Caribbean - Central America Weather

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
446 AM AST FRI JAN 9 2015

.SYNOPSIS...STRENGTHENING ATLC RIDGE WILL LEAD TO A GRADUAL INCREASE
IN WINDS AND TRADE WIND SHOWERS TODAY THROUGH MON MORNING. RIDGE
THEN WEAKENS THROUGH THE END OF NEXT WEEK AS LOW PRES FORMS OFF
THE EAST COAST.

&&

.DISCUSSION...LATEST TPW IMAGERY SHOWS PRETTY DECENT MOISTURE TO
THE EAST OF THE LEEWARD ISLANDS AND THIS WILL ADVECT RAPIDLY WWD LATER
THIS MORNING ACROSS PR/USVI AS ATLC RIDGE STRENGTHENS AND WINDS
INCREASE. SO EXPECT EXTENSIVE CLOUD COVER TODAY WITH SHOWERS
LIKELY ESPECIALLY FROM ARECIBO EAST TO FAJARDO. A SHARP DECLINE IN
MOISTURE IS SUGGESTED FOR TONIGHT BY ALL GUIDANCE AND HAVE
FOLLOWED THIS CLOSELY.

AS ARCTIC HIGH PRES EXITS THE MID ATLC COAST SAT NIGHT AND BUILDS
ACROSS THE ATLC...LOCAL PRES GRADIENT WILL TIGHTEN SIGNIFICANTLY
WITH WINDS STRENGTHENING FURTHER SUNDAY INTO MONDAY WITH CLOUD
CLUSTERS AND TRADE WIND SHOWERS ADVECTING OVR THE LOCAL AREA
DURING THE WEEKEND INTO EARLY NEXT WEEK.

ATLC RIDGE THEN BEGINS TO WEAKEN MONDAY AFTERNOON THROUGH THE END
OF NEXT WEEK WITH TRADE WINDS AND ASSOCIATED SHOWER ACTIVITY
DIMINISHING CONSIDERABLY. LOW PRES IS THEN FCST TO DEVELOP OFF
THE U.S. EAST COAST THU-FRI AND LIFT TO THE NNE WITH ASSOCIATED
CDFNT MOVING TO THE EAST OF 70W BY NEXT FRI DEC 16. DUE TO
BLOCKING RIDGE OVER THE EAST ATLC IT IS UNKNOWN AT THIS TIME
WHETHER THIS FRONT WILL BE ABLE TO CLEAR THE LOCAL AREA OR NOT
NEXT WEEKEND. GIVEN THE BLOCKING PATTERN WOULD EXPECT THIS LOW
PRES TO BE SLOW MOVER AND GENERATE SIGNIFICANT WAVE ACTION OVR THE
WRN ATLC WITH A SIG SWELL EVENT ARRIVING HERE SOMETIME NEXT
WEEKEND.


&&

.AVIATION...VFR WITH ISOLD SHRA EXPECTED MAINLY ACROSS
TIST/TISX/TNCM/TKPK THRU FRIDAY MORNING. THEN...ADDITIONAL MOISTURE
WILL MOVE INTO THE FLYING AREA ON FRIDAY AFTERNOON...PRODUCING
SCT-BKN CIGS AND SCT SHRA. BRIEF MVFR CONDS POSSIBLE OVER TJMZ AND
TJPS BETWEEN 09/18-21Z. LOW LEVEL WINDS FROM THE EAST-NORTHEAST AT
10-20 KT WITH HIGHER GUSTS AFTER 09/14Z.

&&

.MARINE...WINDS AND SEAS EXPECTED TO INCREASE THIS AFTERNOON
THROUGH MONDAY IN ENE WIND WAVES AND MODERATE NNW SWELLS. THESE
SWELLS WILL BEGIN TO REACH THE ATLC COASTAL TONIGHT AND PEAK SAT
MORNING INCREASING THE RISK OF RIP CURRENTS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 83 73 85 76 / 70 20 50 50
STT 78 76 79 75 / 50 10 50 50

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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
335 PM AST FRI JAN 9 2015

.DISCUSSION...NUMEROUS SHOWERS ON AND NORTHWARD FROM PR COAST ARE
MOVING WESTWARD WHILE THE 700 MB TROUGH IN THE NORTHEAST CARIBBEAN
IS MOSTLY FREE OF SHOWERS. CURRENT RADARS ON LESSER ANTILLES SHOW
THAT SHOWERS ARE ONLY INCREASING AGAIN ONLY AS FAR NORTH AND WEST
AS DOMINICA WHERE PRECIPITABLE WATER INCREASES TO 1.5 INCHES. WE
CURRENTLY HAVE OUR AREA ALMOST RAIN-FREE LATE TONIGHT WHICH IS NOT
CONSISTENT WITH RECENT HISTORY BUT WE HAVEN/T HAD A TROUGH LIKE
THIS WITH SUBSIDENCE BEHIND IT IN AWHILE. NOT ENOUGH REASON TO
CHANGE THE DRY FORECAST SO LEFT IT AS IS.

PRECIPITABLE WATER REMAINS ABOVE SEASONAL LEVELS POSSIBLY THROUGH
NEXT WEEK BUT A TROUGH AS SIGNIFICANT AS THE ONE WE HAVE TODAY IS
NOT APPARENT IN MODELS. WE DO HAVE A 250 MB TROUGH PASSING BY ON
SAT (TOMORROW) BUT THE TROUGH IS NOT DEEP ENOUGH TO INCREASE
SHOWERS MUCH. EVEN AS LOW AS 500 MB WE WILL HAVE A RIDGE. SO
SCATTERED SHOWERS STILL SEEM APPROPRIATE ATTM.

&&

.AVIATION...NMRS SHRA ON AND N OF PR COAST HAS NOT CAUSED MUCH
MVFR AND DO NOT EXPECT IT TO. DRY TROUGH APPROACHING FOR TONITE
THEN ISOLD/SCT SHRA SAT. WINDS BLO FL150 E 12-24 KT DECR ESE 10-18
KT ON SAT.

&&

.MARINE...A 12-13-FOOT NORTHWEST SWELL CURRENTLY AT BUOY 41046 WILL
DECAY TO 8 FT IN ATLANTIC PR WATERS ON SAT MORNING AND WILL BE
RISING AT BUOY 41043 AND PR WATERS SHORTLY AFTER SUNSET. MODELS
LOOK A FEW HOURS EARLY INCREASING THE SEAS THIS AFTERNOON BUT
LOOKED BETTER BY EVENING AND RELIED PRIMARILY ON WNAWAVE4 THROUGH
SUNDAY. HOWEVER KEPT THAT GRID AS IS BEYOND SUN EVE AS CAUTION
SEEMS PRUDENT IN THAT MODELS HAVE BEEN PUSHING BACK THE START OF
AND THE INTENSITY OF TRADE WINDS THIS WEEKEND.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 83 76 83 / 20 50 50 50
STT 74 86 75 85 / 10 50 50 40

[cycloneye]

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
417 AM AST SAT JAN 10 2015

.SYNOPSIS...STRONG ATLC RIDGE WILL CREATE WINDY CONDITIONS SUN-TUE.
RIDGE THEN WEAKENS AS LOW PRES FORMS OFF OF THE U.S. SOUTHEAST
COAST WITH WINDS DIMINISHING. ASSOCIATED CDFNT EXPECTED TO MAKE
IT THROUGH THE AREA NEXT SAT.


&&

.DISCUSSION...DAY WILL START OUT QUITE DRY UNDER FULL SUNSHINE.
ISOLD-SCT AFTERNOON SHOWERS ARE POSSIBLE MAINLY OVR NORTHEAST PR.
HI-RES MODELS SUGGEST SOME LATE DAY SHALLOW CONVECTION OVR NW PR.
NOT QUITE SURE ABOUT THIS GIVEN DRYNESS AND UNFAVORABLE TIME OF
THE YEAR BUT LOW-LEVEL STEERING FLOW LOOKS FVRBL. LOCAL PRES
GRADIENT BEGINS TO TIGHTEN TONIGHT WITH TRADES STRENGTHENING
BUT THIS DOES NOT RESULT IN ANY SIG MOISTURE ADVECTION. IN
FACT...MODELS SHOW A SIG LOW-MID LEVEL DRY SLOT PUNCHING INTO THE
AREA FROM THE EAST SUNDAY WHICH CAN BE SEEN ON TPW IMAGERY NEAR
19N 53W. THIS COULD HAVE FIRE WX IMPLICATIONS FOR SUNDAY. WINDS
REALLY STRENGTHEN MON AS 1037 MB ARCTIC HIGH BUILDS ACROSS THE
ATLC. .FIRE WEATHER...CONTEMPLATING THE ISSUANCE OF A FIRE WX WATCH FOR
THE SOUTH COASTAL PLAIN FOR SUNDAY DUE TO STRONG WINDS AND
LOWERING HUMIDITIES AS GUIDANCE INDICATES A LOW-MID LEVEL DRY SLOT
MOVING IN. STABILITY WILL ALSO BE ON THE DECREASE MEANING MORE
UNSTABLE CONDITIONS THAT COULD ENHANCE THE FIRE WX POTENTIAL. WILL
AWAIT 06Z GFS GUIDANCE BEFORE ISSUING ANYTHING.MOISTURE DEEPENS TO 500 MB AS SUBSIDENCE INVERSION ERODES.
SHOWERS AND EVEN T-STORMS APPEAR LIKELY ON MONDAY ESPECIALLY ERN
PR...USVI AND ADJACENT WATERS. SFC RIDGE SHIFTS EAST TUE WITH PRES
GRADIENT LOOSENING SOMEWHAT. THIS TREND CONTINUES WED WITH RIDGE
WEAKENING FURTHER THU THROUGH THE END OF NEXT WEEK AS LOW PRES
FORMS OFF OF THE U.S. SOUTHEAST COAST. THIS LOW AND ASSOCIATED
CDFNT ARE SLOW TO MOVE EAST BUT MAJORITTY OF GEFS ENSEMBLE MEMBERS
BRING THE FRONT THROUGH THE AREA SAT. DUE TO DEVELOPING LONG FETCH
SRLY FLOW AHEAD OF CDFNT SFC TEMPS COULD HIT RECORD LEVELS ON FRI
BEFORE CFNT CROSSES THE AREA SAT. LOW PRES AND ASSOCIATED FORCING
WILL BE WEAKENING WITH TIME SO AM NOT TOO CONCERNED ABOUT HEAVY
RAINS WITH THIS FRONT.



