Caribbean - Central America Weather

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1004 PM AST SUN JAN 12 2014

.UPDATE...VERY DRY WEATHER CONDITIONS PREVAILED ACROSS THE LOCAL
AREA TONIGHT. ONLY VERY LIGHT PASSING SHOWERS WERE NOTED...MAINLY
OVER THE COASTAL WATERS. A PATCH OF LOW LEVEL MOISTURE IS EXPECTED
TO AFFECT THE LOCAL ISLANDS EARLY MONDAY. FORECAST IS ON TRACK
WITH ONGOING WEATHER SITUATION. NO CHANGES NEEDED TO FORECAST
GRIDS TONIGHT.

&&

.AVIATION...ISOLD SHRA TONITE AT PR/USVI AND SCT FOR LEEWARDS. MON
MRNG WL SEE SCT SHRA PR/USVI AND ISOLD SHRA LEEWARDS. MOST SHRA WL
NOT REDUCE CONDS BLW VFR AND WL OTW BE BRF. SHRA TO BE ISOLD AT
MOST TUE/WED. WINDS BLW FL100 E 15-22 KT THRU MON.


&&

.MARINE...LATEST BUOY OBSERVATIONS INDICATED SEAS HAS DIMINISH
BELOW SMALL CRAFT ADVISORY CRITERIA. THEREFORE...THE SMALL CRAFT
ADVISORY EXPIRED AT 9 PM AST THIS EVENING. HOWEVER...CHOPPY SEAS WILL
CONTINUE ACROSS MOST COASTAL WATERS. SMALL CRAFT SHOULD EXERCISE
CAUTION DUE TO SEAS UP TO 6 FEET AND WINDS UP TO 20 KNOTS.

[cycloneye]

Good morning. Trade wind showers will continue to move thru PR and VI today.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
531 AM AST MON JAN 13 2014

.SYNOPSIS...AT UPPER LEVELS...HIGH PRESSURE OVER THE SOUTHWEST
CARIBBEAN WILL EDGE EASTWARD DURING THE WEEK AND PASS THROUGH
PUERTO RICO AND THE U.S. VIRGIN ISLANDS ON FRIDAY AND THE LEEWARD
ISLANDS ON SATURDAY NIGHT. THIS WILL BRING SOUTHWEST FLOW TO
TO THE AREA.

AT MID LEVELS...HIGH PRESSURE OVER THE GREATER ANTILLES WILL MOVE
INTO THE EASTERN CARIBBEAN LATER IN THE WEEK. SLIGHTLY COOLER AIR
WILL PUSH INTO THE AREA FROM THE NORTH TUESDAY NIGHT AND
WEDNESDAY...BUT THE ATMOSPHERE AT MID LEVELS WILL REMAIN DRY
THROUGH EARLY NEXT WEEK WHILE IT WARMS AGAIN.

AT LOWER LEVELS...HIGH PRESSURE AND MODERATE TO FRESH TRADE WINDS
WILL DOMINATE THE LOCAL AREA. A TROUGH OVER THE WINDWARD PASSAGE
ON FRIDAY WILL MOVE OVER THE LOCAL AREA EARLY NEXT WEEK IN
RESPONSE TO LOWER PRESSURE OVER THE WESTERN ATLANTIC THEN.

&&

.DISCUSSION...SHOWERS INCREASED WITH THE BAND OF MOISTURE
APPROACHING THE AREA AFTER THE MIDNIGHT SHAKE UP THAT WOKE MANY
PEOPLE BUT CAUSED ONLY MINOR DAMAGE FROM REPORTS SEEN SO FAR. NO
TSUNAMIS WERE DETECTED. SHOWERS ARE EXPECTED TO INCREASE DURING
THE MORNING HOURS...BUT THE BAND WILL PASS EASTERN PUERTO RICO BY
EARLY AFTERNOON AND SUNNY SKIES SHOULD ENSUE. THERE WILL ALSO BE
SCATTERED SHOWERS IN WESTERN PUERTO RICO AND THE INTERIOR. BANDS OF
MOISTURE CONTINUE TO PEEL OFF OF A FRONTAL ZONE IN THE WEST
CENTRAL ATLANTIC THAT WILL AFFECT THE AREA TUESDAY THROUGH
THURSDAY...BUT THE MOST MOISTURE WILL OCCUR ON THURSDAY. A FEW
SHOWERS EACH DAY SEEM UNAVOIDABLE DESPITE THE DRYING ATMOSPHERE
AND THE GFS IS SHOWING A BOUNDARY MOVING THROUGH THE AREA ON
TUESDAY NIGHT AND WEDNESDAY THAT WILL CAUSE MOISTURE TO INCREASE.
SINCE THE MOISTURE IS QUITE SHALLO...SHOWERS...FOR THOSE THAT GET
THEM WILL BE LIGHT. WARMER...MOIST AIR RETURNS TO THE AREA EARLY
NEXT WEEK AND EXPECT THAT SHOWER ACTIVITY WILL PICK UP THEN AS A
WEAK SURFACE TROUGH EDGES TOWARD THE LOCAL AREA FROM THE WEST.

&&

.AVIATION...BRIEF ISOLD SHRA FOR USVI...TNCM AND TKPK SITES TIL 10Z.
VCSH THRU THE PERIOD. VIS EXPECTED TO REMAIN AT VFR CONDS WITH BRIEF
REDUCTIONS WITHIN -SHRA. WINDS BLW FL100 E 15-25 KT THRU MON. SOME
MOUNTAIN OBSTRUCTIONS IN PUERTO RICO BUT WILL CLEAR FROM THE EAST
BEGINNING AROUND 13/16Z AND AFT 13/22Z AROUND TJMZ.


&&

.MARINE...SEAS REMAIN BELOW SMALL CRAFT ADVISORY CONDITION THROUGH
THE NEW WORK WEEK. WINDS WILL DIMINISH THROUGH MONDAY OF NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 75 86 75 / 50 30 20 20
STT 78 75 80 75 / 30 20 20 30

[cycloneye]

You can go to the PR quake thread at Geology subforum to get more information about the strong 6.4 quake.

viewtopic.php?f=67&t=116119&hilit=&p=2365232#p2365232

[Macrocane]

Central American Cold Surges Thread updated with the observations from the first cold surge of the year: http://www.storm2k.org/phpbb2/viewtopic.php?f=22&t=106879&start=120

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
254 PM AST MON JAN 13 2014

.SYNOPSIS...SURFACE HIGH PRESSURE WILL CONTINUE TO MOVE EAST AS IT
EXITS THE EASTERN UNITED STATES AND THEN ESTABLISH ACROSS THE
CENTRAL ATLANTIC. THIS WILL KEEP MODERATE TO FRESH WINDS FOR THE
NEXT SEVERAL DAYS. UPPER LOW WILL REMAIN OVER THE CENTRAL ATLANTIC
WHILE AN UPPER RIDGE IS SLOWLY DEVELOPING AND WILL BE OVER THE
LOCAL AREA ON WEDNESDAY THROUGH THE END OF THE WEEK. AVAILABLE
MOISTURE WILL BE FAIRLY LIMITED FOR THE NEXT SEVERAL
DAYS.

