Caribbean - Central America Weather

[cycloneye]

If the trough is just east of the Leeward Islands as it deepens,then will it be still producing rain in the Leeward Islands on Saturday?
Does It seems that the trough is going to move much faster than first forecasted?And it looks like instead of the bulk of moisture missing to the south of PR and the VI,it looks like the forecast is bringing it further north once again,correct?

First answer is some scattered showers.

Second answer is maybe.

Third answer is looking like that right now.

Fourth answer is not known yet.

[Gustywind]

If the trough is just east of the Leeward Islands as it deepens,then will it be still producing rain in the Leeward Islands on Saturday?
Does It seems that the trough is going to move much faster than first forecasted?And it looks like instead of the bulk of moisture missing to the south of PR and the VI,it looks like the forecast is bringing it further north once again,correct?

First answer is some scattered showers.

Second answer is maybe.

Third answer is looking like that right now.

Fourth answer is not known yet.

Fifth answer is to wait and see

Sixth answer is stay tuned

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
501 AM AST THU DEC 4 2014

.SYNOPSIS...AT MID AND UPPER LEVELS...AS THE RIDGE OF PREVIOUS
DAYS MOVES OVER THE LEEWARD ISLANDS A TROUGH AND ACCOMPANYING
JET STREAM WILL APPROACH THE AREA FOR A PASSAGE ON FRIDAY NIGHT.
RIPPLES IN THE WEST NORTHWEST FLOW THAT FOLLOWS WILL THEN CONTINUE
THROUGH MUCH OF NEXT WEEK. MID AND UPPER LEVELS ARE BECOMING MORE
MOIST...BUT WILL DRY OUT BEGINNING ON SATURDAY. THESE LEVELS
REMAIN DRY THROUGH NEXT WEEK.

AT LOWER LEVELS...A TROUGH FORMING ALONG 60 WEST IN THE WESTERN
TROPICAL ATLANTIC WILL EXTEND TO THE NORTH ON FRIDAY AND SATURDAY AND
FORM A DEEPENING LOW. THIS WILL CAUSE FLOW TO BECOME MORE
NORTHERLY...DISRUPTING THE TRADE WINDS AND BRING DOWN COOLER AIR
FROM THE NORTH. SHALLOW MOISTURE WILL CONTINUE THROUGH THE
FORECAST PERIOD.

&&

.DISCUSSION...SHOWERS FORMED IN THE WAKE AROUND PUERTO RICO AND
THE U.S. VIRGIN ISLANDS WITH SOME SHOWERS COMING IN OVER EASTERN
PUERTO RICO. PRECIPITABLE WATER FROM LAST NIGHT`S 00Z SOUNDING
CAME IN AT 1.93 INCHES AND WAS PRESENT THROUGH 9 KFT. MOISTURE IS
FORECAST TO CONTINUE THROUGH FRIDAY MAKING SHOWERS LIKELY OVER
MOST OF PUERTO RICO AND KEEPING AT LEAST A CHANCE OF SHOWERS OVER
THE U.S. VIRGIN ISLANDS THROUGH FRIDAY. AN APPROACHING TROUGH WILL
ALSO KEEP A SLIGHT CHANCE FOR A THUNDERSTORM IN THE FORECAST.
SINCE SHALLOW MOISTURE CONTINUES THROUGH MUCH OF THE NEXT
WEEK...EVEN AFTER DEEPER MOISTURE LEAVES THE AREA...BRIEF PASSING
SHOWERS...AS IS SO TYPICAL OF DECEMBER IN PUERTO RICO AND THE U.S.
VIRGIN ISLANDS...WILL CONTINUE IN THEIR TYPICAL DIURNAL PATTERN OF
EARLY MORNING SHOWERS ON THE WINDWARD COASTS AND AFTERNOON SHOWERS
WITH A SLIGHT CHANCE OF A THUNDERSTORM IN THE WESTERN INTERIOR.
WINDS WILL DIMINISH IN THE LOWEST 5000 FEET OF THE ATMOSPHERE
THROUGH SUNDAY AS THE DEEPENING LOW PRESSURE TO OUR NORTH
NORTHEAST ALLOWS PRESSURE GRADIENTS IN PLACE FROM THE PERSISTENT
HIGH PRESSURE TO RELAX. THIS WILL ALLOW FOR SOMEWHAT HIGHER RAIN
AMOUNTS. THE NEXT SEVERAL DAYS WILL PROVIDE OPPORTUNITY FOR ENOUGH
RAIN TO FALL TO JUSTIFY URBAN AND SMALL STREAM FLOODING BUT THESE
CONDITIONS WILL NOT BE WIDESPREAD ACROSS THE AREA AND WILL LIKELY
NOT OCCUR IN THE U.S. VIRGIN ISLANDS. COOL AIR ADVECTION IS
OCCURRING IN THE LOWEST 10 KFT AND IS EXPECTED TO USHER IN SLIGHTLY
COOLER TEMPERATURES OVER THE WEEKEND AND INTO NEXT WEEK.

&&

.AVIATION...MAINLY VFR CONDS EXPECTED THROUGH THE FORECAST PERIOD.
TRADE WIND SHOWERS WILL CONTINUE TO MOVE IN AND AROUND THE LEEWARD
ISLANDS...USVI AND EASTERN PR TERMINALS. CREATING BRIEF MVFR CIGS
AND VCSH. FOLLOWED BY AFTERNOON CONVECTION OVER THE INTERIOR AND SW
PR MOUNTAIN CREATING MOUNTAIN OBSCURATION AND SHRA/TSRA POSSIBLE AT
TJMZ/TJPS. WINDS WILL CONTINUE FM THE EAST-NORTHEAST AT 10-15 KT
WITH HIGHER GUSTS AND SEA BREEZE VARIATIONS AFT 04/14Z.


&&

.MARINE...SWELL IS SLOWLY DIMINISHING AND SEAS WILL CONTINUE TO
SUBSIDE AS WINDS WEAKEN EVEN MORE OVER THE WEEKEND. SEAS WILL FALL
ONLY TO AROUND 6 FEET IN THE OUTER ATLANTIC WATERS THROUGH
THURSDAY. SEAS MAY ALSO RISE AGAIN IF THE LOW PRESSURE TO DEVELOP TO
THE NORTH NORTHEAST BECOMES ANY STRONGER THAN THE CURRENT MODEL
RUNS ARE SUGGESTING. HENCE SMALL CRAFT ADVISORIES IN THE NORTHERN
OUTER ATLANTIC WATERS CANNOT BE RULED OUT EARLY NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 76 83 76 / 70 60 60 50
STT 86 76 85 76 / 50 60 50 50

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
314 PM AST THU DEC 4 2014

.SYNOPSIS...UPPER LEVEL TROUGH APPROACHING FROM THE WEST IS
DESTABILIZING THE ATMOSPHERE ACROSS THE ISLANDS. THE AXIS OF THE
UPPER TROUGH IS FORECAST TO CROSS THE LOCAL AREA ON FRIDAY.
THEREFORE...MOISTURE AND INSTABILITY WILL INCREASE AS THE TROUGH
MOVES EASTWARD ACROSS THE REGION OVER THE NEXT 24 HOUR...RESULTING
IN SCATTERED TO NUMEROUS SHOWERS ACROSS THE ISLANDS. WEATHER CONDITIONS
WILL IMPROVE DURING THE WEEKEND AS A SUBSIDENCE PATTERN ESTABLISHES
ACROSS THE FORECAST AREA IN RESPONSE TO THE AMPLIFICATION OF THE
UPPER TROUGH EAST OF THE LEEWARD ISLANDS.

&&

.DISCUSSION...A SHEARLINE OVER THE NORTHEAST CARIBBEAN REGION HAVE
INDUCED LOW LEVEL CONVERGENCE ACROSS THE LOCAL ISLANDS TODAY. THIS
CONVERGENCE RESULTED IN PERSISTENT SHOWERS ACROSS NORTHEAST PR...
ESPECIALLY EL YUNQUE AREA WHERE RADAR ESTIMATES UP TO ONE INCH OF
RAINFALL EARLY THIS AFTERNOON. THEN...SCATTERED TO NUMEROUS SHOWERS
DEVELOPED ACROSS MOST OF PUERTO RICO...WITH THE MOST INTENSE
SHOWERS OBSERVED ACROSS WEST AND SOUTH PR. AFTERNOON CONVECTION
WILL CONTINUE TO AFFECT PORTIONS OF PR AND USVI THIS AFTERNOON...
ESPECIALLY ACROSS THE SOUTH AND SOUTHWEST PR. MODEL GUIDANCE
SUGGESTS ANOTHER ROUND OF SHOWERS TONIGHT AND OVERNIGHT ACROSS THE
CARIBBEAN WATERS NEAR ST. CROIX...AS WELL AS THE NORTH AND EAST
PR. DIVERGENCE ALOFT ASSOCIATED WITH THE UPPER TROUGH COULD ALSO
ENHANCE THE NOCTURNAL CONVECTION RESULTING IN ISOLATED TO SCATTERED
THUNDERSTORMS. UNSTABLE CONDITIONS WILL CONTINUE THROUGH AT LEAST
LATE FRIDAY AFTERNOON.

DURING THE WEEKEND AND EARLY NEXT WEEK...A SUBSIDENCE PATTERN WILL
ESTABLISH ACROSS THE NORTHEAST CARIBBEAN REGION AS THE UPPER TROUGH
MOVE EASTWARD INTO THE TROPICAL ATLANTIC. THE UPPER TROUGH IS FORECAST
TO AMPLIFY EAST OF THE LEEWARD ISLANDS...RESULTING IN UPPER LEVEL
CONVERGENCE AND SUBSIDENCE PATTERN ACROSS PUERTO RICO AND USVI. AS
A RESULT...MID-UPPER LEVEL MOISTURE WILL DIMINISH SIGNIFICANTLY...
LIMITING THE DEEP CONVECTION ACROSS THE ISLANDS. AT LOW LEVELS...A
LONG FETCH NORTHERLY FLOW WILL ESTABLISH ACROSS THE REGION. THE
NORTHERLY FLOW WILL FAVOR LIGHT SHOWERS AFFECTING THE NORTHERN
PORTIONS OF THE ISLANDS AT NIGHT AND EARLY IN THE MORNING. BECAUSE
MOISTURE WILL BE CONFINED IN THE LOWER ATMOSPHERE...BELOW 800
MB...NO SIGNIFICANT RAINFALL ACCUMULATIONS ARE EXPECTED OVER THE
WEEKEND AND EARLY NEXT WEEK.