&&

.AVIATION...MOSTLY VFR THROUGH THE FORECAST PERIOD. HOWEVER...BRIEF
PERIODS OF MVFR CONDITIONS ARE POSSIBLE...AS ISOLATED TO SCATTERED
SHRA IS EXPECTED TO DEVELOP ACROSS MUCH OF THE FLYING AREA IN THE
AFTERNOON. MOUNTAIN OBSCURATIONS EXPECTED OVER EASTERN PR. LOW LEVEL
WINDS FROM THE EAST-SOUTHEAST AT 10-15 KT WITH SEA BREEZE VARIATIONS
AFTER 10/14Z.


&&

.MARINE...NNW FORERUNNERS ARE ARRIVING AT BUOY 41053. THESE SWELLS
EXPECTED TO PEAK LATER THIS MORNING AND THEN GRADUALLY SUBSIDE.
WINDS AND SEAS THEN BUILD LATE TONIGHT THROUGH TUE MORNING IN
STRONG TRADES AND ENE WIND WAVES.

&&

.FIRE WEATHER...CONTEMPLATING THE ISSUANCE OF A FIRE WX WATCH FOR
THE SOUTH COASTAL PLAIN FOR SUNDAY DUE TO STRONG WINDS AND
LOWERING HUMIDITIES AS GUIDANCE INDICATES A LOW-MID LEVEL DRY SLOT
MOVING IN. STABILITY WILL ALSO BE ON THE DECREASE MEANING MORE
UNSTABLE CONDITIONS THAT COULD ENHANCE THE FIRE WX POTENTIAL. WILL
AWAIT 06Z GFS GUIDANCE BEFORE ISSUING ANYTHING.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 83 76 83 73 / 50 50 50 70
STT 86 75 85 75 / 50 50 40 50

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
218 PM AST SAT JAN 10 2015

.SYNOPSIS...AT UPPER LEVEL...WEAK TROUGH WILL DISSIPATED TONIGHT.
UPPER LEVEL RIDGE WILL DOMINATES THE LOCAL REGION THROUGH AT LEAST
MID NEXT WEEK. AT THE SURFACE...STRONG HIGH PRESSURE WILL
DOMINATES THE LOCAL REGION.

&&

.DISCUSSION...RELATIVELY DRY CONDITIONS PREVAILED ACROSS PUERTO
RICO AND THE U.S. VIRGIN ISLANDS LATE THIS MORNING AND EARLY THIS
AFTERNOON. LATER...SHOWERS DEVELOPED OVER THE WESTERN INTERIOR AND
WEST SECTIONS OF PUERTO RICO IN THE VICINITY OF MAYAGUEZ.
A LINE OF CLOUDINESS DEVELOPED BETWEEN EL YUNQUE RAINFOREST AND
THE SAN JUAN METROPOLITAN AREA. REST OF PUERTO RICO REMAINED UNDER
MOSTLY SUNNY SKIES. SOME SHOWERS WILL DEVELOP THE REST OF THIS
AFTERNOON OVER THE CORDILLERA CENTRAL...BUT NO SIGNIFICANT
RAINFALL ACCUMULATION IS EXPECTED.

NEXT FEW DAYS LOCAL AREA WILL REMAIN UNDER THE INFLUENCE OF A
HIGH PRESSURE SYSTEM WHICH WILL LIMIT THE SHOWER ACTIVITY MOST
DAYS. HOWEVER...AN AREA OF DEEP MOISTURE EMBEDDED IN THE TRADE
WINDS IS EXPECTED TO AFFECT THE REGION LATE SUNDAY INTO
MONDAY...WHICH WILL INCREASE THE CHANCES FOR SHOWERS ACROSS THE
AREA. AFTER THAT...STRONG HIGH PRESSURE WILL TAKE CONTROL OF THE
WEATHER LOCALLY...WITH AN INCREASE IN WINDS EXPECTED MONDAY AND
BEYOND. EXCEPT FOR SUNDAY...WHEN PRECIPITABLE WATER VALUES WILL
INCREASE TO NEAR 1.9 INCHES...NORMAL VALUES ARE EXPECTED FOR THE
REMAINDER OF NEXT WEEK.

&&

.AVIATION...TEMPO MVFR CONDITIONS EXPECTED OVER TJMZ AND TJBQ
THROUGH AT LEAST 10/22Z. REST OF TERMINALS...VFR CONDITIONS ARE
EXPECTED TO PREVAIL. LOW LEVEL WINDS WILL BE MAINLY FROM THE EAST
TO SOUTHEAST AT 10 TO 20 KT.

&&

.MARINE...NORTH SWELLS HAVE ARRIVED AT BUOY 41053 IN SAN JUAN. THESE
SWELLS EXPECTED TO PEAK LATER TODAY. IN ADDITION...BUOY 41043
180NM NORTHEAST OF SAN JUAN CONTINUE SHOWING SWELLS OF NEAR 10
FEET AND 13 SECONDS. THESE SWELLS ARE EXPECTED TO CONTINUE
INVADING THE LOCAL COASTAL WATERS THROUGH AT LEAST SUNDAY
MORNING...PRODUCING BREAKING WAVE BETWEEN 10 TO 14 FEET. AS A
RESULT...A HIGH SURF ADVISORY HAS BEEN ISSUED THROUGH 4 AM AST
SUNDAY. REFER TO COASTAL HAZARD MESSAGE PRODUCTS FOR LATEST
INFORMATION. SMALL CRAFT ADVISORIES CONTINUE IN EFFECT FOR MOST
COASTAL WATERS.


&&

.FIRE WEATHER...FIRE WEATHER WATCH REMAINS IN EFFECT FROM SUNDAY MORNING
THROUGH SUNDAY AFTERNOON FOR STRONG WINDS AND LOW HUMIDITIES
FOR FIRE WEATHER ZONE 014. REFER TO FIRE WEATHER MESSAGE PRODUCT
FOR LATEST INFORMATION.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 83 73 83 / 50 50 70 70
STT 75 79 75 79 / 50 40 50 50

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
411 AM AST SUN JAN 11 2015

.SYNOPSIS...STRONG HIGH PRES OVER THE ATLC WILL SUPPORT WINDY
CONDITIONS THROUGH TUESDAY. LOW PRES FORMS OVER THE WRN ATLC WITH
A CDFNT EXPECTED TO MOVE THROUGH THE AREA NEXT SATURDAY.

&&

.DISCUSSION...SHOWERS EXPECTED TO DISSIPATE QUICKLY AFTER 12Z AS
LOW-MID LEVEL DRY SLOT CURRENTLY OVER THE LEEWARD ISLANDS MOVES
OVERHEAD AND DRIES THINGS OUT. ALSO...WEAK SHORTWAVE RIDGE WILL
BUILD IN ALOFT SUPPORTING UPPER LEVEL CONVERGENCE AND DRYING. THE
DRYING WILL ALSO BE AUGMENTED/ENHANCED ON THE SOUTH COAST WHERE
MODELS INDICATE ENE DOWNSLOPE WINDS AT THE SFC. A 0410Z SJU ACARS
SOUNDING SHOWED 925 MB WINDS AT 25-KT OR 5-KT STRONGER THAN
SUGGESTED BY 00Z GFS. STRONG HIGH PRES OF ARCTIC ORIGIN WILL BUILD
ACROSS THE ATLC NEXT FEW DAYS AND SUPPORT WINDY TO VERY WINDY
CONDITIONS THROUGH TUE. SHOWERS WILL BECOME MORE FREQUENT TONIGHT
AND MONDAY ESPECIALLY OVR WINDWARD AREAS AND OVER WATER.

HIGH PRES SHIFTS EAST TUE NIGHT WITH LOCAL PRES GRADIENT LOOSENING
QUICKLY AND WINDS DIMINISHING. THIS WILL ALSO LEAD TO A DECREASE
IN TRADE SHOWER ACTIVITY. WINDS DIMINISH FURTHER THU THROUGH FRI
NIGHT AS LOW PRES FORMS OVR THE WRN ATLC...TRANSLATES EAST AND
LOCAL AREA BECOMES UNDER COL REGION. VERY WARM FRI UNDER LONG
FETCH SRLY FLOW AHEAD OF CDFNT. CDFNT CROSSES THE AREA SAT WITH
NORTHERLIES ESTABLISHING BRINGING COOLER TEMPS AND SHOWERS TO THE
NORTH COAST.


&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED ACROSS ALL THE TERMINALS
DURING THE NEXT 24 HOURS. HOWEVER...PASSING SHRA THROUGH THE DAY
ACROSS THE LEEWARD ISLANDS...VCSH AT JSJ AND USVI TERMINALS
DURING SUNDAY MORNING...WITH BRIEF SCT/BKN CIGS AND MOUNTAIN
OBSCURATIONS ACROSS EASTERN PR. IN THE AFTERNOON VCSH IN AND AROUND
JBQ/JMZ. LOW LEVEL EAST WINDS 15-25 KT.


&&

.MARINE...NORTH SWELLS WILL CONTINUE TO SUBSIDE TODAY BUT WINDS
WILL STRENGTHEN SIGNIFICANTLY WITH 20-25 KT WINDS EXPECTED ON
MONDAY. VERY ROUGH SEAS EXPECTED ESPECIALLY MON-TUE IN ENE WIND WAVES.
WINDS AND SEAS IMPROVE TUE NIGHT ON THROUGH THE END THE WEEK UNTIL
CDFNT REACHES THE LOCAL AREA NEXT SATURDAY.