&&

.DISCUSSION...SCATTERED TO LOCALLY NUMEROUS SHOWERS PASSED ACROSS
THE LOCAL ISLANDS TODAY...MOSTLY IN THE MORNING AND EARLY
AFTERNOON HOURS. IT WAS ALSO BREEZY WITH THE SAN JUAN
INTERNATIONAL AIRPORT REPORTING SUSTAINED WINDS OF OVER 20 MPH.
THIS IS DUE TO THE STRONG HIGH PRESSURE TO THE NORTH OF THE AREA.

SATELLITE IMAGERY INDICATES THAT AN AREA OF DRIER AIR IS MOVING IN
FOR THE REST OF THE AFTERNOON AND ACCORDING TO THE GFS
MODEL...EVEN DRIER AIR IS EXPECTED TO MOVE IN TONIGHT. FOR THAT
REASON ONLY ISOLATED LIGHT SHOWERS...IF ANY...ARE EXPECTED
TONIGHT.

ANOTHER PATCH OF HIGHER MOISTURE IS EXPECTED TO PASS MAINLY TO THE
SOUTH OF PUERTO RICO TOMORROW...MAYBE BRINGING SOME SHOWERS BUT
THE FORECAST SOUNDINGS SUGGEST THAT MOST OF THE MOISTURE WILL BE
LIMITED TO THE LOWER LEVELS OF THE ATMOSPHERE...SO SHOWERS WILL BE SHALLOW.

THIS PATTERN OF BRIEF MOMENTS OF HIGHER MOISTURE ARE EXPECTED FOR
THE NEXT SEVERAL DAYS...BUT FOR THE MOST PART...PRECIPITABLE WATER
VALUES ARE EXPECTED TO BE AT OR BELOW ONE INCH THROUGH THE WORKWEEK.


&&

.AVIATION...MVFR CIGS AT JMZ...JBQ...JPS THRU ABOUT 21Z TODAY. THEN
CLEARING. P6SM SKC ALL OTHER AIRPORTS. EAST WINDS 5-10 KT INCREASING
TO 15G20KT AFTER 14/1330Z.


&&

.MARINE...SEAS REMAIN BELOW SMALL CRAFT ADVISORY CONDITION THROUGH
THE NEW WORK WEEK. WINDS WILL DIMINISH THROUGH MONDAY OF NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 71 81 70 81 / 0 0 0 20
STT 72 84 73 84 / 10 0 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1027 PM AST MON JAN 13 2014

.UPDATE...UPPER LEVEL LOW WITH ASSOCIATED TROUGH ACROSS THE
CENTRAL ATLANTIC WILL AMPLIFY INTO THE EASTERN CARIBBEAN DURING
THE NEXT TWO DAYS OR SO WITH LOCAL ISLANDS REMAINING UNDER ITS
CONVERGENT SIDE. THIS WILL RESULT IN MOISTURE EROSION AND
A FAIR WEATHER PATTERN. RIDGE PATTERN IS THEN EXPECTED TO BUILD
FROM THE WEST AS THE AFOREMENTIONED TROUGH WEAKENS THU-FRI. AS
A RESULT...FAIR WEATHER CONDITIONS WITH A FEW PASSING SHOWERS
EMBEDDED IN THE TRADES WILL CONTINUE THROUGH AT LEAST NEXT WEEK.
MINOR CHANGES WERE INTRODUCED TO FORECAST PACKAGE...JUST TO MATCH
CURRENT CONDITIONS.

[cycloneye]

Good morning. Trade wind showers will continue to move thru PR and VI today.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
523 AM AST TUE JAN 14 2014

.SYNOPSIS...AT UPPER LEVELS...A WEAK UPPER LEVEL TROUGH WILL
TRAVEL THROUGH THE NORTHWEST FLOW TUESDAY NIGHT OVER PUERTO RICO
AND THE U.S. VIRGIN ISLANDS AHEAD OF THE RIDGE . THE RIDGE IS
STILL EXPECTED TO PASS THROUGH FROM THE WEST ON FRIDAY OWING TO
THE TROUGHING MOVING THROUGH FLORIDA AND THE BAHAMA ISLANDS FRIDAY
THROUGH TUESDAY.

AT MID LEVELS...HIGH PRESSURE FROM SOUTH AMERICA TO OVER THE
WINDWARD PASSAGE WILL BE PINCHED BETWEEN A LONG WAVE TROUGH
PASSING TO THE NORTHWEST AND A WEAK LOW THAT DEVELOPS A LITTLE
OVER 800 MILES NORTH NORTHEAST OF SAN JUAN THIS MORNING AND ORBITS
SOUTH AROUND A MUCH STRONGER CUT OFF LOW IN THE CENTRAL
ATLANTIC...COMING TO WITHIN 550 MILES OF SAINT THOMAS BY WEDNESDAY
MORNING. A WEAK BOUNDARY WILL PASS THROUGH THE AREA ON WEDNESDAY
FROM AN OLD FRONT...BUT MOISTURE IS VERY LIMITED UNTIL SUNDAY.

AT LOWER LEVELS...AREAS OF MOISTURE WILL MOVE THROUGH THE PUERTO
RICO...THE U.S. VIRGIN ISLANDS AND THEIR SURROUNDING WATERS WITH
SCATTERED SHOWERS TODAY THROUGH THURSDAY. INTERMITTENT MOISTURE
WILL CONTINUE AS A COL DEVELOPS OVER THE WINDWARD PASSAGE THURSDAY
MORNING AND FLOW OVER THE LOCAL AREA BECOMES MORE EAST SOUTHEAST.
FLOW REMAINS EAST SOUTHEAST AS HIGH PRESSURE MOVES INTO THE
CENTRAL ATLANTIC AND STRENGTHENS SOMEWHAT NEXT WEEK.

&&

.DISCUSSION...A FEW SHOWERS WERE SEEN OVER THE AREA WATERS AND
EASTERN PUERTO RICO OVERNIGHT...BUT LITTLE RAIN FELL. AN AREA OF
SHOWERS NEAR THE LEEWARD ISLANDS WILL MOVE TOWARD THE LOCAL AREA
LATER THIS MORNING AND THERE WILL BE A CHANCE OF SHOWERS OVER THE
U.S. VIRGIN ISLANDS AND EASTERN PUERTO RICO THROUGH THE AFTERNOON.
SOME OF THESE SHOWERS WILL SPREAD INTO WESTERN PUERTO RICO. A MUCH
LARGER AREA OF CLOUDINESS HAS FORMED DURING THE LAST 15 HOURS IN
THE WESTERN TROPICAL ATLANTIC JUST EAST OF THE LEEWARD AND
WINDWARD ISLANDS. SOME OF THIS IS EXPECTED TO CONTRIBUTE TO THE
PASSING SHOWERS ACTIVITY OVER THE LOCAL AREA WEDNESDAY AND
THURSDAY. CURRENTLY THE NAM5 SUGGESTS THAT THE BEST ACTIVITY WILL
BE IN EASTERN PUERTO RICO WEDNESDAY AND WEDNESDAY NIGHT. ALL
MODELS TEND TO DRY OUT AFTER THAT. TRADE WIND FLOW CONTINUES
DURING THE ENTIRE PERIOD...BUT ADDS A SOUTHERLY COMPONENT
BEGINNING WEDNESDAY THAT WILL ALSO SERVE TO HOLD TEMPERATURES A
LITTLE HIGHER OVER THE NORTH COAST...PERHAPS EVEN INTO THE WEEKEND. MOS
GUIDANCE CONTINUES TO BE 3 TO 4 DEGREES TOO COOL OVER THE NORTH
COAST OF PUERTO RICO...BUT OTHER AREAS SEEM OK. 1000-850 MB THICKNESSES
REACH A MINIMUM EARLY WEDNESDAY MORNING THEN GENERALLY INCREASE
THROUGH SUNDAY AND TEMPERATURES TEND TO FOLLOW THAT PATTERN.
NEVERTHELESS EXPECT TEMPERATURES IN THE GREATER SAN JUAN
METROPOLITAN AREA TO CONTINUE TO RUN 2 TO 3 DEGREES ABOVE NORMAL
FOR THE MONTH OF JANUARY AND JUST ABOVE NORMAL EVERYWHERE ELSE.
MOISTURE RETURNS NEXT WEEKEND AND CONTINUES TO RISE THROUGH MID
WEEK NEXT WEEK TO ALMOST 1.7 INCHES OF PRECIPITABLE WATER
ACCORDING TO THE GFS MODEL. SHOWERS WILL INCREASE DURING THIS PERIOD.