&&

.AVIATION...AFTERNOON CONVECTION OVER WEST AND SOUTH PR COULD
PRODUCE BRIEF PERIOD OF MVFR/IFR CONDS AN MOUNTAIN OBSCURATIONS IN
AND AROUND TJMZ AND TJPS. THEN SHOWERS LIKELY AT JSJ...USVI TERMINALS
AT NIGHT WITH MVFR CONDITIONS. LLVL WINDS OF 5-15 KT WILL GRADUALLY
SHIFT TO THE NORTH OVER THE NEXT 24 HRS.

&&

.MARINE...SEAS ARE BEGINNING TO DIMINISH AT BUOY 41043 AND NEARSHORE
BUOYS. THIS DOWNTREND EXPECTED TO CONTINUE THROUGH SATURDAY. SFC WINDS
ALSO EXPECTED TO DIMINISH THROUGH THE WEEKEND. ANOTHER NE PULSE WILL
BE ARRIVING ON SUNDAY BUT IT WILL QUICKLY SUBSIDE THROUGH MONDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 83 76 83 / 60 60 50 50
STT 76 85 76 85 / 40 40 50 50

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
404 AM AST FRI DEC 5 2014

.SYNOPSIS...AN UPPER LEVEL TROUGH NORTH AND WEST OF THE REGION
WILL MAINTAIN RELATIVELY UNSTABLE WEATHER CONDITIONS ACROSS THE
LOCAL ISLANDS TODAY. THE TROUGH WILL MOVE RAPIDLY TO THE EAST OF
THE REGION TONIGHT AND SATURDAY IN AN UNFAVORABLE POSITION FOR
SHOWERS AND THUNDERSTORMS. THUS...WEATHER CONDITIONS WILL IMPROVE
TONIGHT AND DURING THE REST OF THE WEEKEND AS A SUBSIDENCE PATTERN
ESTABLISHES ACROSS THE FORECAST AREA IN RESPONSE TO THE
AMPLIFICATION OF THE UPPER TROUGH EAST OF THE LEEWARD ISLANDS.

&&

.DISCUSSION...DURING THE WEEKEND AND EARLY NEXT WEEK...A SUBSIDENCE
PATTERN WILL ESTABLISH ACROSS THE NORTHEAST CARIBBEAN REGION AS
THE UPPER TROUGH MOVE EASTWARD INTO THE TROPICAL ATLANTIC. THE
UPPER TROUGH IS FORECAST TO AMPLIFY EAST OF THE LEEWARD
ISLANDS...RESULTING IN UPPER LEVEL CONVERGENCE AND SUBSIDENCE
PATTERN ACROSS PUERTO RICO AND USVI. AS A RESULT...MID-UPPER LEVEL
MOISTURE WILL DIMINISH SIGNIFICANTLY...LIMITING THE DEEP
CONVECTION ACROSS THE ISLANDS.

A NORTHERLY WIND FLOW WILL ESTABLISH ACROSS THE REGION TONIGHT. THIS
NORTHERLY FLOW WILL FAVOR LIGHT SHOWERS ACROSS THE NORTHERN AND
EASTERN SECTIONS OF PUERTO RICO AT NIGHT AND EARLY IN THE MORNING.
BECAUSE MOISTURE WILL BE CONFINED IN THE LOWER ATMOSPHERE...BELOW
800 MB...NO SIGNIFICANT RAINFALL ACCUMULATIONS ARE EXPECTED OVER THE
WEEKEND AND EARLY NEXT WEEK.

&&

.AVIATION...A LOW PRES IS EXPECTED TO DVLP N OF PR CAUSING WINDS TO
WEAKEN AND BCM NLY. MOIST AIR BRINGING SHRA TO AREA FOR BRIEF MVFR
CIGS TNCM AND TKPK AND MTN OBSCURATIONS IN PR. CLRG EXPECTED AFT
05/18Z WITH ISOLD SHRA N COAST PR AND OVER WATERS. LLVL WINDS NE 5
TO 15 KT BCMG AFT 05/15Z N 5 TO 12 KT. WINDS ABV 16 KFT W INCRG TO
70 TO 80 KT 40 TO 46 KFT.

&&

.MARINE...SMALL CRAFTS SHOULD CONTINUE TO EXERCISE CAUTION ACROSS
MUCH OF THE LOCAL WATERS. BUOYS ACROSS THE NEAR SHORE ATLANTIC
WATERS ARE INDICATING SEAS OF 4-6 FEET. ANOTHER NE PULSE WILL BE
ARRIVING ON SUNDAY BUT IT WILL QUICKLY SUBSIDE THROUGH MONDAY.
WINDS OVER THE WATERS WILL BE MAINLY FROM THE NORTH TO NORTHEAST
BETWEEN 7 TO 15 KNOTS DURING THE OVERNIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 76 83 76 / 40 40 40 40
STT 85 76 85 76 / 40 30 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
302 PM AST FRI DEC 5 2014

.SYNOPSIS...BROAD TROUGH OVR THE WRN ATLC WILL MAINTAIN COOLER
THAN NORMAL TEMPERATURES THROUGH WED MORNING. FLAT RIDGE WILL
BUILD MID TO LATE NEXT WEEK WITH TEMPS REBOUNDING BACK TO NORMAL.

&&

.DISCUSSION...DEEPENING UPPER LOW NORTH OF THE AREA WILL SHIFT
EAST OF THE AREA TONIGHT WITH ASSOCIATED JET STREAK SHIFTING
SOUTH OF THE AREA BY 12Z SAT PUTTING LOCAL AREA UNDER ITS UPPER
LEVEL CONVERGENT SIDE LEADING TO STRENGTHENING OF THE SUBSIDENCE
INVERSION AND DRYING THROUGH EARLY NEXT WEEK. BELOW NORMAL HEIGHTS
OVER THE NEXT SVRL DAYS...MOSTLY CLEAR SKIES AND DRY AIR WILL
RESULT IN COOLER THAN NORMAL TEMPERATURES INTO MID NEXT WEEK.

AFTER WED...MODELS SHOW DEEP TROUGH PATTERN OVER EASTERN NORTH
AMERICA WEAKENING AND LIFTING NORTHEAST INTO THE CANADIAN
MARITIMES WITH OVERALL HEIGHT RISES OVR THE NORTHEAST CARIBBEAN.
THIS WILL RESULT IN TEMPERATURES TRENDING MORE BACK TO NORMAL
TOWARD THE END OF NEXT WEEK. PRES GRADIENT WILL REMAIN RELATIVELY
WEAK WITH NO MOISTURE ADVECTION EXPECTED DURING THE NEXT SEVEN
DAYS. OVERALL...VERY QUIET AND DRY WX PATTERN EXPECTED NEXT SEVEN
DAYS.

&&

.AVIATION...VFR CONDITIONS NEXT FIVE DAYS WITH NO SIG WX.

&&

.MARINE...WINDS 10 KT OR LESS. NE SWELLS WILL SLOWLY SUBSIDE
THROUGH SUN MORNING WITH ANOTHER PULSE EXPECTED SUN AFTERNOON INTO
MONDAY AFTERNOON.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 83 76 83 / 20 20 20 10
STT 76 85 76 84 / 10 20 20 10

[cycloneye]

Pardon the inconvencience for being late as I was without internet this morning.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
518 AM AST SAT DEC 6 2014

.SYNOPSIS...AT UPPER LEVELS...AN 85 KNOT JET CROSSED OVER THE AREA
LAST NIGHT AND A WEAK TROUGH WILL FOLLOW IT EARLY THIS MORNING.
NEVERTHELESS LITTLE DYNAMICS ARE SEEN WITH THESE FEATURES. A WEAK
TROUGH WILL ALSO PASS THROUGH THE AREA SUNDAY AFTERNOON. WEST
NORTHWEST FLOW WILL CONTINUE THROUGH MID WEEK AND WINDS WILL PICK
UP AS A SLIGHTLY ANTI CYCLONIC JET MOVES OVER THE AREA FROM THE
SOUTH MID WEEK NEXT WEEK. FLOW WILL TURN SLIGHTLY SOUTHWEST UNDER
THIS JET BY THURSDAY.

AT MID LEVELS...LOW PRESSURE NORTHEAST OF SAN JUAN AT 60 WEST WILL
DEEPEN SLIGHTLY OVER THE WEEKEND BEFORE BEING ABSORBED INTO A LONG
WAVE TROUGH SUNDAY. GRADIENTS WILL WEAKEN IN THE NORTHWEST FLOW
OVER THE AREA AFTER A MID-LATITUDE SHORT WAVE TROUGH PASSES BY ON
MONDAY FOLLOWED BY A SHIFT TO SOUTHWEST FLOW AS A LARGE LOW
ROTATES THROUGH THE NORTHEASTERN UNITED STATES. AFTER WHICH HIGH
PRESSURE WILL DOMINATE THE CARIBBEAN THROUGH THE END OF NEXT WEEK
UNTIL A SECOND LARGE LOW PRESSURE MOVES INTO THE WESTERN ATLANTIC
SATURDAY OF NEXT WEEK. MID LEVELS WILL BE MOSTLY DRY THROUGH THE
NEXT 10 DAYS.

AT LOWER LEVELS...A WEAK INVERTED TROUGH WILL DEEPEN THROUGH
SATURDAY NIGHT BEFORE MOVING NORTHEAST EARLY NEXT WEEK. FLOW
BECOMES EASTERLY NEXT WEEK AS VERY WEAK HIGH PRESSURE SETTLES JUST
NORTH OF THE AREA MID WEEK AND FLOW PERSISTS FROM THE CENTRAL
ATLANTIC.