&&

.FIRE WEATHER...MODELS NOW SHOW MORE OF A ENE FLOW AT THE SFC
TODAY WHICH IS DOWNSLOPE ON THE SOUTH COAST AND TYPICALLY RESULTS
IN VERY LOW RH`S AT CAMP SANTIAGO. SIMILAR EVENTS IN THE PAST HAVE
RESULTED IN MIN_RH`S IN THE 30S THERE. GIVEN THE ALREADY STRONGER
LOW-LEVEL FLOW SEEN ON A RECENT ACARS SOUNDING THAN SUGGESTED BY
GFS THIS BOOSTS MY CONFIDENCE THAT BOTH THE RH AND WIND SPEED
CRITERIA WILL BE MET AT CAMP SANTIAGO THIS AFTERNOON. ALTHOUGH
WINDS BECOME STRONGER ON MONDAY...MOISTURE IS EXPECTED TO ADVECT
QUICKLY PREVENTING RH`S FROM REACHING CRITICAL LEVELS. SOME DRYING
IS EXPECTED TUE BUT NOT ENOUGH TO BRING RH`S DOWN LOW ENOUGH.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 73 82 72 / 50 70 70 50
STT 85 75 85 75 / 40 50 50 40

[cycloneye]

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SAN JUAN PR
437 AM AST SUN JAN 11 2015

...RED FLAG CONDITIONS LIKELY ON THE SOUTH COASTAL PLAIN TODAY...

.WINDS WILL BE STRENGTHENING RAPIDLY TODAY WITH CRITICAL FIRE
WINDS EXPECTED. A LOW-MID LEVEL DRY SLOT CURRENTLY OVER THE
LEEWARD ISLANDS WILL MOVE INTO THE LOCAL AREA THIS AFTERNOON AND
SUPPRESS CLOUD AND SHOWER DEVELOPMENT. IN ADDITION...EAST NORTHEAST
DOWNSLOPE WINDS ARE EXPECTED ON THE SOUTH COAST WHICH WILL ACT TO
ENHANCE DRYING AT THE SURFACE.

PRZ014-111645-
/O.UPG.TJSJ.FW.A.0001.150111T1400Z-150111T2100Z/
/O.NEW.TJSJ.FW.W.0001.150111T1500Z-150111T2100Z/
SOUTH COASTAL PLAINS AND MONA ISLAND-
437 AM AST SUN JAN 11 2015

...RED FLAG WARNING IN EFFECT FROM 11 AM THIS MORNING TO 5 PM AST
THIS AFTERNOON FOR STRONG WINDS AND LOW HUMIDITIES FOR FIRE
WEATHER ZONE 014...

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT FROM 11 AM THIS MORNING TO 5 PM AST
THIS AFTERNOON. THE FIRE WEATHER WATCH IS NO LONGER IN EFFECT.

* 20-FOOT WINDS: EAST OR EAST NORTHEAST WINDS 20 MPH WITH GUSTS
TO 30 MPH.

* KEETCH-BYRAM DROUGHT INDEX (KBDI): 638 AT CAMP SANTIAGO.

* 10-HR FUEL MOISTURE: 7 TO 8 PERCENT.

* MINIMUM RELATIVE HUMIDITY: LESS THAN 40 PERCENT AT CAMP SANTIAGO.

* IMPACTS...PEOPLE ARE URGED TO EXERCISE EXTREME CARE WITH
RESPECT TO OUTDOOR ACTIVITIES THAT COULD CAUSE WILDFIRES.
AVOID ANY EQUIPMENT THAT CAN CAUSE SPARKS NEAR DRY GRASS OR
BRUSH. DO NOT TOSS CIGARETTES ON THE GROUND. REPORT NEW
WILDFIRES QUICKLY TO THE NEAREST FIRE DEPARTMENT OR LAW
ENFORCEMENT OFFICE. OUTDOOR BURNING IS PROHIBITED.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL OCCUR WITHIN THE NEXT
24 HOURS. A COMBINATION OF FUELS AND WEATHER CONDITIONS SUPPORT
EXTREME FIRE DANGER AND/OR FIRE BEHAVIOR.

&&

$$

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
232 PM AST SUN JAN 11 2015

.SYNOPSIS...AT UPPER LEVEL...UPPER LEVEL RIDGE WILL DOMINATES
THE LOCAL REGION THROUGH AT LEAST MID NEXT WEEK. AT THE
SURFACE...STRONG HIGH PRESSURE WILL DOMINATES THE LOCAL REGION.
PATCHES OF LOW LEVEL MOISTURE WILL CONTINUE TO MOVE ACROSS THE
REGION FROM TIME TO TIME.

&&

.DISCUSSION...AFTER A CLOUDY AND SHOWERY MORNING..MAINLY ALONG THE
NORTH AND EAST SECTIONS OF PUERTO RICO...A SLOT OF DRY AIR MOVED
FROM THE EAST...LEAVING PARTLY CLOUDY SKIES ACROSS MOST OF THE
AREA. LATEST VISIBLE SATELITE IMAGES SHOWS AN AREA OF CLOUDINESS
DEVELOPED OVER THE SOUTHWEST SECTION OF PUERTO RICO...WITH SOME
CLOUDS ALSO NOTED IN THE VICINITY OF SAINT THOMAS AND SAINT JOHN.
ANOTHER PATCH OF LOW LEVEL MOISTURE WILL AFFECT THE REGION TONIGHT
INTO EARLY MONDAY...INCREASING SOMEWHAT ONCE AGAIN THE CHANCES FOR
PASSING SHOWERS.

REST OF THE WEEK LOOKS SIMILAR...WITH PASSING SHOWERS AFFECTING
THE NORTH AND EAST SECTIONS OF PUERTO RICO AND THE U.S. VIRGIN
ISLANDS DURING THE OVERNIGHT AND EARLY MORNING HOURS. HIGH
PRESSURE WILL CONTINUE TO DOMINATES THE LOCAL REGION FOR MOST OF
THE WEEK.

&&

.AVIATION...VFR XCP BRF MVFR AND MTN OBSC IN SCT SHRA THRU MON NITE.
WIND BLO FL150 E 16-30 KT.

&&

.MARINE...WINDS AND CHOPPY SEAS WILL INCREASE TODAY AS TRADE WINDS
INCREASE IN RESPONSE TO HIGH PRESSURE MOVING OFFSHORE OF U.S. MID-
ATLANTIC COAST. SMALL CRAFT ADVISORIES CONTINUE IN EFFECT FOR MOST
COASTAL WATERS.

&&

.FIRE WEATHER...RLEATIVE HUMIDITY AT CAMP SANTIAGO REACHED 40
PERCENT AROUND 2 PM AST WITH WINDS OF 16 MPH GUSTING TO 24 MPH
OBSERVED. RED FLAG WARNING WILL CONTINUE TO IN EFFECT THROUGH 5 PM
AST THIS AFTERNOON. MOISTURE IS EXPECTED TO ADVECT QUICKLY
PREVENTING RH`S FROM REACHING CRITICAL LEVELS MONDAY. SOME DRYING IS
EXPECTED TUESDAY BUT NOT ENOUGH TO BRING RH`S DOWN LOW ENOUGH.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 73 82 72 84 / 70 70 50 30
STT 75 85 75 86 / 50 50 40 20

[cycloneye]

AFDSJU

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
445 AM AST MON JAN 12 2015

.SYNOPSIS...STRONG WRN ATLC SFC RIDGE WILL SHIFT EAST INTO THE
ECNTRL ATLC TUE WITH WINDS DIMINISHING TUE AFTERNOON THROUGH THE
END OF THE WEEK. A SHEARLINE WILL MOVE THROUGH THE AREA SAT WITH
SHIFTING WINDS.


&&

.DISCUSSION...STRONG ATLC SFC RIDGE WILL MAINTAIN A VERY TIGHT
PRES GRADIENT TODAY AND SUPPORT WINDY CONDITIONS. MOISTURE
ADVECTION IS FCST THROUGH EARLY THIS AFTERNOON WITH SCT-NMRS
SHOWERS ESPECIALLY NORTHEAST PR. A DRYING TREND BEGINS AFTER 18Z
TODAY AND LASTS THROUGH 18Z TUE WITH MOST SHOWERS LIKELY TO BE
GONE AFTER 06Z TONIGHT. ATLC RIDGE SHIFTS FURTHER EAST INTO ECNTRL
ATLC TUE NIGHT AND THROUGH THE REST OF THE WEEK WITH TRADE WINDS
DIMINISHING CONSIDERABLY. FLOW VEERS TO ESE MID WEEK AND SSE BY
LATE WEEK PROMOTING A WARMING TREND. AFTERNOON DEEP CONVECTION MAY
DEVELOP WED THROUGH FRI AFTERNOONS OVR NWN/NCNTRL PR AS LOW-MID
LEVEL HEIGHT FALLS PROMOTE MOISTURE TRANSPORT AND FURTHER
WEAKENING OF THE SUBSIDENCE INVERSION. RECORD HIGHS ARE POSSIBLE
ON FRI AS FLOW BECOMES MORE SSE BEFORE WINDS SHIFT TO THE NE
SATURDAY WITH THE PASSAGE OF A PREFRONTAL TROUGH/SHEARLINE. ACTUAL
CDFNT OR DEWPOINT DISCONTINUITY APPEARS TO REMAIN NORTH OF THE
AREA BUT SHIFTING WINDS WILL BRING COOLER TEMPS WITH A CHANGE IN
AIR MASS BY EARLY NEXT WEEK.

&&

.AVIATION...MAINLY VFR CONDITIONS EXPECTED ACROSS ALL THE TERMINALS
THROUGH THE FORECAST PERIOD. HOWEVER...PASSING SHRA W/BRIEF SFC WND
GUSTS PSBL UP TO 25 KT AT ALL TAF SITES EXCP AT TJMZ/TJPS.
ALSO...MTN TOP OBSC IN SCT SHRA LOW SCUD CLDS OVR ERN PR THRU
12/14Z. EASTERLY WINDS 15-30 KTS BELOW 5 KFT.


&&

.MARINE...WINDS 20-25 KT TODAY AND TONIGHT WITH SEAS 7-9 FT. WINDS
AND SEAS GRADUALLY SUBSIDE TUE NIGHT THROUGH THE END OF THE WEEK.
T-STORMS MAY DEVELOP WED-FRI AFTERNOONS OFF OF THE NW AND NCNTRL
PR COASTS.