&&

.AVIATION...BRF ISOLD VCSH ACROSS TIST AND TISX FROM AT LEAST
09-12Z. COND LESS THAN VFR HIGHLY UNLIKELY...BUT SOME MOUNTAIN
OBSCURATIONS ARE EXPECTED NOW THROUGH 14/23Z. WINDS BLO FL100 E MAINLY
10-20 KT.


&&

.MARINE...AREAS BEHIND PUERTO RICO IN THE WEST ARE PROTECTED...OTHERWISE
SMALL CRAFT WILL NEED TO EXERCISE CAUTION IN THE LOCAL WATERS.
SEAS OF UP TO 6 FT WILL PERSIST THROUGH WEDNESDAY AND THEN
DIMINISH A LITTLE.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 75 83 75 / 40 30 20 30
STT 85 77 84 77 / 40 30 40 50

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
248 PM AST TUE JAN 14 2014

.SYNOPSIS...SURFACE HIGH PRESSURE TO THE NORTH NORTHEAST OF THE
LOCAL AREA WILL CONTINUE TO MOVE EAST AND THEN ESTABLISH ACROSS
THE CENTRAL ATLANTIC BY THURSDAY. THIS WILL KEEP MODERATE TO FRESH WINDS
UNTIL THEN. UPPER LOW WILL REMAIN OVER THE CENTRAL
ATLANTIC WHILE SLOWLY WEAKENING UNTIL IT DISSIPATES ON THURSDAY
WHEN THE SURFACE HIGH ESTABLISHES IN THAT AREA. AVAILABLE MOISTURE
WILL START TO DIMINISH TONIGHT AND IT WILL BE FAIRLY LIMITED TO
THE LOWER LEVELS OF THE ATMOSPHERE FOR THE NEXT SEVERAL DAYS.

&&

.DISCUSSION...SCATTERED TO LOCALLY NUMEROUS SHOWERS PASSED ACROSS
THE LOCAL ISLANDS TODAY...MOSTLY ACROSS THE USVI AND EASTERN PR IN
THE MORNING AND EARLY AFTERNOON. THESE SHOWERS WILL CONTINUE TO
MOVE WEST AND AFFECT PORTIONS OF CENTRAL AND WESTERN PR LATER IN
THE AFTERNOON. IT WAS ALSO BREEZY WITH THE SAN JUAN INTERNATIONAL
AIRPORT REPORTING SUSTAINED WINDS OF OVER 20 MPH. THIS IS DUE TO
THE STRONG HIGH PRESSURE TO THE NORTH OF THE AREA.

SATELLITE IMAGERY INDICATES THAT AN AREA OF DRIER AIR IS MOVING IN
FOR THIS EVENING AND ACCORDING TO THE GFS
MODEL...RELATIVELY DRY AIR IS EXPECTED TO BE OVER THE AREA FOR THE
REST OF THE WORKWEEK. FOR THAT REASON ISOLATED TO LOCALLY
SCATTERED SHOWERS...ARE EXPECTED FOR THE NEXT FEW DAYS. IN
ADDITION...MOST OF THE AVAILABLE MOISTURE WILL BE LIMITED TO THE
LOWER LEVELS OF THE ATMOSPHERE...SO SHOWERS WILL BE LIGHT TO
MODERATE.

FOR NEXT WEEK...GFS MODEL SUGGESTS THAT A FRONTAL BOUNDARY WILL
STALL TO THE NORTH OF THE LOCAL AREA...KEEPING US UNDER AN AREA
WITH SIGNIFICANTLY MORE MOISTURE THAT WHAT WE HAVE OBSERVED FOR
THE LAST FEW DAYS. AN INCREASE IN CLOUD COVER AND SHOWER ACTIVITY
IS POSSIBLE FOR THE EARLY PART OF NEXT WEEK IF THE GFS MODEL IS CORRECT.

&&

.AVIATION...SCT-BKN CLDS MAINLY BTW FL020-FL070 WITH EMBEDDED PASSING
-SHRA/SHRA WILL CONTINUE TO AFFECT FLYING AREA TIL 14/23Z. HOWEVER
VFR CONDS IS FORECAST TO PREVAIL AT ALL TAF SITES NXT 24 HOURS.
L/LVL WNDS MAINLY FM THE E AT 10-20 KTS BLO FL200 BCMG FM N AND INCR
W/HT ABOVE.NO OTHER SIG WX OPERATIONAL IMPACTS AT THIS TIME.


&&

.MARINE...BUOY DATA AND MARINE OBSERVATIONS INDICATE THAT OVERALL
TRADE WINDS CONTINUE AT 21 KNOTS OR LESS WITH SEAS OF 6 FEET OR
LESS...SMALL CRAFT OPERATORS SHOULD THEREFORE CONTINUE TO EXERCISE
CAUTION ACROSS MOST OF THE LOCAL WATERS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 71 81 71 80 / 30 20 30 10
STT 70 83 73 84 / 30 40 50 20

[Macrocane]

Coldest air of the season so far is approaching Central America, some models are forecasting the coldest temperatures since at least 2010. Look at the anomalies expected:

[cycloneye]

Good morning. Trade wind showers will continue to move thru PR and VI today.



AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
449 AM AST WED JAN 15 2014

.SYNOPSIS....RIDGE PATTERN ALOFT WILL BUILD FROM THE WEST OVER THE
NEXT FEW DAYS AS MID TO UPPER LEVEL LOW AND ASSOCIATED TROUGH
ACROSS THE CENTRAL ATLANTIC INTO THE EASTERN CARIBBEAN WEAKENS.
PATCHES OF LOW LEVEL MOISTURE WILL MOVE ACROSS THE LOCAL AREA FROM
TIME TO TIME.

&&

.DISCUSSION...FRAGMENT OF LOW LEVEL MOISTURE HAS BEEN MOVING
ACROSS THE LOCAL AREA OVERNIGHT...WITH SOME CLOUDINESS SEEN ON
SATELITE IMAGES. HOWEVER...DOPPLER RADAR ONLY DETECTED FEW LIGHT
PASSING SHOWERS ASSOCIATED WITH IT. LATEST SATELITE IMAGES AS
WELL AS LATEST TPW PRODUCT FROM CIMMS SHOWS VERY DRY AIR AT LOW
LEVEL OF THE ATMOSPHERE WILL ENCOMPASS THE REGION TODAY.
PRECIPITABLE WATER VALUES ARE EXPECTED TO DROP BELOW 1.0 INCHES
TODAY...WHICH WILL LIMIT CONSIDERABLY THE CHANCES FOR SHOWERS.

