Caribbean - Central America Weather

[Macrocane]

We've had much drier than normal conditions in most of Central America this week as we are under the supressed phase of the MJO. Things are slowly going to change and a low pressure will develop in Panama in the next few days increasing the moisture in the region as it moves slowly northward.

ROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
225 PM EDT TUE MAY 14 2013

DISCUSSION FROM MAY 14/00UTC: AMPLIFYING MID/UPPER LEVEL TROUGH
NOW DOMINATES FLOW OVER WESTERN ATLANTIC. THROUGH 24-30 HRS BASE
OF THE UPPER TROUGH IS TO ENTER THE BAHAMAS-NORTHERN CUBA...AND BY
42-48 HRS IT IS TO ENVELOP THE NORTHEAST CARIBBEAN ISLANDS. AT
72-84 HRS BASE OF THE TROUGH QUICKLY BEGINS TO PULL WHILE
MIGRATING INTO THE CENTRAL ATLANTIC. ON ITS WAKE...A LOW AMPLITUDE
TROUGH WILL REMAIN OVER THE NORTHEAST CARIBBEAN. MODELS CONTINUE
TO SHOW A SUBTROPICAL JET MAXIMA MOVING IN TANDEM WITH THIS
TROUGH...WITH JET MAXIMA TO QUICKLY ROUND THE BASE OF THE LONG
WAVE TROUGH AS IT PULLS ACROSS THE GREATER ANTILLES. ENVIRONMENTAL
CONDITIONS ARE TO THEN TO BECOME MORE FAVORABLE FOR DEEP
CONVECTION AS THE RIGHT ENTRANCE REGION SETTLES OVER THE FORECAST
AREA...WITH GFS SHOWING AN UPPER DIVERGENT PATTERN ESTABLISHING
ACROSS HISPANIOLA-PUERTO RICO-NORTHEAST CARIBBEAN ISLES. AT 500
HPA BEST INFLOW OF SHORT WAVE ENERGY/CYCLONIC VORTICITY IS
EXPECTED NORTH OF THE ISLANDS INTO THE WESTERN ATLANTIC. AT LOW
LEVELS THE ASSOCIATED SURFACE FRONT ENTERED THE NORTHWEST
BAHAMAS-SOUTH FLORIDA. THROUGH 24 HRS THE FRONT CONTINUES TO THE
CENTRAL BAHAMAS-CENTRAL/NORTHWEST CUBA. AT 36-42 HRS IT WILL
MEANDER TO THE SOUTHEAST BAHAMAS...WHILE TRAILING END REMAINS OVER
CENTRAL/WESTERN CUBA. THIS IS TO THEN REMAIN NEARLY STATIONARY
THROUGH 54-60 HRS. BY 72-84 HRS...AS IT LOSES UPPER LEVEL
SUPPORT...TRAILING END OF THE FRONT IS TO RETROGRESS ACROSS THE
BAHAMAS WHILE GRADUALLY WEAKENING. AS THE FRONT PUSHES ACROSS THE
BAHAMAS-CUBA IT IS TO TRIGGER ISOLATED TO SCATTERED CONVECTION
WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM/DAY.

A SOMEWHAT MORE ACTIVE PATTERN IS EXPECTED ACROSS HISPANIOLA AND
PUERTO RICO...WHERE AN INDUCED/PREFRONTAL LOW LEVEL TROUGH IS TO
ENHANCE MOISTURE CONVERGENCE. THE INVERTED TROUGH FORMS OVER
HISPANIOLA EARLY IN THE CYCLE...THEN MOVES TO PUERTO RICO THROUGH
36-48 HRS. ALTHOUGH IN AGREEMENT ON ITS EVOLUTION...THE MODEL
GUIDANCE DIVERGE ON IMPACT THIS IS GOING TO HAVE OVER THE FORECAST
AREA. THE EUROPEAN MODEL GENERALLY FAVORS A DRYER SOLUTION THAN
THE GFS-UKMET MODELS. TAKING INTO ACCOUNT UNFAVORABLE MJO
CONDITIONS ACROSS THE BASIN...WE NOW EXPECT MODERATE WITH LOCALLY
HEAVY RAINS TO DEVELOP IN ASSOCIATION WITH THIS FEATURE. ACROSS
HISPANIOLA IT WILL RESULT IN RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-35MM EARLY IN THE CYCLE...WITH MOST ACTIVE DURING THE
NEXT COUPLE OF DAYS. THIS QUICKLY BUILDS EAST ACROSS PUERTO RICO
THROUGH DAY 02. OVER THE NORTHERN LEEWARD ISLANDS...MEANWHILE...IT
WILL RESULT IN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM.