&&

.DISCUSSION...SMALL SHOWERS PAINTED LIGHT TRAILS OVERNIGHT OF THE
MOST MINIMAL MEASURABLE RAINFALL AMOUNTS IN NORTHERLY FLOW
GENERATED BY THE LOW FORMING 640 MILES NORTHEAST OF PUNTA CANA IN
THE DOMINICAN REPUBLIC. SHOWERS COVERED ABOUT 10 TO 20 PERCENT OF
THE NORTHERN QUARTER OF PUERTO RICO AND THE NORTHERN U.S. VIRGIN
ISLANDS. THE GFS CONTINUES TO BE MUCH DRIER THAN PREVIOUS RUNS AND
ALMOST ANY PREVIOUS PERIOD THIS YEAR WITH PRECIPITABLE WATER
VALUES FALLING BELOW 0.90 INCHES ON BOTH MONDAY NIGHT AND EARLY
WEDNESDAY MORNING. ALSO NOTE THAT LITTLE OR NO DIVERGENCE OCCURS
AT THE 250 MB LEVEL AND SOME DOWNWARD MOTION IS ALSO
INDICATED...THEREFORE...HAVE LOWERED POPS OVER MANY AREAS DURING
THIS PERIOD AND DURING THE WEAK RECOVERY OF THURSDAY AND FRIDAY
MORNING. EVEN DURING A SUPPOSEDLY WET PERIOD FORECAST FOR THE
SUNDAY AFTER NEXT THE GFS ONLY HAS PRECIPITABLE WATER VALUES
REACHING 1.7 INCHES. IN COMPARISON WITH THE SOUNDERS AND THE LAST
RADIOSONDE AT 06/00Z MODEL VALUES ARE ABOUT .15-.25 INCHES TOO
LOW... BUT EVEN THIS MAY NOT BE ENOUGH TO CREATE MORE THAN A 10 TO
20 PERCENT CHANCE OF SHOWERS OVER THE WEEKEND AND THE FIRST PART
OF NEXT WEEK. WITH THE CURRENT SEVERE DRY BIAS OF THE GFS TOWARD
THE LATTER END OF ITS FORECAST THE LAST SEVERAL MONTHS... AND NO
VALUES EXCEEDING 19 PERCENT IN THE MEXJSJ THIS WEEK I MUST ALSO
NOTE THAT CONFIDENCE OF SO FEW SHOWERS FOR THIS WEEK IN DECEMBER
IS ONLY MEDIUM. HOWEVER EXPECT BETTER SHOWER ACTIVITY LATE NEXT
WEEK INTO THE WEEKEND AS MOISTURE COMES IN FROM THE CENTRAL
ATLANTIC.

&&

.AVIATION...VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS. ONLY
-SHRA EMBEDDED ON NORTHERLY FLOW OVER THE ATLANTIC WATERS COULD
REACH PARTS OF THE NORTHERN TERMINALS OF PR AND THE USVI. THE 06/00Z
TJSJ UPPER AIR SOUNDING INDICATED LOW LEVEL N-NW WINDS AT 4-12
KT...BCMG NW-W AT FL150 AND ABOVE WITH 20-30 KT AND HIGHER WINDS.

&&

.MARINE...MULTIPLE VIGOROUS HIGHS AND LOWS TRANSITING THE
ATLANTIC WILL KEEP SEAS FAIRLY AGITATED WITH SWELL GROUPS COMING
IN FROM THE NORTH NORTHWEST AND THE NORTHEAST MONDAY THROUGH THURSDAY.
THEREFORE AM KEEPING THE 7 FOOT SEAS IN THE NORTHERN ATLANTIC
WATERS. SPECTRAL MODEL SUGGESTS SEAS UP TO 10 FEET BEGINNING
WEDNESDAY. WILL UPDATE FORECAST WHEN WAVE GENERATION CAN BE
CONFIRMED SINCE THERE IS SOME UNCERTAINTY WITH REGARD TO WIND
STRENGTH IN THE CRITICAL FETCH AREAS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 85 76 83 74 / 20 20 0 10
STT 86 76 84 77 / 20 20 10 10

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
306 PM AST SAT DEC 6 2014

.SYNOPSIS...DEEP LAYERED AREA OF LOW PRESSURE AND ASSOCIATED TROUGH
LOCATED ACROSS THE WEST CENTRAL ATLANTIC WILL MAINTAIN AN OVERALL
NORTHERLY WIND FLOW ACROSS THE REGION AT LEAST THROUGH SUNDAY. THIS
WILL PROMOTE FAIRLY COOL AND STABLE ATMOSPHERE ACROSS THE REGION
DURING THE REMAINDER OF THE WEEKEND. WINDS ALOFT ARE FORECAST TO
BECOME MORE ZONAL/WESTERLY LATE SUNDAY INTO EARLY NEXT WEEK AS SHORT
WAVE TROUGH MOVES ACROSS THE NORTHWEST ATLANTIC AND NORTH OF THE
FORECAST AREA. MEANWHILE...SURFACE TROUGH ACROSS THE ATLANTIC WILL
MAINTAIN THE PREVAILING LIGHT TO MODERATE NORTH NORTHEAST LOW LEVEL
WIND FLOW OVER THE NEXT FEW DAYS.

&&

.DISCUSSION...PREVAILING STEERING LOW LEVEL WINDS WILL CONTINUE
TO PROMOTE OVERALL FAIR WEATHER SKIES WITH FEW PASSING SHOWERS AND
SHALLOW LOW LEVEL CLOUDS MOVING ACROSS THE REGION. THE SHOWERS WILL
BE MOSTLY LIGHT AND SHOULD AFFECT MAINLY PARTS OF THE NORTHERN HALF
OF THE ISLANDS ESPECIALLY DURING THE OVERNIGHT AND EARLY MORNING
HOURS. THIS WILL BE FOLLOWED BY A GRADUAL CLEARING AND MOSTLY FAIR
WEATHER SKIES DURING THE AFTERNOON HOURS. FEW LIGHT TO MODERATE
SHOWERS WILL REMAIN POSSIBLE EACH DAY. NO MAJOR CHANGES DURING THE
EARLY PART OF NEXT WEEK...HOWEVER THE LOW LEVEL STEERING FLOW
SHOULD BECOME MORE EASTERLY BY MONDAY AND TUESDAY AS A WEAK AREA
OF HIGH PRESSURE IS FORECAST TO SETTLE JUST NORTH OF THE REGION.
STILL HOWEVER NO SIGNIFICANT MOISTURE ADVECTION IN SIGHT AT THIS
TIME EXCEPT FOR FRAGMENTS OF SHALLOW TRADE WIND MOISTURE WHICH
WILL MOVE ACROSS THE REGION FROM TIME TO TIME...FOLLOW BY MOSTLY
LIGHT AFTERNOON CONVECTION EACH AFTERNOON WITH MOSTLY FAIR WEATHER
SKIES FORECAST TO PREVAIL.

&&

.AVIATION...VFR CONDS EXPECTED THROUGH THE NEXT 24 HOURS WITH ONLY
PASSING -SHRA. WINDS AT TJBQ AND TJMZ FROM THE EAST TO ENE BUT
ELSEWHERE MAINLY FROM THE NORTH AT 5 TO 15 KTS AT THE SFC UNTIL
06/22Z...DECREASING AND BECOMING VARIABLE OVERNIGHT. NO SIGNIFICANT
WEATHER HAZARDS EXPECTED.


&&

.MARINE...SEAS UP TO 6 FEET MAINLY ACROSS THE LOCAL ATLANTIC WATERS
WITH A SLOWLY FADING NORTHEASTERLY SWELL CONTINUING TO AFFECT PARTS
OF THE LOCAL WATERS AND PASSAGES. PLEASE REFER TO THE LATEST COASTAL
WATERS FORECAST ISSUED BY THE NATIONAL WEATHER SERVICE WFO SAN JUAN.
SMALL CRAFT SHOULD EXERCISE CAUTION ACROSS THE OFFSHORE ATLANTIC WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 83 71 81 / 20 20 10 10
STT 74 84 72 85 / 20 20 10 10

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
409 AM AST SUN DEC 7 2014

.SYNOPSIS...AT UPPER LEVELS...WEST NORTHWEST FLOW WILL CONTINUE
INTO EARLY THIS WEEK. THE JET STREAM THAT CROSSED THROUGH PUERTO
RICO OVERNIGHT YESTERDAY WILL RETURN TO THE AREA LATE MONDAY INTO
TUESDAY. FLOW WILL SHIFT MORE TO THE WEST SOUTHWEST AS THE RIDGE
CROSSES THROUGH TUESDAY NIGHT FOLLOWED BY A WEAK TROUGH ON
THURSDAY MORNING. DYNAMICS ARE WEAK AND FLOW AT UPPER LEVELS IS
OFTEN CONVERGENT.

AT MID LEVELS...LOW PRESSURE ALONG 60 WEST WILL MERGE WITH THE
UPPER LEVELS FLOW TONIGHT AND HIGH PRESSURE WILL RETURN TO THE
CARIBBEAN WATERS TUESDAY AND WEDNESDAY. A STRONG UPPER LEVEL
TROUGH WILL MOVE THROUGH THE WESTERN ATLANTIC WEDNESDAY NIGHT BUT
WILL RESULT IN A RIDGE EXTENDING NORTHEAST OF THE AREA. HIGH
PRESSURE DOMINATES THE CARIBBEAN FRIDAY THROUGH SUNDAY OF THIS WEEK.
A STRONG TROUGH MAY COME THROUGH MID MONTH.

AT LOWER LEVELS...LOW PRESSURE ALONG 60 WEST WILL MOVE NORTHEAST
SOMEWHAT AND THEN BE ABSORBED BY A LOW THAT DEEPENS TO ITS WEST
AND MOVES INTO THE NORTHEAST UNITED STATES WEDNESDAY. THIS WILL
LEAVE WEAK GRADIENTS AND LIGHT WINDS OVER THE LOCAL AREA THROUGH
THURSDAY AND LIGHT TO MODERATE TRADE WIND FLOW THROUGH MID MONTH.