RIDGE PATTERN ALOFT WILL BUILD FROM THE WEST OVER THE
NEXT FEW DAYS AS MID TO UPPER LEVEL LOW AND ASSOCIATED TROUGH
ACROSS THE CENTRAL ATLANTIC INTO THE EASTERN CARIBBEAN WEAKENS.
THIS WEATHER PATTERN WILL MAINTAIN RELATIVELY DRY CONDITION ACROSS
THE REGION...WITH PLEASANT TEMPERATURES ACROSS MOST OF THE LOCAL
ISLANDS.

IS NOT UNTIL EARLY NEXT WEEK...AN INCREASE IN LOW LEVEL MOISTURE
IS EXPECTED...AS THE AFOREMENTIONED UPPER LEVEL RIDGE WEAKENS AND
AN UPPER LEVEL TROUGH DEVELOPS OVER THE WESTERN
ATLANTIC...INCREASING THE CHANCES FOR SHOWERS OVER THE REGION. AT
THIS TIME...NO SIGNIFICANT WEATHER EVENTS ARE FORECAST TO AFFECT
THE LOCAL REGION IN THE NEAR FUTURE.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL AT ALL TAF SITES
THROUGH THE FORECAST PERIOD. HOWEVER...PATCHES OF SC CLOUDS BETWEEN
FL040-FL060 WILL CONTINUE TO MOVE WESTWARD ACROSS THE FLYING AREA...
PRODUCING SCT-BKN SKIES AND -SHRA. EASTERLY WINDS AT 10-20 KT ARE
EXPECTED BELOW FL050.

&&

.MARINE...SMALL BOAT OPERATORS SHOULD EXERCISE CAUTION AS WINDS OF
UP TO 20 KNOTS AND SEAS OF UP TO 6 FEET CONTINUE TO PREVAIL ACROSS
THE LOCAL WATERS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 82 72 80 72 / 30 30 20 20
STT 84 72 84 71 / 40 30 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
259 PM AST WED JAN 15 2014

.SYNOPSIS...RIDGE PATTERN IN THE UPPER LEVELS WILL CONTINUE TO BUILD
TO THE WEST OF THE LOCAL AREA FOR NEXT FEW DAYS AS MID TO UPPER
LEVEL LOW AND ASSOCIATED TROUGH ACROSS THE CENTRAL ATLANTIC INTO
THE EASTERN CARIBBEAN WEAKENS. PATCHES OF LOW LEVEL MOISTURE WILL
MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME...WHICH WILL CONTINUE
TO CAUSE ISOLATED TO SCATTERED LIGHT PASSING SHOWERS.

&&

.DISCUSSION...A FEW SHOWERS WERE OBSERVED ACROSS THE LOCAL WATERS
IN THE MORNING BUT ALMOST NO RAIN WAS OBSERVED OVER LAND.
CLOUDINESS INCREASED DURING THE DAY DUE TO OROGRAPHIC
LIFTING BUT AGAIN...NO SHOWER ACTIVITY WAS OBSERVED.

RELATIVELY DRY AIR IS EXPECTED TO CONTINUE MOVING OVER THE AREA
FOR THE REST OF THE WORKWEEK WITH A FEW PATCHES OF MOISTURE. FOR THAT
REASON...ISOLATED TO LOCALLY SCATTERED SHOWERS ARE POSSIBLE FOR THE
NEXT FEW DAYS. IN ADDITION...MOST OF THE AVAILABLE MOISTURE WILL
BE LIMITED TO THE LOWER LEVELS OF THE ATMOSPHERE...SO SHOWERS WILL
BE LIGHT TO MODERATE.

FOR NEXT WEEK...GFS MODEL SUGGESTS THAT A FRONTAL BOUNDARY WILL
STALL TO THE NORTH OF THE LOCAL AREA...KEEPING US UNDER AN AREA
WITH SIGNIFICANTLY MORE MOISTURE THAT WHAT WE HAVE OBSERVED FOR
THE LAST FEW DAYS. AN INCREASE IN CLOUD COVER AND SHOWER ACTIVITY
IS POSSIBLE FOR THE EARLY PART OF NEXT WEEK.


&&

.AVIATION...VFR CONDS ARE EXPECTED TO PREVAIL AT ALL TAF SITES
THROUGH THE FCST PRD. HOWEVER...PATCHES OF SHALLOW CLD LYR MAINLY
BTW FL020-FL070 WILL CONTINUE TO MOVE WESTWARD ACROSS THE FLYING
AREA THROUGH 16/00Z. FEW -SHRA/SHRA MAY ACCOMPANY THE PASSING CLD
LYRS IN THE PREVAILING EASTERLY TRADE WINDS. L/LVL WND FM E AT
10-20 KT BLO FL100...THEN BACKING BCMG NORTHERLY AND INCR W/HT ABV
FL150. NO SIG OPERATIONAL WX IMPACTS AT THIS TIME.

&&

.MARINE...WINDS AND SEAS CONTINUE AT 20 KNOTS OR LESS AND SEAS OF
6 FEET OR LESS ACROSS THE LOCAL WATERS. SMALL CRAFT OPERATORS
SHOULD CONTINUE TO EXERCISE CAUTION ACROSS MOST OF THE OFFSHORE
WATERS AND LOCAL PASSAGES TODAY DUE TO SLIGHT WIND THROUGH TONIGHT.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 81 72 80 / 30 20 20 20
STT 72 83 73 85 / 30 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1028 PM AST WED JAN 15 2014

.UPDATE...A FEW CHANGES WERE INTRODUCED TO THE FORECAST PACKAGE
JUST TO MATCH CURRENT CONDITIONS...BUT OVERALL FORECAST ON TRACK.
RIDGE PATTERN ALOFT WILL CONTINUE TO BUILD FROM THE WEST AS MID
TO UPPER LEVEL LOW AND ASSOCIATED TROUGH ACROSS THE CENTRAL
ATLANTIC INTO THE EASTERN CARIBBEAN WEAKENS. THIS WILL PROMOTE
STABLE WEATHER CONDITIONS OVER THE AREA. HOWEVER...LOW LEVEL
MOISTURE CONFINED BELOW 700MB WILL CONTINUE TO MOVE ACROSS THE
LOCAL ISLANDS FROM TIME TO TIME BRINGING SOME CLOUD CLUSTERS AS
WELL AS A FEW PASSING SHOWERS MAINLY ACROSS PORTIONS OF EASTERN
PUERTO RICO AND THE USVI.

RIDGE ALOFT WILL ERODE EARLY NEXT WEEK AS A DEEP POLAR TROUGH
MOVES ACROSS THE WESTERN ATLANTIC...ALLOWING BETTER MOISTURE
ADVECTION ACROSS THE AREA.

