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000
FXCA62 TJSJ 290128
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
928 PM AST THU APR 28 2016

.UPDATE...SHOWERS AND THUNDERSTORMS WERE OBSERVED IN THE AFTERNOON
ACROSS WESTERN PR. SOME OF THE THUNDERSTORMS PRODUCED INTENSE
LIGHTNING AND THE SHOWERS WERE LOCALLY HEAVY...PRODUCING SOME
URBAN AND SMALL STREAM FLOODING. THIS WAS DUE TO THE AVAILABLE
MOISTURE AND THE UNSTABLE ATMOSPHERE.

REGARDING THE UPCOMING WEATHER...THE NAAPS AEROSOL MODEL INDICATES
THAT WE MAY STILL HAVE SOME SAHARAN DUST FOR THE NEXT DAY OR
TWO...SIMILAR TO WHAT WE HAVE HAD IN THE PAST COUPLE OF DAYS. AS
FAR AS WEATHER GOES...THE OVERALL PATTERN IS EXPECTED TO BE VERY
SIMILAR TOMORROW SINCE THE AVAILABLE MOISTURE AND UPPER AIR
PATTERN CONTINUES TO BE FAVORABLE FOR SHOWER AND THUNDERSTORM
DEVELOPMENT. IN THE SURFACE THOUGH...THERE APPEARS TO BE A SHORT
WAVE TROUGH THAT WILL APPROACH THE LOCAL AREA TOMORROW AFTERNOON
THEN THERE IS THE THETA-E VALUES WHICH ARE INDICATIVE OF ENOUGH
INSTABILITY FOR THE DEVELOPMENT OF THUNDERSTORMS...WHICH ALSO
CONCURS WITH THE FORECAST SOUNDINGS. SO WE DO EXPECT SHOWERS AND
THUNDERSTORMS ON FRIDAY ACROSS THE LOCAL AREA. THE HIGH RESOLUTION
MODELS SEEM TO FAVOR THE INTERIOR...NORTH CENTRAL...AND THE
WESTERN HALF OF PR AS WE WOULD HAVE A LIGHT SOUTHEASTERLY WIND
FLOW. THE IMPACT WILL BE AT LEAST SOME URBAN AND SMALL STREAM
FLOODING.

&&

.AVIATION...VFR CONDS LIKELY CONTINUE AT ALL TAF SITES THRU THE
OVERNIGHT HOURS. HOWEVER...MVFR CONDS WILL REMAIN POSSIBLE ONCE
AGAIN AT TJMZ/TJBQ AND POSSIBLY TJSJ TERMINALS IN SHRA/TSRA BETWEEN
17Z AND 22Z. MOUNTAIN OBSCURATION EXPECTED ACROSS THE INTERIOR OF
PR FRI AFTERNOON. LOW LEVEL WINDS 5-15 KT FROM THE SE...BECOMING
LIGHT AND VARIABLE OVERNIGHT.

&&

.MARINE...SMALL CRAFT SHOULD EXERCISE CAUTION AS SEAS WILL BE UP
TO 6 FEET ACROSS THE ATLANTIC OFFSHORE WATERS TONIGHT AND FRIDAY.
NORTHERLY SWELL IS SUBSIDING AND THE SURF HEIGHTS HAVE ALSO
DIMINISHED SO THERE IS NOW A MODERATE RISK OF RIP CURRENTS ACROSS
THE ATLANTIC COASTS OF THE LOCAL ISLANDS.


&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...A BROAD UPPER LEVEL TROUGH ACROSS THE WESTERN
ATLANTIC TO THE NORTHERN CARIBBEAN WILL CONTINUE TO MAINTAIN A
DIVERGENT PATTERN ACROSS THE FORECAST AREA DURING THE NEXT SEVERAL
DAYS...AS UPPER LEVEL PERTURBATIONS MOVE OVER THE ISLANDS FROM
TIME TO TIME. AT LOWER LEVELS...INDUCED SURFACE TROUGH ACROSS
THE WATERS NORTH OF HISPANIOLA AND SURFACE HIGH TO THE NORTHEAST
OF THE REGION WILL PROMOTE A SOUTHEASTERLY WIND FLOW THROUGH MUCH
OF THE FORECAST PERIOD. SAHARAN DUST WILL CONTINUE ACROSS THE AREA
AT LEAST UNTIL SATURDAY.

DISCUSSION...THROUGH THE MORNING HOURS UNTIL NOW...A CLUSTER OF
THUNDERSTORMS HAVE REDEVELOP OVER THE CARIBBEAN WATERS TO THE
SOUTH OF VIEQUES AND ST. CROIX. THIS IS DUE TO THE POSITION OF THE
UPPER TROF AXIS AND A 90+ KT JET ABOVE 200 MB AS INDICATED BY THE
28/12Z TJSJ UPPER AIR SOUNDING. THIS UPPER LEVEL PERTURBATION
WILL CONTINUE TO LIFT TO THE NORTHEAST TODAY...HOWEVER...DIURNALLY
INDUCED AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE ENHANCED BY
FAVORABLE UPPER LEVEL DYNAMICS ACROSS THE MTN RANGES OF PR AND
SLOWLY DRIFT TO THE NORTH-NORTHWEST AS STEERING WINDS PREVAIL
FROM THE SOUTH. ALSO...DRIER AIR BETWEEN 600-500 MB AND LOW
TEMPS(-9.5C) AT 500 MB COULD CREATE SMALL HAIL AND/OR STRONG GUSTY
WINDS AT THE SURFACE WITH THE THUNDERSTORMS THIS AFTERNOON.

TROUGHINESS ALOFT WILL MAINTAIN FAVORABLE CONDITIONS
FOR THE DEVELOPMENT OF SHOWERS AND STRONG THUNDERSTORMS THROUGH
EARLY NEXT WEEK. AS UPPER LEVEL SHORT WAVE VERTICES MOVE ACROSS
THE FORECAST AREA DURING THE WEEKEND AND EARLY NEXT WEEK...THIS
WILL ENHANCE RAINFALL AND THUNDERSTORM ACTIVITY OVER THE INTERIOR
AND THE NORTH/EASTERN SIDE OF THE ISLAND. FRIDAY/SATURDAY SEEMS TO
BE THE NEXT ACTIVE WEATHER DAY WITH DEEPER SHORT WAVE MOVING ALOFT
AND BETTER LOW LEVEL MOISTURE POOLING ACROSS THE AREA. ANOTHER
SHORT WAVE TROF MOVES ON MONDAY ENHANCING CONVECTION ONCE AGAIN.
DUE TO ALREADY SATURATED SOILS...ANY ADDITIONAL HEAVY RAINFALL WILL
LEAD TO URBAN AND SMALL STREAM/RIVER FLOODING. ALSO...LOCALIZED FLASH
FLOODING AND MUDSLIDES CANT BE RULED OUT EACH AFTERNOON.

AVIATION...MVFR CONDS WILL REMAIN POSSIBLE THROUGH AT LEAST 28/22Z
AT TJMZ/TJBQ AND POSSIBLY TJSJ TERMINALS IN SHRA/TSRA. MOUNTAIN
OBSCURATION ACROSS THE INTERIOR OF PR. MOSTLY VFR COND FOR THE REST
OF THE AREA. LOW LEVEL WINDS 5-15 KT FROM THE SE...BECOMING LIGHT
AND VARIABLE OVERNIGHT.

MARINE...LATEST BUOY READINGS INDICATE THAT THE NORTHERLY SWELL
IS SLOWLY FADING AND MODEL GUIDANCE SUGGEST THE SAME WITH
WAVE HEIGHTS AROUND 4 FEET AT 10 SECONDS. SEAS WILL REMAIN
GENERALLY BELOW 6 FEET ACROSS ALL LOCAL WATERS DURING THE NEXT
SEVERAL DAYS. UNSETTLED WEATHER CONDITIONS WILL CONTINUE ACROSS
THE REGIONAL WATERS INTO EARLY NEXT WEEK AS THUNDERSTORMS ARE
FORECAST TO DEVELOP OVER THE WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  88  75  88 /  30  50  40  40
STT  76  83  76  83 /  40  40  40  40

&&

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

$$

11/25





000
FXCA62 TJSJ 281741
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
141 PM AST THU APR 28 2016

.SYNOPSIS...A BROAD UPPER LEVEL TROUGH ACROSS THE WESTERN
ATLANTIC TO THE NORTHERN CARIBBEAN WILL CONTINUE TO MAINTAIN A
DIVERGENT PATTERN ACROSS THE FORECAST AREA DURING THE NEXT SEVERAL
DAYS...AS UPPER LEVEL PERTURBATIONS MOVE OVER THE ISLANDS FROM
TIME TO TIME. AT LOWER LEVELS...INDUCED SURFACE TROUGH ACROSS
THE WATERS NORTH OF HISPANIOLA AND SURFACE HIGH TO THE NORTHEAST
OF THE REGION WILL PROMOTE A SOUTHEASTERLY WIND FLOW THROUGH MUCH
OF THE FORECAST PERIOD. SAHARAN DUST WILL CONTINUE ACROSS THE AREA
AT LEAST UNTIL SATURDAY.

&&

.DISCUSSION...THROUGH THE MORNING HOURS UNTIL NOW...A CLUSTER OF
THUNDERSTORMS HAVE REDEVELOP OVER THE CARIBBEAN WATERS TO THE
SOUTH OF VIEQUES AND ST. CROIX. THIS IS DUE TO THE POSITION OF THE
UPPER TROF AXIS AND A 90+ KT JET ABOVE 200 MB AS INDICATED BY THE
28/12Z TJSJ UPPER AIR SOUNDING. THIS UPPER LEVEL PERTURBATION
WILL CONTINUE TO LIFT TO THE NORTHEAST TODAY...HOWEVER...DIURNALLY
INDUCED AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE ENHANCED BY
FAVORABLE UPPER LEVEL DYNAMICS ACROSS THE MTN RANGES OF PR AND
SLOWLY DRIFT TO THE NORTH-NORTHWEST AS STEERING WINDS PREVAIL
FROM THE SOUTH. ALSO...DRIER AIR BETWEEN 600-500 MB AND LOW
TEMPS(-9.5C) AT 500 MB COULD CREATE SMALL HAIL AND/OR STRONG GUSTY
WINDS AT THE SURFACE WITH THE THUNDERSTORMS THIS AFTERNOON.

TROUGHINESS ALOFT WILL MAINTAIN FAVORABLE CONDITIONS
FOR THE DEVELOPMENT OF SHOWERS AND STRONG THUNDERSTORMS THROUGH
EARLY NEXT WEEK. AS UPPER LEVEL SHORT WAVE VERTICES MOVE ACROSS
THE FORECAST AREA DURING THE WEEKEND AND EARLY NEXT WEEK...THIS
WILL ENHANCE RAINFALL AND THUNDERSTORM ACTIVITY OVER THE INTERIOR
AND THE NORTH/EASTERN SIDE OF THE ISLAND. FRIDAY/SATURDAY SEEMS TO
BE THE NEXT ACTIVE WEATHER DAY WITH DEEPER SHORT WAVE MOVING ALOFT
AND BETTER LOW LEVEL MOISTURE POOLING ACROSS THE AREA. ANOTHER
SHORT WAVE TROF MOVES ON MONDAY ENHANCING CONVECTION ONCE AGAIN.
DUE TO ALREADY SATURATED SOILS...ANY ADDITIONAL HEAVY RAINFALL WILL
LEAD TO URBAN AND SMALL STREAM/RIVER FLOODING. ALSO...LOCALIZED FLASH
FLOODING AND MUDSLIDES CANT BE RULED OUT EACH AFTERNOON.

&&

.AVIATION...MVFR CONDS WILL REMAIN POSSIBLE THROUGH AT LEAST 28/22Z
AT TJMZ/TJBQ AND POSSIBLY TJSJ TERMINALS IN SHRA/TSRA. MOUNTAIN
OBSCURATION ACROSS THE INTERIOR OF PR. MOSTLY VFR COND FOR THE REST
OF THE AREA. LOW LEVEL WINDS 5-15 KT FROM THE SE...BECOMING LIGHT
AND VARIABLE OVERNIGHT.