&&

.DISCUSSION...SHOWERS CAME ONSHORE IN PUERTO RICO AND QUICKLY
DISSIPATED LEAVING VERY LIGHT AMOUNTS ALONG THE NORTHERN
COAST...MAINLY FROM ARECIBO EAST. SHOWERS WERE HEAVIER OVER THE
WATERS NORTH OF CULEBRA AND THE NORTHERN VIRGIN ISLANDS. SOME
SHOWERS WERE ALSO SEEN IN AND BEYOND OUR SOUTHERNMOST LOCAL OUTER
CARIBBEAN WATERS. THE GFS SHOWS PRECIPITABLE WATER DECREASING
THROUGHOUT THE DAY TODAY AND BOUNCING LATE SUNDAY NIGHT AND DURING
THE DAY MONDAY TO LEVELS SEEN YESTERDAY. A FEW BANDS OF MOISTURE
MAY ROLL AROUND THE LOW PRESSURE IN THE NORTHERLY FLOW OVER THE
AREA MONDAY AND TUESDAY AND ISOLATED SHOWERS CANNOT BE RULED OUT
OVER THE INTERIOR MONTANE AREAS OF PUERTO RICO EACH AFTERNOON.
THE GFS IS NOW SHOWING FLOW BECOMING MORE EASTERLY ON MONDAY AND
MONDAY NIGHT...PROBABLY DUE TO THE FACT THAT THE LOW PRESSURE
ALONG 60 WEST DID NOT DEEPEN AS MUCH AS THE MODEL HAD ORIGINALLY
FORECAST. THIS WILL INCREASE THE PROBABILITIES OF NIGHT AND EARLY
MORNING SHOWERS IN EASTERN PUERTO RICO EVER SO SLIGHTLY EACH NIGHT
MONDAY THROUGH THURSDAY. THEN BETTER MOISTURE ARRIVES AND IT IS
EXPECTED WE WILL SEE SCATTERED SHOWERS ON THE WINDWARD COASTS AND
IN THE U.S. VIRGIN ISLANDS FRIDAY NIGHT AND INTO THE WEEKEND.

THE LONG TERM OUTLOOK CURRENTLY SEES A COLD FRONT MOVING THROUGH
ON MONDAY...15 DECEMBER...JUST AS IT DISSIPATES. THIS SHOULD BRING
COOL-WEATHER SHOWERS BACK. AMOUNTS WILL BE LIGHT FOR THOSE THAT
RECEIVE SHOWERS. THE NORTHEASTERLY FLOW THEN WILL LEAVE SOUTHERN
PUERTO RICO MOSTLY SHELTERED AND WARM HOWEVER.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS
WITH ONLY PASSING -SHRA. LATEST TJSJ SOUNDING INDICATED A LIGHT
NORTHERLY WIND FLOW ALL THE WAY FROM THE SURFACE TO AROUND 15K
FEET...BECOMING NORTHWESTERLY AND STRONGER ABOVE 15K FEET. NO
SIGNIFICANT WEATHER HAZARDS EXPECTED.


&&

.MARINE...WHILE SEAS REMAIN ABOVE 7 FEET AT THE OUTER BUOY
41043...SEAS REMAIN 5 TO 6 FEET IN LOCAL INNER ATLANTIC WATERS.
SEAS WILL INCREASE MID WEEK THIS WEEK AND SMALL CRAFT ADVISORIES
WILL LIKELY BE RAISED. MODELS ARE INDICATING SEAS MAY RISE EVEN TO
8 FEET...BUT WILL HOLD OFF IN CASE MODELS ARE OVER FORECASTING
STORMINESS IN THE ATLANTIC AS THEY DID THIS WEEKEND. CARIBBEAN
SEAS WILL REMAIN TRANQUIL THROUGH AT LEAST LATE IN THE WEEK. SMALL
CRAFT ADVISORIES ARE NOT EXPECTED IN THE CARIBBEAN THROUGH BEYOND
MID MONTH.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 75 83 76 / 20 0 10 20
STT 84 78 86 79 / 20 10 10 10

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
253 PM AST SUN DEC 7 2014

.SYNOPSIS...MID TO UPPER LEVEL AREA OF LOW PRESSURE AND ASSOCIATED
TROUGH ACROSS THE WEST CENTRAL ATLANTIC SLOWLY LIFTING FURTHER NORTH
OF THE AREA...WILL MAINTAIN AN WEST TO NORTHWEST WIND FLOW OVERNIGHT
THROUGH MONDAY...TO MAINTAIN SUBSIDENT AND STABLE AIR MASS ALOFT.
WINDS ALOFT ARE FORECAST TO BECOME MORE ZONAL/WESTERLY LATER MONDAY
AND DURING THE EARLY PART OF THE UPCOMING WEEK AS SHORT WAVE TROUGH
MOVES ACROSS THE NORTHWEST ATLANTIC AND NORTH OF THE FORECAST AREA.
LOW LEVEL TROUGH ACROSS THE WEST CENTRAL ATLANTIC WILL MAINTAIN A
LIGHT NORTH NORTHEAST LOW LEVEL WIND FLOW AT LEAST THROUGH MONDAY
BUT WINDS ARE STILL FORECAST TO BECOME MORE EASTERLY BY LATE TUESDAY
AND REMAINDER OF THE WEEK...AS SURFACE HIGH PRESSURE WEAKLY ESTABLISHES
NORTH OF THE FORECAST AREA.

&&

.DISCUSSION...FAIR WEATHER SKIES AND PLEASANT TEMPERATURES PREVAILED
ACROSS THE REGION TODAY WITH NO PRECIPITATION OBSERVED ACROSS THE
ISLANDS. RECENT SATELLITE IMAGERY AND DOPPLER WEATHER RADAR...AS
WELL AS SATELLITE DERIVED PRECIPITABLE WATER PRODUCTS...ALL SHOWED
DRY AND STABLE CONDITIONS PREVAILING WITH PRECIPITABLE WATER VALUES
DOWN TO LESS THAN ONE INCH ACROSS THE REGION TODAY.

DURING THE OVERNIGHT HOURS ONLY FEW LIGHT PASSING SHOWER EXPECTED
OVER THE COASTAL WATERS BUT SO FAR NO PRECIPITATION IS FORECAST
OVER LAND. ON MONDAY MOSTLY FAIR WEATHER SKIES WILL PREVAIL ONCE
AGAIN AND PLEASANT SEASONAL TEMPERATURE EXPECTED THROUGH MOST OF THE
WORK WEEK. NO SIGNIFICANT WEATHER PATTERN IS FORECAST TO AFFECT THE
AREA WITH MOSTLY FAIR WEATHER SKIES EXPECTED...AND ONLY SLIGHT CHANCE
OF SOME EARLY MORNING AND LATE AFTERNOON SHOWERS EACH DAY.

&&

.AVIATION...VFR CONDS EXPECTED THROUGH THE NEXT 24 HOURS. VERY
LITTLE IF ANY SHRA ACTIVITY EXPECTED. WINDS MAINLY FROM THE NORTH TO
NORTHWEST BUT LIGHT...BECOMING VARIABLE OVERNIGHT. NO SIGNIFICANT
WEATHER HAZARDS EXPECTED.

&&

.MARINE...SEAS UP TO 6 FEET MAINLY OVER THE OFFSHORE ATLANTIC
WATERS...LESS THAN 6 FEET ELSE WHERE AS NORTHERLY SWELL CONTINUE
TO SUBSIDE. WINDS LESS THAN 10 KNOTS. SMALL CRAFT SHOULD EXERCISE
CAUTION ACROSS THE ATLANTIC WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 71 82 71 81 / 0 10 20 20
STT 70 85 72 85 / 10 10 10 10

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
509 AM AST MON DEC 8 2014

.SYNOPSIS...MID TO UPPER LEVEL AREA OF LOW PRESSURE AND ASSOCIATED
TROUGH ACROSS THE WEST CENTRAL ATLANTIC WILL CONTINUE TO MOVE
NORTH AWAY FROM THE LOCAL AREA. WEAK HIGH PRESSURE AT THE SURFACE
WILL CONTINUE TO DOMINATE THE LOCAL REGION. VERY DRY AIR WILL
CONTINUE ACROSS THE REGION THROUGH MID WEEK.

&&

.DISCUSSION...CLEAR SKIES PREVAILED ACROSS PUERTO RICO AND THE U.S
VIRGIN ISLANDS OVERNIGHT. LIGHT NORTHERLY WINDS COMBINED WITH FAIR
SKIES...RESULTED IN PLEASANT TEMPERATURES ACROSS THE REGION. LOCAL
AREA IS DOMINATE BY VERY DRY AIR AT ALL LEVEL OF THE ATMOSPHERE
WITH LATEST 08/00Z TJSJ SOUNDING SHOWING ONLY 0.99 INCHES IN
PRECIPITABLE WATER. IN FACT...GFS COMPUTER MODEL SUGGESTS THIS
VALUE WILL DROP TO 0.75 INCHES BY THIS AFTERNOON. MOISTURE
RECOVERY IS NOT EXPECTED UNTIL THURSDAY WHEN SURFACE WINDS SHIFT
FROM A MORE SOUTHERLY DIRECTION. HOWEVER...ANY RAIN WILL BE
LIMITED WITHOUT ANY SIGNIFICANT ACCUMULATIONS. IN THE LATER PART OF
THE WEEK...COMPUTER MODELS SUGGEST A FRONTAL MONDAY WILL APPROACH
THE LOCAL REGION FROM THE NORTHWEST...BRINGING BETTER CHANCES FOR
SHOWERS ACROSS THE REGION FOR NEXT WEEKEND.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THROUGH THE NEXT 24
HOURS. VERY LITTLE IF ANY SHRA ACTIVITY EXPECTED. LATEST TJSJ
SOUNDING INDICATED A LIGHT NORTHEAST WIND FLOW ALL THE WAY FROM THE
SURFACE TO 20K FEET...BUT STRONGER AND STILL FROM THE NORTHEAST
ABOVE 20K FEET.