&&

.FIRE WEATHER...DESPITE STRONG WINDS TODAY...MOISTURE ADVECTION IS
FCST THROUGH EARLY THIS AFTERNOON AND CLOUDS ARE LIKELY TO KEEP
TEMPS COOLER AND THUS RH`S HIGHER THAN YDAY. SIG DRYING FCST FOR
TONIGHT THROUGH 18Z TUE AND STRONG PRES GRADIENT WILL KEEP
ATMOSPHERE WELL MIXED AND TEMPS UP PREVENTING ANY RH RECOVERY FROM
TODAY`S MIN. ALSO...STRONGER THAN NORMAL ENE DOWNSLOPE FLOW ON THE
SOUTH COAST WILL LIKELY RESULT IN WARMING/DRYING NEAR THE SFC. SO
TUE...IS LIKELY TO START OUT WARM AND DRY WITH LOW MAX RH`S. WINDS
STILL LOOK TO BE STRONG ENOUGH TO SUPPORT RED FLAGS EARLY BEFORE
THEY START WEAKENING MORE RAPIDLY IN THE AFTERNOON. A FIRE WX
WATCH WILL BE ISSUED FOR TUE.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 83 77 84 78 / 70 50 20 30
STT 84 77 86 78 / 50 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
259 PM AST MON JAN 12 2015

.SYNOPSIS...AT UPPER LEVEL...UPPER LEVEL RIDGE WILL DOMINATES
THE LOCAL REGION THROUGH AT LEAST MID NEXT WEEK. AT THE
SURFACE...STRONG HIGH PRESSURE WILL DOMINATES THE LOCAL REGION.
PATCHES OF LOW LEVEL MOISTURE WILL CONTINUE TO MOVE ACROSS THE
REGION FROM TIME TO TIME. A SHEAR LINE EXPECTED TO AFFECT THE
LOCAL AREA SATURDAY WITH WINDS SHIFTING.

&&

.DISCUSSION...PASSING SHOWERS AFFECT MOST OF PUERTO RICO AND THE
U.S. VIRGIN ISLANDS THIS MORNING AND EARLY THIS AFTERNOON.
LATEST 12/12Z TJSJ SOUNDING SHOWED PRECIPITABLE WATER VALUES OF
1.75 INCHES. NEXT 24 HOURS...A DRIER AIR MASS IS EXPECTED TO MOVE
ACROSS THE REGION WITH FORECAST SOUNDING SHOWING PW VALUES
DECREASING TO AS LOW AS 1.0 INCH BY TUESDAY AFTERNOON.
THEREFORE...LIMITED SHOWER ACTIVITY IS EXPECTED FOR TUESDAY. HIGH
PRESSURE CONTINUES DOMINATING THE LOCAL REGION...AND WILL CONTINUE
TO DO SO THROUGH AT LEAST THE END OF THE WEEK.

WINDS NEXT FEW DAYS WILL SHIFT MORE TO THE SOUTHEAST...WHICH WILL
PROMOTE HIGHER THAN NORMAL TEMPERATURES ALONG THE NORTHERN SLOPES
OF PUERTO RICO FROM MID WEEK THROUGH FRIDAY. IN THE LONG TERM...A
SHEAR LINE/FRONTAL BOUNDARY IS FORECAST TO AFFECT THE REGION BY
NEXT WEEKEND. MODEL SUGGEST A SHIFT IN WIND DIRECTION EXPECTED
SUNDAY...WITH THE RETURN TO A MORE NORTHEASTERLY WIND BY THAT
TIME.

&&

.AVIATION...MAINLY VFR CONDITIONS EXPECTED ACROSS ALL THE TERMINALS
THROUGH THE FORECAST PERIOD. HOWEVER...PASSING SHRA W/BRIEF SFC WND
GUSTS PSBL UP TO 35 KT AT ALL TAF SITES. SHRA ACTIVITY WILL DECREASE
DURING THE NIGHT HOURS. GUSTY WINDS HAVE BEEN REPORTED AT
TJSJ/TJBQ/TNCM/TIST/TISX. EASTERLY WINDS AT 15-30 KTS WITH HIGHER
GUSTS IN THE VICINITY OF SHRA. OVERNIGHT WINDS MAINLY FROM THE EAST
BETWEEN 5 AND 15 KT.

&&

.MARINE...SMALL CRAFT ADVISORIES ARE IN EFFECT ACROSS MOST OF THE
LOCAL WATERS...MARINERS CAN EXPECT WINDS UP TO 22 KNOTS AND SEAS
MAINLY RANGING FROM 6 TO 8 FEET. BEACH GOERS SHOULD EXERCISE
CAUTION DUE TO STRONG RIP CURRENTS ACROSS MUCH OF THE NORTH...
EAST AND SOUTH COASTS OF PUERTO RICO AND U.S. VIRGIN ISLANDS.

&&

.FIRE WEATHER...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH
TUESDAY AFTERNOON FOR SOUTH COASTAL PLAINS AND MONA ISLAND WILL BE
IN EFFECT. REFER TO LATEST RFWSJU PRODUCT FOR LATEST INOFRMATION.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 77 84 78 83 / 50 20 30 30
STT 77 86 78 84 / 20 20 20 20

[cycloneye]

AFDSJU

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
555 AM AST TUE JAN 13 2015

.UPDATE...CFW UPDATED TO ACCOUNT FOR LATEST OBS AND MODEL TRENDS.
MOST SIGNIFICANT CHANGES WERE MADE AFTER TONIGHT WITH SEAS
DROPPING BELOW 7 FT LATE TONIGHT AND SEAS GRADUALLY IMPROVING
THROUGH THE END OF THE WEEK.

&&

.PREV DISCUSSION... /ISSUED 433 AM AST TUE JAN 13 2015/

.SYNOPSIS...ATLC SFC RIDGE WILL SHIFT FARTHER EAST WITH TRADE
WINDS GRADUALLY DIMINISHING THROUGH THE END OF THE WEEK. LOW PRES
FORMS OVR THE SW ATLC WED WITH A SHEARLINE MOVING THROUGH THE AREA
SAT.

&&

.DISCUSSION...SHORTWAVE RIDGE ALOFT WILL BUILD OVERHEAD TODAY
AND SUPPORT UPPER LEVEL CONVERGENCE AND SHARP DRYING THROUGH MOST
OF THE DAY. TRADE WINDS ALBEIT WEAKER TODAY STILL SUPPORT BREEZY
CONDITIONS. HEIGHT FALLS TONIGHT IN ADVANCE OF AN UPPER LEVEL
SHORTWAVE-TROUGH CROSSING 80W ATTM WILL PROMOTE MOISTURE TRANSPORT
WITH SHOWERS RETURNING TO THE AREA. WHILE UPPER LEVEL RIDGE BUILDS
THROUGH FRI...SFC-700 MB RIDGE WEAKENS STEADILY INTO EARLY NEXT
WEEK AND THIS ALLOWS FOR FURTHER WEAKENING OF THE SUBSIDENCE
INVERSION AND THUS MOISTENING OF THE LOW-MID LEVELS. WINDS
GRADUALLY VEER FROM EAST TODAY TO SOUTHEAST BY FRI AHEAD OF A
PREFRONTAL TROUGH PROMOTING A SIG WARM UP WITH RECORD HIGHS LIKELY
ON FRI. SHEARLINE MOVES THROUGH THE AREA SAT WITH WINDS SHIFTING
TO NE PROMOTING COOLER TEMPERATURES AND MOISTURE DEEPENING INTO
EARLY NEXT WEEK WITH FREQ SHOWERS ON THE NORTH COAST.

&&

.AVIATION...MAINLY VFR CONDITIONS EXPECTED ACROSS ALL THE
TERMINALS THROUGH THE FORECAST PERIOD. MOISTURE EAST OF THE
LEEWARD ISLANDS WILL INCREASE LATE IN THE FCST PERIOD...SPREADING
TO THE USVI AND EASTERN PR TERMINALS...VCSH AND BRIEF MVFR
CONDITIONS ARE POSSIBLE. SFC EASTERLY WINDS AT 15-20 KTS WITH
HIGHER GUSTS AFTER 14Z.

&&

.MARINE...STILL BREEZY TODAY WITH WINDS NEAR 20KT AND SEAS 6-8
FT OFFSHORE WATERS. WINDS AND SEAS GRADUALLY SUBSIDE THROUGH THE
END OF THE WEEK.

&&

.FIRE WEATHER...SHARP DRYING EXPECTED TODAY AS UPPER LEVEL
CONVERGENCE INCREASES. SFC DEWPOINTS AT ALL RAWS SITES ALREADY
2-4F DEGS LOWER AND RH`S AS MUCH AS 8% LOWER THAN 24 HRS AGO.
TRADE WINDS ALBEIT WEAKER TODAY STILL EXPECTED TO MEET THE RFW
CRITERIA. A 0545Z ACARS SOUNDING SHOWED 925 MB WINDS OF 25-KT WITH
20-25 KT AVG IN THE LOWEST 0-1KM LAYER. ALSO...SIGNS OF THE
SUBSIDENCE INVERSION STRENGTHENING SUPPORTING THE DRYING TREND.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 83 78 82 78 / 40 70 70 50
STT 85 78 84 78 / 40 50 50 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
237 PM AST TUE JAN 13 2015

.SYNOPSIS...RIDGE ALOFT WILL ERODE TONIGHT AND WEDNESDAY AS UPPER
LEVEL SHORTWAVE TROUGH MOVES CLOSER TO THE EASTERN CARIBBEAN. A
MID TO UPPER LEVEL RIDGE PATTERN WILL RETURN TO THE AREA LATE THIS
WEEK. TRADE WINDS WILL WEAKEN TONIGHT AND WEDNESDAY...AS SURFACE
HIGH ACROSS THE CENTRAL ATLANTIC MOVES FURTHER EAST. WINDS ARE
EXPECTED TO BECOME SOUTHEASTERLY FRIDAY AND SATURDAY WITH THE
APPROACH OF A SHEARLINE.