&&

.MARINE...LATEST BUOY READINGS INDICATE THAT THE NORTHERLY SWELL
IS SLOWLY FADING AND MODEL GUIDANCE SUGGEST THE SAME WITH
WAVE HEIGHTS AROUND 4 FEET AT 10 SECONDS. SEAS WILL REMAIN
GENERALLY BELOW 6 FEET ACROSS ALL LOCAL WATERS DURING THE NEXT
SEVERAL DAYS. UNSETTLED WEATHER CONDITIONS WILL CONTINUE ACROSS
THE REGIONAL WATERS INTO EARLY NEXT WEEK AS THUNDERSTORMS ARE
FORECAST TO DEVELOP OVER THE WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  88  75  88 /  40  50  40  40
STT  76  83  76  83 /  50  50  40  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

13/23





000
FXCA62 TJSJ 281416
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1016 AM AST THU APR 28 2016

.UPDATE...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO PREVAIL
ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING WEEKEND...
WITH DEEP CONVECTION AND PERIODS OF HEAVY RAIN EXPECTED DURING
THE AFTERNOON AND EVENING HOURS ACROSS NORTH...CENTRAL AND EASTERN
PUERTO RICO EACH DAY. DUE TO ALREADY SATURATED SOILS...HEAVY
RAINS WILL LEAD TO URBAN AND SMALL STREAM/RIVER FLOODING.

A BROAD TROUGH ACROSS THE WESTERN ATLANTIC TO THE NORTHERN CARIBBEAN
WILL CONTINUE TO MAINTAIN A DIVERGENT PATTERN ACROSS THE FORECAST
AREA DURING THE NEXT FEW DAYS...WITH UPPER LEVEL PERTURBATIONS
MOVING OVER THE ISLANDS FROM TIME TO TIME. THERE IS AN UPPER
LEVEL PERTURBATION REACHING THE FORECAST AREA SATURDAY...WITH
ANOTHER ONE REACHING THE FORECAST AREA LATER ON MONDAY. AT LOWER
LEVELS...A WARM/MOIST SOUTHEASTERLY WIND FLOW WILL CONTINUE TO
PREVAIL ACROSS THE FORECAST AREA WITH A SURFACE FRONTAL BOUNDARY
NORTH OF THE AREA SLOWLY DISSIPATING.

&&

.AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ/TJBQ/TISX AND TIST MAY EXPERIENCE TEMPO PERIOD OF MVFR/IFR CIGS
AND VIS BETWEEN 18Z-22Z. MOUNTAIN OBSCURATION ACROSS INTERIOR PR.
MOSTLY VFR COND FOR THE REST OF THE AREA. LOW LEVEL WINDS 5-15 KT
FROM THE SSE.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...FRONTAL BOUNDARY REMNANTS EXPECTED TO DISSIPATES ACROSS
THE ATLANTIC WATERS NORTH OF THE REGION. THIS MOISTURE IS
SUPPORTED BY A SURFACE TROUGH EXTENDING FROM HISPANIOLA ACROSS THE
ATLANTIC WATERS. A MID TO UPPER LEVEL TROUGH REMAINS NORTH OF THE
REGION. THESE FEATURES WILL MAINTAIN A MOIST AND UNSTABLE WEATHER
PATTERN ACROSS THE LOCAL ISLANDS AND SURROUNDING WATERS FOR THE
NEXT SEVERAL DAYS.

DISCUSSION...DOPPLER WEATHER RADAR OVERNIGHT AND EARLY THIS
MORNING DEPICTED SCATTERED TO NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS MOSTLY ACROSS THE ATLANTIC WATERS AS WELL AS ACROSS
THE SOUTHERN AND EASTERN SECTIONS OF PUERTO RICO. THIS ACTIVITY IS
THE RESULT OF ABUNDANT MOISTURE ASSOCIATED WITH A FRONTAL BOUNDARY
REMNANTS TO THE NORTH OF THE REGION AIDED BY A SURFACE TROUGH OVER
HISPANIOLA AND A MID TO UPPER LEVEL TROUGH JUST TO THE NORTH OF
THE REGION. THIS IS ALMOST THE SAME WEATHER PATTERN THAT PERSISTED
OVER THE FORECAST AREA FOR THE PAST DAYS.

TODAY AND FRIDAY WILL BE SIMILAR TO THE PREVIOUS DAYS. THE
COMBINATION OF THIS FEATURES WITH DAYTIME HEATING AND LOCAL
EFFECTS WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS
ALONG CORDILLERA CENTRAL LATE IN THE MORNING AND EARLY IN THE
AFTERNOON...MOVING BY MID AFTERNOON ACROSS OTHER PORTIONS OF THE
ISLANDS. THE GFS MODEL GUIDANCE SUGGESTS THAT THE AFTERNOON
CONVECTION WILL MOVE SLOWLY TOWARD THE NORTHWEST ACROSS THE
NORTHWEST QUADRANT OF PUERTO RICO. THE MID TO UPPER LEVEL WINDS
REMAIN FROM THE NORTHWEST AND THEREFORE SOME THUNDERSTORMS
ARE ALSO EXPECTED TO MOVE OVER EASTERN AND EASTERN INTERIOR
PUERTO RICO AS WELL AS OVER PARTS OF THE USVI. THEREFORE...A MOIST
AND UNSTABLE AIR MASS WILL CONTINUE TO PREVAIL ACROSS THE LOCAL
ISLANDS THROUGH AT LEAST THE UPCOMING WEEKEND. DUE TO ALREADY
SATURATED SOILS...HEAVY RAINS COULD LEAD TO URBAN AND SMALL STREAM
FLOODING.

IN THE LONG TERM...THE GFS MODEL GUIDANCE DEPICTED ABUNDANT DEEP
TROPICAL MOISTURE MOVING ACROSS THE LOCAL ISLANDS FROM SOUTH
AMERICA BY THE UPCOMING WEEK. STAY TUNED.

AVIATION...PREVAILING VFR CONDS THRU 28/14Z...WITH SFC WND CALM TO
LGT/VRB FOR PR TERMINALS. LGT WND MAINLY FM E AT TISX/TIST AND
TNCM/TKPK. SCT LYRS 018-025...SCT OCNL BKN 030...050 AND BKN-OVC LYR
100-120. SCT SHRA OVR ERN PR AND COASTAL WATERS BTW PR AND NRN
LEEWARDS. ISOLD TSRA OVR LOCAL WATERS MAX TOPS 350-400. BRIEF MTN
TOP OBSCR PSBL IN SHRA/LOW CLD CIG OVR ERN PR TIL 28/14Z. AFT 28/15Z
SHRA DVLPMNT LIKELY OVR NRN AND W PR AND WITH ISOLD TSRA AT TJBQ AFT
28/16Z. ADDITIONAL SHRA PSBL AT TJSJ...TJNR 28/18Z-23Z. WINDS WILL
CONT FM ESE EXCEPT WITH SEA BREEZE VARIATIONS DEVELOPING AFT 28/14Z
WITH WND 10-15KT OCNL HIR GUSTS.

MARINE...SEAS UP TO 6 FEET EXPECTED TODAY AND FRIDAY...DECREASING
SLIGHTLY FOR THE WEEKEND. THERE IS STILL A HIGH RISK OF RIP
CURRENTS FOR THE ATLANTIC COASTS OF PUERTO RICO AND CULEBRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  76  88  75 /  60  40  50  40
STT  84  76  83  76 /  50  50  50  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

13/23





000
FXCA62 TJSJ 281416
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1016 AM AST THU APR 28 2016

.UPDATE...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO PREVAIL
ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING WEEKEND...
WITH DEEP CONVECTION AND PERIODS OF HEAVY RAIN EXPECTED DURING
THE AFTERNOON AND EVENING HOURS ACROSS NORTH...CENTRAL AND EASTERN
PUERTO RICO EACH DAY. DUE TO ALREADY SATURATED SOILS...HEAVY
RAINS WILL LEAD TO URBAN AND SMALL STREAM/RIVER FLOODING.

A BROAD TROUGH ACROSS THE WESTERN ATLANTIC TO THE NORTHERN CARIBBEAN
WILL CONTINUE TO MAINTAIN A DIVERGENT PATTERN ACROSS THE FORECAST
AREA DURING THE NEXT FEW DAYS...WITH UPPER LEVEL PERTURBATIONS
MOVING OVER THE ISLANDS FROM TIME TO TIME. THERE IS AN UPPER
LEVEL PERTURBATION REACHING THE FORECAST AREA SATURDAY...WITH
ANOTHER ONE REACHING THE FORECAST AREA LATER ON MONDAY. AT LOWER
LEVELS...A WARM/MOIST SOUTHEASTERLY WIND FLOW WILL CONTINUE TO
PREVAIL ACROSS THE FORECAST AREA WITH A SURFACE FRONTAL BOUNDARY
NORTH OF THE AREA SLOWLY DISSIPATING.

&&

.AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ/TJBQ/TISX AND TIST MAY EXPERIENCE TEMPO PERIOD OF MVFR/IFR CIGS
AND VIS BETWEEN 18Z-22Z. MOUNTAIN OBSCURATION ACROSS INTERIOR PR.
MOSTLY VFR COND FOR THE REST OF THE AREA. LOW LEVEL WINDS 5-15 KT
FROM THE SSE.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...FRONTAL BOUNDARY REMNANTS EXPECTED TO DISSIPATES ACROSS
THE ATLANTIC WATERS NORTH OF THE REGION. THIS MOISTURE IS
SUPPORTED BY A SURFACE TROUGH EXTENDING FROM HISPANIOLA ACROSS THE
ATLANTIC WATERS. A MID TO UPPER LEVEL TROUGH REMAINS NORTH OF THE
REGION. THESE FEATURES WILL MAINTAIN A MOIST AND UNSTABLE WEATHER
PATTERN ACROSS THE LOCAL ISLANDS AND SURROUNDING WATERS FOR THE
NEXT SEVERAL DAYS.

DISCUSSION...DOPPLER WEATHER RADAR OVERNIGHT AND EARLY THIS
MORNING DEPICTED SCATTERED TO NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS MOSTLY ACROSS THE ATLANTIC WATERS AS WELL AS ACROSS
THE SOUTHERN AND EASTERN SECTIONS OF PUERTO RICO. THIS ACTIVITY IS
THE RESULT OF ABUNDANT MOISTURE ASSOCIATED WITH A FRONTAL BOUNDARY
REMNANTS TO THE NORTH OF THE REGION AIDED BY A SURFACE TROUGH OVER
HISPANIOLA AND A MID TO UPPER LEVEL TROUGH JUST TO THE NORTH OF
THE REGION. THIS IS ALMOST THE SAME WEATHER PATTERN THAT PERSISTED
OVER THE FORECAST AREA FOR THE PAST DAYS.

TODAY AND FRIDAY WILL BE SIMILAR TO THE PREVIOUS DAYS. THE
COMBINATION OF THIS FEATURES WITH DAYTIME HEATING AND LOCAL
EFFECTS WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS
ALONG CORDILLERA CENTRAL LATE IN THE MORNING AND EARLY IN THE
AFTERNOON...MOVING BY MID AFTERNOON ACROSS OTHER PORTIONS OF THE
ISLANDS. THE GFS MODEL GUIDANCE SUGGESTS THAT THE AFTERNOON
CONVECTION WILL MOVE SLOWLY TOWARD THE NORTHWEST ACROSS THE
NORTHWEST QUADRANT OF PUERTO RICO. THE MID TO UPPER LEVEL WINDS
REMAIN FROM THE NORTHWEST AND THEREFORE SOME THUNDERSTORMS
ARE ALSO EXPECTED TO MOVE OVER EASTERN AND EASTERN INTERIOR
PUERTO RICO AS WELL AS OVER PARTS OF THE USVI. THEREFORE...A MOIST
AND UNSTABLE AIR MASS WILL CONTINUE TO PREVAIL ACROSS THE LOCAL
ISLANDS THROUGH AT LEAST THE UPCOMING WEEKEND. DUE TO ALREADY
SATURATED SOILS...HEAVY RAINS COULD LEAD TO URBAN AND SMALL STREAM
FLOODING.