WEST OVER THE DOMAIN...A MID/UPPER LEVEL RIDGE CONTINUES TO
DOMINATE FLOW ACROSS CENTRAL AMERICA/WESTERN CARIBBEAN-SOUTHERN
MEXICO AND THE GULF. A 500 HPA HIGH OVER THE YUCATAN/CAMPECHE
SOUND IS TO ANCHOR THIS RIDGE. ALTHOUGH SOME EROSION OF THIS RIDGE
IS POSSIBLE ACROSS THE WESTERN CARIBBEAN/PORTIONS OF CENTRAL
AMERICA...FOR THE MOST PART IT WILL TEND TO HOLD AS IT LIES ACROSS
THE GULF-SOUTHERN STATES OF MEXICO. THIS WILL SUSTAIN A MID LEVEL
CAP INVERSION THAT IS TO CONTINUE INHIBITING ORGANIZED DEEP
CONVECTION. HOWEVER...WIDELY SCATTERED LATE AFTERNOON CONVECTION
IS STILL POSSIBLE ALONG THE CONTINENTAL DIVIDE TO SUSTAIN LIGHT
RAINFALL AMOUNTS.

A SHORT WAVE TROUGH MEANDERS ALONG THE NORTHERN FRINGES OF THIS
RIDGE. AS THE RIDGE HOLDS TO THE SOUTH...THE TROUGH IS FORECAST TO
LIFT TO THE EAST-NORTHEAST ACROSS THE NORTHERN STATES OF MEXICO TO
THE SOUTHERN USA. BEST INFLOW OF SHORT WAVE ENERGY IS EXPECTED
OVER THE NEXT 24-36 HRS...TO FOCUS ACROSS NORTHERN PORTIONS OF THE
SIERRA MADRE AND THE NORTHEAST STATES OF MEXICO. THIS IS TO
ENHANCE DIURNAL CONVECTION...TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM OVER THE NEXT COUPLE OF DAYS.

AT LOW LEVELS...A HIGH OVER THE SOUTHEAST USA ANCHORS A BROAD
RIDGE OVER THE SOUTHEAST USA/GULF OF MEXICO. THIS RIDGE IS TO HOLD
THROUGH 36-48 HRS...THEN WEAKEN LATER IN THE CYCLE WHILE
RELOCATING TO THE EAST-NORTHEAST. EARLY IN THE CYCLE THE RIDGE
WILL SUSTAIN A MOIST NORTHEASTERLY FLOW INTO THE SOUTHERN STATES
OF MEXICO...WITH FLOW CONVERGING ACROSS NORTHERN OAXACA-SOUTHERN
VERACRUZ TO CHIAPAS. THROUGH 36 HRS THIS FLOW IS EXPECTED TO
WEAKEN AS THE SURFACE HIGH MIGRATES. MEANWHILE...THIS IS TO FAVOR
SCATTERED CONVECTION WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15MM/DAY.

ANOTHER MID/UPPER LEVEL SHORT WAVE TROUGH LIES FARTHER TO THE
EAST...WITH AXIS SOUTH JUST EAST OF THE ISLAND CHAIN TO THE
NORTHERN GUIANAS. AS DEEP POLAR TROUGH ESTABLISHES TO THE WEST AND
NORTH...THE SHORT WAVE TROUGH IS EXPECTED TO QUICKLY WEAKEN WHILE
SHEARING ENERGY THROUGH 36-48 HRS. MEANWHILE...IT IS TO ENHANCE
CONVECTIVE DEVELOPMENT ACROSS THE GUIANAS. THIS IS TO FAVOR
SCATTERED CONVECTION OVER NORTHEAST VENEZUELA TO SURINAME AND
GUYANA...WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM
THROUGH 24-36 HRS. HIGHER AMOUNTS ARE EXPECTED OVER FRENCH GUIANA
TO AMAPA IN NORTHERN BRASIL...WHERE UNDER INFLUENCE OF A SOUTHERN
HEMISPHERE TROUGH/ITCZ CONVERGENCE EXPECTING RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM THROUGH 48-72 HRS.

OVER THE EASTERN PACIFIC...THE PANAMANIAN LOW DOMINATES THE LOW
LEVEL CIRCULATION...AS IT MEANDERS OFF THE COAST OF COLOMBIA WHILE
ANCHORING THE ITCZ ACROSS THE EJE CAFETERO. THROUGH 36 HRS THE LOW
BECOMES BETTER ORGANIZED...AND THIS IS TO ENHANCE LOW LEVEL
MOISTURE CONVERGENCE ALONG THE COAST INTO ANDEAN REGION IN
COLOMBIA. AFTER 54/60 HRS...THE LOW IS EXPECTED TO START A SLOW
WESTWARD MIGRATION ALONG THE ITCZ...TO THEN WEAKEN WHILE PULLING
FARTHER OFFSHORE. MEANWHILE...MESO SCALE CONVECTIVE SYSTEM (MCS)
DEVELOPMENT IS EXPECTED OFF THE COAST DURING THE NEXT COUPLE OF
DAY...WITH ACTIVITY ALONG THE FRINGES BUILDING EASTWARD ALONG THE
COAST. IN THIS AREA WE EXPECT RAINFALL AMOUNTS OF 15-20MM/DAY AND
MAXIMA OF 35-70MM/DAY...AND BY 48 HRS IT WILL PEAK AT 15-30MM/DAY
AND MAXIMA OF 40-80MM/DAY. THIS IS TO THEN DECREASE LATER IN THE
CYCLE TO 15-20MM/DAY AND MAXIMA OF 25-50MM. THE LOW...AS IT
INTENSIFIES...IS TO ALSO FAVOR A SLIGHT INCREASE IN CONVECTIVE
DEVELOPMENT ACROSS PANAMA. OVER WESTERN PORTIONS OF THE ISTHMUS
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM
LATER IN THE CYCLE...WHILE OVER EASTERN PANAMA EXPECT RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM OVER THE NEXT COUPLE OF
DAYS. OTHER CONVECTION IS EXPECTED ACROSS EASTERN COLOMBIA TO
NORTHEAST VENEZUELA...WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15-20MM/DAY.