&&

.MARINE...A LARGE SWELL EVENT WILL BEGIN TO AFFECT OUR LOCAL WATERS ON
TUESDAY. A MODERATE NORTHEAST SWELL WILL BEGIN TO AFFECT DURING
THE DAY ON TUESDAY BUT A LARGER WITH A MORE NORTH NORTHWEST
COMPONENT WILL BEGIN TO AFFECT THE LOCAL WATERS ON TUESDAY NIGHT.
THIS SECOND SWELL WILL GENERATE DANGEROUS MARINE CONDITIONS FOR
MARINERS AND BEACH GOERS. THIS SWELL WILL PEAK ON WEDNESDAY AND
THEN SLOWLY SUBSIDE THROUGH SATURDAY. SMALL CRAFT ADVISORIES AND
HIGH SURF ADVISORIES WILL BE ISSUED BY THE NATIONAL WEATHER
SERVICE AT SAN JUAN WFO IN THE NEXT 24 HOURS FOR THIS SWELL EVENT.



&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 81 72 83 73 / 10 20 20 10
STT 85 72 86 74 / 10 10 10 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
301 PM AST MON DEC 8 2014

.SYNOPSIS...DRY AIR EXPECTED TO CONTINUE OVER THE REGION FOR THE
REST OF TODAY WITH A SLIGHT INCREASE IN MOISTURE ON TUESDAY AND
WEDNESDAY AS THE WINDS SLOWLY SHIFT TO A MORE EASTERLY DIRECTION.
NORTHERLY SWELL TO INVADE THE LOCAL AREA LATE WEDNESDAY INTO WEDNESDAY.

&&

.DISCUSSION...THE BIG NEWS TODAY WERE THE MORNING TEMPERATURES
SINCE ACROSS THE LOCAL AREA THE TEMPERATURES WERE SEVERAL DEGREES
BELOW NORMAL. THE WINNER WAS ADJUNTAS WITH A MORNING TEMPERATURE
OF 49 DEGREES WHEN ITS NORMAL MINIMUM TEMPERATURE IS 57. HOWEVER
SEVERAL OTHER SECTORS ACROSS THE INTERIOR AND THE HIGHER
ELEVATIONS OF PUERTO RICO OBSERVED TEMPS IN THE 50S AND ACROSS THE
LOWER ELEVATIONS AND EVEN THE USVI...TEMPS IN THE UPPER 60S WERE
OBSERVED. SO OVERALL A COOLER THAN NORMAL MORNING. THIS WAS DUE TO
THE VERY LIGHT WINDS...DRY AIR AND CLEAR SKY. DAYTIME MAX
TEMPERATURE TODAY REACHED THE MID 80S ACROSS THE LOWER ELEVATIONS
BUT QUICKLY WENT DOWN TO THE LOWER 80S AS SOON AS THE NORTHERLY
WIND PICKED UP. CONDITIONS ARE FOR ANOTHER CLEAR AND PLEASANT NIGHT
WITH COOL TEMPS OVERNIGHT...MAYBE NOT QUITE AS COOL SINCE THE WIND
IS EXPECTED TO GET A BIT MORE EASTERLY AND THE MOISTURE IS
RISING...ALTHOUGH THE INCREASE IS VERY VERY SLIGHT.

IT IS NOT UNTIL WEDNESDAY WHEN WE SEE A MORE SIGNIFICANT INCREASE
IN MOISTURE AND THE WINDS TO BE A BIT STRONGER FROM THE EAST. THEN
THAT PATTERN SHOULD REMAIN IN PLACE THROUGH THE END OF THE WEEK
WITH FRIDAY BEING THE DAY WITH THE HIGHEST MOISTURE...ESPECIALLY
ACROSS THE USVI AND EASTERN PR.

&&

.AVIATION...VFR CONDS THRU PRD...WND LGT/VRB BLO FL200...FEW CU W
LGT PASSING SHOWER OVR OFFSHORE ATL WATERS. CLR ABV...SFC WND CALM
TO LGT/VRB. NO SIG OPERATIONAL WX OR AVN HAZARDS.

&&

.MARINE...LIGHT EASTERLY TRADE WINDS AND SEAS OF 5 FEET
OR LESS WILL PREVAIL TONIGHT. INCREASING HAZARDOUS SEAS AND SWELL
ACTION STILL FORECAST TO ARRIVE BY LATE TUESDAY THEN PEAK ON
WEDNESDAY AS NORTHERLY SWELLS ARRIVE AND SPREAD ACROSS THE LOCAL
WATERS. SMALL CRAFT ADVISORIES AS WELL AS...HIGH SURF ADVISORIES
WILL REMAIN LIKELY AT LEAST UNTIL THE END OF THE WORK WEEK. STAY
TUNED.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 84 73 83 / 10 10 10 10
STT 72 85 74 85 / 10 10 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
521 AM AST TUE DEC 9 2014

.SYNOPSIS...WEAK HIGH PRESSURE AT THE SURFACE WILL CONTINUE TO
DOMINATE THE LOCAL REGION. UPPER LEVEL RIDGE WILL REMAIN IN PLACE
THROUGH MOST OF THE WEEK. PATCHES OF LOW LEVEL MOISTURE WILL MOVE
ACROSS THE REGION DURING THE WEEKEND. FRONTAL BOUNDARY WILL APPROACH
THE REGION EARLY NEXT WEEK.

&&

.DISCUSSION...ONCE AGAIN...CLEAR SKIES PREVAILED ACROSS PUERTO
RICO AND THE U.S. VIRGIN ISLANDS OVERNIGHT. LOCAL AREA REMAINED
UNDER THE INFLUENCE OF A WEAK SURFACE HIGH PRESSURE...AND AN UPPER
LEVEL RIDGE. AS A RESULT...WEATHER CONDITIONS WILL REMAIN DRY
TODAY WITH VERY LITTLE SHOWER ACTIVITY EXPECTED TO DEVELOP.
SURFACE WINDS WILL SHIFT MORE EAST SOUTHEAST TODAY AS DEEP LOW
PRESSURE DEVELOPS JUST EAST OF THE EASTERN U.S COAST. THE
ASSOCIATED FRONTAL BOUNDARY WILL STAY NORTH OF THE AREA.

FOR LATE PART OF THE WEEK...PATCHES OF LOW LEVEL MOISTURE...EMBEDDED
IN THE TRADE WIND FLOW ARE EXPECTED TO AFFECT THE LOCAL AREA.
BETTER CHANCES FOR SHOWERS ARE THEN EXPECTED MAINLY ON
SATURDAY...AS MOISTURE INCREASES. FOR EARLY NEXT WEEK...GFS
COMPUTER MODEL INDICATED A FRONTAL BOUNDARY WILL APPROACH THE LOCAL
REGION FROM THE NORTHWEST. AN INCREASE IN CLOUDINESS AND SHOWER
ACTIVITY IS POSSIBLE MONDAY AND TUESDAY NEXT WEEK WITH THIS
FEATURE.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THROUGH THE NEXT 24
HOURS. NO SIG OPERATIONAL WX OR AVN HAZARDS. LIGHT TRADE WINDS
AROUND 10 KTS WITH SEA BREEZE VARIATIONS.

&&

.MARINE...INCREASING HAZARDOUS SEAS AND SWELL ACTION IS FORECAST TO
ARRIVE BY LATE TONIGHT THEN PEAK ON WEDNESDAY AS NORTHERLY SWELLS
ARRIVE AND SPREAD ACROSS THE LOCAL WATERS. SMALL CRAFT ADVISORY
IS IN EFFECT FOR THE ATLANTIC WATERS. A HIGH SURF ADVISORY WILL BE
IN EFFECT FOR THE NORTHERN COASTLINE OF PUERTO RICO...VIEQUES...
CULEBRA...SAINT THOMAS AND SAINT JOHN. REFER TO LATEST COASTAL
FLOOD PRODUCTS FOR LATEST INFORMATION.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 83 73 83 74 / 10 10 10 20
STT 85 73 86 75 / 10 10 10 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
256 PM AST TUE DEC 9 2014

.SYNOPSIS...UPPER LEVEL RIDGE WILL REMAIN IN PLACE THROUGH MOST
OF THE WEEK. AREA OF SLIGHTLY HIGHER LOW LEVEL MOISTURE WILL
SLOWLY MOVE ACROSS THE REGION AS THE WEEK PROGRESSES. FRONTAL
BOUNDARY WILL APPROACH THE REGION EARLY NEXT WEEK.

&&

.DISCUSSION...ONCE AGAIN A FAIR WEATHER DAY WAS OBSERVED TODAY
ACROSS THE LOCAL ISLANDS. A FEW CLOUDS WITH ONLY ISOLATED SHOWERS
DURING THE DAY. IN THE MORNING HOURS THOUGH THE MINIMUM
TEMPERATURES WERE LOWER THAN NORMAL BUT EITHER EQUAL OR SLIGHTLY
HIGHER THAN THE MINIMUM TEMPS OBSERVED YESTERDAY MORNING. THIS WAS
EXACTLY WHAT WE EXPECTED. NOW THE EASTERLY WINDS ARE SLOWLY
RETURNING TO THE LOCAL AREA ALTHOUGH THEY SHOULD STILL BE LIGHT.
IN ADDITION...MOISTURE WILL SLIGHTLY INCREASE OR REMAIN
STEADY...WHICH MEANS THAT WE EXPECT SIMILAR CONDITIONS AGAIN
TONIGHT AND OVERNIGHT. SLIGHT CHANCE OF SHOWERS AND COOLER THAN
NORMAL MINIMUM TEMPS.

HOWEVER THE BIG STORY REALLY IS THE NORTHERLY SWELL THAT WILL
DETERIORATE THE MARINE CONDITIONS AND GIVE US HIGH SURF
CONDITIONS. SEAS ARE EXPECTED TO GET TO 8 FEET ACROSS THE ATLANTIC
WATERS LATER TONIGHT AND DANGEROUS SURF CONDITIONS ARE EXPECTED TO
START TONIGHT...PEAKING WEDNESDAY MORNING AND SLOWLY SUBSIDING
THROUGH THURSDAY. BREAKING WAVES OF 12 TO 16 FEET ARE POSSIBLE.