&&

.AVIATION...MOSTLY VFR CONDITIONS ARE EXPECTED TO PREVAIL ACROSS THE
LOCAL FLYING AREA THROUGH THE FORECAST PERIOD. HOWEVER...PATCHES OF
SHALLOW MOISTURE WILL CONTINUE TO MOVE WESTWARD ACROSS THE FLYING
AREA THROUGH 16/12Z. FEW -SHRA/SHRA EMBEDDED IN THE TRADE WIND FLOW
MAY ALSO AFFECT SOME OF THE TERMINALS. LATEST TJSJ 16/00 SOUNDING
INDICATED AN EASTERLY WIND FLOW UP TO 20 KNOTS FROM THE SURFACE TO
15K FEET...BECOMING FROM THE NORTH AND STRONGER ALOFT.

&&

.MARINE...NO CHANGE TO PREVIOUS DISCUSSION. SMALL BOAT OPERATORS
SHOULD EXERCISE CAUTION AS WINDS OF UP TO 20 KNOTS AND SEAS OF UP
TO 6 FEET CONTINUE TO PREVAIL ACROSS THE LOCAL WATERS.

[Macrocane]

Strong cold front has reached the area. Winds began to pick up in the afternoon and now very strong wind gusts have been blowing in northern Central America, tomorrow morning will be very cold.


...SPECIAL FEATURE...
GULF OF TEHUANTEPEC...COOL DENSE AIR IN THE WAKE OF A COLD FRONT
OVER THE GULF OF MEXICO IS FUNNELING THROUGH THE CHIVELA PASS
ACROSS THE GULF OF TEHUANTEPEC. A REINFORCING COLD FRONT ACROSS
THE GULF OF MEXICO HAS REACHED THE BAY OF CAMPECHE. THIS HAS
FURTHER INCREASE WINDS FUNNELING THROUGH THE CHIVELA PASS...AND
THE GALE FORCE WINDS IN THE GULF OF TEHUANTEPEC HAVE INCREASED
TO STORM FORCE (OR 50 KT). SEAS OF WILL BUILD AS HIGH AS 24 FT
OVERNIGHT. WINDS WILL DIMINISH BELOW STORM FORCE BY LATE THU
MORNING...WITH GALES EXPECTED TO CONTINUE THROUGH SATURDAY
MORNING.

GULF OF PAPAGAYO...STRONG HIGH PRES BUILDING OVER N AMERICA AND
THE GULF OF MEXICO BEHIND A PAIR OF COLD FRONTS WILL SUPPORT
STRONG GAP WIND FLOW THROUGH THE GULF OF PAPAGAYO AND GULF OF
FONSECA BEGINNING OVERNIGHT...WITH MAXIMUM WINDS TO AROUND 30 KT
EXPECTED EARLY THURSDAY THROUGH FRIDAY MORNING AS A GULF OF
MEXICO COLD FRONT MOVES SE THROUGH THE WESTERN CARIBBEAN.

[cycloneye]

Good morning. Only a few showers are expected today in PR and VI.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
434 AM AST THU JAN 16 2014

.SYNOPSIS...RIDGE PATTERN ALOFT WILL CONTINUE TO BUILD FROM THE WEST
AS MID TO UPPER LEVEL LOW AND ASSOCIATED TROUGH ACROSS THE CENTRAL
ATLANTIC INTO THE EASTERN CARIBBEAN WEAKENS. THIS SCENARIO WILL
PROMOTE STABLE WEATHER CONDITIONS OVER THE AREA. PATCHES OF LOW
LEVEL MOISTURE WILL CONTINUE TO AFFECT THE LOCAL REGION.

&&

.DISCUSSION...SCATTERED SHOWERS WERE NOTED MAINLY OVER THE
COASTAL WATERS OVERNIGHT. VERY LITTLE SHOWER ACTIVITY WAS OBSERVED
OVER THE LOCAL ISLANDS. LIGHT WINDS AT THE SURFACE...COMBINED WITH
LITTLE CLOUD COVERAGE...CONTRIBUTED TO MINIMUM TEMPERATURES IN THE
MOUNTAINS IN THE 50S AND LOW 60S. PLEASANT TEMPERATURES ARE
EXPECTED ONCE AGAIN TODAY AND TONIGHT...AS NO CHANGES IN THE CURRENT
WEATHER PATTERN IS EXPECTED.

WEATHER CONDITIONS CONTINUE UNCHANGED. RIDGE PATTERN ALOFT WILL
CONTINUE TO BUILD FROM THE WEST AS MID TO UPPER LEVEL LOW AND
ASSOCIATED TROUGH ACROSS THE CENTRAL ATLANTIC INTO THE EASTERN
CARIBBEAN WEAKENS. THIS SCENARIO WILL PROMOTE STABLE WEATHER
CONDITIONS OVER THE AREA. HOWEVER...PATCHES OF LOW LEVEL MOISTURE
WILL CONTINUE TO AFFECT THE LOCAL REGION FROM TIME TO
TIME...BRINGING WITH IT SOME SHOWERS OVER THE REGION. NO
SIGNIFICANT RAINFALL ACCUMULATION ARE EXPECTED.

IN THE LONG TERM...BY LATE NEXT WEEK...A FRONTAL BOUNDARY IS
EXPECTED TO EXIT THE EASTERN U.S. COAST...AND IS FORECAST BY
COMPUTER MODELS TO APPROACH THE REGION. IF THIS SCENARIO
VERIFIES..AN INCREASE IN CLOUDINESS WITH SHOWERS WILL BE
EXPECTED...MAINLY ALONG THE NORTH COAST OF PUERTO RICO.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL AT ALL TAF SITES
DURING THE NEXT 24 HOURS. FEW-SCT CLOUDS AND A FEW PASSING SHOWERS
CAN BE EXPECTED ACROSS THE FLYING AREA. VCSH POSSIBLE OVER THE USVI
AND THE LEEWARD ISLAND TERMINALS AS WELL AS TJSJ. E TO ESE WINDS AT
15 TO 25 KNOTS JUST ABV SURFACE TO 5K FEET.

&&

.MARINE...SMALL BOAT OPERATORS SHOULD EXERCISE CAUTION AS WINDS OF
UP TO 20 KNOTS AND SEAS OF UP TO 6 FEET CONTINUE TO PREVAIL ACROSS
THE LOCAL WATERS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 81 72 81 72 / 40 20 20 10
STT 83 70 85 72 / 40 30 20 10

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
255 PM AST THU JAN 16 2014

.SYNOPSIS...MID TO UPPER LEVEL HIGH PRESSURE RIDGE WILL REMAIN IN
PLACE AND CONTINUE TO DOMINATE THE LOCAL WEATHER PATTERN DURING THE
NEXT SEVERAL DAYS. AS A RESULT...A FAIRLY STRONG SUBSIDENCE CAP WILL
BE MAINTAINED AND THUS LIMIT CONVECTIVE DEVELOPMENT OVER THE REST
FOR THE WORK WEEK AS THE SHALLOW MOISTURE TO REMAIN TRAPPED BELOW
800 MILLIBARS AS INDICATED BY LATEST UPPER AIR SOUNDINGS AND
SATELLITE IMAGERY. FURTHER NORTHEAST ACROSS THE OPEN TROPICAL
ATLANTIC...IS A A TUTT LOW SUPPORTED BY AN INDUCED SURFACE TROUGH.
THESE FEATURES ARE FORECAST TO RETROGRESS WESTWARD TOWARDS THE LESSER
ANTILLES BY THE UPCOMING WEEKEND...AND THEREFORE EXPECT THE RIDGE
ALOFT TO WEAKEN ACROSS THE NORTHEASTERN CARIBBEAN.MEANWHILE...
STRONG SURFACE HIGH PRESSURE WAS LOCATED ACROSS THE NORTH CENTRAL
ATLANTIC AND CONTINUE TO RIDGE SOUTHWARDS ACROSS THE REGION. THIS
WILL MAINTAIN MODERATE EASTERLY TRADES ACROSS THE AREA THROUGH FRIDAY.
THE TRADE WINDS WILL HOWEVER DIMINISH OVER THE NEXT FEW DAYS AS THE
LOCAL PRESSURE GRADIENT WEAKENS. THE SURFACE TROUGH IS ALSO FORECAST
TO WEAKEN AND EXPECTED TO MERGE WITH AN OLD FRONTAL TROUGH WHICH
WILL REPOSITION NORTHWEST OF THE REGION BY SUNDAY AND MONDAY.