BLENMAN...BMS (BARBADOS)
MCKENZIE...BDM (BAHAMAS)
DAVISON/GALVEZ...WPC (USA)

[cycloneye]

Good morning. Afternoon showers and a few thunderstorms will fall in PR this afternoon but after Saturday,moisture increases in the Eastern Caribbean so stay tuned for that.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
424 AM AST WED MAY 15 2013

.SYNOPSIS...UPPER LEVEL TROF OVR THE WRN ATLC EAST OF 70W WILL
SWING BY NORTH OF THE AREA TODAY. WEAK MID LEVEL HIGH PRES WILL
BUILD OVR THE AREA LATE THU AND FRI. ANOTHER TROF WILL IMPACT THE
AREA EARLY NEXT WEEK.

&&

.DISCUSSION...MODEL TRENDS SINCE YESTERDAY SHOW A WEAKER TROF
PASSING NORTH OF THE AREA TODAY WITH BEST FORCING STAYING NORTH OF
19.5N. AS A RESULT...GUIDANCE IS NOW SHOWING LESS PRECIP FOR TODAY
THAN YDAY. HOWEVER...ANY SHOWERS THAT DO FORM WILL BE VERY SLOW
MOVERS DUE TO VERY WEAK OR ILL-DEFINED STEERING CURRENTS WITH THE
POTENTIAL TO PRODUCE LOCALIZED HEAVY RAINFALL AND ISOLD FLASH
FLOODING. MID LEVEL HIGH PRES BUILDS OVER THE AREA BY FRI WITH
MODELS SHOWING SIG DRYING FRI THROUGH SAT.

LATE SAT NIGHT THRU MID NEXT WEEK...MODELS SHOW MID LEVEL HIGH
PRES DISSIPATING AS ANOTHER TROF MOVES INTO THE BAHAMAS. THIS WILL
PROMOTE MOISTURE TRANSPORT AND ENHANCE CONVECTIVE INSTABILITY WITH
AN INCREASE IN AREAL COVERAGE OF SHOWERS EXPECTED SUN AND INTO
EARLY NEXT WEEK. BY TUE AND WED...MOISTURE BECOMES VERY DEEP WITH
PW VALUES WELL OVER 2.0 INCHES AS TRADE WIND CONVERGENCE INCREASES
OVR THE ISLAND. TIMING DIFFERENCES BECOME MORE EVIDENT NEXT WEEK
WITH GFS BEING FASTER THAN ECMWF IN BRINGING A DEEP SURGE IN
MOISTURE BUT OVERALL TREND SHOULD BE FOR VERY WET WEATHER MID TO
LATE NEXT WEEK AS EQUATORIAL TROUGH LIFTS NORTHWARD.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL ACROSS ALL TAF SITES UNTIL
15/12Z. HOWEVER...ISOLATED PASSING SHRA WILL MOVE WEST ACROSS THE
COASTAL WATERS BETWEEN PR AND THE LESSER ANTILLES. THIS WILL RESULT
IN BRIEF MOUNTAIN OBSCURATIONS OVER EASTERN PR WITH PERIODS OF MVFR
CONDITIONS DUE TO THE PASSING LOW CLDS AND SHRA. AFTERNOON SHRA/TSRA
ARE EXPECTED OVER THE INTERIOR AND NORTH SECTIONS OF PR...AFFECTING
MAINLY TJMZ...TJBQ AND TJSJ FROM 15/18-23Z. WINDS WILL BE FROM THE
EAST TO SOUTHEAST AT 5-15 KTS UP TO 2 KFT THROUGH THE FCST PERIOD.

&&

.MARINE...SEAS 2-4 FT INCREASING 5-6 FT OVR THE WEEKEN ON
NORTHEAST SWELLS. TSTMS WILL BE THE MAIN WX HAZARD.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 87 77 86 77 / 20 20 40 10
STT 86 79 87 79 / 20 20 20 20

[cycloneye]

Code: Select all

JAMAICA WEATHER

 LOCAL FORECAST

May 15 2013
 

Significant Feature: A surface trough across the central Caribbean.

Morning:  Mostly sunny.

Afternoon:  Partly cloudy with isolated showers mainly over interior areas.

Tonight: Fair.