WEATHER WISE WE EXPECT A SLIGHT INCREASE IN THE LOW LEVEL MOISTURE
AS THE WEEK PROGRESSES BUT SIGNIFICANT SHOWERS ARE NOT ANTICIPATED
AT THIS TIME. PASSING ISOLATED TO MAYBE SCATTERED SHOWERS ARE
ABOUT WHAT WE SHOULD EXPECT WITH THIS INCREASE IN
MOISTURE...MORNING SHOWERS ACROSS EASTERN PR AND THE USVI WHILE
SHOWERS POSSIBLE ACROSS THE INTERIOR AND WESTERN SECTIONS OF PR IN
THE AFTERNOON...AGAIN...NOT SIGNIFICANT AMOUNTS AND NOT OF LONG
DURATION.


&&

.AVIATION...VFR CONDS EXPECTED THROUGH THE NEXT 24 HOURS. NO SIG
OPERATIONAL WX OR AVN HAZARDS. LIGHT TRADE WINDS AROUND 10 KTS BLO
FL200...BCMG FM W AND INCR W/HT ABV. LGT/VRB AT SFC FM
09/19Z-10/14Z...WITH SEA BREEZE VARIATIONS AFT 10/15Z.


&&

.MARINE...LONG PERIOD NORTHERLY SWELL EXPECTED TO INVADE THE LOCAL
AREA TONIGHT AND CONTINUE THROUGH THURSDAY...BUT PEAKING
WEDNESDAY MORNING. THIS WILL CAUSE SEAS OF UP TO 8 FEET AND HAZARDOUS
SURF CONDITIONS. SMALL CRAFT AND HIGH SURF ADVISORIES ARE IN
EFFECT STARTING TONIGHT. DANGEROUS RIP CURRENTS ARE ALSO POSSIBLE.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 83 74 83 / 10 10 20 20
STT 73 86 75 86 / 10 10 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
540 AM AST WED DEC 10 2014

.SYNOPSIS...MID TO UPPER LEVEL HIGH PRESSURE RIDGE WILL HOLD MOST OF
THE WEEK. THIS RIDGE ALOFT WILL MAINTAIN THE FAIR WEATHER PATTERN ACROSS
THE LOCAL REGION THROUGH THE END OF THE WEEK. A SHEARLINE/FRONTAL
TROUGH WILL REACH THE NORTHEAST CARIBBEAN REGION NEXT WEEK...FAVORING
THE LOW LEVEL CONVERGENCE AND MOISTURE TRANSPORT ACROSS THE LOCAL ISLANDS.

&&

.DISCUSSION...LIGHT LAND BREEZES DURING OVERNIGHT HOURS RESULTED IN
MOSTLY CLEAR AND SOMEWHAT COOL CONDITIONS ACROSS THE LOCAL ISLANDS.
A FAIRLY STRONG MID-UPPER RIDGE HAVE KEPT A STABLE ATMOSPHERE ACROSS
THE ISLANDS. IN ADDITION...PRECIPITABLE WATER VALUES ARE RUNNING
NEAR 1.25 INCH...ABOUT 10 TO 20 PERCENT BELOW NORMAL FOR DECEMBER.
MODELS AGREE ON FAIR WEATHER CONDITIONS PREVAILING ACROSS THE
FORECAST AREA THROUGH THE END OF THE WORK WEEK. UNDER THE INFLUENCE
OF A MID LEVEL RIDGE...A FAIRLY STRONG SUBSIDENCE CAP WILL TRAP THE
MOISTURE AT LOW LEVELS...LIMITING THE ORGANIZED CONVECTION ACROSS
THE FORECAST AREA THROUGH THE WEEKEND. ALTHOUGH...MODERATE EASTERLY
TRADES ARE EXPECTED TO RETURN TO THE FORECAST AREA THURSDAY AND
FRIDAY...THE ABSENCE OF MESO-SYNOPTIC FORCING WILL KEEP THE RAINFALL
AMOUNTS RELATIVELY LOW. OVERALL...THE REST OF THE WEEK...EXPECT A
FEW SHOWERS AFFECTING THE WINDWARD SIDE OF THE ISLANDS FROM TIME TO
TIME AND ISOLATED SHALLOW CONVECTION DEVELOPING OVER WESTERN PR IN
THE AFTERNOON.

FOR EARLY NEXT WEEK...A WEAK COLD FRONT AND ITS ASSOCIATED SHEARLINE
WILL REACH THE NORTHEAST CARIBBEAN ON MONDAY...INCREASING THE
MOISTURE CONTENT AND ENHANCING THE LOW LEVEL CONVERGENCE ACROSS
THE LOCAL REGION. THIS WILL RESULT IN ADDITIONAL CLOUDS AND SHOWERS
AFFECTING THE ISLANDS LATE SUNDAY INTO MONDAY. THE FRONTAL BOUNDARY
IS FORECAST TO CROSS PUERTO RICO LATE MONDAY WHILE SLOWLY DISSIPATES.
MOISTURE ASSOCIATED WITH THE BOUNDARY WILL LINGER NEAR THE ISLANDS
THROUGH MIDWEEK.

&&

.AVIATION...VFR CONDITIONS EXPECTED TROUGH THE FORECAST PERIOD.
LIGHT EAST TO SOUTHEAST WINDS WILL PREVAIL BELOW FL100.

&&

.MARINE...LARGE...LONG PERIOD NORTHERLY SWELLS OF 7-9 FT WILL
CONTINUE TO AFFECT THE REGIONAL WATERS THROUGH THURSDAY NIGHT.
SWELL ACTION EXPECTED TO PEAK LATER TODAY...AND SLOWLY SUBSIDE
LATE THURSDAY INTO FRIDAY. THESE LARGE SWELLS WILL PRODUCE
DANGEROUS SURF CONDITIONS...STRONG RIP CURRENTS...MINOR COASTAL
EROSION AS WELL AS COASTAL FLOODING IN LOW LYING AREAS ALONG THE
NORTH COAST. THEREFORE...A HIGH SURF ADVISORY AND THE COASTAL
FLOOD WATCH IS IN EFFECT FOR THE NORTH FACING COASTS OF PR AND
NORTHERN USVI.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 85 72 84 74 / 10 20 20 30
STT 85 74 86 76 / 20 30 30 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
255 PM AST WED DEC 10 2014

.SYNOPSIS...COLD FRONT CONTINUED TO MOVE EASTWARDS ACROSS THE WESTERN
ATLANTIC AND EXTENDS SOUTHWARDS ACROSS EASTERN CUBA...THEN INTO THE
NORTHWESTERN CARIBBEAN. FRONT IS TO GRADUALLY WEAKEN WITH ASSOCIATED
SHEAR LINE TO STALL NORTH OF THE REGION OVER THE NEXT FEW DAYS.
SURFACE HIGH PRESSURE RIDGE EAST AND NORTHEAST OF THE REGION TODAY
WILL GRADUALLY BUILD EASTWARD ACROSS THE FORECAST AREA OVER THE NEXT
FEW DAYS. THIS WILL RESULT IN A SLIGHT INCREASE IN THE EASTERLY TRADE
WINDS DURING THE REST OF THE WORK WEEK. IN THE MEANTIME...A LIGHT EAST
SOUTHEAST WIND FLOW PREVAILED ACROSS THE REGION TODAY. IN THE UPPER
LEVELS...BROAD HIGH PRESSURE RIDGE EXTENDING ACROSS THE REGION WILL
REMAIN IN PLACE THROUGH THE UPCOMING WEEKEND.

&&

.DISCUSSION...MOSTLY FAIR WEATHER CONTINUE TO PREVAIL ACROSS THE
REGION WITH PLEASANT SEASONAL AFTERNOON TEMPERATURES. A FEW SHOWERS
FORMED ACROSS PARTS OF THE INTERIOR AND EAST COASTAL SECTION OF
PUERTO RICO DURING THE AFTERNOON... BUT MOST WERE OF SHORT DURATION
WITH NO SIGNIFICANT RAINFALL ACCUMULATIONS OBSERVED OR REPORTED.
SATELLITE IMAGERY SHOWED MOSTLY THIN HIGH LEVEL CLOUDS STREAMING
WEST ACROSS THE REGION...WHILE FEW SHALLOW LOW LEVEL CLOUDS FORMED
AND MOVED EASTWARD ACROSS THE ISLANDS AND SURROUNDING WATERS IN
THE PREVAILING WIND FLOW. RECENT TJSJ 09/12Z UPPER AIR SOUNDING
AS WELL AS SATELLITE DERIVED BLENDED PRECIPITABLE WATER PRODUCTS
SHOWED SLIGHT INCREASE IN PWAT VALUES TODAY TO NEAR 1.30 INCHES.
OVERALL HOWEVER STILL DRY AND STABLE CONDITIONS PREVAILED.


DURING THE REST OF THE EVENING AND OVERNIGHT HOURS ONLY FEW LIGHT
PASSING SHOWER EXPECTED OVER THE COASTAL WATERS...WHILE GRADUAL
CLEARING CAN BE EXPECTED OVER LAND. MOSTLY FAIR WEATHER SKIES
EXPECTED ON THURSDAY HOWEVER SLIGHT INCREASE IN EASTERLY TRADE
WINDS WILL BRINGS PATCHES OF TRADE WIND MOISTURE ACROSS THE REGION.
THIS WILL AID IN SOME LOCALLY AND DIURNALLY INDUCED AFTERNOON CONVECTION
MAINLY OVER PARTS OF THE INTERIOR AND WEST SECTIONS OF PUERTO RICO.
ELSEWHERE AND OVER THE VIRGIN ISLANDS...MOSTLY FAIR WEATHER SKIES WILL
PREVAIL.

SO FAR BASED ON LATEST MODEL GUIDANCE...NO SIGNIFICANT WEATHER
FEATURE IN SIGHT AT LEAST THOUGH THE UPCOMING WEEKEND...HOWEVER BY
EARLY NEXT WEEK...A SHORT WAVE TROUGH AND A FRONTAL SHEAR LINE IS
TO APPROACH THE REGION AND BRING AN INCREASE IN INSTABILITY AND
MOISTURE TO THE REGION...THUS INCREASING THE CHANCES FOR SHOWERS
AND POSSIBLY ISOLATED THUNDERSTORMS ACTIVITY ACROSS THE FORECAST
AREA. MORE TO COME ON THIS LATER AND WILL CONTINUE TO SEE HOW THIS
PATTERN UNFOLDS.

