15 2016

.SYNOPSIS...A MID LEVEL CAP INVERSION WILL HOLD THROUGH THE
WEEKEND. A MID TO UPPER LEVEL TROUGH WILL THEN BECOME THE
DOMINANT WEATHER FEATURE...BRINGING WETTER CONDITIONS TO THE
LOCAL ISLANDS EARLY NEXT WEEK. LIGHT WINDS WILL CONTINUE TO
PREVAIL ACROSS THE FORECAST AREA.

&&

.DISCUSSION...RAIN-FREE CONDITIONS OVER LAND AREAS AND MOSTLY
CLEAR SKIES PREVAILED OVERNIGHT AND EARLY THIS MORNING. THE
COASTAL TEMPERATURES WERE IN THE LOW TO MID 70S AND WINDS WERE
LIGHT AND VARIABLE.

UNDER A MID LEVEL CAP INVERSION AND LIMITED LOW LEVEL MOISTURE...
CONTINUE TO EXPECT FAIR WEATHER CONDITIONS WITH LOCALLY INDUCED
SHOWERS EACH AFTERNOON. AFTERNOON SHOWERS WILL BE FOCUSED ACROSS
THE INTERIOR OF PUERTO RICO DURING THE WEEKEND... BUT TODAY ARE
EXPECTED TOWARD THE SOUTHEAST QUADRANT OF THE ISLAND.

A BROAD MID TO UPPER LEVEL TROUGH WILL THEN ESTABLISH ACROSS THE
WESTERN ATLANTIC AND INTO THE NORTHERN CARIBBEAN EARLY NEXT WEEK.
AS THE CAP WEAKENS AND THE TROUGH ESTABLISHES...DEEP TROPICAL
MOISTURE IS EXPECTED TO ADVECT ACROSS THE EASTERN CARIBBEAN FROM
THE SOUTHEAST MONDAY...AND CONTINUE THROUGH THE END OF THE WORK
WEEK. ALTHOUGH BEST MOISTURE CONVERGENCE IS STILL EXPECTED MAINLY
EAST SOUTHEAST OF THE AREA...ENOUGH MOISTURE IS EXPECTED TO ADVECT
ACROSS THE FORECAST AREA. BASED ON LATEST GUIDANCE...UNDER TROUGH
ALOFT WITH ASSOCIATED FAVORABLE JET DYNAMICS AS WELL AS PLENTY OF
LOW LEVEL MOISTURE...THERE IS HIGH POTENTIAL FOR HEAVY/PERSISTENT
CONVECTION MONDAY AFTERNOON AND TUESDAY.

ALTHOUGH MOISTURE WILL CONTINUE TO PERSIST MUCH OF THE WEEK...THERE
IS A LACK OF DYNAMICS AS THE TROUGH MOVES AWAY ON WEDNESDAY. THEREFORE...
WEDNESDAY THROUGH THE END OF THE WEEK...LOCALLY INDUCED CONVECTION
WILL PREVAIL AS A RESULT OF AVAILABLE MOISTURE...DIURNAL HEATING
AND LOCAL EFFECTS. CONTINUE TO MONITOR THE EVOLUTION OF THIS
PATTERN.

&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS ALL TERMINALS DURING
THE NEXT 24 HOURS. LIGHT AND VARIABLE WINDS EXPECTED UNTIL 15/13Z.
WINDS WILL THEN INCREASE A LITTLE TO 5-10KT BUT DIRECTION WILL
VARY BY LOCATION WITH A STRONG SEA BREEZE INFLUENCE. LITTLE TO NO
SHRA EXPECTED THROUGH THE FORECAST PERIOD.

&&

.MARINE...RELATIVELY TRANQUIL MARINE CONDITIONS WILL CONTINUE
ACROSS THE REGIONAL WATERS OVER THE NEXT FEW DAYS WITH SEAS UP
TO 4 FEET AND WINDS AROUND 10 KNOTS. A SMALL SWELL WILL REACH
THE LOCAL WATERS TODAY INCREASING THE RIP CURRENT DEVELOPMENT
ACROSS THE NORTH COAST OF THE ISLANDS FROM TIME TO TIME. A LARGE
LONG PERIOD NNE SWELL IS FORECAST TO AFFECT THE ATLANTIC WATERS
ON MONDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 77 87 77 / 20 10 10 20
STT 88 76 87 76 / 20 10 10 20