Winds:  Will reach in excess of 15 knots (18 mph)

Temperatures: High: 32C (90F)     Low: 25C (77F)
 


[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
305 PM AST WED MAY 15 2013

.SYNOPSIS...UPPER LEVEL TROUGH PASSING JUST NORTH OF PUERTO
RICO..WILL KEEP UNSTABLE ATMOSPHERIC CONDITIONS THROUGH AT LEAST
FRIDAY. SURFACE HIGH PRESSURE WILL BUILD ACROSS THE LOCAL AREA
DURING THE WEEKEND. ANOTHER UPPER LEVEL TROUGH WILL MOVE ACROSS THE
AREA EARLY NEXT WEEK.

&&

.DISCUSSION...VERY ACTIVE DAY ACROSS PUERTO RICO...WITH VERY HEAVY
RAIN REPORTED ACROSS THE EAST AND SOUTHEAST SECTIONS OF PUERTO
RICO...WHERE U.S.G.S RIVER SENSOR INDICATED OVER 3 INCHES IN ONE
HOUR FELL OVER LAS PIEDRAS. ALSO...ANOTHER AREA WHICH RECEIVED
BETWEEN 1 TO 3 INCHES OF RAINFALL WAS THE WESTERN INTERIOR AND
WEST SECTION OF PUERTO RICO. AN UPPER LEVEL THROUGH COMBINED WITH
DAYTIME HEATING AND GOOD MOISTURE AT THE SURFACE...TO PRODUCE
SCATTERED TO NUMEROUS SHOWERS WITH THUNDERSTORMS.

THE AFOREMENTIONED UPPER LEVEL TROUGH WILL MOVE AWAY FROM THE AREA
THURSDAY. HOWEVER...LINGERING MOISTURE WILL COMBINE ONCE AGAIN WITH
LOCAL EFFECT TO PRODUCE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS
MAINLY ALONG AND NORTH OF THE CORDILLERA CENTRAL UN THE AFTERNOON
HOURS. A SURFACE HIGH PRESSURE IS THEN EXPECTED TO BUILD ACROSS
THE AREA DURING THE WEEKEND..WHICH WILL LIMIT SOMEWHAT THE CHANCES
FOR SHOWER ACTIVITY. BUT IN GENERAL...CONDITIONS WILL REMAIN
FAVORABLE FOR SOME KIND OF SHOWER DEVELOPMENT EACH AFTERNOON.

FOR NEXT WEEK...COMPUTER MODELS INDICATED ANOTHER UPPER LEVEL
THROUGH WILL APPROACH THE LOCAL REGION. WET CONDITIONS WILL
RETURN TO OUR LOCAL AREA BY MID WEEK...AS THIS TROUGH ESTABLISHES
CLOSE TO OUR AREA.

&&

.AVIATION...MVFR/IFR CONDITIONS ARE POSSIBLE UNTIL AROUND 15/23Z
ACROSS TJMZ...TJBQ...AND TJSJ SUE TO SHOWERS AND THUNDERSTORMS OVER
PR. WINDS WILL CONTINUE FROM THE EAST SOUTHEAST WITH SEA BREEZE
VARIATIONS AT AROUND 10 KTS AND GUSTY NEAR SHRA/TSRA. MOUNTAIN
OBSCURATIONS AND VARIABLY GUSTY WINDS CAN BE EXPECTED. WEATHER
CONDITIONS EXPECTED TO IMPROVE AFTER 16/00Z BUT CEILINGS WILL REMAIN
GENERALLY AROUND FL040-060 UNTIL 16/02Z. SCATTERED CLOUDS AND WINDS
FROM THE EAST AT 10 KTS OR LESS EXPECTED THEREAFTER.

&&

.MARINE...SEAS OF 5 FEET OR LESS AND WINDS OF 15 KNOTS OR LES ARE
EXPECTED TO PREVAIL ACROSS THE COASTAL WATERS.

&&

.HYDROLOGY...SEVERAL RIVERS REMAINS AT HIGH LEVEL...AN WILL
CONTINUE TO RISE MAINLY OVER THE EASTERN HALF OF PUERTO RICO...AND
OVER THE WESTERN INTERIOR AND WEST SECTIONS OF PUERTO RICO. PEOPLE
LIVING AT OR CLOSE TO RIO ESPIRITU SANTO...IN RIO GRANDE... RIO
BLANCO IN NAGUABO...RIO ANASCO...RIO CULEBRINAS AND RIO GRANDE DE
ARECIBO BE ALERT IN CASE OF A FLASH FLOOD WARNING IS ISSUED.
ELSEWHERE...RESIDENTS AND MOTORISTS SHOULD BE ALERT TO PONDING OF
WATER ON ROADWAYS AND ALLOW TIME FOR STREAMS...CREEKS AND RIVERS
TO RETURN TO NORMAL LEVELS...AS RUNOFF WILL CONTINUE TO AFFECT
THESE AREAS DURING THE NEXT HOUR OR SO.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 86 77 86 / 20 40 10 20
STT 79 87 79 85 / 20 20 20 20

[cycloneye]

Hi BZSTORM and rest of Caribbean and Central American friends. Things look very rainy for next week in most of the Caribbean according to the models. Let's pay attention to this in the coming days and I will keep all informed.