IN THE LONG TERM...THE GFS MODEL GUIDANCE DEPICTED ABUNDANT DEEP
TROPICAL MOISTURE MOVING ACROSS THE LOCAL ISLANDS FROM SOUTH
AMERICA BY THE UPCOMING WEEK. STAY TUNED.

AVIATION...PREVAILING VFR CONDS THRU 28/14Z...WITH SFC WND CALM TO
LGT/VRB FOR PR TERMINALS. LGT WND MAINLY FM E AT TISX/TIST AND
TNCM/TKPK. SCT LYRS 018-025...SCT OCNL BKN 030...050 AND BKN-OVC LYR
100-120. SCT SHRA OVR ERN PR AND COASTAL WATERS BTW PR AND NRN
LEEWARDS. ISOLD TSRA OVR LOCAL WATERS MAX TOPS 350-400. BRIEF MTN
TOP OBSCR PSBL IN SHRA/LOW CLD CIG OVR ERN PR TIL 28/14Z. AFT 28/15Z
SHRA DVLPMNT LIKELY OVR NRN AND W PR AND WITH ISOLD TSRA AT TJBQ AFT
28/16Z. ADDITIONAL SHRA PSBL AT TJSJ...TJNR 28/18Z-23Z. WINDS WILL
CONT FM ESE EXCEPT WITH SEA BREEZE VARIATIONS DEVELOPING AFT 28/14Z
WITH WND 10-15KT OCNL HIR GUSTS.

MARINE...SEAS UP TO 6 FEET EXPECTED TODAY AND FRIDAY...DECREASING
SLIGHTLY FOR THE WEEKEND. THERE IS STILL A HIGH RISK OF RIP
CURRENTS FOR THE ATLANTIC COASTS OF PUERTO RICO AND CULEBRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  76  88  75 /  60  40  50  40
STT  84  76  83  76 /  50  50  50  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

13/23





000
FXCA62 TJSJ 280750
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
350 AM AST THU APR 28 2016

.SYNOPSIS...FRONTAL BOUNDARY REMNANTS EXPECTED TO DISSIPATES ACROSS
THE ATLANTIC WATERS NORTH OF THE REGION. THIS MOISTURE IS
SUPPORTED BY A SURFACE TROUGH EXTENDING FROM HISPANIOLA ACROSS THE
ATLANTIC WATERS. A MID TO UPPER LEVEL TROUGH REMAINS NORTH OF THE
REGION. THESE FEATURES WILL MAINTAIN A MOIST AND UNSTABLE WEATHER
PATTERN ACROSS THE LOCAL ISLANDS AND SURROUNDING WATERS FOR THE
NEXT SEVERAL DAYS.

&&

.DISCUSSION...DOPPLER WEATHER RADAR OVERNIGHT AND EARLY THIS
MORNING DEPICTED SCATTERED TO NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS MOSTLY ACROSS THE ATLANTIC WATERS AS WELL AS ACROSS
THE SOUTHERN AND EASTERN SECTIONS OF PUERTO RICO. THIS ACTIVITY IS
THE RESULT OF ABUNDANT MOISTURE ASSOCIATED WITH A FRONTAL BOUNDARY
REMNANTS TO THE NORTH OF THE REGION AIDED BY A SURFACE TROUGH OVER
HISPANIOLA AND A MID TO UPPER LEVEL TROUGH JUST TO THE NORTH OF
THE REGION. THIS IS ALMOST THE SAME WEATHER PATTERN THAT PERSISTED
OVER THE FORECAST AREA FOR THE PAST DAYS.

TODAY AND FRIDAY WILL BE SIMILAR TO THE PREVIOUS DAYS. THE
COMBINATION OF THIS FEATURES WITH DAYTIME HEATING AND LOCAL
EFFECTS WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS
ALONG CORDILLERA CENTRAL LATE IN THE MORNING AND EARLY IN THE
AFTERNOON...MOVING BY MID AFTERNOON ACROSS OTHER PORTIONS OF THE
ISLANDS. THE GFS MODEL GUIDANCE SUGGESTS THAT THE AFTERNOON
CONVECTION WILL MOVE SLOWLY TOWARD THE NORTHWEST ACROSS THE
NORTHWEST QUADRANT OF PUERTO RICO. THE MID TO UPPER LEVEL WINDS
REMAIN FROM THE NORTHWEST AND THEREFORE SOME THUNDERSTORMS
ARE ALSO EXPECTED TO MOVE OVER EASTERN AND EASTERN INTERIOR
PUERTO RICO AS WELL AS OVER PARTS OF THE USVI. THEREFORE...A MOIST
AND UNSTABLE AIR MASS WILL CONTINUE TO PREVAIL ACROSS THE LOCAL
ISLANDS THROUGH AT LEAST THE UPCOMING WEEKEND. DUE TO ALREADY
SATURATED SOILS...HEAVY RAINS COULD LEAD TO URBAN AND SMALL STREAM
FLOODING.

IN THE LONG TERM...THE GFS MODEL GUIDANCE DEPICTED ABUNDANT DEEP
TROPICAL MOISTURE MOVING ACROSS THE LOCAL ISLANDS FROM SOUTH
AMERICA BY THE UPCOMING WEEK. STAY TUNED.

&&

.AVIATION...PREVAILING VFR CONDS THRU 28/14Z...WITH SFC WND CALM TO
LGT/VRB FOR PR TERMINALS. LGT WND MAINLY FM E AT TISX/TIST AND
TNCM/TKPK. SCT LYRS 018-025...SCT OCNL BKN 030...050 AND BKN-OVC LYR
100-120. SCT SHRA OVR ERN PR AND COASTAL WATERS BTW PR AND NRN
LEEWARDS. ISOLD TSRA OVR LOCAL WATERS MAX TOPS 350-400. BRIEF MTN
TOP OBSCR PSBL IN SHRA/LOW CLD CIG OVR ERN PR TIL 28/14Z. AFT 28/15Z
SHRA DVLPMNT LIKELY OVR NRN AND W PR AND WITH ISOLD TSRA AT TJBQ AFT
28/16Z. ADDITIONAL SHRA PSBL AT TJSJ...TJNR 28/18Z-23Z. WINDS WILL
CONT FM ESE EXCEPT WITH SEA BREEZE VARIATIONS DEVELOPING AFT 28/14Z
WITH WND 10-15KT OCNL HIR GUSTS.

&&

.MARINE...SEAS UP TO 6 FEET EXPECTED TODAY AND FRIDAY...DECREASING
SLIGHTLY FOR THE WEEKEND. THERE IS STILL A HIGH RISK OF RIP
CURRENTS FOR THE ATLANTIC COASTS OF PUERTO RICO AND CULEBRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  76  88  75 /  60  40  50  40
STT  84  76  83  76 /  50  50  50  40

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK THROUGH THIS AFTERNOON FOR CULEBRA-NORTH
     CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-SOUTHEAST-
     WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

09/72





000
FXCA62 TJSJ 280147
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
947 PM AST WED APR 27 2016

.UPDATE...NUMEROUS SHOWERS AND A FEW THUNDERSTORMS CAUSED SOME
URBAN AND FLASH FLOODING THIS AFTERNOON ACROSS NW PR AND EASTERN
PR. THE HEAVIEST RAINFALL WAS OBSERVED ACROSS THE LUQUILLO
MOUNTAIN RANGE WHERE FLASH FLOODING WAS OBSERVED. THIS WAS DUE TO
THE COMBINATION OF THE AVAILABLE MOISTURE AND INSTABILITY IN THE
AREA. ALSO...SINCE THE SOILS ARE COMPLETELY SATURATED BY NOW...THE
RAIN TURNS INTO RUNOFF RATHER QUICKLY AND THE RIVERS RISE VERY
RAPIDLY.

IT LOOKS LIKE THURSDAY AND FRIDAY WILL BE SIMILAR BECAUSE THE
MOIST AND UNSTABLE AIRMASS WILL CONTINUE OVER THE LOCAL AREA.
HOWEVER...THERE IS SOME DISAGREEMENT BETWEEN THE MODELS. THE NMM
MODEL TENDS TO FAVOR AFTERNOON CONVECTION ACROSS NW-PR WHILE THE
GFS AND WRF MODELS ARE MUCH MORE GENERALIZED WITH THE WRF BEING
VERY BULLISH ON THE RAINFALL AMOUNTS ON THURSDAY AFTERNOON.
HAVING SAID THAT...I QUESTION HOW WELL ANY OF THE MODELS ARE
ACTUALLY DOING SINCE NONE OF THEM HAVE REALLY CAPTURED WHAT HAS
HAPPENED THE PAST COUPLE OF DAYS. SO THERE IS QUITE A BIT OF
UNCERTAINTY IN THE FORECAST FOR TOMORROW THURSDAY BUT GIVEN THE
FACT THAT THE BIG PICTURE PATTERN HAS NOT REALLY CHANGED
MUCH...THERE IS REALLY NO REASON TO THINK THAT WE WILL OBSERVE
ANYTHING OTHER THAN ACTIVE WEATHER ONCE AGAIN.

&&


.AVIATION...VFR CONDS EXPECTED OVERNIGHT WITH WINDS LIGHT AND
VARIABLE FOR THE TERMINALS IN PR WHILE THE USVI AND TNCM/TKPK CAN
OBSERVE LIGHT EASTERLY WINDS. VCTS LIKELY TOMORROW IN THE
AFTERNOON WITH TEMPO TSRA LIKELY AT TJBQ AFTER 28/16Z AND POSSIBLE
AT TJSJ AFTER 28/18Z. WINDS EXPECTED TO BE EASTERLY WITH SEA
BREEZE VARIATIONS DEVELOPING AFTER 28/14Z WITH A SPEED AROUND
10-15KT.


&&

.MARINE...SEAS UP TO 6 FEET EXPECTED TONIGHT AND
THURSDAY...DECREASING SLIGHTLY FOR THE WEEKEND. THERE IS STILL A
HIGH RISK OF RIP CURRENTS FOR THE ATLANTIC COASTS OF PUERTO RICO
AND CULEBRA.


&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING
WEEKEND.

DISCUSSION...A HIGH PRESSURE ACROSS THE WESTERN ATLANTIC WILL
MOVE EAST NORTHEAST INTO THE CENTRAL ATLANTIC AS AN INVERTED
TROUGH SPREADS OVER THE CENTRAL CARIBBEAN AND HISPANIOLA. THIS
PATTERN WILL PROMOTE A WARM/MOIST SOUTHEASTERLY WIND FLOW ACROSS
THE FORECAST AREA. SURFACE FRONTAL BOUNDARY NORTH OF THE AREA...
WILL CONTINUE TO SLOWLY DISSIPATE.

AT UPPER LEVELS...A BROAD TROUGH ACROSS THE WESTERN ATLANTIC TO
THE NORTHERN CARIBBEAN WILL CONTINUE TO MAINTAIN A DIVERGENT
PATTERN ACROSS THE FORECAST AREA DURING THE NEXT FEW DAYS...WITH
UPPER LEVEL PERTURBATIONS MOVING OVER THE ISLANDS FROM TIME TO
TIME. THERE IS IN FACT A SHORT WAVE TROUGH NOW MOVING OVER THE
AREA...WITH THE NEXT UPPER LEVEL PERTURBATION REACHING THE
FORECAST AREA FRIDAY EVENING. A THIRD PERTURBATION WILL THEN
REACH THE FORECAST AREA LATER ON SATURDAY.

THEREFORE...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING
WEEKEND...WITH DEEP CONVECTION AND PERIODS OF HEAVY RAIN EXPECTED
DURING THE AFTERNOON HOURS ACROSS PORTIONS OF THE CORDILLERA AS
WELL AS NORTHERN SLOPES EACH DAY. DUE TO ALREADY SATURATED
SOILS...HEAVY RAINS COULD LEAD TO URBAN AND SMALL STREAM FLOODING.

AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ AND TJBQ MAY EXPERIENCE TEMPO PERIOD OF MVFR CIGS AND VIS
BETWEEN 18Z-22Z. MOUNTAIN OBSCURATION ACROSS INTERIOR PR. MOSTLY
VFR COND FOR THE REST OF THE AREA. LOW LEVEL WINDS 5-15 KT FROM
THE SSE FROM SFC TO FL050.

MARINE...A COMBINATION OF NORTHERLY SWELL AND EASTERLY WIND WAVES
WILL BUILD THE SEAS UP TO 6 FEET THROUGH THIS EVENING...INCREASING
THE RISK OF RIP CURRENTS FROM MODERATE TO HIGH THROUGHOUT THE DAY.
THEREFORE...RIP CURRENT STATEMENT HAS BEEN ISSUED UNTIL THURSDAY
MORNING...FOR THE POSSIBILITY OF STRONG RIP CURRENTS ALONG THE
NORTH COAST BEACHES OF PUERTO RICO AND CULEBRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  87  76  87 /  30  60  40  50
STT  76  86  76  83 /  50  50  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK THROUGH THURSDAY AFTERNOON FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

13/25





000
FXCA62 TJSJ 280147
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
947 PM AST WED APR 27 2016

.UPDATE...NUMEROUS SHOWERS AND A FEW THUNDERSTORMS CAUSED SOME
URBAN AND FLASH FLOODING THIS AFTERNOON ACROSS NW PR AND EASTERN
PR. THE HEAVIEST RAINFALL WAS OBSERVED ACROSS THE LUQUILLO
MOUNTAIN RANGE WHERE FLASH FLOODING WAS OBSERVED. THIS WAS DUE TO
THE COMBINATION OF THE AVAILABLE MOISTURE AND INSTABILITY IN THE
AREA. ALSO...SINCE THE SOILS ARE COMPLETELY SATURATED BY NOW...THE
RAIN TURNS INTO RUNOFF RATHER QUICKLY AND THE RIVERS RISE VERY
RAPIDLY.

IT LOOKS LIKE THURSDAY AND FRIDAY WILL BE SIMILAR BECAUSE THE
MOIST AND UNSTABLE AIRMASS WILL CONTINUE OVER THE LOCAL AREA.
HOWEVER...THERE IS SOME DISAGREEMENT BETWEEN THE MODELS. THE NMM
MODEL TENDS TO FAVOR AFTERNOON CONVECTION ACROSS NW-PR WHILE THE
GFS AND WRF MODELS ARE MUCH MORE GENERALIZED WITH THE WRF BEING
VERY BULLISH ON THE RAINFALL AMOUNTS ON THURSDAY AFTERNOON.
HAVING SAID THAT...I QUESTION HOW WELL ANY OF THE MODELS ARE
ACTUALLY DOING SINCE NONE OF THEM HAVE REALLY CAPTURED WHAT HAS
HAPPENED THE PAST COUPLE OF DAYS. SO THERE IS QUITE A BIT OF
UNCERTAINTY IN THE FORECAST FOR TOMORROW THURSDAY BUT GIVEN THE
FACT THAT THE BIG PICTURE PATTERN HAS NOT REALLY CHANGED
MUCH...THERE IS REALLY NO REASON TO THINK THAT WE WILL OBSERVE
ANYTHING OTHER THAN ACTIVE WEATHER ONCE AGAIN.

&&


.AVIATION...VFR CONDS EXPECTED OVERNIGHT WITH WINDS LIGHT AND
VARIABLE FOR THE TERMINALS IN PR WHILE THE USVI AND TNCM/TKPK CAN
OBSERVE LIGHT EASTERLY WINDS. VCTS LIKELY TOMORROW IN THE
AFTERNOON WITH TEMPO TSRA LIKELY AT TJBQ AFTER 28/16Z AND POSSIBLE
AT TJSJ AFTER 28/18Z. WINDS EXPECTED TO BE EASTERLY WITH SEA
BREEZE VARIATIONS DEVELOPING AFTER 28/14Z WITH A SPEED AROUND
10-15KT.


&&

.MARINE...SEAS UP TO 6 FEET EXPECTED TONIGHT AND
THURSDAY...DECREASING SLIGHTLY FOR THE WEEKEND. THERE IS STILL A
HIGH RISK OF RIP CURRENTS FOR THE ATLANTIC COASTS OF PUERTO RICO
AND CULEBRA.


&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING
WEEKEND.

DISCUSSION...A HIGH PRESSURE ACROSS THE WESTERN ATLANTIC WILL
MOVE EAST NORTHEAST INTO THE CENTRAL ATLANTIC AS AN INVERTED
TROUGH SPREADS OVER THE CENTRAL CARIBBEAN AND HISPANIOLA. THIS
PATTERN WILL PROMOTE A WARM/MOIST SOUTHEASTERLY WIND FLOW ACROSS
THE FORECAST AREA. SURFACE FRONTAL BOUNDARY NORTH OF THE AREA...
WILL CONTINUE TO SLOWLY DISSIPATE.

AT UPPER LEVELS...A BROAD TROUGH ACROSS THE WESTERN ATLANTIC TO
THE NORTHERN CARIBBEAN WILL CONTINUE TO MAINTAIN A DIVERGENT
PATTERN ACROSS THE FORECAST AREA DURING THE NEXT FEW DAYS...WITH
UPPER LEVEL PERTURBATIONS MOVING OVER THE ISLANDS FROM TIME TO
TIME. THERE IS IN FACT A SHORT WAVE TROUGH NOW MOVING OVER THE
AREA...WITH THE NEXT UPPER LEVEL PERTURBATION REACHING THE
FORECAST AREA FRIDAY EVENING. A THIRD PERTURBATION WILL THEN
REACH THE FORECAST AREA LATER ON SATURDAY.

THEREFORE...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING
WEEKEND...WITH DEEP CONVECTION AND PERIODS OF HEAVY RAIN EXPECTED
DURING THE AFTERNOON HOURS ACROSS PORTIONS OF THE CORDILLERA AS
WELL AS NORTHERN SLOPES EACH DAY. DUE TO ALREADY SATURATED
SOILS...HEAVY RAINS COULD LEAD TO URBAN AND SMALL STREAM FLOODING.

AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ AND TJBQ MAY EXPERIENCE TEMPO PERIOD OF MVFR CIGS AND VIS
BETWEEN 18Z-22Z. MOUNTAIN OBSCURATION ACROSS INTERIOR PR. MOSTLY
VFR COND FOR THE REST OF THE AREA. LOW LEVEL WINDS 5-15 KT FROM
THE SSE FROM SFC TO FL050.

MARINE...A COMBINATION OF NORTHERLY SWELL AND EASTERLY WIND WAVES
WILL BUILD THE SEAS UP TO 6 FEET THROUGH THIS EVENING...INCREASING
THE RISK OF RIP CURRENTS FROM MODERATE TO HIGH THROUGHOUT THE DAY.
THEREFORE...RIP CURRENT STATEMENT HAS BEEN ISSUED UNTIL THURSDAY
MORNING...FOR THE POSSIBILITY OF STRONG RIP CURRENTS ALONG THE
NORTH COAST BEACHES OF PUERTO RICO AND CULEBRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  87  76  87 /  30  60  40  50
STT  76  86  76  83 /  50  50  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK THROUGH THURSDAY AFTERNOON FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

13/25





000
FXCA62 TJSJ 271731
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
131 PM AST WED APR 27 2016

.SYNOPSIS...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING
WEEKEND.

&&

.DISCUSSION...A HIGH PRESSURE ACROSS THE WESTERN ATLANTIC WILL
MOVE EAST NORTHEAST INTO THE CENTRAL ATLANTIC AS AN INVERTED
TROUGH SPREADS OVER THE CENTRAL CARIBBEAN AND HISPANIOLA. THIS
PATTERN WILL PROMOTE A WARM/MOIST SOUTHEASTERLY WIND FLOW ACROSS
THE FORECAST AREA. SURFACE FRONTAL BOUNDARY NORTH OF THE AREA...
WILL CONTINUE TO SLOWLY DISSIPATE.

AT UPPER LEVELS...A BROAD TROUGH ACROSS THE WESTERN ATLANTIC TO
THE NORTHERN CARIBBEAN WILL CONTINUE TO MAINTAIN A DIVERGENT
PATTERN ACROSS THE FORECAST AREA DURING THE NEXT FEW DAYS...WITH
UPPER LEVEL PERTURBATIONS MOVING OVER THE ISLANDS FROM TIME TO
TIME. THERE IS IN FACT A SHORT WAVE TROUGH NOW MOVING OVER THE
AREA...WITH THE NEXT UPPER LEVEL PERTURBATION REACHING THE
FORECAST AREA FRIDAY EVENING. A THIRD PERTURBATION WILL THEN
REACH THE FORECAST AREA LATER ON SATURDAY.

THEREFORE...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL ISLANDS THROUGH AT LEAST THE UPCOMING
WEEKEND...WITH DEEP CONVECTION AND PERIODS OF HEAVY RAIN EXPECTED
DURING THE AFTERNOON HOURS ACROSS PORTIONS OF THE CORDILLERA AS
WELL AS NORTHERN SLOPES EACH DAY. DUE TO ALREADY SATURATED
SOILS...HEAVY RAINS COULD LEAD TO URBAN AND SMALL STREAM FLOODING.

&&

.AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ AND TJBQ MAY EXPERIENCE TEMPO PERIOD OF MVFR CIGS AND VIS
BETWEEN 18Z-22Z. MOUNTAIN OBSCURATION ACROSS INTERIOR PR. MOSTLY
VFR COND FOR THE REST OF THE AREA. LOW LEVEL WINDS 5-15 KT FROM
THE SSE FROM SFC TO FL050.

&&

.MARINE...A COMBINATION OF NORTHERLY SWELL AND EASTERLY WIND WAVES
WILL BUILD THE SEAS UP TO 6 FEET THROUGH THIS EVENING...INCREASING
THE RISK OF RIP CURRENTS FROM MODERATE TO HIGH THROUGHOUT THE DAY.
THEREFORE...RIP CURRENT STATEMENT HAS BEEN ISSUED UNTIL THURSDAY
MORNING...FOR THE POSSIBILITY OF STRONG RIP CURRENTS ALONG THE
NORTH COAST BEACHES OF PUERTO RICO AND CULEBRA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  86  76  87 /  30  60  40  50
STT  76  86  76  83 /  50  50  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK THROUGH LATE TONIGHT FOR CULEBRA-NORTH
     CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-SOUTHEAST-
     WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

11/23/82





000
FXCA62 TJSJ 271418
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1018 AM AST WED APR 27 2016

.UPDATE...MOISTURE AND INSTABILITY REMAIN HIGH ACROSS THE LOCAL
AREA TODAY. AS A RESULT...EXPECT ANOTHER ROUND OF ACTIVE WEATHER
DURING THE AFTERNOON HOURS ALONG THE CORDILLERA CENTRAL AND THE
NORTHERN HALF OF PUERTO RICO. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP ACROSS THE INTERIOR PORTIONS OF PR BY EARLY
IN THE AFTERNOON AND DRIFT TO THE NORTH AND NORTHEAST PORTIONS OF
PR AS MID-UPPER LEVEL WINDS PREVAIL FROM THE SOUTHWEST. WE INCREASE
THE POP ACROSS THE NORTHERN HALF OF PR THIS AFTERNOON AS WELL AS
THE CHANCES OF THUNDERSTORMS.

&&

.AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ MAY EXPERIENCE TEMPO PERIOD OF MVFR CIGS AND VIS BETWEEN 17Z-
22Z. LOW LEVEL WINDS ARE LIGHT FROM THE SSE FROM SFC TO FL050.
STRONGER SW WINDS OF 20-40 KT PREVAIL FM FL050 TO FL300.