&&

.AVIATION...VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS
ACROSS ALL TERMINALS. LOW LEVEL CLOUDINESS AND -SHRA OVER MAINLAND PR
WILL CREATE MOUNTAIN OBSCURATIONS AND SCT CIGS BELOW FL080 UNTIL
10/23Z...SCT-BKN LAYERS AT FL250 WITH STRONG WESTERLIES. A LIGHT
LOW LEVEL EASTERLY WIND FLOW WILL CONTINUE.

&&

.MARINE...LONG PERIOD NORTHERLY SWELLS BETWEEN 7 TO 9 FEET WILL
CONTINUE TO AFFECT THE ATLANTIC COASTS OF PUERTO RICO...CULEBRA...
VIEQUES AND NORTHERN U.S. VIRGIN ISLANDS THROUGH AT LEAST THURSDAY
NIGHT. THE LARGE...LONG PERIOD SWELLS ARE EXPECTED TO PEAK OVERNIGHT
THROUGH EARLY THURSDAY. THEREFORE...EXPECT SIGNIFICANT BREAKING WAVE
ACTION AND DANGEROUS STRONG RIP CURRENTS TO AFFECT THE NORTH FACING
BEACHES OF PUERTO RICO...CULEBRA...VIEQUES AND THE NORTHERN U.S.
VIRGIN ISLANDS. A HIGH SURF ADVISORY AND COASTAL FLOOD WATCH REMAINS
IN EFFECT FOR THESE AREAS. SMALL CRAFT ADVISORIES ALSO REMAIN IN
EFFECT FOR ALL OF THE LOCAL WATERS AND THE MONA PASSAGE OVERNIGHT
THROUGH THURSDAY. PLEASE REFER TO THE LATEST COASTAL WATERS...MARINE
WEATHER MESSAGE FOR ADDITIONAL AND LATEST UP TO DATE INFORMATION.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 84 74 83 / 20 20 30 30
STT 74 87 76 85 / 30 30 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
536 AM AST THU DEC 11 2014

.SYNOPSIS...RIDGE PATTERN IS TO GENERALLY HOLD OVER THE NEXT FEW
DAYS...MAINTAINING A GENERALLY FAIR WEATHER CONDITIONS ACROSS THE
LOCAL ISLANDS. SOME WEAKENING OF THE SUBEQUATORIAL RIDGE IS EXPECTED
DURING THE WEEKEND AS A BROAD TROUGH MOVE INTO THE WESTERN ATLANTIC.
A SHEARLINE/FRONTAL TROUGH WILL APPROACH THE NORTHEAST CARIBBEAN
REGION ON SUNDAY...ENHANCING THE LOW LEVEL CONVERGENCE AND MOISTURE
TRANSPORT ACROSS PUERTO RICO AND U.S. VIRGIN ISLANDS.

&&

.DISCUSSION...SATELLITE AND RADAR IMAGERY SHOWED SCATTERED SHOWERS
MAINLY ACROSS THE REGIONAL WATERS. SOME SHOWERS AFFECTED NORTHWEST
PR NEAR MIDNIGHT. THE SKIES GRADUALLY CLEAR OUT OVER THE ISLANDS
DURING THE OVERNIGHT HOURS...ALLOWING TEMPERATURES TO DROP AROUND
60-65 DEGREES OVER THE INTERIOR AND MOUNTAIN SECTIONS OF PUERTO
RICO. FAIRLY DRY AND STABLE ATMOSPHERE IS EXPECTED TO CONTINUE
ACROSS THE LOCAL ISLANDS OVER THE NEXT FEW DAYS. LATEST SATELLITE
BLENDED TPW ANALYSIS SHOWS MOISTURE ACROSS PUERTO RICO AND THE
USVI ABOUT 10 PERCENT BELOW NORMAL FOR DECEMBER. GENTLE EASTERLY
TRADES ARE FORECAST TO PERSIST THROUGH SATURDAY. THEN...SURFACE
WINDS BECOME LIGHT AND VARIABLE SUNDAY THROUGH EARLY NEXT WEEK AS A
FRONTAL BOUNDARY APPROACHES FORM THE NORTHWEST. THE FRONTAL BOUNDARY
AND ITS ASSOCIATED SHEARLINE WILL REACH THE NORTHEAST CARIBBEAN
REGION LATE SUNDAY INTO MONDAY...INCREASING THE CHANCES OF SHOWERS
AND THUNDERSTORMS ACROSS THE FORECAST AREA. MOISTURE ASSOCIATED
WITH THE FRONTAL BOUNDARY IS FORECAST TO LINGER OVER PUERTO RICO
AND THE U.S. VIRGIN ISLANDS UNTIL TUESDAY. WEATHER CONDITIONS
IMPROVE AGAIN BY MIDWEEK NEXT WEEK.

&&

.AVIATION...MOSTLY VFR CONDS EXPECTED THROUGH THE NEXT 24 HOURS
WITH LIGHT TRADE WINDS AROUND 10 KTS WITH SEA BREEZE VARIATIONS
AFT 11/15Z. AN ISOLATED SHOWER OR TWO POSSIBLE NEAR TJMZ AFT 10/17Z.

&&

.MARINE... A LARGE...LONG PERIOD NORTHERLY SWELLS OF 7-9 FEET WILL
CONTINUE TO AFFECT THE ATLANTIC WATERS THROUGH AT LEAST FRIDAY NIGHT.
AS A RESULT...A HIGH SURF ADVISORY AND COASTAL FLOOD ADVISORY REMAIN
IN EFFECT FOR THE NORTH FACING COASTS OF PR AND USVI. SMALL CRAFT
ADVISORIES ALSO REMAIN IN EFFECT FOR ALL OF THE WATERS...EXCEPT
THE COASTAL WATERS OF SOUTHWEST AND SOUTH PR. PLEASE REFER TO THE
LATEST COASTAL WATERS...MARINE WEATHER MESSAGE FOR ADDITIONAL
INFORMATION.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 75 84 72 / 10 30 30 20
STT 85 75 86 74 / 20 30 30 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
253 PM AST THU DEC 11 2014

.SYNOPSIS...BROAD HIGH PRESSURE RIDGE EXTENDING NORTHWARD ACROSS THE
AREA FROM THE CARIBBEAN BASIN WILL REMAIN THE DOMINANT FEATURE
ACROSS THE REGION AT LEAST THROUGH SATURDAY. THIS WILL RESULT IN
SUBSIDENT AND STABLE UPPER LEVEL ATMOSPHERE WITH FAIRLY STRONG CAP
INVERSION ACROSS THE FORECAST AREA.SURFACE HIGH PRESSURE RIDGE IS
TO REMAIN IN PLACE ACROSS THE EAST AND NORTHEAST ATLANTIC TO MAINTAIN
A LIGHT TO MODERATE EASTERLY TRADE WIND FLOW ACROSS THE NORTHEASTERN
CARIBBEAN THROUGH AT LEAST SATURDAY. RIDGE WILL THEN GRADUALLY
WEAKEN SUNDAY THROUGH MONDAY AS FRONTAL TROUGH MOVES ACROSS THE
WESTERN ATLANTIC AND APPROACHES REGION FROM THE WEST. UPPER RIDGE
IS TO ALSO ERODE BY SUNDAY AS A POLAR TROUGH WILL MOVE EASTWARD ACROSS
THE WESTERN ATLANTIC.

&&

.DISCUSSION...MOSTLY FAIR WEATHER SKIES PREVAILED ACROSS THE REGION
WITH LIGHT WINDS AND PLEASANT DAYTIME TEMPERATURES. LIMITED OR NO
SHOWER ACTIVITY WAS OBSERVED OVER THE ISLANDS TODAY...AND THOSE THAT
WERE OBSERVED WERE OF LIGHT INTENSITY AND OF SHORT DURATION. SATELLITE
IMAGERY SHOWED MOSTLY SHALLOW LOW LEVEL MOISTURE MOVING WEST ACROSS
THE REGION WITH MOST CLEAR SKIES ABOVE. PREVIOUS TJSJ 10/12Z UPPER
AIR SOUNDING AS WELL AS SATELLITE DERIVED BLENDED PRECIPITABLE WATER
PRODUCTS SHOWED IN PWAT VALUES TODAY TO NEAR 1.20 INCHES EVEN DRIER
THAN YESTERDAY...AS OVERALL DRY AND SUBSIDENT CONDITIONS PREVAILED.

AS PREVIOUSLY MENTIONED....LONG WAVE POLAR TROUGH WILL MOVE ACROSS
THE WEST ATLANTIC...BECOME AMPLIFIED THROUGH SATURDAY AND EVENTUALLY
BREAK DOWN THE RIDGE ALOFT BY SUNDAY INTO MONDAY OF NEXT WEEK. THIS
WILL BE SUPPORTED BY THE AFOREMENTIONED FRONTAL TROUGH AND ASSOCIATED
SHEAR LINE WHICH WILL APPROACH THE REGION SUNDAY INTO MONDAY. MODELS
CONTINUE TO SUGGEST SLIGHT INCREASE IN LAYERED MOISTURE. THEREFORE
STILL EXPECT BETTER CHANGE FOR SHOWER AND ISOLATED THUNDERSTORM
DEVELOPMENT DURING THAT TIME...AS PREFRONTAL TROUGHINESS AND
MOISTURE CONVERGENCE FORECAST TO MOVE ACROSS THE REGION EARLY
NEXT WEEK INCREASING PWAT VALUES TO AROUND 1.70 INCHES OR SO.