NAVGEM



GFS

[Macrocane]

Rainy season is about to start in Central America. Today tropical depression 1E and a low pressure south of Panama have developed and the first tropcial wave of the season is halfway between Africa and South America.

[Macrocane]

Still dry in northern Central America on the next few days but very wet in the southern portion of the region:

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
229 PM EDT WED MAY 15 2013

DISCUSSION FROM MAY 15/00UTC: AN AMPLIFYING MID/UPPER LEVEL TROUGH
IS INITIALIZED OVER THE WESTERN ATLANTIC TO THE BAHAMAS-CUBA. AS A
JET MAXIMA ROUNDS THE BASE OF THIS TROUGH...DIVERGENCE ON ITS
RIGHT ENTRANCE REGION IS ENHANCING CONVECTIVE DEVELOPMENT ACROSS
PORTIONS OF HISPANIOLA. THE UPPER TROUGH PROPAGATES ACROSS THE
NORTHEAST CARIBBEAN ISLANDS DURING THE DAY TODAY...WITH UPPER
DIVERGENCE SPREADING ACROSS PUERTO RICO-VIRGIN ISLES TO THE
LEEWARD ISLANDS. UPPER DIVERGENCE ACROSS PUERTO RICO-VI WEAKENS
THROUGH 42-48 HRS...WHILE OVER THE FRENCH-NORTHERN LEEWARD ISLANDS
IT IS EXPECTED TO PERSIST THROUGH 60-66 HRS

AT LOW LEVELS...A POLAR FRONT TRAILS TO THE WEST-SOUTHWEST ALONG
30N 60W...SOUTHEAST BAHAMAS TO CUBA. AHEAD OF THIS BOUNDARY...AN
INDUCED/PREFRONTAL TROUGH EXTENDS NORTH ACROSS PUERTO RICO TO THE
WESTERN ATLANTIC. THE TROUGH IS GOING TO BE SHORT LIVED...
WEAKENING EARLY IN THE FORECAST CYCLE. THIS FAVORS A MOIST
EAST-SOUTHEAST FLOW ACROSS THE LEEWARD ISLES/CARIBBEAN WATERS OF
PUERTO RICO...WITH MOISTURE CLUSTERING OFF THE CARIBBEAN COAST OF
HISPANIOLA. TRAILING END OF THE SURFACE FRONT REMAINS NEARLY
STATIONARY OVER THE SOUTHEAST BAHAMAS-CENTRAL/WESTERN CUBA THROUGH
36-48 HRS. BY 48-60 HRS IT WILL RETROGRESS INTO THE NORTHWEST
BAHAMAS WHERE IT IS EXPECTED TO QUICKLY DISSIPATE. AS THE FRONT
MEANDERS ACROSS THE BAHAMAS-CUBA IT IS TO TRIGGER ISOLATED TO
SCATTERED CONVECTION WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15MM/DAY.

BUT AS THE SURFACE FRONT STALLS FAR TO THE NORTH...LIGHT TO
MODERATE EASTERLY TRADES ARE TO PERSIST ACROSS THE LEEWARD-VIRGIN
ISLES TO PUERTO RICO AND PORTIONS OF HISPANIOLA. MOIST PLUME IS TO
CLUSTER OVER THE NORTHEAST CARIBBEAN DURING THE NEXT COUPLE OF
DAYS WHILE EXTENDING BETWEEN THE FRENCH ISLES TO JUST SOUTH OF
HISPANIOLA. AT 60-72 HRS MOISTURE WILL SPREAD WEST INTO JAMAICA
WHILE IT STARTS TO EBB OVER THE NORTHEAST CARIBBEAN/LEEWARD
ISLANDS. ACROSS HISPANIOLA THIS IS TO FAVOR RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM THROUGH 72 HRS. OVER PUERTO RICO
EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF
20-35MM...WITH MOST ACTIVE ALONG THE CORDILLERA AND WESTERN
INTERIOR PORTIONS OF THE ISLAND. THROUGH 72-96 HRS THIS WILL
DECREASE TO 05-10MM/DAY AND MAXIMA OF 15MM. OVER THE FRENCH
ISLANDS...UNDER FAVORABLE JET DYNAMICS...TRADE WINDS CONVERGENCE
IS TO FAVOR RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF
20-35MM/DAY...WITH MAXIMA INCREASING TO 20-45MM BY 48-60 HRS.
THROUGH 72-84 HRS THIS WILL DECREASE TO 05-10MM/DAY AND MAXIMA OF
15MM/DAY. AS MOISTURE SPREADS ACROSS THE NORTHERN CARIBBEAN OVER
JAMAICA EXPECTING ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF
15MM...TO PEAK AT 20-35MM AT 48-72 HRS.