&&

.MARINE...A COMBINATION OF NORTHERLY SWELL AND EASTERLY WIND WAVES
WILL BUILD THE SEAS UP TO 6 FEET THROUGH THIS EVENING...INCREASING
THE RISK OF RIP CURRENTS FROM MODERATE TO HIGH THROUGHOUT THE DAY.
THEREFORE...RIP CURRENT STATEMENT HAS BEEN ISSUED UNTIL THIS EVENING...
FOR THE POSSIBILITY OF STRONG RIP CURRENTS ALONG THE NORTH COAST
BEACHES OF PUERTO RICO AND CULEBRA.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...FRONTAL BOUNDARY REMNANTS EXPECTED TO CONTINUE ACROSS
THE REGION TODAY. A MID TO UPPER LEVEL TROUGH NORTH OF THE REGION
AND ASSOCIATED DIVERGENT PATTERN IN COMBINATION WITH A SURFACE
TROUGH OVER HISPANIOLA WILL MAINTAIN AN UNSTABLE WEATHER PATTERN
ACROSS THE FORECAST AREA FOR THE NEXT SEVERAL DAYS.

DISCUSSION...DOPPLER WEATHER RADAR THIS MORNING DEPICTED SHOWERS
AND THUNDERSTORMS ACROSS THE ATLANTIC COASTAL WATERS. HOWEVER...
LIMITED SHOWER ACTIVITY WAS OBSERVED OVER LAND AREAS SO FAR THIS
MORNING. A SURFACE TROUGH OVER HISPANIOLA WILL MAINTAIN THE
FRONTAL BOUNDARY REMNANTS ACROSS THE REGION TODAY. THIS FEATURE
WILL CONTINUE TO CREATE ABUNDANT CLOUDINESS AND MOISTURE ACROSS
THE LOCAL ISLANDS ANS SURROUNDING WATERS TODAY. A WEAK MID TO
UPPER LEVEL TROUGH NORTH OF THE REGION WILL AID TO CREATE AN
UNSTABLE ENVIRONMENT FOR THE NEXT FEW DAYS.

VARIABLE CLOUDY SKIES WITH SHOWERS AND THUNDERSTORMS WILL
CONTINUE ACROSS THE SURROUNDING WATERS THIS MORNING. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP EARLY IN THE AFTERNOON ALONG
CORDILLERA CENTRAL. UNDER THE CURRENT UNSTABLE WEATHER PATTERN AND
THE AVAILABLE MOISTURE...ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS PUERTO RICO THIS AFTERNOON. THE
SOILS ARE ALREADY SATURATED DUE TO THE PREVIOUS RAINFALL EVENTS.
AS A RESULT MODERATE TO HEAVY RAIN COULD LEAD TO URBAN FLOODING...
FLASH FLOODS AND MUDSLIDES. IN THE LONG TERM...IT LOOKS LIKE THAT
SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS THE FORECAST
AREA FOR THE REST OF THE WEEK. ENOUGH MOISTURE AND INSTABILITY IS
EXPECTED TO BE PRESENT THURSDAY AND FRIDAY AND POSSIBLE BEYOND.

AVIATION...FRONTAL BOUNDARY SAGGED ACROSS ATLANTIC WATERS JUST
N OF LOCAL ISLANDS ... WITH SCT-BKN CLD LYRS FL020...FL060 AND BKN-
OVC FL100-FL150. EMBEDDED SHRA N OR PR AND NRN VIRGIN ISLANDS OVR
ATL WATERS N OF LOCAL ISLANDS WITH ISOLD TSRA TOPS 350-380. MTN TOP
OBSCR DUE TO LOW CLDS AND SHRA ERN PR TIL 27/14Z. MSTLY CLDY CONDS
FCST THRU 27/14Z WITH PREVAILING VFR AT TAF SITES TIL 27/16Z. AFT
27/16Z INCR CLD COVERAGE OVR INTERIOR SECTION OF PR WITH DVLPMNT OF
SHRA/ISOLD TSRA VCTY TJBQ... TJMZ....TJSJ...TNCM AND TKPK. ISOLD
SHRA VCNTY TISX AND TIST DURG PRD. SFC WINDS FM SE 5 TO 10KT. WINDS
ABV FL060 UP TO FL200 WSW 15-25 KT BCMG FM W 30-40 KT ABV FL200. MAX
WIND 60-70KTS NR FL 450.

MARINE...SEAS WILL INCREASE GRADUALLY UP TO 6 FEET THIS MORNING AS
A NORTHERLY SWELL MOVES INTO THE LOCAL AREA. THE RIP CURRENT RISK
IS EXPECTED TO BE HIGH TODAY ACROSS THE NORTH COAST OF PUERTO RICO.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  86  76  88  76 /  70  30  40  40
STT  84  76  84  76 /  70  30  40  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

23/11





000
FXCA62 TJSJ 271418
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1018 AM AST WED APR 27 2016

.UPDATE...MOISTURE AND INSTABILITY REMAIN HIGH ACROSS THE LOCAL
AREA TODAY. AS A RESULT...EXPECT ANOTHER ROUND OF ACTIVE WEATHER
DURING THE AFTERNOON HOURS ALONG THE CORDILLERA CENTRAL AND THE
NORTHERN HALF OF PUERTO RICO. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP ACROSS THE INTERIOR PORTIONS OF PR BY EARLY
IN THE AFTERNOON AND DRIFT TO THE NORTH AND NORTHEAST PORTIONS OF
PR AS MID-UPPER LEVEL WINDS PREVAIL FROM THE SOUTHWEST. WE INCREASE
THE POP ACROSS THE NORTHERN HALF OF PR THIS AFTERNOON AS WELL AS
THE CHANCES OF THUNDERSTORMS.

&&

.AVIATION...MVFR/IFR CONDS WILL BE LIKELY NEAR TSRA THIS AFTERNOON.
TJSJ MAY EXPERIENCE TEMPO PERIOD OF MVFR CIGS AND VIS BETWEEN 17Z-
22Z. LOW LEVEL WINDS ARE LIGHT FROM THE SSE FROM SFC TO FL050.
STRONGER SW WINDS OF 20-40 KT PREVAIL FM FL050 TO FL300.

&&

.MARINE...A COMBINATION OF NORTHERLY SWELL AND EASTERLY WIND WAVES
WILL BUILD THE SEAS UP TO 6 FEET THROUGH THIS EVENING...INCREASING
THE RISK OF RIP CURRENTS FROM MODERATE TO HIGH THROUGHOUT THE DAY.
THEREFORE...RIP CURRENT STATEMENT HAS BEEN ISSUED UNTIL THIS EVENING...
FOR THE POSSIBILITY OF STRONG RIP CURRENTS ALONG THE NORTH COAST
BEACHES OF PUERTO RICO AND CULEBRA.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...FRONTAL BOUNDARY REMNANTS EXPECTED TO CONTINUE ACROSS
THE REGION TODAY. A MID TO UPPER LEVEL TROUGH NORTH OF THE REGION
AND ASSOCIATED DIVERGENT PATTERN IN COMBINATION WITH A SURFACE
TROUGH OVER HISPANIOLA WILL MAINTAIN AN UNSTABLE WEATHER PATTERN
ACROSS THE FORECAST AREA FOR THE NEXT SEVERAL DAYS.

DISCUSSION...DOPPLER WEATHER RADAR THIS MORNING DEPICTED SHOWERS
AND THUNDERSTORMS ACROSS THE ATLANTIC COASTAL WATERS. HOWEVER...
LIMITED SHOWER ACTIVITY WAS OBSERVED OVER LAND AREAS SO FAR THIS
MORNING. A SURFACE TROUGH OVER HISPANIOLA WILL MAINTAIN THE
FRONTAL BOUNDARY REMNANTS ACROSS THE REGION TODAY. THIS FEATURE
WILL CONTINUE TO CREATE ABUNDANT CLOUDINESS AND MOISTURE ACROSS
THE LOCAL ISLANDS ANS SURROUNDING WATERS TODAY. A WEAK MID TO
UPPER LEVEL TROUGH NORTH OF THE REGION WILL AID TO CREATE AN
UNSTABLE ENVIRONMENT FOR THE NEXT FEW DAYS.

VARIABLE CLOUDY SKIES WITH SHOWERS AND THUNDERSTORMS WILL
CONTINUE ACROSS THE SURROUNDING WATERS THIS MORNING. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP EARLY IN THE AFTERNOON ALONG
CORDILLERA CENTRAL. UNDER THE CURRENT UNSTABLE WEATHER PATTERN AND
THE AVAILABLE MOISTURE...ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS PUERTO RICO THIS AFTERNOON. THE
SOILS ARE ALREADY SATURATED DUE TO THE PREVIOUS RAINFALL EVENTS.
AS A RESULT MODERATE TO HEAVY RAIN COULD LEAD TO URBAN FLOODING...
FLASH FLOODS AND MUDSLIDES. IN THE LONG TERM...IT LOOKS LIKE THAT
SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS THE FORECAST
AREA FOR THE REST OF THE WEEK. ENOUGH MOISTURE AND INSTABILITY IS
EXPECTED TO BE PRESENT THURSDAY AND FRIDAY AND POSSIBLE BEYOND.

AVIATION...FRONTAL BOUNDARY SAGGED ACROSS ATLANTIC WATERS JUST
N OF LOCAL ISLANDS ... WITH SCT-BKN CLD LYRS FL020...FL060 AND BKN-
OVC FL100-FL150. EMBEDDED SHRA N OR PR AND NRN VIRGIN ISLANDS OVR
ATL WATERS N OF LOCAL ISLANDS WITH ISOLD TSRA TOPS 350-380. MTN TOP
OBSCR DUE TO LOW CLDS AND SHRA ERN PR TIL 27/14Z. MSTLY CLDY CONDS
FCST THRU 27/14Z WITH PREVAILING VFR AT TAF SITES TIL 27/16Z. AFT
27/16Z INCR CLD COVERAGE OVR INTERIOR SECTION OF PR WITH DVLPMNT OF
SHRA/ISOLD TSRA VCTY TJBQ... TJMZ....TJSJ...TNCM AND TKPK. ISOLD
SHRA VCNTY TISX AND TIST DURG PRD. SFC WINDS FM SE 5 TO 10KT. WINDS
ABV FL060 UP TO FL200 WSW 15-25 KT BCMG FM W 30-40 KT ABV FL200. MAX
WIND 60-70KTS NR FL 450.

MARINE...SEAS WILL INCREASE GRADUALLY UP TO 6 FEET THIS MORNING AS
A NORTHERLY SWELL MOVES INTO THE LOCAL AREA. THE RIP CURRENT RISK
IS EXPECTED TO BE HIGH TODAY ACROSS THE NORTH COAST OF PUERTO RICO.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  86  76  88  76 /  70  30  40  40
STT  84  76  84  76 /  70  30  40  20

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK UNTIL 6 PM AST THIS EVENING FOR CULEBRA-
     NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-
     SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

23/11





000
FXCA62 TJSJ 270736
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
336 AM AST WED APR 27 2016

.SYNOPSIS...FRONTAL BOUNDARY REMNANTS EXPECTED TO CONTINUE ACROSS
THE REGION TODAY. A MID TO UPPER LEVEL TROUGH NORTH OF THE REGION
AND ASSOCIATED DIVERGENT PATTERN IN COMBINATION WITH A SURFACE
TROUGH OVER HISPANIOLA WILL MAINTAIN AN UNSTABLE WEATHER PATTERN
ACROSS THE FORECAST AREA FOR THE NEXT SEVERAL DAYS.

&&

.DISCUSSION...DOPPLER WEATHER RADAR THIS MORNING DEPICTED SHOWERS
AND THUNDERSTORMS ACROSS THE ATLANTIC COASTAL WATERS. HOWEVER...
LIMITED SHOWER ACTIVITY WAS OBSERVED OVER LAND AREAS SO FAR THIS
MORNING. A SURFACE TROUGH OVER HISPANIOLA WILL MAINTAIN THE
FRONTAL BOUNDARY REMNANTS ACROSS THE REGION TODAY. THIS FEATURE
WILL CONTINUE TO CREATE ABUNDANT CLOUDINESS AND MOISTURE ACROSS
THE LOCAL ISLANDS ANS SURROUNDING WATERS TODAY. A WEAK MID TO
UPPER LEVEL TROUGH NORTH OF THE REGION WILL AID TO CREATE AN
UNSTABLE ENVIRONMENT FOR THE NEXT FEW DAYS.