&&

.DISCUSSION...PARTLY CLOUDY SKIES PREVAILED ACROSS THE LOCAL ISLANDS
TODAY...WITH ISOLATED TO LOCALLY SCATTERED SHOWERS OBSERVED ACROSS
THE USVI...VIEQUES...CULEBRA AND THE EAST COASTAL AREAS OF PUERTO
RICO. BREEZE CONDITIONS PREVAILED THROUGH THE DAY...WITH COASTAL
TEMPERATURES IN THE MID 80S.

RIDGE ALOFT WILL ERODE TONIGHT AND WEDNESDAY AS UPPER LEVEL SHORTWAVE
TROUGH...NOW LOCATED OVER THE BAHAMAS AND CUBA...MOVES CLOSER TO THE
EASTERN CARIBBEAN. THIS EVOLVING PATTERN COMBINED WITH PATCHES OF LOW
LEVEL MOISTURE EMBEDDED IN THE TRADES WILL RESULT IN A BETTER CHANCE
OF PASSING SHOWERS ACROSS LOCAL ISLANDS EACH DAY. THEREFORE...EXPECT
THE CONTINUED TREND OF PASSING SHOWERS ACROSS THE USVI...THE EAST AND
NORTH COASTAL PLAINS OF PUERTO RICO TONIGHT THROUGH AT LEAST FRIDAY.
SOME AFTERNOON CONVECTION IS POSSIBLE EACH DAY. SOUTHEASTERLY WINDS
FRIDAY AND SATURDAY MAY RESULT IN WARMER THAN NORMAL TEMPERATURES
ALONG THE NORTH COAST OF PUERTO RICO.

THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK ADDITIONAL SHOWERS ARE
EXPECTED MAINLY ACROSS THE NORTHERN USVI AND THE NORTH COAST OF PUERTO
RICO AS A SHEARLINE AND ASSOCIATED MOISTURE APPROACHES THE LOCAL AREA.

&&

.AVIATION...MAINLY VFR CONDS EXPECTED ACROSS ALL THE TERMINALS THROUGH
THE FORECAST PERIOD. LOW LEVEL MOISTURE IS MOVING ACROSS THE LEEWARD
ISLANDS AND APPROACHING THE USVI/PR...THEREFORE SHRA/VCSH ARE EXPECTED
ACROSS TIST/TISX/TJSJ/TNCM/TKPK TONIGHT WITH BRIEF MVFR CONDITIONS
POSSIBLE. SFC EASTERLY WINDS AT 10-22 KTS WITH HIGHER GUSTS.

&&

.MARINE...STRONG HIGH PRESSURE SYSTEM OVER THE CENTRAL ATLANTIC WILL
SHIFT FARTHER EAST TONIGHT WITH TRADE WINDS GRADUALLY DIMINISHING
OVERNIGHT AND WEDNESDAY. A SHEARLINE WILL MOVE THROUGH THE AREA
SATURDAY. MARINE CONDITIONS SLOWLY IMPROVING.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 77 83 77 83 / 70 70 50 50
STT 73 85 73 85 / 50 50 40 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
518 AM AST WED JAN 14 2015

.SYNOPSIS....RIDGE ALOFT WILL CONTINUE TO ERODE TODAY IN RESPONSE TO
MID TO UPPER LEVEL SHORTWAVE TROUGH MOVING ACROSS THE NORTHEASTERN
CARIBBEAN. HOWEVER...THE UPPER RIDGE IS TO REESTABLISH ITSELF ONCE
AGAIN BY THE END OF THE WORK WEEK AND INTO THE UPCOMING WEEKEND.
SURFACE HIGH PRESSURE RIDGE EXTENDING ACROSS THE REGION FROM THE
CENTRAL ATLANTIC WILL GRADUALLY LOOSEN ITS HOLD OVER THE NEXT FEW
DAYS...AS A FRONTAL TROUGH MOVES FURTHER EAST ACROSS THE WESTERN
ATLANTIC THROUGH FRIDAY. IN DOING SO...THE LOCAL PRESSURE GRADIENT
IS TO WEAKEN RESULTING IN DECREASING TRADE WIND FLOW WITH FAIRLY
LIGHT EAST TO SOUTHEAST WINDS EXPECTED BY FRIDAY AND INTO THE WEEKEND.
A FRONTAL SHEAR LINE IS TO STALL ACROSS THE ATLANTIC JUST NORTHWEST
OF THE REGION BY LATE SATURDAY WITH WEAKLY INDUCED SURFACE TROUGH
TO SET UP ACROSS THE REGION ON SUNDAY AND MONDAY.

&&

.DISCUSSION...SKIES WERE VARIABLY CLOUDY THIS MORNING AS A SURGE
OF LOW TO MID LEVEL MOISTURE AND ACCOMPANYING ISOLATED TO SCATTERED
SHOWERS MOVED WESTWARD ACROSS THE REGION. HOWEVER THE SHOWER ACTIVITY
AFFECT MAINLY THE EAST COASTAL SECTIONS OF PUERTO RICO AS WELL AS
SOME OF THE VIRGIN ISLANDS. SOME HOWERS WERE MODERATE TO LOCALLY
HEAVY AT TIMES DURING THE OVERNIGHT HOURS BUT BY EARLY MORNING
MOST OF THE ACTIVITY WERE OF LIGHT TO MODERATE INTENSITY. LOCAL
WINDS OVER LAND ALSO ALSO DIMINISHED TO 5 TO 10 MPH DURING THE EARLY
MORNING HOURS BUT WERE SLIGHTLY HIGHER WITH THE PASSING SHOWERS.

DURING THE REST OF THE DAY...EXPECT OCCASIONAL PATCHES OF TRADE
WIND MOISTURE TO CONTINUE TO MOVE THROUGH THE REGION. LOCAL FORCING
AND LOCALIZED CONVERGENCE WILL AID IN PRODUCING PERIODS OF SHOWERS
ACROSS PARTS OF THE ISLANDS. HOWEVER...RAINFALL ACCUMULATIONS WILL
NOT BE SIGNIFICANT AS THE SHOWER ACTIVITY WILL BE OF SHORT DURATION.
AS PREVIOUSLY MENTIONED...THE PREVAILING EAST SOUTHEAST TRADE WINDS
WILL CONTINUE TO DIMINISH TODAY AND DURING THE REST OF THE WEEK AS
THE HIGH PRESSURE RIDGE SHIFT FARTHER EAST OF THE REGION. THIS
WILL RESULT IN LESSER MOISTURE CONVERGENCE ACROSS THE REGION AND
DECREASING TRADE WIND SHOWERS ON THURSDAY AND FRIDAY. HOWEVER EXPECT
SUFFICIENT MOISTURE AVAILABLE EACH DAY TO AID IN SOME ISOLATED TO
SCATTERED SHOWERS ACROSS PARTS OF THE ISLANDS ESPECIALLY DURING
THE EARLY MORNING AND MAINLY OVER THE WEST AND NORTHWEST SECTIONS
OF PUERTO RICO DURING THE AFTERNOON HOURS.

FOR THE LONG TERM...MODEL SUGGESTS THAT DURING THE LATTER PART OF
THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK...ADDITIONAL MOISTURE
AND SHOWERS ACTIVITY WILL BE POSSIBLE MAINLY ACROSS THE NORTHERN HALF
OF PUERTO RICO AND THE NORTHERN USVI AS A FRONTAL SHEAR LINE IS TO
STALL JUST NORTH AND WEST OF THE REGION...AND WINDS ARE FORECAST
TO BECOME MORE NORTHEASTERLY BY THE MIDDLE OF NEXT WEEK. STILL
HOWEVER NO WIDESPREAD RAINFALL IS EXPECTED AT THIS TIME.

&&

.AVIATION...BRIEF PERIODS OF MVFR CONDITIONS CAN BE EXPECTED OVER
TIST...TISX AND TJSJ IN PASSING SHOWERS THROUGH 14/16Z. SCATTERED
SHOWERS ARE EXPECTED OVER TIST...TISX...TNCM...TKPK...AND
TJSJ...FROM 14/12Z THROUGH 14/18Z. ELSEWHERE...VFR CONDITIONS ARE
EXPECTED TO PREVAIL. TJSJ 14/00Z SOUNDING INDICATED AN EASTERLY WIND
FLOW UP TO 20 KNOTS ALL THE WAY FROM THE SURFACE TO AROUND 15K
FEET...BECOMING WESTERLY AND STRONGER ALOFT.

&&

.MARINE...SMALL CRAFT ADVISORIES WILL CONTINUE UNTIL 6 AM AST
THIS MORNING AS SEA CONDITIONS HAVE BEGUN TO SHOW SIGNS OF GRADUAL
IMPROVEMENT BASED ON THE LATEST BUOY DATA. SCATTEROMETER WIND
PRODUCTS AS WELL AS THE LOCAL OFFSHORE BUOYS SUGGESTED WINDS OF 15
TO 20 KNOTS...AND SEAS NOW DOWN TO NEAR 7 TO 8 FEET OFFSHORE. NEAR
SHORE SEAS WERE ALSO DOWN TO 6 FEET OR LESS...AND CONTINUE TO SLOWLY
SUBSIDE IN RESPONSE TO THE DIMINISHING LOCAL TRADE WINDS. OVERALL
SEAS ARE FORECAST TO GRADUALLY DECREASE OVER THE NEXT FEW DAYS...WITH
OF 6 FEET OR LESS ACROSS MUCH OF THE LOCAL WATERS. SMALL CRAFT OPERATORS
SHOULD STILL HOWEVER EXERCISE CAUTION DURING THE REST OF TODAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 81 75 82 70 / 60 40 40 30
STT 84 74 85 75 / 50 40 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
236 PM AST WED JAN 14 2015

.SYNOPSIS...UPPER LEVEL SHORTWAVE TROUGH WILL CONTINUE TO DOMINATE
THE LOCAL WEATHER REGIME TONIGHT THROUGH THURSDAY AFTERNOON...WITH
MID TO UPPER LEVEL RIDGE BUILDING IN FRIDAY AND INTO THE UPCOMING
WEEKEND. SURFACE HIGH ACROSS THE CENTRAL ATLANTIC WILL CONTINUE TO
MOVE FURTHER EAST DURING THE NEXT FEW DAYS. SHEARLINE IS EXPECTED
TO APPROACH THE AREA SATURDAY.