A 500 HPA HIGH OVER THE SOUTHERN GULF/CAMPECHE SOUND ANCHORS A MID
LEVEL RIDGE ACROSS CENTRAL-SOUTHERN MEXICO-CENTRAL AMERICA AND THE
WESTERN CARIBBEAN. AS PERTURBATIONS ON THE SOUTHERN STREAM LIFT
OVER THIS AXIS...RIDGE OVER THE GULF TENDS TO ERODE. OVER
MEXICO-CENTRAL AMERICA...HOWEVER... IT WILL TEND TO PERSIST THROUGH
AT LEAST 84-96 HRS. AS IT HOLDS...THE RIDGE IS TO CONTINUE
FAVORING A SUBSIDENCE CAP WHILE INHIBITING ORGANIZED DEEP
CONVECTION. HOWEVER...WIDELY SCATTERED LATE AFTERNOON CONVECTION
IS STILL POSSIBLE ALONG THE CONTINENTAL DIVIDE OVER SOUTHERN
GUATEMALA-HONDURAS/NORTHERN EL SALVADOR WHERE IT IS TO RESULT IN
LIGHT RAINFALL AMOUNTS.

OVER THE EASTERN PACIFIC...THE PANAMANIAN LOW CONTINUES TO
DOMINATE THE LOW LEVEL CIRCULATION OFF THE COAST OF COLOMBIA INTO
THE ANDEAN REGION. AS IT HOLDS...THE LOW ANCHORS THE ITCZ AS IT
ENTERS COLOMBIA OVER THE EJE CAFETERO. THE LOW REACHES MAXIMUM
INTENSITY EARLY IN THE CYCLE...AND THROUGH 42-48 HRS IT WILL START
TO MIGRATE WEST ALONG THE ITCZ INTO THE PACIFIC. BY 60-72 HRS THE
SURFACE LOW IS TO DISSIPATE/WEAKEN. AS IT PULLS AWAY THE ITCZ IS
TO MEANDER NORTH INTO THE AZUERO PENINSULA IN SOUTHERN PANAMA. THE
SURFACE LOW...AS IT MEANDERS OFF THE COAST OF COLOMBIA EARLY THIS
CYCLE...IS TO ENHANCE LOW LEVEL MOISTURE CONVERGENCE ALONG THE
COAST AND ANDEAN REGION INTO THE DARIEN IN EASTERN PANAMA. DURING
SHORT RANGE PERIOD THIS IS TO CONTINUE FAVORING GENERATION OF MESO
SCALE CONVECTIVE SYSTEMS. IN THIS AREA WE EXPECT RAINFALL AMOUNTS
OF 15-30MM/DAY AND MAXIMA OF 40-80MM/DAY. THIS IS TO THEN DECREASE
THROUGH 48-72 HRS TO 10-15MM/DAY AND MAXIMA OF 20-40MM. AS THE LOW
MODULATES THE ITCZ...ACROSS PANAMA EXPECTING LIGHT TO MODERATE
CONVECTION TO RESULT IN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA
OF 15-25MM. THIS SPREADS TO COSTA RICA BY 60-84 HRS...WITH
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM/DAY. OTHER
CONVECTION IS EXPECTED ACROSS EASTERN COLOMBIA TO NORTHEAST
VENEZUELA...WITH RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM/DAY.

NORTHERN SOUTH AMERICA IS UNDER INFLUENCE OF THE SUBEQUATORIAL
RIDGE...WITH AXIS TO MEANDER ACROSS NORTHERN BRASIL INTO THE
GUIANAS-VENEZUELA. RIDGE PATTERN HOLDS NEARLY UNCHANGED OVER THE
NEXT FEW DAYS. A CELL OF THE SUBTROPICAL RIDGE TO THE SOUTH...
HOWEVER...IS FORECAST TO STRENGTHEN THROUGH 60-72 HRS. AS THE
RIDGE BECOMES BETTER ORGANIZED IT WILL SUSTAIN A CROSS EQUATORIAL
TROUGH ACROSS NORTHEAST BRASIL INTO THE TROPICAL ATLANTIC. THE
UPPER TROUGH WILL INTERACT WITH THE ITCZ IN SUPPORT OF ORGANIZED
DEEP CONVECTION ACROSS NORTHERN FRENCH GUIANA TO SURINAME. IN THIS
AREA INITIALLY EXPECT RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA
OF 20-45MM. THROUGH 48-72 HRS THIS WILL DECREASE TO 05-10MM/DAY
AND MAXIMA OF 15-30MM. OVER NORTHERN GUYANA CONVECTION IS TO
INCREASE THROUGH 60-84 HRS. INITIALLY EXPECTING RAINFALL
ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15MM...TO INCREASE TO
10-15MM/DAY AND MAXIMA OF 20-35MM.

[cycloneye]

Good morning. Afternoon showers will again fall in PR but the bigger story will be the next week's big rain event that is forecast for most of the Caribbean.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
422 AM AST THU MAY 16 2013

.SYNOPSIS...UPPER LEVEL TROUGH WILL MOVE ACROSS THE AREA LATER
TODAY. WEAK MID-LEVEL HIGH PRES WILL BUILD OVR THE AREA TONIGHT
AND FRI. ANOTHER TROUGH WILL AFFECT MOST OF THE CARIB NEXT WEEK.