VARIABLE CLOUDY SKIES WITH SHOWERS AND THUNDERSTORMS WILL
CONTINUE ACROSS THE SURROUNDING WATERS THIS MORNING. SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP EARLY IN THE AFTERNOON ALONG
CORDILLERA CENTRAL. UNDER THE CURRENT UNSTABLE WEATHER PATTERN AND
THE AVAILABLE MOISTURE...ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS PUERTO RICO THIS AFTERNOON. THE
SOILS ARE ALREADY SATURATED DUE TO THE PREVIOUS RAINFALL EVENTS.
AS A RESULT MODERATE TO HEAVY RAIN COULD LEAD TO URBAN FLOODING...
FLASH FLOODS AND MUDSLIDES. IN THE LONG TERM...IT LOOKS LIKE THAT
SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS THE FORECAST
AREA FOR THE REST OF THE WEEK. ENOUGH MOISTURE AND INSTABILITY IS
EXPECTED TO BE PRESENT THURSDAY AND FRIDAY AND POSSIBLE BEYOND.

&&

.AVIATION...FRONTAL BOUNDARY SAGGED ACROSS ATLANTIC WATERS JUST
N OF LOCAL ISLANDS ... WITH SCT-BKN CLD LYRS FL020...FL060 AND BKN-
OVC FL100-FL150. EMBEDDED SHRA N OR PR AND NRN VIRGIN ISLANDS OVR
ATL WATERS N OF LOCAL ISLANDS WITH ISOLD TSRA TOPS 350-380. MTN TOP
OBSCR DUE TO LOW CLDS AND SHRA ERN PR TIL 27/14Z. MSTLY CLDY CONDS
FCST THRU 27/14Z WITH PREVAILING VFR AT TAF SITES TIL 27/16Z. AFT
27/16Z INCR CLD COVERAGE OVR INTERIOR SECTION OF PR WITH DVLPMNT OF
SHRA/ISOLD TSRA VCTY TJBQ... TJMZ....TJSJ...TNCM AND TKPK. ISOLD
SHRA VCNTY TISX AND TIST DURG PRD. SFC WINDS FM SE 5 TO 10KT. WINDS
ABV FL060 UP TO FL200 WSW 15-25 KT BCMG FM W 30-40 KT ABV FL200. MAX
WIND 60-70KTS NR FL 450.

&&

.MARINE...SEAS WILL INCREASE GRADUALLY UP TO 6 FEET THIS MORNING AS
A NORTHERLY SWELL MOVES INTO THE LOCAL AREA. THE RIP CURRENT RISK
IS EXPECTED TO BE HIGH TODAY ACROSS THE NORTH COAST OF PUERTO RICO.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  86  76  88  76 /  40  30  40  40
STT 84 76 84 76 / 30 30 40 20 &&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH RIP CURRENT RISK FROM 6 AM AST THIS MORNING THROUGH THIS
     AFTERNOON FOR CULEBRA-NORTH CENTRAL-NORTHEAST-NORTHWEST-SAN
     JUAN AND VICINITY-SOUTHEAST-WESTERN INTERIOR.

VI...NONE.
AM...NONE.
&&

$$

09/72





000
FXCA62 TJSJ 270147
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
947 PM AST TUE APR 26 2016

.UPDATE...THE AFTERNOON SHOWER ACTIVITY WAS MAINLY ACROSS THE
NORTHERN HALF OF PUERTO RICO WITH THE NORTHWESTERN SECTIONS
RECEIVING THE MOST RAIN...SLIGHTLY OVER 2 INCHES IN SOME AREAS
ACCORDING TO RADAR ESTIMATES. THUNDERSTORMS WERE ALSO
DETECTED...SOME OF THE PRODUCING FREQUENT LIGHTNING OVER LAND AND
OVER THE WATERS. EVEN THOUGH THE SHOWER ACTIVITY WAS NOT AS BAD AS
IT WAS YESTERDAY...THERE WERE SEVERAL AREAS WITH SIGNIFICANT URBAN
FLOODING. SINCE THE SOILS ARE ALREADY SATURATED...IT WILL NOT
TAKE MUCH RAIN TO CAUSE URBAN AND SMALL STREAM FLOODING.

THE LATEST GUIDANCE SUGGESTS THAT SHOWERS SHOULD BE LIGHT
OVERNIGHT AND INTO THE MORNING HOURS...MOSTLY OVER THE WATERS AND
USVI. THEN...AFTERNOON CONVECTION MAY ONCE AGAIN
OCCUR...PARTICULARLY ACROSS THE NORTH CENTRAL AND NORTHWESTERN
PORTIONS OF PR. THIS IS NOT TO SAY THAT RAIN IS NOT POSSIBLE
ELSEWHERE...IT IS...BUT THOSE SECTORS IN THE NORTH CENTRAL AND
NORTHWESTERN PR APPEAR TO HAVE THE HIGHEST CHANCE OF THUNDERSTORMS
AND SIGNIFICANT RAINFALL ON WEDNESDAY AFTERNOON.

IN THE LONG TERM...IT LOOKS LIKE THE REST OF THE WEEK WILL BE
RAINY. ENOUGH MOISTURE AND INSTABILITY IS EXPECTED TO BE PRESENT
FOR THE REST OF THE WEEK. THURSDAY AND FRIDAY LOOK A BIT MORE
UNSTABLE THAN THE REST OF THE DAYS THROUGH SUNDAY. THE LONG RANGE
MODELS LIKE MORE RAIN FOR THOSE DAYS OVER THE LOCAL AREA.

&&

.AVIATION...A MASS OF RAIN AND CLOUDS COVERS THE FORECAST AREA NORTH
OF PR AND THE USVI. TOPS OF THE RADAR ECHOS ARE SOLID BELOW FL220
AND SOME AREAS RANGE FROM FL260-320 WITH ISOLD TOPS TO FL470 WITH
TSRA. CONDS EXPECTED TO CONTINUE THRU 27/12Z. ALL BUT TJBQ AND TJSJ
WILL REMAIN VFR THRU 27/15Z. TJBQ WILL SEE SOME IFR AND TJSJ MAY SEE
BRIEF MVFR IN -SHRA. AFT 27/12Z MOISTURE MOVES INTO TNCM AND TKPK
FOR PERIODS OF MVFR AND -RA THEN AFT 27/15Z TSRA TO RETURN TO PR
INTERIOR TILL ARND 27/22Z. SFC WINDS SE 5 TO 12 KT.

&&

.MARINE...SEAS WILL BE GENERALLY UP TO 4 FEET
OVERNIGHT...INCREASING GRADUALLY UP TO 6 FEET BY WEDNESDAY
AFTERNOON AS A NORTHERLY SWELL MOVES INTO THE LOCAL AREA. THE RIP
CURRENT RISK IS EXPECTED TO BE HIGH ON WEDNESDAY ACROSS THE NORTH
COAST OF PUERTO RICO.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...A BROAD MID TO UPPER LEVEL TROUGH WILL PROVIDE ENOUGH
INSTABILITY TODAY AND TOMORROW. AT LOW LEVEL...A SET OF LOW LEVEL
TROUGH WILL BE SUPPORTED BY A A FRONTAL BOUNDARY TO THE NORTH OF
THE ISLANDS AND PLENTY OF TROPICAL MOISTURE. ANOTHER SHORT WAVE IS
EXPECTED FOR WEDNESDAY. NOW...TO THE WEST OF MAINLAND PUERTO
RICO...A CONVERGENCE ZONE WAS OBSERVED OVER THE EAST OF THE
DOMINICAN REPUBLIC. ALTHOUGH...A MID TO UPPER LEVEL TROUGHINESS
IS EXPECTED TO EXIT THE REGION BY WEDNESDAY...A FADING FRONTAL
BOUNDARY WILL SUPPORT TROPICAL MOISTURE TO POOL OVER THE REGION
THROUGH THE WEEK. IN ADDITION...THE REGION IS EXPECTED TO CONTINUE
UNDER THE INFLUENCE OF A NEGATIVE PHASE OF THE MADDEN- JULIAN
OSCILLATION...MJO.

DISCUSSION...A LAYER OF MID TO UPPER LEVEL CLOUDS CREATED MOSTLY
CLOUDY CONDITIONS ACROSS MOST OF THE LOCAL ISLANDS DURING THE
MORNING HOURS. THE DOPPLER RADAR DETECTED SHOWERS MAINLY OVER THE
CARIBBEAN AND ATLANTIC WATERS EARLY IN THE MORNING...THEN
THUNDERSTORMS FORMED OVER THE OFFSHORE ATLANTIC WATERS LATE IN THE
MORNING INTO THE AFTERNOON. ALSO SHOWERS MOVED ACROSS THE EASTERN
HALF OF PUERTO RICO THIS MORNING...FOLLOWED BY AFTERNOON
CONVECTION ACROSS THE SOUTH AND WEST PORTIONS OF PUERTO RICO. SOME
MODERATE TO HEAVY SHOWERS MOVED ACROSS THE METROPOLITAN AREA OF
SAN JUAN EARLY THIS AFTERNOON. UNDER THE CURRENT UNSTABLE WEATHER
PATTERN AND THE AVAILABLE MOISTURE CONTINUE TO EXPECT ANOTHER
ROUND OF SHOWERS AND THUNDERSTORMS ACROSS PUERTO RICO AND THE
SURROUNDING WATERS OF THE U.S. VIRGIN ISLANDS. THE SOILS ARE
ALREADY SATURATED DUE TO THE PREVIOUS RAINFALL EVENTS. AS A RESULT
MODERATE TO HEAVY RAIN COULD LEAD TO URBAN FLOODING...FLASH
FLOODS AND MUDSLIDES.

MODEL GUIDANCE CONTINUES TO SUGGEST AN UNSTABLE PATTERN OVER THE
REGION. IN ADDITION...THE GFS IS SUGGESTING THE ISLANDS UNDER THE
INFLUENCE OF A NEGATIVE PHASE OF THE MADDEN-JULIAN OSCILLATION...
MJO...WHICH IS FAVORABLE FOR AN UNSTABLE ATMOSPHERE OVER THE
REGION. THIS FACTOR WILL COMBINE WITH PLENTY OF TROPICAL MOISTURE
TO PRODUCE ROUNDS OF SHOWERS AND THUNDERSTORMS MAINLY EACH
AFTERNOON ACROSS THE REGION.

AVIATION...SHRA/TSRA DEVELOPMENT AND MOUNTAIN OBSCURATION
EXPECTED ACROSS PUERTO RICO THROUGH 26/22Z. THIS MAY RESULT IN
PERIODS OF MVFR CONDS AT JSJ/JPS/JBQ LATER THIS AFTERNOON.
ELSEWHERE...MAINLY VFR WITH PASSING SHOWERS. WINDS WILL CONTINUE
TO BE LIGHT AND VARIABLE.

MARINE...THE SEAS AND WINDS ARE EXPECTED BELOW THE PRECAUTIONARY
STATEMENTS DURING THE NEXT FEW DAYS. MARINERS CAN EXPECT SEAS
BELOW 5 FEET AND WINDS BELOW 18 KNOTS. HOWEVER LOCALLY HIGHER SEAS
AND WINDS MAY BE POSSIBLE IN AND NEAR SHOWERS AND THUNDERSTORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  86  76  87 /  20  40  30  40
STT  78  84  76  84 /  20  30  30  40

&&

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

$$

12/25





000
FXCA62 TJSJ 270147
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
947 PM AST TUE APR 26 2016

.UPDATE...THE AFTERNOON SHOWER ACTIVITY WAS MAINLY ACROSS THE
NORTHERN HALF OF PUERTO RICO WITH THE NORTHWESTERN SECTIONS
RECEIVING THE MOST RAIN...SLIGHTLY OVER 2 INCHES IN SOME AREAS
ACCORDING TO RADAR ESTIMATES. THUNDERSTORMS WERE ALSO
DETECTED...SOME OF THE PRODUCING FREQUENT LIGHTNING OVER LAND AND
OVER THE WATERS. EVEN THOUGH THE SHOWER ACTIVITY WAS NOT AS BAD AS
IT WAS YESTERDAY...THERE WERE SEVERAL AREAS WITH SIGNIFICANT URBAN
FLOODING. SINCE THE SOILS ARE ALREADY SATURATED...IT WILL NOT
TAKE MUCH RAIN TO CAUSE URBAN AND SMALL STREAM FLOODING.