&&

.DISCUSSION...PARTLY TO VARIABLY CLOUDY SKIES PREVAILED ACROSS THE
LOCAL ISLANDS TODAY...WITH ISOLATED TO LOCALLY SCATTERED SHOWERS
OBSERVED ACROSS THE USVI...VIEQUES...CULEBRA AND THE EAST AND
NORTH PLAINS OF PUERTO RICO. EARLY THIS AFTERNOON...SCATTERED SHOWERS
ALSO DEVELOPED ACROSS THE NORTHWEST QUADRANT OF PUERTO RICO. COASTAL
TEMPERATURES WERE IN THE MID 80S.

THE LOCAL ISLANDS WILL CONTINUE UNDER THE INFLUENCE OF UPPER LEVEL
SHORTWAVE TROUGH WHICH WILL INTERACT WITH PATCHES OF LOW LEVEL
MOISTURE AND LOCAL EFFECTS TO PRODUCE CLOUDINESS AND SHOWERS ACROSS
PORTIONS OF THE LOCAL ISLANDS TONIGHT THROUGH AT LEAST THURSDAY
AFTERNOON. THEREFORE UNDER THE PREVAILING EASTERLY WIND FLOW...EXPECT
THE CONTINUED TREND OF PASSING SHOWERS ACROSS THE NORTH AND EAST
COASTAL SECTIONS OF THE ISLANDS ESPECIALLY DURING THE MORNING HOURS.
AFTERNOON CONVECTION STILL POSSIBLE.

AS SHORTWAVE TROUGH MOVES AWAY FROM THE AREA THURSDAY NIGHT AND
FRIDAY...MOISTURE EROSION IS EXPECTED WITH A GENERALLY FAIR WEATHER
PATTERN THURSDAY NIGHT AND FRIDAY. SOUTHEASTERLY WINDS EXPECTED
BOTH DAYS...THEREFORE WARMER TEMPS POSSIBLE ALONG THE NORTH COAST.
SATURDAY AND INTO EARLY NEXT WEEK ADDITIONAL SHOWERS ARE EXPECTED
MAINLY ACROSS THE NORTHERN USVI AND THE NORTH COAST OF PUERTO RICO
AS A SHEARLINE AND ASSOCIATED SURFACE TROUGH APPROACH THE LOCAL
AREA.

&&

.AVIATION...SCATTERED SHRA EXPECTED IN OR AROUND TIST...TISX...TNCM...
TKPK...TJSJ...TJBQ...TJMZ THROUGH 14/23Z. ELSEWHERE...VFR CONDITIONS
ARE EXPECTED TO PREVAIL. SURFACE WINDS FROM THE EAST AT 10 TO 20
KNOTS WITH HIGHER GUSTS... AFT 14/23Z BETWEEN 5 AND 10 KNOTS.

&&

.MARINE...SEAS UP TO 6 FEET AND WINDS 15-20KTS. SMALL BOAT OPERATORS
SHOULD EXERCISE CAUTION.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 73 84 72 84 / 40 40 30 30
STT 74 85 74 85 / 40 30 20 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
347 AM AST THU JAN 15 2015

.SYNOPSIS...WEAK SHORT WAVE TROUGH AXIS EXTENDING ACROSS THE
NORTHERN LEEWARD ISLANDS INTO THE EASTERN CARIBBEAN CONTINUED TO
ENHANCE TRADE WINDS SHOWERS ACROSS THE NORTHEASTERN CARIBBEAN.
SOME OF THE SHOWERS AND ASSOCIATED AREAS OF SHALLOW MOISTURE
CONTINUED TO MOVE ACROSS THE COASTAL WATERS AND AFFECT THE EAST
AND SOUTHEAST COASTAL SECTIONS OF THE ISLANDS. SO FAR MOST OF THE
SHOWERS OVER LAND HAVE BEEN OF LIGHT INTENSITY AND OF SHORT DURATION...
WITH NO SIGNIFICANT RAINFALL ACCUMULATIONS NOTED. STRONG SURFACE HIGH
PRESSURE SYSTEM CENTERED OVER THE CENTRAL ATLANTIC WILL CONTINUE TO
SHIFT FARTHER EAST INTO THE EASTERN ATLANTIC THROUGH THE UPCOMING
WEEKEND. THIS IS IN RESPONSE TO A WEAKENING COLD FRONT MOVING ACROSS
THE WESTERN ATLANTIC...AND WHICH IS EXPECTED TO EVENTUALLY STALL
JUST NORTHWEST OF THE REGION BY SATURDAY. THIS FEATURE AND THE STRONG
HIGH PRESSURE RIDGE ACROSS EAST AND CENTRAL ATLANTIC WILL LOCALLY INDUCE
A WEAK LOW LEVEL TROUGH BY SATURDAY AND ON SUNDAY WITH TRADE WINDS THEN
EXPECTED TO BECOME FAIRLY LIGHT FROM THE EAST NORTHEAST.

&&

.DISCUSSION...EXPECT PERIODS OF SHALLOW MOISTURE ADVECTION AND
PASSING SHOWERS TO CONTINUE THROUGH THE MORNING HOURS ACROSS THE
SURROUNDING COASTAL WATERS. SOME SHOWERS WILL CONTINUE TO REACH
SOME OF THE COASTAL AREAS OF THE ISLANDS BUT MOST OF THE ACTIVITY
SHOULD REMAIN OFFSHORE DUE TO MORE DOMINANT LAND BREEZE. DURING
THE REST OF THE DAY..FAIR AMOUNT OF SUNSHINE CAN BE EXPECTED WITH
SOME SHOWERS FORMING DURING THE AFTERNOON MAINLY OVER PARTS OF
THE NORTH CENTRAL INTERIOR AND NORTHWEST SECTIONS OF PUERTO RICO.
OVERALL RAINFALL ACCUMULATIONS SHOULD BE MINIMAL IN MOST AREAS BUT
SOME SHOWERS MAY BE LOCALLY HEAVY ESPECIALLY OVER PARTS OF NORTHWEST
PUERTO RICO LATER IN THE AFTERNOON.

FOR THE REST OF THE WEEK AND INTO THE WEEKEND EXPECT PRETTY MUCH
OF THE SAME WEATHER PATTERN WITH PERIODS OF PASSING EARLY MORNING
SHOWERS AND LIMITED SHOWERS DEVELOPMENT ACROSS THE ISLANDS DURING
THE AFTERNOONS. MOST OF SHOWER DEVELOPMENT WILL BE DIURNALLY AND
LOCALLY INDUCED DUE TO DAYTIME HEATING AND LOCAL TERRAIN FORCING.
LOCAL TRADE WIND SHOULD BECOME FAIRLY LIGHT BY FRIDAY AND OVER THE
UPCOMING WEEKEND. THIS IN TURN SHOULD ALLOW FOR BETTER SEA BREEZE
CONVERGENCE WHICH WILL AID IN SHOWER DEVELOPMENT EACH DAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS CAN BE EXPECTED OVER THE LOCAL
TERMINALS WITH BRIEF PASSING SHOWERS THROUGH 15/18Z. SCATTERED
SHOWERS ARE EXPECTED OVER TIST...TISX...TNCM...TKPK...AND
TJSJ...FROM 15/12Z THROUGH 15/18Z. TJBQ MAY OBSERVE SHOWERS AFTER
15/18Z. LOW LEVEL WINDS WILL BE MAINLY FROM THE EAST SOUTHEAST
INCREASING UP TO 15 KNOTS AFTER 15/13Z.

&&

.MARINE...SMALL CRAFT SHOULD EXERCISE CAUTION ACROSS MOST OF THE LOCAL
WATERS TODAY DUE TO WINDS UP TO 18 KNOTS AND SEAS UP TO 6 FEET MAINLY
OFFSHORE. WINDS AND SEAS WILL HOWEVER CONTINUE TO DIMINISH TO BELOW
6 FEET AND LESS THAN 18 KNOTS BY SATURDAY AND AS THE LOCAL PRESSURE
GRADIENT WEAKENS FOR THE UPCOMING WEEKEND.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 72 84 73 / 40 30 30 20
STT 85 74 85 74 / 30 20 30 30

[cycloneye]

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
305 PM AST THU JAN 15 2015

.SYNOPSIS...
AN UPPER LEVEL TROUGH LOCATED OVER THE LESSER ANTILLES WILL
CONTINUE TO MOVE EASTWARD ALLOWING A MID TO UPPER LEVEL TROUGH TO
ESTABLISH OVER THE LOCAL AREA BY FRIDAY NIGHT THROUGH THE NEXT
WEEK.

THE SURFACE HEIGHT PRESSURE OVER CENTRAL ATLANTIC WILL CONTINUE
TO MOVE EASTWARD AS A SHEARLINE OVER THE WESTERN ATLANTIC APPROACH
THE LOCAL AREA FROM THE WEST. ALSO...AS THE FRONTAL BOUNDARY
APPROACH THE FORECAST AREA WILL INDUCE A WEAK SURFACE TROUGH ON
SATURDAY.

&&

.DISCUSSION...
THE REST OF THE DAY EXPECT SHOWERS MAINLY ACROSS THE SOUTHERN
SLOPES AND AFTERNOON CONVECTION OVER NORTHWESTERN PUERTO RICO.
OVERNIGHT SHOWER ACTIVITY WILL DECREASE AHEAD OF THE ESTABLISHMENT
OF A MID-UPPER LEVEL RIDGE OVER THE REGION.

THE INDUCE TROUGH ASSOCIATED TO THE SHEARLINE IS EXPECTED TO
REACH THE FORECAST AREA ON SATURDAY AFTERNOON. IN ADDITION...THE
LOCAL PRESSURE GRADIENT WILL CONTINUE WEAKENING INTO THE UPCOMING
WEEKEND DIMINISHING THE TRADE WINDS ACROSS THE REGION. GFS-12Z IS
FORECASTING NEAR CLIMATOLOGICAL PRECIPITABLE WATER VALUES...
THEREFORE...EASTERN PUERTO RICO AND U.S. VIRGIN ISLANDS CAN EXPECT
TRADE WIND SHOWERS FROM FRIDAY NIGHT INTO EARLY SATURDAY MORNING...
FOLLOWED BY POSSIBLE AFTERNOON CONVECTION OVER THE INTERIOR AND
NORTHWEST PUERTO RICO.