&&

.DISCUSSION...STILL SCT-NMRS SHRA/TSRA ACTIVITY TODAY AS UPPER
LEVE TROF AXIS WILL BE SLOW TO MOVE ACROSS THE AREA BUT ACTIVITY
ISN`T LIKELY TO BE AS INTENSE AS IT WAS YDAY. SHARPER DRYING IS
EXPECTED TONIGHT THRU SAT UNDER UPPER LEVEL CONVERGENT FLOW ON
BACKSIDE OF DEPARTING TROF AND WEAK MID LEVEL HIGH PRES.

MOISTURE GRADUALLY INCREASES LATE SAT THROUGH EARLY NEXT WEEK AS
ANOTHER TROF MOVES INTO THE BAHAMAS AND PROMOTES MOISTURE
TRANSPORT AND ENHANCES MID LEVEL INSTABILITY. STRENGTHENING HIGH
PRES ACROSS THE ATLC MID NEXT WEEK WILL TIGHTEN THE PRES GRADIENT
WITH STRENGTHENING TRADE WINDS ALLOWING FOR DEEPER MOISTURE TO
CONVERGE OVR THE AREA SETTING UP A POTENTIALLY SIGNIFICANT
RAINFALL EVENT MIDDLE OF NEXT WEEK. ANOMALOUS DEEP TROUGH AT H5
FCST TO EXTEND FROM THE BAHAMAS INTO THE WRN CARIB WILL HELP
INDUCE A SWRLY MID LEVEL FLOW WITH AN EPAC MOISTURE CONNECTION
FCST TO CONVERGE OVR HISPANIOLA...CARIBBEAN COASTAL WATERS AND
POSSIBLY PR. OVERALL TREND IS FOR INCREASINGLY CLOUDY AND WET
CONDITIONS MIDDLE TO LATTER PART OF NEXT WEEK.

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES UNTIL ARND
16/16Z. MVFR/IFR CONDS WILL BEGIN DEVELOPING AFT 16/16Z ALONG THE
CORDILLERA CENTRAL AND ARND TJMZ IN AREAS OF +SHRA/TSRA. MOUNTAINS
WILL BE OBSCURED. CONDS WILL IMPROVE AFTER 16/21Z AS DRIER AIR MOVES
IN. FOR THE LEEWARD ISLANDS...MVFR CONDS ARE PSBL AFTER 16/21Z AT
TKPK OTHERWISE EXPECT VFR. WINDS WILL BE MAINLY ESE 10 TO 15 KTS
FROM SFC UP TO 2 KFT.

&&

.MARINE...SEAS 2-4 FT INCREASING TO 5 FT OVR THE WEEKEND IN MIXED
NORTHEAST SWELLS AND EASTERLY WIND WAVES. TSTMS WILL REMAIN THE
PRIMARY HAZARD MAINLY OVER CARIB WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 77 87 77 / 40 20 20 0
STT 87 79 87 79 / 30 20 20 10

[cycloneye]

Code: Select all

JAMAICA WEATHER

 LOCAL FORECAST

May 16 2013
 

Significant Feature: A surface trough across the central Caribbean.

Morning:  Mostly sunny.

Afternoon:  Partly cloudy with scattered showers mainly over central and western parishes.

Tonight: Fair.

Winds:  Will reach in excess of 10 knots (12 mph)

Temperatures: High: 32C (90F)     Low: 25C (77F)
 


[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
250 PM AST THU MAY 16 2013

.SYNOPSIS...UPPER TROUGH WILL CONTINUE TO MOVE THROUGH THE AREA
TODAY INTO TOMORROW AS IT WEAKENS. SURFACE HIGH PRESSURE WILL
REMAIN TO THE NORTH OF THE LOCAL ISLANDS THROUGH SATURDAY.
ENOUGH MOISTURE IS EXPECTED FOR THE NEXT SEVERAL DAYS TO HELP WITH
THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS EACH AFTERNOON FOR
THE NEXT SEVERAL DAYS.

&&

.DISCUSSION...SHOWERS AND THUNDERSTORMS DEVELOPED ACROSS PUERTO
RICO THIS AFTERNOON AND THIS ACTIVITY IS EXPECTED TO DIMINISH IN
THE EVENING HOURS. THEREAFTER...ISOLATED PASSING SHOWERS ARE
EXPECTED ACROSS THE LOCAL AREA AS MOISTURE DECREASES SLOWLY
OVERNIGHT. HOWEVER...AVAILABLE MOISTURE INCREASES ONCE AGAIN ON
FRIDAY AFTERNOON TO HELP WITH THE DEVELOPMENT OF SHOWERS AND
THUNDERSTORMS WHEN COMBINED WITH LOCAL EFFECTS AND DIURNAL
HEATING WITH THE MORE NUMEROUS SHOWERS EXPECTED TO OCCUR OVER THE
WESTERN INTERIOR AND WESTERN SECTIONS OF PUERTO RICO. HOWEVER...THE COVERAGE
AREA IS EXPECTED TO BE LESS THAN IT HAS BEEN FOR THE LAST FEW DAYS
DUE TO LESS AVAILABLE MOISTURE...ESPECIALLY IN THE MID LEVELS. THE
SAME COULD BE SAID FOR SATURDAY.