THE LATEST GUIDANCE SUGGESTS THAT SHOWERS SHOULD BE LIGHT
OVERNIGHT AND INTO THE MORNING HOURS...MOSTLY OVER THE WATERS AND
USVI. THEN...AFTERNOON CONVECTION MAY ONCE AGAIN
OCCUR...PARTICULARLY ACROSS THE NORTH CENTRAL AND NORTHWESTERN
PORTIONS OF PR. THIS IS NOT TO SAY THAT RAIN IS NOT POSSIBLE
ELSEWHERE...IT IS...BUT THOSE SECTORS IN THE NORTH CENTRAL AND
NORTHWESTERN PR APPEAR TO HAVE THE HIGHEST CHANCE OF THUNDERSTORMS
AND SIGNIFICANT RAINFALL ON WEDNESDAY AFTERNOON.

IN THE LONG TERM...IT LOOKS LIKE THE REST OF THE WEEK WILL BE
RAINY. ENOUGH MOISTURE AND INSTABILITY IS EXPECTED TO BE PRESENT
FOR THE REST OF THE WEEK. THURSDAY AND FRIDAY LOOK A BIT MORE
UNSTABLE THAN THE REST OF THE DAYS THROUGH SUNDAY. THE LONG RANGE
MODELS LIKE MORE RAIN FOR THOSE DAYS OVER THE LOCAL AREA.

&&

.AVIATION...A MASS OF RAIN AND CLOUDS COVERS THE FORECAST AREA NORTH
OF PR AND THE USVI. TOPS OF THE RADAR ECHOS ARE SOLID BELOW FL220
AND SOME AREAS RANGE FROM FL260-320 WITH ISOLD TOPS TO FL470 WITH
TSRA. CONDS EXPECTED TO CONTINUE THRU 27/12Z. ALL BUT TJBQ AND TJSJ
WILL REMAIN VFR THRU 27/15Z. TJBQ WILL SEE SOME IFR AND TJSJ MAY SEE
BRIEF MVFR IN -SHRA. AFT 27/12Z MOISTURE MOVES INTO TNCM AND TKPK
FOR PERIODS OF MVFR AND -RA THEN AFT 27/15Z TSRA TO RETURN TO PR
INTERIOR TILL ARND 27/22Z. SFC WINDS SE 5 TO 12 KT.

&&

.MARINE...SEAS WILL BE GENERALLY UP TO 4 FEET
OVERNIGHT...INCREASING GRADUALLY UP TO 6 FEET BY WEDNESDAY
AFTERNOON AS A NORTHERLY SWELL MOVES INTO THE LOCAL AREA. THE RIP
CURRENT RISK IS EXPECTED TO BE HIGH ON WEDNESDAY ACROSS THE NORTH
COAST OF PUERTO RICO.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS...A BROAD MID TO UPPER LEVEL TROUGH WILL PROVIDE ENOUGH
INSTABILITY TODAY AND TOMORROW. AT LOW LEVEL...A SET OF LOW LEVEL
TROUGH WILL BE SUPPORTED BY A A FRONTAL BOUNDARY TO THE NORTH OF
THE ISLANDS AND PLENTY OF TROPICAL MOISTURE. ANOTHER SHORT WAVE IS
EXPECTED FOR WEDNESDAY. NOW...TO THE WEST OF MAINLAND PUERTO
RICO...A CONVERGENCE ZONE WAS OBSERVED OVER THE EAST OF THE
DOMINICAN REPUBLIC. ALTHOUGH...A MID TO UPPER LEVEL TROUGHINESS
IS EXPECTED TO EXIT THE REGION BY WEDNESDAY...A FADING FRONTAL
BOUNDARY WILL SUPPORT TROPICAL MOISTURE TO POOL OVER THE REGION
THROUGH THE WEEK. IN ADDITION...THE REGION IS EXPECTED TO CONTINUE
UNDER THE INFLUENCE OF A NEGATIVE PHASE OF THE MADDEN- JULIAN
OSCILLATION...MJO.

DISCUSSION...A LAYER OF MID TO UPPER LEVEL CLOUDS CREATED MOSTLY
CLOUDY CONDITIONS ACROSS MOST OF THE LOCAL ISLANDS DURING THE
MORNING HOURS. THE DOPPLER RADAR DETECTED SHOWERS MAINLY OVER THE
CARIBBEAN AND ATLANTIC WATERS EARLY IN THE MORNING...THEN
THUNDERSTORMS FORMED OVER THE OFFSHORE ATLANTIC WATERS LATE IN THE
MORNING INTO THE AFTERNOON. ALSO SHOWERS MOVED ACROSS THE EASTERN
HALF OF PUERTO RICO THIS MORNING...FOLLOWED BY AFTERNOON
CONVECTION ACROSS THE SOUTH AND WEST PORTIONS OF PUERTO RICO. SOME
MODERATE TO HEAVY SHOWERS MOVED ACROSS THE METROPOLITAN AREA OF
SAN JUAN EARLY THIS AFTERNOON. UNDER THE CURRENT UNSTABLE WEATHER
PATTERN AND THE AVAILABLE MOISTURE CONTINUE TO EXPECT ANOTHER
ROUND OF SHOWERS AND THUNDERSTORMS ACROSS PUERTO RICO AND THE
SURROUNDING WATERS OF THE U.S. VIRGIN ISLANDS. THE SOILS ARE
ALREADY SATURATED DUE TO THE PREVIOUS RAINFALL EVENTS. AS A RESULT
MODERATE TO HEAVY RAIN COULD LEAD TO URBAN FLOODING...FLASH
FLOODS AND MUDSLIDES.

MODEL GUIDANCE CONTINUES TO SUGGEST AN UNSTABLE PATTERN OVER THE
REGION. IN ADDITION...THE GFS IS SUGGESTING THE ISLANDS UNDER THE
INFLUENCE OF A NEGATIVE PHASE OF THE MADDEN-JULIAN OSCILLATION...
MJO...WHICH IS FAVORABLE FOR AN UNSTABLE ATMOSPHERE OVER THE
REGION. THIS FACTOR WILL COMBINE WITH PLENTY OF TROPICAL MOISTURE
TO PRODUCE ROUNDS OF SHOWERS AND THUNDERSTORMS MAINLY EACH
AFTERNOON ACROSS THE REGION.

AVIATION...SHRA/TSRA DEVELOPMENT AND MOUNTAIN OBSCURATION
EXPECTED ACROSS PUERTO RICO THROUGH 26/22Z. THIS MAY RESULT IN
PERIODS OF MVFR CONDS AT JSJ/JPS/JBQ LATER THIS AFTERNOON.
ELSEWHERE...MAINLY VFR WITH PASSING SHOWERS. WINDS WILL CONTINUE
TO BE LIGHT AND VARIABLE.

MARINE...THE SEAS AND WINDS ARE EXPECTED BELOW THE PRECAUTIONARY
STATEMENTS DURING THE NEXT FEW DAYS. MARINERS CAN EXPECT SEAS
BELOW 5 FEET AND WINDS BELOW 18 KNOTS. HOWEVER LOCALLY HIGHER SEAS
AND WINDS MAY BE POSSIBLE IN AND NEAR SHOWERS AND THUNDERSTORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  86  76  87 /  20  40  30  40
STT  78  84  76  84 /  20  30  30  40

&&

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

$$

12/25





000
FXCA62 TJSJ 261808
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
208 PM AST TUE APR 26 2016

.SYNOPSIS...A BROAD MID TO UPPER LEVEL TROUGH WILL PROVIDE ENOUGH
INSTABILITY TODAY AND TOMORROW. AT LOW LEVEL...A SET OF LOW LEVEL
TROUGH WILL BE SUPPORTED BY A A FRONTAL BOUNDARY TO THE NORTH OF
THE ISLANDS AND PLENTY OF TROPICAL MOISTURE. ANOTHER SHORT WAVE IS
EXPECTED FOR WEDNESDAY. NOW...TO THE WEST OF MAINLAND PUERTO
RICO...A CONVERGENCE ZONE WAS OBSERVED OVER THE EAST OF THE
DOMINICAN REPUBLIC. ALTHOUGH...A MID TO UPPER LEVEL TROUGHINESS
IS EXPECTED TO EXIT THE REGION BY WEDNESDAY...A FADING FRONTAL
BOUNDARY WILL SUPPORT TROPICAL MOISTURE TO POOL OVER THE REGION
THROUGH THE WEEK. IN ADDITION...THE REGION IS EXPECTED TO CONTINUE
UNDER THE INFLUENCE OF A NEGATIVE PHASE OF THE MADDEN- JULIAN
OSCILLATION...MJO.

&&

.DISCUSSION...A LAYER OF MID TO UPPER LEVEL CLOUDS CREATED MOSTLY
CLOUDY CONDITIONS ACROSS MOST OF THE LOCAL ISLANDS DURING THE
MORNING HOURS. THE DOPPLER RADAR DETECTED SHOWERS MAINLY OVER THE
CARIBBEAN AND ATLANTIC WATERS EARLY IN THE MORNING...THEN
THUNDERSTORMS FORMED OVER THE OFFSHORE ATLANTIC WATERS LATE IN THE
MORNING INTO THE AFTERNOON. ALSO SHOWERS MOVED ACROSS THE EASTERN
HALF OF PUERTO RICO THIS MORNING...FOLLOWED BY AFTERNOON
CONVECTION ACROSS THE SOUTH AND WEST PORTIONS OF PUERTO RICO. SOME
MODERATE TO HEAVY SHOWERS MOVED ACROSS THE METROPOLITAN AREA OF
SAN JUAN EARLY THIS AFTERNOON. UNDER THE CURRENT UNSTABLE WEATHER
PATTERN AND THE AVAILABLE MOISTURE CONTINUE TO EXPECT ANOTHER
ROUND OF SHOWERS AND THUNDERSTORMS ACROSS PUERTO RICO AND THE
SURROUNDING WATERS OF THE U.S. VIRGIN ISLANDS. THE SOILS ARE
ALREADY SATURATED DUE TO THE PREVIOUS RAINFALL EVENTS. AS A RESULT
MODERATE TO HEAVY RAIN COULD LEAD TO URBAN FLOODING...FLASH
FLOODS AND MUDSLIDES.

MODEL GUIDANCE CONTINUES TO SUGGEST AN UNSTABLE PATTERN OVER THE
REGION. IN ADDITION...THE GFS IS SUGGESTING THE ISLANDS UNDER THE
INFLUENCE OF A NEGATIVE PHASE OF THE MADDEN-JULIAN OSCILLATION...
MJO...WHICH IS FAVORABLE FOR AN UNSTABLE ATMOSPHERE OVER THE
REGION. THIS FACTOR WILL COMBINE WITH PLENTY OF TROPICAL MOISTURE
TO PRODUCE ROUNDS OF SHOWERS AND THUNDERSTORMS MAINLY EACH
AFTERNOON ACROSS THE REGION.

&&

.AVIATION...SHRA/TSRA DEVELOPMENT AND MOUNTAIN OBSCURATION
EXPECTED ACROSS PUERTO RICO THROUGH 26/22Z. THIS MAY RESULT IN
PERIODS OF MVFR CONDS AT JSJ/JPS/JBQ LATER THIS AFTERNOON.
ELSEWHERE...MAINLY VFR WITH PASSING SHOWERS. WINDS WILL CONTINUE
TO BE LIGHT AND VARIABLE.