&&

.AVIATION...MVFR CONDITIONS WILL REMAIN POSSIBLE IN AND AROUND
JMZ AND JBQ TIL 15/22Z. AFT 15/22Z...MOSTLY VFR WITH -SHRA
POSSIBLE AT KPK AND ISX. 15 TO 20 KNOTS SE WINDS WITH SEA BREEZE
VARIATIONS...BECOMING 10 KNOTS OR LESS OVERNIGHT.

&&

.MARINE...SEAS UP TO 6 FEET AND WINDS 13 TO 19 KNOTS. SMALL BOAT
OPERATORS SHOULD EXERCISE CAUTION ACROSS MOST OF THE WATERS. WINDS
EXPECTED TO RELAX THE UPCOMING WEEKEND AND BECOMING FROM THE
NORTHEAST.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 72 86 72 / 30 20 20 20
STT 85 74 83 74 / 30 30 30 30

[cycloneye]

AFDSJU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
532 AM AST FRI JAN 16 2015

.SYNOPSIS...UPPER LEVEL SHORT WAVE TROUGH CONTINUED TO PULL FURTHER
EAST AND NORTHEAST OF THE REGION WITH THE LOCAL REGION EXPECTED TO
REMAIN ON THE SUBSIDENT SIDE OF THE UPPER TROUGH THROUGH THE FORECAST
PERIOD. SATELLITE IMAGERY STILL SHOWED PATCHES OF SHALLOW TRADE
WIND MOISTURE BEING TRANSPORTED WESTWARD ACROSS THE REGIONAL WATERS
IN THE PREVAILING SOUTHEAST TRADE WIND FLOW. IN THE LOW LEVELS...
STRONG HIGH PRESSURE CENTERED OVER THE NORTH CENTRAL ATLANTIC
WILL CONTINUE TO LIFT FARTHER NORTHEAST AS A DISSIPATING COLD
FRONT AND ASSOCIATED SHEAR LINE MOVE FARTHER EAST ACROSS THE
WEST AND SOUTHWEST ATLANTIC. AS THE FRONTAL BOUNDARY AN ASSOCIATED
SHEAR LINE APPROACH THE REGION FROM THE WEST...IT IS TO INDUCE
A WEAK SURFACE TROUGH ACROSS THE AREA BY SATURDAY AND SUNDAY.

&&

.DISCUSSION...AVAILABLE MOISTURE ALONG WITH LOCAL AND DIURNAL
EFFECTS WILL ALLOW FOR ISOLATED TO SCATTERED SHOWERS ACROSS PARTS
OF THE ISLANDS...WITH A SLIGHT CHANCE OF ISOLATED THUNDERSTORM
DEVELOPMENT IN NORTHWEST PUERTO RICO. HOWEVER LACKING UPPER LEVEL
SUPPORT...THE ACTIVITY WILL BE OF SHORT DURATION AND NOT WIDESPREAD.
LIGHT SOUTHEASTERLY WINDS ARE EXPECTED TO PREVAIL INTO THE WEEKEND...
THEN GRADUALLY SHIFT TO THE NORTHEAST AS HIGH PRESSURE BUILDS ACROSS
THE WESTERN ATLANTIC AND THE SHEAR LINE MOVES FURTHER ACROSS PUERTO
RICO AND THE VIRGIN ISLANDS BY SUNDAY. OVERALL EXPECTING LIGHT WINDS
TO PREVAIL...WITH LOCALLY AND DIURNALLY INDUCED CONVECTION MAINLY
OVER PARTS OF THE INTERIOR AND WEST SECTIONS OF PUERTO RICO. LESSER
SHOWER ACTIVITY IS EXPECTED OVER THE VIRGIN ISLANDS WITH MOSTLY
FAIR WEATHER SKIES EXPECTED TO PREVAIL AT LEAST THROUGH FRIDAY AND
INTO THE WEEKEND.

&&

.AVIATION...MOSTLY VFR CONDITIONS CAN BE EXPECTED OVER THE LOCAL
TERMINALS WITH BRIEF SHOWERS THROUGH 17/17Z...CAUSING VCSH.
AFTERNOON CONVECTION MAY CAUSE SHRA/ISOLD TSRA IN AND AROUND TJBQ
AND TJMZ AFTER 16/18Z. LOW LEVEL WINDS WILL BE MAINLY FROM THE EAST
SOUTHEAST UP TO 10 KNOTS EARLY THIS MORNING...INCREASING UP
TO 15 KNOTS AFTER 16/14Z WITH SEA BREEZE VARIATIONS DEVELOPING AS
WELL.

&&

.MARINE...SEAS UP TO 6 FEET AND WINDS 13 TO 19 KNOTS. SMALL BOAT
OPERATORS SHOULD EXERCISE CAUTION ACROSS MOST OF THE WATERS. WINDS
EXPECTED TO RELAX THE UPCOMING WEEKEND AND BECOMING FROM THE
NORTHEAST.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 85 72 85 73 / 20 20 20 30
STT 82 74 83 73 / 20 30 30 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
310 PM AST FRI JAN 16 2015

.SYNOPSIS...A MID TO UPPER LEVEL RIDGE WILL CONTINUE TO SLOWLY
BUILD OVER THE THE FORECAST AREA DURING THE WEEKEND AND HOLD THRU
THE NEXT WEEK. FRONTAL BOUNDARY OVER WESTERN ATLANTIC WILL
CONTINUE TO PUSH THE SURFACE HIGH PRESSURE EASTWARD...WEAKENING THE
SURFACE WINDS ACROSS THE LOCAL AREA. A SURFACE TROUGH INDUCED BY
THE FRONTAL BOUNDARY WILL APPROACH AREA TONIGHT THROUGH SUNDAY.

&&

.DISCUSSION...
FOR THE REST OF THE DAY...EXPECT SHOWERS MAINLY OVER THE WESTERN
INTERIOR AND WESTERN SECTIONS OF PUERTO RICO...AS WELL AS
VIEQUES...CULEBRA AND THE CARIBBEAN WATERS. OVERNIGHT...SHOWERS
EMBEDDED IN THE TRADE WINDS ARE POSSIBLE ACROSS THE WINDWARD
SECTIONS...ELSEWHERE MOSTLY CLEAR TO PARTLY CLOUDY SKIES WILL
PREVAIL. A SLIGHT INCREASE IN SHOWER POTENTIAL IS EXPECTED ON
SATURDAY AFTERNOON...WHEN A SURFACE TROUGH AND LOW LEVEL MOISTURE
NEAR TO ABOVE NORMAL VALUES ARE EXPECTED TO REACH THE AREA.
THEREFORE AFTERNOON CONVECTION AND ISOLATED THUNDERSTORMS ACROSS
THE INTERIOR AND WESTERN SECTIONS CANT BE RULED OUT ON SATURDAY.
WINDS WILL SHIFT FROM THE NORTHEAST LATE SATURDAY...BRINGING NEAR
NORMAL TEMPERATURES SUNDAY AND EARLY NEXT WEEK. NO SIGNIFICANT
CHANGES ARE EXPECT IN THE WEATHER PATTERN...THEREFORE EXPECT SMALL
AREAS OF MOISTURE EMBEDDED IN THE TRADES PROMOTING THE DEVELOPMENT
OF FEW SHOWERS OVER EASTERN SECTIONS OF PUERTO RICO DURING THE
NIGHTS AND EARLY IN THE MORNINGS EACH DAY.


&&

.AVIATION...MVFR CONDS WILL REMAIN POSSIBLE IN AND AROUND JMZ
AND JBQ TIL 16/22Z. ELSEWHERE...VFR CONDS EXPECTED THRU THE
FORECAST PERIOD. SOUTHEAST WINDS 15 KNOTS OR LESS WITH SEA
BREEZE VARIATIONS...BECOMING LIGHT AND VARIABLE TONIGHT AND
OVERNIGHT. NORTHWEST WINDS EXPECTED EARLY SATURDAY BECOMING
NORTHEAST BY LATE SATURDAY NIGHT.

&&

.MARINE...SEAS AND WINDS WILL CONTINUE TO DIMINISH ACROSS THE
LOCAL AREAS. HOWEVER THE SMALL BOAT OPERATORS SHOULD EXERCISE
CAUTION ACROSS THE ATLANTIC WATERS DUE TO SEAS UP TO 6 FEET AND
WINDS 15 KNOTS OR LESS. BEACH GOERS CAN EXPECT A LOW TO MODERATE
RISK OF RIP CURRENTS AS THE MARINE CONDITIONS IMPROVE DURING THE
WEEKEND.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 73 86 73 86 / 20 20 30 30
STT 74 83 73 83 / 30 30 40 40

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
523 AM AST SAT JAN 17 2015

.SYNOPSIS...AN UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE
NORTHEAST CARIBBEAN DURING THE WEEKEND. STRONG SURFACE HIGH PRESSURE
OVER THE NORTH CENTRAL ATLANTIC WILL CONTINUE TO LIFT FARTHER
NORTHEASTWARD AS A FRONTAL BOUNDARY AND ASSOCIATED SHEAR LINE MOVE
FARTHER EAST SOUTHEASTWARD ACROSS THE SOUTHWEST ATLANTIC. AN INDUCED
SURFACE TROUGH WILL APPROACH TO THE REGION TODAY THROUGH SUNDAY.