IN THE MEANTIME...LIGHT TO MODERATE EASTERLY TRADES ARE TO PREVAIL
OVER THE NEXT FEW DAYS. THIS WILL BRING PERIODS OF PASSING TRADE WIND
SHOWERS ACROSS THE ISLANDS AND SURROUNDING WATERS DURING THE LATE EVENING
AND EARLY MORNING HOURS. THIS WILL ONCE AGAIN BE FOLLOWED BY ISOLATED
TO SCATTERED AFTERNOON CONVECTION MAINLY ACROSS PARTS OF THE WEST INTERIOR
SECTIONS OF PUERTO RICO. ELSEWHERE... MOSTLY FAIR WEATHER SKIES ARE
EXPECTED FOR THE NEXT SEVERAL DAYS EXCEPT FOR A FEW STREAMER LIKE CLOUDS
AND ACCOMPANYING SHOWER ACTIVITY OVER PARTS OF THE ISLANDS.

&&

.AVIATION...VFR CONDS EXPECTED DURG THE NEXT 24 HOURS. E-NE TRADE
WINDS 10-15 KTS BLOW FL150 BCMG FM W AND INCR W/HT ABV TO MAX WND
BTW 70-80 KTS NR FL400. SFC WND LGT FM E EXCEPT FO LOCAL SEA BREEZE
VARIATIONS WITH HIGHER GUSTS ALONG THE COASTAL AREAS. FEW LGT -SHRA
OVR W INTERIOR SECTIONS OF PR PSBL TIL 11/21Z... SCT SHALLOW CLD LYRS
BLO FL100...CLR ABV. NO SIG OPERATIONAL WX IMPACTS ATTM.

&&

.MARINE...LONG PERIOD NORTHERLY SWELLS OF 6-8 FEET WILL CONTINUE
TO AFFECT THE ATLANTIC WATERS THROUGH AT LEAST FRIDAY NIGHT. AS A
RESULT...A HIGH SURF ADVISORY WILL REMAIN IN EFFECT FOR THE NORTH
FACING COASTS OF PR AND USVI. THE COASTAL FLOOD ADVISORY FOR COASTAL
FLOODING HAS BEEN ALLOWED TO EXPIRE AT 2 PM AST TODAY AS COASTAL
FLOODING IS NO LONGER EXPECTED. SMALL CRAFT ADVISORIES ALSO REMAIN
IN EFFECT FOR ALL OF THE WATERS...EXCEPT THE COASTAL WATERS OF
SOUTHWEST AND SOUTH PR. PLEASE REFER TO THE LATEST COASTAL WATERS
FORECAST AND MARINE WEATHER MESSAGES FOR ADDITIONAL INFORMATION.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 84 72 83 / 30 30 20 20
STT 75 86 75 85 / 30 30 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
522 AM AST FRI DEC 12 2014

.SYNOPSIS...RIDGE ALOFT WILL WEAKEN DURING THE UPCOMING WEEKEND...
AS DEEP TROUGH MOVES ACROSS THE WESTERN ATLANTIC WITH ASSOCIATED
FRONT REACHING THE AREA EARLY NEXT WEEK.

&&

.DISCUSSION...MOSTLY CLEAR TO PARTLY CLOUDY SKIES PREVAILED
ACROSS THE LOCAL ISLANDS OVERNIGHT...WITH BRIEF SHOWERS OBSERVED
OVER THE REGIONAL WATERS. WINDS WERE LIGHT AND VARIABLE WITH
COASTAL TEMPERATURES IN THE MID TO UPPER 70S.

MOSTLY FAIR WEATHER WILL CONTINUE TO PREVAIL ACROSS THE LOCAL
ISLANDS FRIDAY AND SATURDAY WITH TRADE WIND SHOWERS ACROSS
WINDWARD AREAS FROM TIME TO TIME...FOLLOWED BY SHALLOW AFTERNOON
CONVECTION ACROSS WESTERN PUERTO RICO UNDER WEAKENING RIDGE
ALOFT...MODERATE EASTERLY WINDS AND NEAR NORMAL PRECIPITABLE
WATER VALUES.

AS DEEP TROUGH MOVES ACROSS THE WESTERN ATLANTIC EARLY NEXT WEEK...
PREFRONTAL TROUGH WILL MOVE ACROSS THE AREA SUNDAY FOLLOWED BY
THE FRONTAL PASSAGE ON MONDAY. THEREFORE...A BETTER CHANCE OF
SHOWER ACTIVITY IS THEN EXPECTED WITH SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS POSSIBLE SUNDAY AND MONDAY. THE HEAVIEST
SHOWERS WILL BE FOCUSED OVER AND NORTH OF THE CORDILLERA BOTH
DAYS. LINGERING MOISTURE STILL EXPECTED EARLY TUESDAY...HOWEVER
A SHARP DECREASE IS ANTICIPATED LATE TUESDAY AND WEDNESDAY.
THEREFORE BY MID WEEK EXPECT MOSTLY FAIR WEATHER CONDITIONS WITH
FEW PASSING SHOWERS AND PLEASANT TEMPERATURES UNDER NORTHERLY
WINDS AND A MUCH DRIER AIR MASS.

&&

.AVIATION...VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS
ACROSS THE LOCAL TERMINALS. PASSING SHOWERS ARE EXPECTED ACROSS
TNCM/TKPK/TIST/TJSJ/TISX EARLY IN THE MORNING. CLOUDS AND SHRA
DEVELOPING OVER MAINLAND PR AFTER 12/17Z...CREATING MOUNTAIN
OBSCURATIONS AND BRIEF MVFR CONDS MAINLY OVER TJMZ. LIGHT TO CALM
AND VARIABLE WINDS UNTIL 12/13Z...AFT 12/13Z WINDS WILL STRENGTHEN
TO 5-15 KNOTS WITH HIGHER GUSTS IN/AROUND SHRA.

&&

.MARINE...LARGE NORTHERLY SWELLS WILL CONTINUE TO AFFECT THE LOCAL
WATERS THROUGH TONIGHT...THEN SLOWLY SUBSIDING ON SATURDAY. EXPECT
SWELLS OF 6 TO 8 FEET WITH BREAKING WAVES OF 12 TO 14 FEET TODAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 85 74 85 74 / 20 20 20 10
STT 86 74 86 74 / 20 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
308 PM AST FRI DEC 12 2014

.SYNOPSIS...RIDGE PATTERN IS TO GENERALLY HOLD THROUGH SATURDAY...
MAINTAINING A RELATIVELY FAIR WEATHER CONDITIONS ACROSS THE LOCAL
ISLANDS. SOME WEAKENING OF THE RIDGE IS EXPECTED ON SUNDAY AS A
BROAD TROUGH MOVE INTO THE WESTERN ATLANTIC. A SHEARLINE/FRONTAL
TROUGH WILL REACH THE LOCAL REGION ON SUNDAY...INCREASING THE
CLOUDINESS AND THE CHANCES OF SHOWERS ACROSS PUERTO RICO AND THE
U.S. VIRGIN ISLANDS.

&&

.DISCUSSION...SATELLITE AND RADAR IMAGERY SHOWED SCATTERED SHOWERS
AND A FEW THUNDERSTORMS DEVELOPING ACROSS WESTERN INTERIOR...WEST AND
PORTIONS OF THE SAN JUAN METRO AREA. THE HEAVIEST SHOWERS WERE
OBSERVED OVER MOCA...SAN SEBASTIAN AND ANASCO. THIS ACTIVITY WILL
TAPER OFF JUST BEFORE SUNSET...LEAVING THE PARTLY CLOUDY SKIES
ACROSS MOST OF PUERTO RICO THIS EVENING. FOR TONIGHT...A FEW TRADE
WIND SHOWERS WILL MOVE OVER THE WINDWARD SIDE OF THE ISLANDS...
BRINGING BRIEF PERIODS OF LIGHT TO MODERATE RAINFALL ACROSS THE EAST
PORTIONS OF THE ISLANDS FROM TIME TO TIME. FOR SATURDAY...WEATHER
CONDITIONS WILL REMAIN FAIRLY STABLE AS RIDGE ALOFT DOMINATES THE
NORTHEAST CARIBBEAN REGION. HOWEVER...SEA BREEZE CONVERGENCE OVER
WESTERN PUERTO RICO WILL INDUCE THE DEVELOPMENT OF SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS SATURDAY AFTERNOON.

FOR SUNDAY THROUGH EARLY NEXT WEEK...A WEAK COLD FRONT AND ITS
ASSOCIATED SHEARLINE WILL REACH THE NORTHEAST CARIBBEAN...INCREASING
THE MOISTURE CONTENT AND ENHANCING THE LOW LEVEL CONVERGENCE ACROSS
THE LOCAL REGION. THIS WILL RESULT IN ADDITIONAL CLOUDS AND SHOWERS
AFFECTING THE ISLANDS LATE SUNDAY INTO MONDAY. MOISTURE ASSOCIATED
WITH THE FRONTAL BOUNDARY IS FORECAST TO LINGER OVER THE FORECAST
AREA THROUGH TUESDAY WHILE DISSIPATES. DRIER AND MORE STABLE
CONDITIONS WILL RETURN WEDNESDAY TO FRIDAY.

&&

.AVIATION...VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24 HOURS
ACROSS THE LOCAL TERMINALS. +SHRA ALONG THE MOUNTAIN RANGES OF
MAINLAND PR WILL CONTINUE TO CREATE MOUNTAIN OBSCURATIONS AND BRIEF
MVFR CONDS. VCSH EXPECTED ACROSS ALL TERMINALS UNTIL AT LEAST
13/00Z. LOW LEVEL EASTERLIES WILL CONTINUE AT 10-15 KNOTS...THEN
LIGHT AND VARIABLE OVERNIGHT.

&&

.MARINE...MODEL GUIDANCE AS WELL AS OBSERVATIONS INDICATE THAT
THE SEA CONDITIONS ARE IMPROVING AND WILL CONTINUE IMPROVE DURING
THE WEEKEND. THEREFORE...THE HIGH SURF ADVISORY WAS CANCELLED
EARLY THIS AFTERNOON. HOWEVER...RIP CURRENTS REMAIN LIKELY ACROSS
THE NORTHERN COASTS OF PUERTO RICO AND THE U.S. VIRGIN ISLANDS
THROUGH TONIGHT. SMALL CRAFT ADVISORIES ARE STILL IN EFFECT FOR
THE ATLANTIC WATERS AND CARIBBEAN PASSAGES.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 85 74 85 / 20 20 20 50
STT 74 86 74 86 / 20 20 30 30