&&

.MARINE...THE SEAS AND WINDS ARE EXPECTED BELOW THE PRECAUTIONARY
STATEMENTS DURING THE NEXT FEW DAYS. MARINERS CAN EXPECT SEAS
BELOW 5 FEET AND WINDS BELOW 18 KNOTS. HOWEVER LOCALLY HIGHER SEAS
AND WINDS MAY BE POSSIBLE IN AND NEAR SHOWERS AND THUNDERSTORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  76  88  76  89 /  20  40  30  40
STT  78  85  77  84 /  20  30  30  40

&&

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

$$

23/27





000
FXCA62 TJSJ 261502
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1102 AM AST TUE APR 26 2016

.UPDATED...FORECAST ON TRACK. UNDER UPPER LEVEL TROUGH AND
ASSOCIATED DIVERGENT PATTERN...MID LEVEL SHORT WAVE PERTURBATIONS
MOVING ACROSS THE AREA FROM TIME TO TIME AND PLENTY OF LOW
LEVEL MOISTURE...CONTINUE TO EXPECT A MOIST AND UNSTABLE AIR
MASS ACROSS THE LOCAL ISLANDS TO RESULT IN CLOUDINESS...SHOWERS
AND THUNDERSTORMS ACROSS THE CENTRAL AND NORTH PUERTO RICO EACH
AFTERNOON. DUE TO ALREADY SATURATED SOILS...HEAVY RAINS COULD
LEAD TO URBAN AND SMALL STREAM FLOODING.

&&

.AVIATION...SHRA/TSRA DEVELOPMENT AND MOUNTAIN OBSCURATION
EXPECTED ACROSS PUERTO RICO THROUGH 26/22Z. THIS MAY RESULT IN
PERIODS OF MVFR CONDS AT JSJ/JPS/JBQ LATER THIS AFTERNOON.
ELSEWHERE...MAINLY VFR WITH PASSING SHOWERS. WINDS WILL CONTINUE
TO BE LIGHT AND VARIABLE.

&&

.MARINE...TRANQUIL MARINE CONDITIONS EXPECTED DURING THE NEXT
FEW DAYS...HOWEVER LOCALLY HIGHER SEAS AND WINDS MAY BE POSSIBLE
IN THUNDERSTORMS.

&&

.PREV DISCUSSION... /ISSUED /

SYNOPSIS....
BROAD MID TO UPPER LEVEL TROUGH WILL CONTINUE TO DOMINATE THE
FLOW ACROSS THE WESTERN ATLANTIC AND LOCAL REGION THROUGH MOST OF
THE WEEK. THIS WILL BE SUPPORTED BY INDUCED LOW LEVEL TROUGHINESS
AND MOISTURE CONVERGENCE ACROSS THE NORTHEASTERN CARIBBEAN THROUGH
THE REST OF THE WORK WEEK AND INTO THE UPCOMING WEEKEND. A SHORT
WAVE MOVED ACROSS THE REGION DURING THE PAST 24 HOURS BUT WILL BE
QUICKLY FOLLOWED BY YET ANOTHER LATER TONIGHT AND EARLY WEDNESDAY
MORNING. THIS WILL HELP MAINTAIN UPPER LEVEL INSTABILITY ACROSS
THE REGION. MOISTURE ALONG A SLOWLY DISSIPATING FRONTAL BOUNDARY
WILL CONTINUE TO POOL ACROSS THE REGION DURING MOST OF THE WEEK.
THIS WILL SUPPORT PERIODS OF NOCTURNAL AND DAYTIME CONVECTION
ACROSS THE ISLANDS AND COASTAL WATERS.

DISCUSSION...SURFACE TROUGH COMBINED WITH POOLING OF DEEP MOISTURE
ACROSS THE REGION WILL MAINTAIN MOIST AND VERY UNSTABLE ENVIRONMENT
THROUGH MUCH OF THE WEEK. SOIL ACROSS THE ISLANDS REMAIN VERY SATURATED
ESPECIALLY ACROSS PUERTO RICO. THEREFORE ANY ADDITIONAL RAINFALL
WILL WORSEN THE SITUATION AND LEAD TO FLOODING OF URBAN AREAS ESPECIALLY
IN AREAS OF POOR DRAINAGE ALONG WITH MINOR FLOODING OF RIVERS AND
STREAMS. IN ADDITION...RECENT RAINS FROM PREVIOUS DAYS HAVE LEFT
AREAS OF STEEP TERRAIN VERY UNSTABLE. ANY ADDITIONAL RAINFALL EVEN
OF LIGHT TO MODERATE INTENSITY WILL LEAD TO MUDSLIDES AND ROCKFALL
DUE TO THE LOOSE SOIL. THE COMBINATION OF LOW LEVEL SOUTHERLY FLOW
ALONG WITH THE MOISTURE CONVERGENCE AND INSTABILITY WILL FAVOR LATE
MORNING AND AFTERNOON CONVECTION ACROSS THE INTERIOR AND NORTHERN
PORTIONS OF PUERTO RICO. RECENT MODEL GUIDANCE CONTINUE TO SUPPORT
A MOIST ENVIRONMENT AND POTENTIAL FOR GOOD RAINS AND CONVECTIVE
DEVELOPMENT ACROSS PUERTO RICO TODAY.

ALTHOUGH AVAILABLE MOISTURE AND PWAT VALUES ARE TO SLOWLY DECREASE
DURING THE LATTER PART OF THE WEEK...EXPECT THE LOCAL AIRMASS TO
REMAIN VERY UNSETTLED WITH ENHANCED CONVECTIVE DEVELOPMENT LIKELY
TO PERSIST EACH DAY.

AVIATION...MOSTLY VFR CONDITIONS EXPECTED THIS MORNING ACROSS THE
LOCAL FLYING AREA. -SHRA POSSIBLE AT TJSJ AND TIST AS MOISTURE
APPROACHES SLOWLY TO THE TERMINALS. WINDS WILL BE LIGHT AND VARIABLE
UNTIL 26/14Z...INCREASING SLIGHTLY AFTER THAT AND BECOMING MORE
EASTERLY WITH SEA BREEZE VARIATIONS...BUT MAY BE LIGHT AND VARIABLE
AT TIMES. CIGS AT AROUND FL070 ARE EXPECTED THROUGH THE FORECAST
PERIOD. SHRA/TSRA DEVELOPING ACROSS CENTRAL PR AFTER 26/16Z...COULD
CAUSE VCTS ACROSS THE TERMINALS IN PR.

MARINE...RECENT DATA FROM THE SURROUNDING BUOYS SUGGEST SEAS AND
SWELL ACTION HAVE SUBSIDED. WINDS WILL HOWEVER GRADUALLY INCREASE
DURING THE NEXT 48 HOURS AND SEAS WILL FOLLOW. THEREFORE SMALL
CRAFT ADVISORIES MAY BE REQUIRED FOR AT LEAST THE EASTERN QUADRANT
OF THE OFFSHORE ATLANTIC WATERS BY WEDNESDAY NIGHT. ELSEWHERE MODELS
SUGGEST SEAS TO REMAIN 6 FEET OR LESS DURING THE NEXT 7 DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  87  76  88  76 /  70  20  40  30
STT  85  78  85  77 /  20  20  30  30

&&

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

$$

23/11





000
FXCA62 TJSJ 260821
AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
421 AM AST TUE APR 26 2016

.SYNOPSIS....
BROAD MID TO UPPER LEVEL TROUGH WILL CONTINUE TO DOMINATE THE
FLOW ACROSS THE WESTERN ATLANTIC AND LOCAL REGION THROUGH MOST OF
THE WEEK. THIS WILL BE SUPPORTED BY INDUCED LOW LEVEL TROUGHINESS
AND MOISTURE CONVERGENCE ACROSS THE NORTHEASTERN CARIBBEAN THROUGH
THE REST OF THE WORK WEEK AND INTO THE UPCOMING WEEKEND. A SHORT
WAVE MOVED ACROSS THE REGION DURING THE PAST 24 HOURS BUT WILL BE
QUICKLY FOLLOWED BY YET ANOTHER LATER TONIGHT AND EARLY WEDNESDAY
MORNING. THIS WILL HELP MAINTAIN UPPER LEVEL INSTABILITY ACROSS
THE REGION. MOISTURE ALONG A SLOWLY DISSIPATING FRONTAL BOUNDARY
WILL CONTINUE TO POOL ACROSS THE REGION DURING MOST OF THE WEEK.
THIS WILL SUPPORT PERIODS OF NOCTURNAL AND DAYTIME CONVECTION
ACROSS THE ISLANDS AND COASTAL WATERS.

&&

.DISCUSSION...SURFACE TROUGH COMBINED WITH POOLING OF DEEP MOISTURE
ACROSS THE REGION WILL MAINTAIN MOIST AND VERY UNSTABLE ENVIRONMENT
THROUGH MUCH OF THE WEEK. SOIL ACROSS THE ISLANDS REMAIN VERY SATURATED
ESPECIALLY ACROSS PUERTO RICO. THEREFORE ANY ADDITIONAL RAINFALL
WILL WORSEN THE SITUATION AND LEAD TO FLOODING OF URBAN AREAS ESPECIALLY
IN AREAS OF POOR DRAINAGE ALONG WITH MINOR FLOODING OF RIVERS AND
STREAMS. IN ADDITION...RECENT RAINS FROM PREVIOUS DAYS HAVE LEFT
AREAS OF STEEP TERRAIN VERY UNSTABLE. ANY ADDITIONAL RAINFALL EVEN
OF LIGHT TO MODERATE INTENSITY WILL LEAD TO MUDSLIDES AND ROCKFALL
DUE TO THE LOOSE SOIL. THE COMBINATION OF LOW LEVEL SOUTHERLY FLOW
ALONG WITH THE MOISTURE CONVERGENCE AND INSTABILITY WILL FAVOR LATE
MORNING AND AFTERNOON CONVECTION ACROSS THE INTERIOR AND NORTHERN
PORTIONS OF PUERTO RICO. RECENT MODEL GUIDANCE CONTINUE TO SUPPORT
A MOIST ENVIRONMENT AND POTENTIAL FOR GOOD RAINS AND CONVECTIVE
DEVELOPMENT ACROSS PUERTO RICO TODAY.

ALTHOUGH AVAILABLE MOISTURE AND PWAT VALUES ARE TO SLOWLY DECREASE
DURING THE LATTER PART OF THE WEEK...EXPECT THE LOCAL AIRMASS TO
REMAIN VERY UNSETTLED WITH ENHANCED CONVECTIVE DEVELOPMENT LIKELY
TO PERSIST EACH DAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THIS MORNING ACROSS THE
LOCAL FLYING AREA. -SHRA POSSIBLE AT TJSJ AND TIST AS MOISTURE
APPROACHES SLOWLY TO THE TERMINALS. WINDS WILL BE LIGHT AND VARIABLE
UNTIL 26/14Z...INCREASING SLIGHTLY AFTER THAT AND BECOMING MORE
EASTERLY WITH SEA BREEZE VARIATIONS...BUT MAY BE LIGHT AND VARIABLE
AT TIMES. CIGS AT AROUND FL070 ARE EXPECTED THROUGH THE FORECAST
PERIOD. SHRA/TSRA DEVELOPING ACROSS CENTRAL PR AFTER 26/16Z...COULD
CAUSE VCTS ACROSS THE TERMINALS IN PR.

&&

.MARINE...RECENT DATA FROM THE SURROUNDING BUOYS SUGGEST SEAS AND
SWELL ACTION HAVE SUBSIDED. WINDS WILL HOWEVER GRADUALLY INCREASE
DURING THE NEXT 48 HOURS AND SEAS WILL FOLLOW. THEREFORE SMALL
CRAFT ADVISORIES MAY BE REQUIRED FOR AT LEAST THE EASTERN QUADRANT
OF THE OFFSHORE ATLANTIC WATERS BY WEDNESDAY NIGHT. ELSEWHERE MODELS
SUGGEST SEAS TO REMAIN 6 FEET OR LESS DURING THE NEXT 7 DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  85  76  87  76 /  30  60  70  20
STT  87  78  85  78 /  20  20  20  20

&&

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

$$

72/09





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