&&

.DISCUSSION...PATCHES OF SHALLOW TRADE WIND MOISTURE WILL MOVE ACROSS
THE REGION FROM TIME TO TIME...AS THE HIGH PRESSURE RIDGE WILL
CONTINUE TO INFLUENCE THE LOCAL WEATHER PATTERN AND LIMIT CONVECTION
ACROSS THE ISLANDS AND LOCAL WATERS. BY FRIDAY HOWEVER THE SURFACE
RIDGE IS EXPECTED TO ERODE AS WELL AS LOCAL PRESSURE GRADIENT.
THIS WILL ALLOW FOR MORE SEA BREEZE VARIATIONS AND LOW LEVEL MOISTURE
CONVERGENCE. IN ADDITION...THE LOW LEVEL EASTERLY TRADE WILL BECOME
MORE SOUTHEAST DURING THE REST OF THE WEEK AND INTO THE WEEKEND
AND ALSO ALLOW FOR SLIGHT INCREASE IN LOW LEVEL TROPICAL MOISTURE.
THE AVAILABLE SHALLOW MOISTURE ALONG WITH LOCAL TERRAIN EFFECTS
AND SEA BREEZE INFLUENCES WILL LEAD TO ISOLATED TO SCATTERED DAYTIME
CONVECTION ACROSS PARTS OF THE ISLANDS. ACTIVITY SHOULD HOWEVER BE
FOCUSED MAINLY OVER THE NORTH CENTRAL AND NORTHWEST SECTIONS OF
PUERTO RICO...COMPARED TO THE ADVECTIVE SHOWER ACTIVITY WHICH HAD
BEEN AFFECTING PARTS OF EASTERN PUERTO RICO AND THE ADJACENT
ISLANDS MAINLY DURING THE OVERNIGHT AND EARLY MORNING HOURS IN
RECENT DAYS. NO OTHER SIGNIFICANT WEATHER FEATURE IS FORECAST AT
THIS TIME...WITH OVERALL FAIR WEATHER CONDITIONS STILL EXPECTED
TO PREVAIL FOR THE UPCOMING WEEKEND.


&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS THE LOCAL TERMINALS FOR
THE NEXT 24 HOURS WITH PASSING SHRA ACROSS THE AREA THROUGH THE PERIOD.
ESE WINDS AT 10 TO 15 KTS EXPECTED TO PREVAIL UNTIL AROUND 16/23Z.
THEREAFTER...WINDS ARE EXPECTED TO DIMINISH TO AROUND 5-10 KTS
OVERNIGHT. AFTER 17/13Z...WINDS ONCE AGAIN EXPECTED TO BE MAINLY
FROM THE ESE WITH SEA BREEZE VARIATIONS AT ABOUT 10 KTS.


&&

.MARINE...WINDS AND SEAS CONTINUE TO DIMINISH ACROSS THE LOCAL
WATERS AS THE LOCAL PRESSURE GRADIENT LOOSENS ACROSS THE REGION.
SMALL CRAFT OPERATORS SHOULD HOWEVER EXERCISE CAUTION TONIGHT.
PLEASE REFER TO THE LATEST COASTAL WATERS FORECAST FOR LATEST
MARINE CONDITIONS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 82 72 81 / 20 20 10 10
STT 73 85 74 85 / 30 20 10 20

[Macrocane]

COLDEST TEMPERATURES OF THE SEASON IN CENTRAL AMERICA SO FAR

It has been a cold day today in most of Central America, we had the coldest temperatures in years in some locations. These are the minimum temperatures registered on January 16, 2014 in the region:

Belize city, Belize 16.6°C (61.9°F) Coldest since March 4, 2013
Guatemala city, Guatemala 8.8°C (47.8°F) Coldest since December 28, 2010
Quetzaltenango, Guatemala -0.5°C (31.1°F)
Zacapa, Guatemala 14.1°C (57.0°F) Coldest since March 4, 2013
San Salvador, El Salvador 14.4°C (57.9°F) Coldest since January 8, 2011
Las Pilas, El Salvador 4.5°C (40.1°F) Coldest since March 4, 2013
San Miguel, El Salvador 21.5°C (70.7°F)
Tegucigalpa, Honduras 12°C (54°F)
La Esperanza, Honduras 6°C (43°F)
Managua, Nicaragua 23°C (73°F)
Jinotega, Nicaragua 15°C (59°F) Coldest since March 4, 2013
San Jose, Costa Rica 16.6°C (61.9°F)
Irazu volcano, Costa Rica 5.1°C (41.2°F)
Liberia, Costa Rica 22.0°C (71.6°F)
Panama city, Panama 23.4°C (74.1°F)
Baru volcano, Panama 16.4°C (61.5°F)

[cycloneye]

Good morning. Only a few showers are expected today in PR and VI with mainly good weather prevailing this weekend.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
538 AM AST FRI JAN 17 2014

.SYNOPSIS...UPPER LEVEL RIDGE WILL REMAIN ANCHORED ACROSS THE
NORTHEAST CARIBBEAN THROUGH MID NEXT WEEK. PATCHES OF LOW LEVEL
MOISTURE WILL CONTINUE TO MOVE ACROSS THE AREA FROM TIME TO TIME.

&&

.DISCUSSION...DRY CONDITIONS HAVE PREVAILED ACROSS PUERTO RICO AND
THE U.S. VIRGIN ISLANDS OVERNIGHT AND EARLY THIS MORNING. ONLY LIGHT
PASSING SHOWERS HAVE BEEN OBSERVED OVER THE LOCAL WATERS. WEATHER
CONDITIONS WILL REMAIN DRY THROUGH THE UPCOMING WEEKEND...AS AN
UPPER LEVEL RIDGE REMAINS OVER THE LOCAL AREA.

FRONTAL BOUNDARY LOCATED OVER THE BAHAMAS...WILL INDUCE A MORE
SOUTHEASTERLY WIND FLOW ACROSS THE LOCAL AREA. THIS WILL ALLOW FOR
MORE SEA BREEZE VARIATIONS AND LOW LEVEL MOISTURE CONVERGENCE.
HOWEVER...NOT SIGNIFICANT OR WIDESPREAD PRECIPITATION IS EXPECTED.