&&

.DISCUSSION...DOPPLER WEATHER RADAR DETECTED ONLY LIGHT ISOLATED
SHOWERS ACROSS THE SURROUNDING COASTAL WATERS OVERNIGHT AND EARLY
THIS MORNING. LIMITED SHOWER ACTIVITY...IF ANY...WAS DETECTED OVER
LAND AREAS SO FAR THIS MORNING. HOWEVER... FEW SHOWERS EMBEDDED IN
THE TRADE WINDS ARE POSSIBLE ACROSS THE WINDWARD SECTIONS OF THE
LOCAL ISLANDS DURING THE REST OF THE MORNING HOURS. ELSEWHERE ACROSS
THE REGION...CLEAR TO PARTLY CLOUDY SKIES WITH LIMITED SHOWER
ACTIVITY WILL PREVAIL. AN UPPER LEVEL RIDGE WILL CONTINUE AS THE
MAIN WEATHER FEATURE ACROSS THE REGION FOR THE NEXT FEW DAYS.
HOWEVER...A FRONTAL BOUNDARY/SHEAR LINE ACROSS THE NORTHWEST
ATLANTIC THIS MORNING...WILL PUSH A SURFACE HIGH PRESSURE ACROSS THE
CENTRAL ATLANTIC TO THE EAST NORTHEAST. THE BOUNDARY REMNANTS ARE
EXPECTED TO MEANDER ACROSS THE ATLANTIC WATERS...TO THE NORTH OF
PUERTO RICO AND THE U.S. VIRGIN ISLANDS DURING THE REST OF THE
WEEKEND. AS THIS HAPPENS AN INDUCE LOW LEVEL TROUGH IS EXPECTED TO
DEVELOP JUST ACROSS THE REGION LATE TODAY AND SUNDAY. THEREFORE
AFTERNOON CONVECTION AND POSSIBLE A COUPLE OF THUNDERSTORMS ARE
POSSIBLE ACROSS THE INTERIOR AND WESTERN SECTIONS OF PUERTO RICO
THIS AFTERNOON. THE LOCAL WINDS WILL SHIFT FROM THE NORTHEAST LATE
TODAY...BRINGING NEAR NORMAL TEMPERATURES FOR THE NEXT SEVERAL DAYS.
NO SIGNIFICANT CHANGES ARE EXPECT IN THE WEATHER PATTERN...THEREFORE
EXPECT SMALL AREAS OF MOISTURE EMBEDDED IN THE TRADES PROMOTING THE
DEVELOPMENT OF FEW SHOWERS OVER EASTERN SECTIONS OF PUERTO RICO
DURING THE NIGHTS AND EARLY IN THE MORNINGS EACH DAY.

&&

.AVIATION...MOSTLY VFR CONDS EXPECTED AT THE LOCAL TERMINALS WITH
MOSTLY CLR SKIES OVER LAND. HOWEVER TIL 17/14Z...PASSING -SHRA/SHRA
EN ROUTE MAINLY OVR OFFSHORE ATL AND CARIBBEAN WATERS. FEW-SCT CLDS
AT FL020 AND FL060 WITH ISOLD TOPS NR FL120. AFTERNOON CONVECTION
MAY CAUSE SCT SHRA/ISOLD TSRA IN AND AROUND TJMZ AND TJPS AFTER
17/17Z. EXCEPT OF LOCAL SEA BREEZE VARIATIONS...L/LVL WINDS BLO
FL100 WILL BE MAINLY FROM THE SOUTHEAST 5-10 KNOTS UNTIL 17/14Z...
THEN BCMG MORE NORTHERLY ABV FL150.

&&

.MARINE...MARINE CONDITIONS HAS IMPROVED WITH SEAS OF 5 FEET OR
LESS AND WINDS OF 14 KNOTS OR LESS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 74 85 73 / 20 30 30 30
STT 83 73 83 74 / 30 40 40 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
250 PM AST SAT JAN 17 2015

.SYNOPSIS...REMNANT COLD FRONT PASSING OVER THE ISLANDS THIS
AFTERNOON AND CAUSING SCATTERED/NUMEROUS SHOWERS OVER PUERTO RICO.
SURFACE HIGH PRESSURE IS MOVING OFFSHORE MID-ATLANTIC U.S. COAST BUT
LOOKS TOO WEAK...TOO FAR NORTH...TOO TRANSIENT TO BE ABLE TO REBUILD
TRADE WINDS HERE NEXT FEW DAYS. THE LEFT-OVER TROUGH TO HANG AROUND
UNTIL ANOTHER APPROACHING REMNANT FRONT PUSHES IT SOUTH LATE MON.

&&

.DISCUSSION...GFS SHOWS SOME 925 MB CONVERGENCE OVER PR BOTH THIS
AFTERNOON AND AGAIN MON AFTERNOON AS THE TROUGHS PASS OVER THE
ISLAND BUT THOUGH THIS RESULTED IN AREAS OF NUMEROUS SHOWERS AM
LESS CONFIDENT THAT IT WILL DO SO AGAIN MON SINCE THE PRECIPITABLE
WATER WILL BE MUCH LESS (CLOSE TO 1.3 IN. VS TODAYS 1.7). SO HIGH
CHANCE/SCATTERED NON-THUNDER CONVECTION SEEMS SUFFICIENT. THUNDER
NOT OUT OF QUESTION THIS AFTERNOON BUT INTENSITY APPEARS TO BE
PEAKING NOW WITHOUT ANY EXCEPT MAYBE OVER THE OPEN ATLANTIC ABOUT
70 NM N TO NW OF RINCON. OTHERWISE QUIET WEATHER PATTERN TO
PERSIST. TRADE WINDS BEGIN RETURN TO NORMAL ON TUE AS GFS/ECMWF/
UKMET BUILD A SURFACE RIDGE NORTH OF PR/USVI AT 25N-30N...BUT NOT
AS STRONGLY AS OCCURRED LAST COUPLE OF WEEKS.

&&

.AVIATION...MVFR/IFR CONDS POSSIBLE IN AND AROUND TJPS THRU 21Z. BKN
CLOUDS ASSOCIATED WITH A FRONTAL BOUNDARY WILL CONTINUE TO AFFECT
THE LOCAL FLYING AREA TIL LATE TONIGHT. AS A RESULT...BRIEF MVFR
CIGS POSSIBLE NEAR TJBQ AND TJSJ LATER TODAY IN PASSING SHRA. LIGHT
LLVL NORTHERLY FLOW EXPECTED THE REST OF THE WEEKEND BELOW FL100.

&&

.MARINE...SURFACE TROUGH TO REMAIN IN THE IMMEDIATE AREA THROUGH
THE WEEKEND AND WILL KEEP THE TRADE WINDS GENTLE TO MODERATE. SEAS
ALSO TO REMAIN RELATIVELY LOW WITH MINOR SWELLS COMING FROM THE
NORTH THROUGH NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 85 73 85 / 30 30 30 30
STT 73 83 74 84 / 40 40 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
458 AM AST SUN JAN 18 2015

.SYNOPSIS...UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE
NORTHEAST CARIBBEAN DURING THE REST OF WEEKEND. THIS FEATURE WILL
CONTINUE A DRY AND STABLE MID TO UPPER LEVEL AIR MASS ACROSS THE
NORTHEAST CARIBBEAN. FRONTAL BOUNDARY REMNANTS WILL CONTINUE ACROSS
THE REGION TODAY.

&&

.DISCUSSION...DOPPLER WEATHER RADAR DETECTED SCATTERED TO NUMEROUS
SHOWERS ACROSS THE NORTHEASTERN AND NORTH CENTRAL SECTIONS OF PUERTO
RICO AS WELL AS ACROSS THE COASTAL WATERS OVERNIGHT AND EARLY THIS
MORNING. THIS SHOWER ACTIVITY IS ASSOCIATED WITH THE REMNANTS OF A
FRONTAL BOUNDARY JUST OVER THE REGION. THIS MOISTURE WILL CONTINUE
TO LINGER OVER THE REGION TODAY...INDUCING THE DEVELOPMENT OF
ISOLATED TO SCATTERED SHOWERS ACROSS NORTHERN SECTIONS OF PUERTO
RICO THIS MORNING AND ACROSS THE SOUTHERN HALF OF PUERTO RICO THIS
AFTERNOON. AN UPPER LEVEL RIDGE WILL CONTINUE TO BUILD OVER THE
REGION FOR THE NEXT SEVERAL DAYS. THIS FEATURE WILL MAINTAIN A
GENERALLY DRY MID TO UPPER LEVEL AIR MASS...LIMITING THE
DEVELOPMENT OF SHOWER AND THUNDERSTORMS OVER THE REGION.
HOWEVER...A DISSIPATING FRONTAL BOUNDARY REMNANTS ACROSS THE
NORTHEAST CARIBBEAN WILL PROMOTE SOME SHOWERS ACROSS THE REGION
TODAY. THE LOCAL WINDS WILL CONTINUE FROM THE NORTHEAST...BRINGING
NEAR NORMAL TEMPERATURES FOR THE NEXT SEVERAL DAYS. TRADE WINDS
BEGIN RETURN TO NORMAL ON TUESDAY AS A SURFACE HIGH PRESSURE
DEVELOPS TO THE NORTH OF PUERTO RICO AND THE U.S. VIRGIN ISLANDS.
NO SIGNIFICANT WEATHER FEATURE IS EXPECTED TO AFFECT THE REGION FOR
THE NEXT SEVERAL DAYS.

&&

.AVIATION...BKN-OVC CLD LYRS BTW FL020-150 ASSOCIATED WITH A FRONTAL
BOUNDARY NOW ACROSS THE NE CARIBBEAN AND WILL CONTINUE TO AFFECT PR
AND THE NRN LEEWARDS TIL AT LEAST 18/15Z...BCMG SCT-BKN THEREAFTER.
ISOLD-SCT EMBEDDED -SHRA/SHRA ASSOC W/FRONTAL BNDRY WITH BRIEF MVFR
CONDS DUE TO LOW CLDS AND SHRA EN ROUTE BTW LOCAL ISLANDS. MSTLY SCT
CLDS LYRS OVR TNCM/TKPK. VFR CONDS SHOULD PREVAIL ACROSS MOST TAF
SITE HOWEVER EXCEPT FOR THE BRIEF MVFR CIGS...MAX TOPS AROUND 150.
THE 18/00Z TJSJ SOUNDING INDICATED NW-N WINDS BLO FL100 AT 12 KT
OR LESS...AND 20-28 KTS BTWN FL150-200.

&&

.MARINE...QUIET MARINE CONDITIONS WILL REMAINS FOR THE NEXT FEW
DAYS WITH SEAS OF 2 TO 5 FEET AND WINDS UP TO 14 KNOTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 73 84 73 / 30 30 30 30
STT 83 73 82 73 / 40 30 30 40