PATCHES OF LOW LEVEL MOISTURE WILL CONTINUE TO AFFECT THE LOCAL
REGION FROM TIME TO TIME. IN THE LONG TERM...MODELS INDICATED
PRECIPITABLE WATER VALUES WILL INCREASE SLIGHTLY MID NEXT WEEK AS
SURFACE HIGH PRESSURE WEAKENS AND AN EAST SOUTHEASTERLY WINDS BRINGS
WITH IT TROPICAL MOISTURE TO THE AREA.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL AT ALL TAF SITES
DURING THE FORECAST PERIOD. FEW-SCT CLOUDS AND A FEW PASSING SHOWERS
ARE POSSIBLE ACROSS THE USVI AND EASTERN PR. HOWEVER...NO
SIGNIFICANT AVIATION HAZARD IS EXPECTED AT THIS TIME. ESE WINDS AT
10-20 KNOTS WILL PREVAIL MOST OF THE DAY FM SFC TO 5K FEET.

&&

.MARINE...WINDS AND SEAS CONTINUE TO DIMINISH ACROSS THE LOCAL
WATERS AS THE LOCAL PRESSURE GRADIENT LOOSENS ACROSS THE REGION.
SMALL CRAFT OPERATORS SHOULD HOWEVER EXERCISE CAUTION TODAY ACROSS
MOST COASTAL WATERS. PLEASE REFER TO THE LATEST COASTAL WATERS FORECAST
FOR LATEST MARINE CONDITIONS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 82 72 83 73 / 30 10 10 10
STT 84 73 85 75 / 30 10 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
212 PM AST FRI JAN 17 2014

.SYNOPSIS...HIGH PRESSURE RIDGE ALOFT WILL REMAIN IN PLACE AND
CONTROL THE LOCAL WEATHER PATTERN THROUGH AT LEAST SATURDAY. BY
SUNDAY HOWEVER IT IS TO GRADUALLY ERODE AS LONG WAVE POLAR TROUGH
MOVES EASTWARD INTO THE WESTERN ATLANTIC. AS A RESULT THE PRESENT
SUBSIDENCE CAP IS EXPECTED TO WEAKEN AND ALLOW FOR AT LEAST SOME
ISOLATED DAYTIME CONVECTION OVER THE NEXT FEW DAYS. IN THE LOW
LEVELS PRESSURE GRADIENT ACROSS THE REGION CONTINUED TO LOOSEN
AS THE SURFACE HIGH PRESSURE RIDGE ACROSS THE NORTHEASTERN CARIBBEAN
SHIFTED FURTHER EAST IN RESPONSE TO THE FRONTAL TROUGH ENTERING THE
WESTERN ATLANTIC AND RIDING THE WESTERN PERIPHERY OF THE ATLANTIC
HIGH. LATEST SATELLITE IMAGERY SHOWED FRAGMENTS OF SHALLOW LOW LEVEL
CLOUDS MOVING WEST NORTHWEST ACROSS THE FORECAST AREA. WELL NORTHEAST
OF THE AREA...A TUTT LOW MEANDERED ACROSS THE TROPICAL ATLANTIC...WHILE
A WEAK INDUCED LOW LEVEL TROUGH CONTINUED TO DETACH ITSELF FROM UPPER
LOW AND SHIFT FURTHER WEST TOWARDS THE LESSER ANTILLES. THE SURFACE
TROUGH IS EXPECTED TO CONTINUE WEAKENING AND EVENTUALLY MERGE WITH
THE WEAKENING FRONTAL TROUGH WHICH IS EXPECTED TO STALL NORTHWEST
OF THE REGION BY SUNDAY AND MONDAY. THIS WILL ALLOW FOR FAIRLY LIGHT
EASTERLY TRADE WINDS ACROSS THE NORTHEASTERN CARIBBEAN.

&&

.DISCUSSION...SATELITE IMAGERY AS WELL AS DOPPLER WEATHER RADAR
SHOWED FRAGMENTS OF TRADE WIND MOISTURE BEING TRANSPORTED BY THE
PREVAILING EASTERLIES ACROSS THE REGION. ONLY A FEW PASSING SHOWERS
WERE NOTED AFFECTING PARTS OF THE NORTHERN LEEWARDS AS WELL AS IN
ISOLATED AREAS OF EASTERN PUERTO RICO. FOR THE REST OF THE AFTERNOON
AND OVER THE UPCOMING LONG WEEKEND...EXPECT A SIMILAR WEATHER
PATTERN AS RECENT DAYS. HOWEVER...THE LOOSENING OF THE LOCAL PRESSURE
GRADIENT... EXPECT MORE SEA BREEZE INTERACTION AND LOCAL EFFECTS TO
AID IN THE DEVELOPMENT OF DAYTIME CONVECTION. THE LOW LEVEL EASTERLY
TRADE WINDS HAVE BECOME MORE SOUTHEASTERLY AND WILL CONTIUE INTO
THE WEEKEND. THIS SHOULD ALLOW FOR A SLIGHT INCREASE IN LOW LEVEL
TROPICAL MOISTURE ADVECTION. ACTIVITY SHOULD HOWEVER BE FOCUSED
MAINLY OVER THE NORTH CENTRAL AND WEST SECTIONS OF PUERTO RICO
DURING THE AFTERNOON HOURS. SOME EARLY MORNING PASSING SHOWERS ARE
EXPECTED TO BRUSH PARTS OF THE EAST AND SOUTHEAST COASTAL AREAS
EACH DAY. NO OTHER SIGNIFICANT WEATHER FEATURE IS FORECAST AT THIS
TIME...WITH OVERALL FAIR WEATHER CONDITIONS EXPECTED FOR MOST OF
THE WEEKEND.

&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS THE LOCAL TERMINALS FOR
THE NEXT 24 HOURS. ESE WINDS AT 10 TO 15 KTS EXPECTED TO PREVAIL
UNTIL AROUND 17/22Z. THEREAFTER...WINDS ARE EXPECTED TO DIMINISH TO
AROUND 5-10 KTS OVERNIGHT. AFTER 18/13Z...WINDS ONCE AGAIN EXPECTED
TO BE MAINLY FROM THE ESE WITH SEA BREEZE VARIATIONS AT ABOUT 10
KTS.

&&

.MARINE...SEAS CONTINUE TO IMPROVE AND WERE NOW UNDER 6 FEET. HOWEVER
WINDS ACROSS THE LOCAL WATERS CONTINUE AT 20 KNOTS OR LESS. FOR
THIS REASON SMALL CRAFT OPERATORS ARE URGED TO EXERCISE CAUTION
ACROSS MOST OF THE LOCAL WATERS OVERNIGHT THROUGH SATURDAY MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 83 73 82 / 10 10 10 10
STT 73 85 75 85 / 10 20 20 20

[cycloneye]

Good morning. Goud weather will prevail this weekend in PR and VI.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
535 AM AST SAT JAN 18 2014

.SYNOPSIS...MID TO UPPER LEVEL RIDGE WILL HOLD THROUGH THE WEEKEND...
BUT IT IS EXPECTED TO COLLAPSE AS A DEEP POLAR TROUGH MOVES NORTH
OF THE ISLANDS EARLY NEXT WEEK. MEANWHILE...THE RIDGE ALOFT WILL
CONTINUE TO SUSTAIN A SUBSIDENCE PATTERN ACROSS THE FORECAST AREA...
LEADING TO GENERALLY STABLE CONDITIONS ACROSS THE LOCAL ISLANDS DURING
THE WEEKEND.

&&

.DISCUSSION...WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL TROUGH DOMINATING
THE WEATHER CONDITIONS ACROSS THE EASTERN AND CENTRAL CARIBBEAN. THE
RIDGE ALOFT HAVE MAINTAINED A TRANQUIL CONDITIONS ACROSS THE FORECAST
AREA SINCE MIDNIGHT...AND THIS QUIET PATTERN IS EXPECTED TO CONTINUE
THE REST OF THE WEEKEND. IN FACT...SATELLITE DERIVED PWAT ANALYSIS SHOWS
AN AREA OF 20-30 PERCENT BELOW NORMAL MOISTURE UPSTREAM OF PUERTO RICO
AND THE VIRGIN ISLANDS. RECENT GUIDANCE CONTINUES TO SUGGEST A GENERALLY
DRIER AIR OVER THE LOCAL AREA THROUGH THE END OF THE WEEKEND THAT SHOULD
LIMIT THE SHOWER ACTIVITY. AS A RESULT...EXPECT MOSTLY SUNNY CONDITIONS
ACROSS MOST OF THE ISLANDS WITH A FEW TRADE WIND SHOWERS OVER THE WINDWARD
SIDE OF THE ISLANDS.

FOR EARLY NEXT WEEK...MODELS ARE SUGGESTING A WEAK TROUGH MOVING
ACROSS THE ISLANDS BETWEEN MONDAY AND TUESDAY. THIS SURFACE TROUGH
WILL BRING ADDITIONAL MOISTURE TO THE REGION...RESULTING IN A FEW
ROUNDS OF SCATTERED SHOWERS ACROSS FORECAST AREA. THIS PERTURBATION
WILL ALSO ENHANCE THE SEA BREEZE CONVERGENCE ACROSS WESTERN PUERTO
RICO...LEADING TO HEAVY RAINFALL MAINLY IN THE AFTERNOON.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL ACROSS ALL TAF
SITES THROUGH AT LEAST 18/22Z. SURFACE WINDS WILL BE MAINLY EAST
SOUTHEAST AT 10 TO 15 KTS.

&&

.MARINE...THE CURRENT NORTHEAST SWELL WILL CONTINUE TO PRODUCE
WAVE HEIGHTS UP TO 6 FEET ACROSS THE ATLANTIC WATERS AN CARIBBEAN
PASS SAGE TODAY. THIS SWELL WILL LOWER GRADUALLY TONIGHT AND SUNDAY.
ANOTHER...SLIGHTLY SMALLER NORTHWEST SWELL IS EXPECTED TO ARRIVE ON
MONDAY. OVERALL...EXPECT SEAS OF 4-6 FEET THROUGH TONIGHT...GRADUALLY
SUBSIDING TO 3-5 FEET FROM SUNDAY UNTIL AT LEAST TUESDAY. SMALL CRAFT
OPERATORS SHOULD EXERCISE CAUTION TODAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 85 76 86 74 / 10 10 10 20
STT 86 77 85 78 / 20 20 20 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
321 PM AST SAT JAN 18 2014

.SYNOPSIS...AT UPPER LEVELS...THE HIGH PRESSURE RIDGE EXTENDING
NORTH NORTHEAST ACROSS THE LEEWARD ISLANDS WILL WEAKEN AS IT
DRIFTS EASTWARD. SHORT WAVES TRAVELING THROUGH THE LONG WAVE
TROUGH WHICH IS OVER THE NORTHEASTERN UNITED STATES WILL LIGHTLY
BRUSH PUERTO RICO AND THE U.S. VIRGIN ISLANDS DURING THE NEXT 7
DAYS.

AT MID LEVELS...HIGH PRESSURE WILL WEAKEN OVER THE LOCAL AREA
WHILE GROWING IN THE CENTRAL ATLANTIC. A LOW THAT CUT OFF TODAY
OVER THE WESTERN TROPICAL ATLANTIC WILL MOVE EASTWARD AFTER
WEDNESDAY. HIGH PRESSURE WILL DOMINATE THE CARIBBEAN DURING THE
WEEK TO COME AND EARLY INTO THE FOLLOWING WEEK. MID LEVELS REMAIN
MOSTLY DRY.

AT LOWER LEVELS...HIGH PRESSURE WILL CONTINUE TO DOMINATE THE
CENTRAL ATLANTIC AND THE WATERS EAST. WEAK TROUGHING JUST WEST AND
OVER THE AREA WILL MAINTAIN EAST SOUTHEAST FLOW THROUGH WEDNESDAY.
FLOW WILL BECOME MOSTLY EASTERLY AFTER THAT.

&&

.DISCUSSION...A FEW SHOWERS IN THE EAST SOUTHEAST FLOW RODE INTO
PUERTO RICO...BUT GENERALLY DISSIPATED AFTER MOVING A FEW MILES
INLAND WITH ONLY TRACE AMOUNTS. SHOWERS WERE NOT DETECTED IN THE WATERS
AROUND THE U.S. VIRGIN ISLANDS. TEMPERATURES ON THE NORTHEAST
COAST SOARED IN THE SOUTHEAST FLOW...ESPECIALLY IN SAN JUAN WHERE
A DAILY RECORD OF 89 DEGREES WAS BROKEN WITH 91 DEGREES AT THE
LUIS MUNOZ MARIN AIRPORT THIS AFTERNOON.

FROM SATELLITE IMAGERY...MOST NOTABLE AT THIS TIME IS A BAND OF
MOISTURE THAT MOVED THROUGH THE WINDWARD ISLANDS EARLY LAST
NIGHT...THE LEEWARD ISLANDS TODAY...AND IS NOW APPROACHING THE U.S.
VIRGIN ISLANDS. THIS BAND IS DISSIPATING JUST AS THE ECMWF AND GFS
HAD FORECAST AND IS NOT EXPECTED TO BRING MUCH IF ANY RAINFALL TO
THE LOCAL AREA. A DRIER PATTERN IS EXPECTED TO CONTINUE WITH MINOR
VARIATIONS AS FLOW CONTINUES FROM THE EAST SOUTHEAST AT 850 MB. AT
THIS TIME LITTLE VARIATION IN THIS PATTERN IS BEING NOTED AND THE
MIMIC PRODUCT AND THE GFS FORECAST OF PRECIPITABLE WATER ARE
SHOWING MOST OF THE BEST MOISTURE WELL SOUTH OF THE AREA. HENCE
POPS WILL REMAIN LOW AND TEMPERATURES ABOVE NORMAL...ESPECIALLY ON
THE NORTHEAST COAST FOR THE NEXT SEVERAL DAYS. A FEW SHOWERS WILL
BE POSSIBLE IN THE WESTERN INTERIOR LATER IN THE WEEK...BUT ONLY
LIGHT AMOUNTS ARE EXPECTED.

&&

.AVIATION...VFR CONDS ARE EXPECTED TO CONTINUE WITH ONLY A FEW
CLOUDS TOPPING HIGHER PEAKS FROM TIME TO TIME NIGHTS AND MORNING
HOURS. WINDS IN THE LOWER LAYERS WILL BE EAST TO SOUTHEAST 5 TO 15
KNOTS...WITH SOME SEA BREEZE VARIATIONS.


&&

.MARINE...MODERATE TO FRESH WINDS ACROSS THE LOCAL WATERS WILL
KEEP SEAS UP TO 6 FEET WHERE NOT PROTECTED. SEAS WILL BE A LITTLE
LOWER SUNDAY AND MONDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 89 74 87 / 10 10 20 20
STT 74 87 74 85 / 30 20 30 20