SUNDAY ONTO NEXT WEEK...MOISTURE INCREASES ONCE AGAIN AND
ACCORDING TO THE GFS MODEL...PRECIPITABLE WATER VALUES INCREASE
CLOSE TO 2 INCHES BY EARLY NEXT WEEK...STAYING AROUND 2 INCHES FOR
A GOOD PART OF NEXT WEEK. GFS MODEL ALSO HAS THE LOCAL ISLANDS
UNDER SOME FAIRLY CONSISTENT RAIN WITH THIS MOISTURE UNDER A
SOUTHEAST FLOW.

&&

.AVIATION...VFR CONDITIONS EXPECTED TO PREVAIL AT ALL TAF SITES
FOR THE NEXT 24 HRS...WITH BRIEF MVFR CONDITIONS POSSIBLE IN
SHRA/TSRA AT TJMZ/TJPS AND TJBQ THROUGH ABOUT 16/22Z. SURFACE
WINDS FROM THE EAST AT 10 TO 15 KTS.


&&

.MARINE...SMALL CRAFT SHOULD EXERCISE CAUTION STARTING LATE
TONIGHT AND TOMORROW ACROSS THE ATLANTIC OFFSHORE WATERS AS SEAS
ARE EXPECTED TO REACH 6 FEET. SEAS EXPECTED TO REACH UP TO 5 FEET
ON SATURDAY AND THEN INCREASE UP TO 6 FEET ON SUNDAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 78 87 77 86 / 20 20 0 20
STT 78 88 78 88 / 20 20 10 20

[cycloneye]

Here is Rob of Crownweather discussing about the rainy scenario for most of Caribbean and maybe also Tropical Development.

http://www.crownweather.com/?p=7358

I continue to closely monitor the idea of a strong upward motion pulse of the Madden Julian Oscillation that is expected to track into the Caribbean between May 24th and May 29th. This pulse of upward moving air will lead to enhanced rainfall and lowering barometric pressures. This upward MJO pulse can also lead to tropical cyclone development and this is what may occur during the first week of June in the southwestern Caribbean.

Even if tropical cyclone development does not occur in early June, a heavy rainfall and flash flood/mudslide threat may materialize across Haiti, the Dominican Republic and Puerto Rico by about Memorial Day weekend. So, all of our Crown Weather friends in these areas should be aware of this possibility.

Other than that, the tropical Atlantic is quiet with no other areas of concern. I will continue to monitor the possibility of western Caribbean tropical development for the beginning of June closely and will continue to have frequent updates.

[Macrocane]

The temperatures in Central America on May 14, 2013

Minimum Temperatures

Belize city, Belize 23.0°C (73.4°F)
Guatemala city, Guatemala 15.7°C (60.3°F)
Quetzaltenango, Guatemala 9.7°C (49.5°F)
Zacapa, Guatemala 22.0°C (71.6°F)
San Salvador, El Salvador 20.0°C (68.0°F)
Las Pilas, El Salvador 11.2°C (52.5°F)
San Miguel, El Salvador 23.8°C (74.8°F)
Tegucigalpa, Honduras 19°C (66°F)
La Esperanza, Honduras 14°C (57°F)
Choluteca, Honduras 27°C (81°F)
Managua, Nicaragua 24°C (75°F)
Jinotega, Nicaragua 19°C (66°F)
San Jose, Costa Rica 18.2°C (64.8°F)
Irazu volcano, Costa Rica 4.1°C (39.4°F)
Liberia, Costa Rica 23.9°C (75.0°F)
Panama city, Panama 25.4°C (77.7°F)
Boquete, Panama 18.6°C (65.5°F)

Maximum Temperatures

Belize city, Belize 31.0°C (87.8°F)
Guatemala city, Guatemala 23.7°C (74.7°F)
Quetzaltenango, Guatemala 20.7°C (69.3°F)
Zacapa, Guatemala 33.0°C (91.4°F)
San Salvador, El Salvador 32.5°C (90.5°F)
Las Pilas, El Salvador 19.8°C (67.6°F)
San Miguel, El Salvador 40.0°C (104.0°F)
Tegucigalpa, Honduras 30°C (86°F)
La Esperanza, Honduras 23°C (73°F)
Choluteca, Honduras 36°C (97°F)
Managua, Nicaragua 36°C (97°F)
Jinotega, Nicaragua 28°C (82°F)
San Jose, Costa Rica 25.2°C (77.4°F)
Irazu volcano, Costa Rica 10.7°C (51.3°F) Codest since March 29, 2013
Liberia, Costa Rica 36.0°C (96.8°F)
Panama city, Panama 33.3°C (91.9°F)
Boquete, Panama 24.3°C (75.7°F)

[Macrocane]

Temperatures in Central America on May 15, 2013

Minimum Temperatures

Belize city, Belize 24.1°C (75.4°F)
Guatemala city, Guatemala 14.0°C (57.2°F) Coldest since March 31, 2013
Quetzaltenango, Guatemala 6.0°C (42.8°F)
Zacapa, Guatemala 21.0°C (69.8°F)
San Salvador, El Salvador 18.6°C (65.5°F)
Las Pilas, El Salvador 9.5°C (49.1°F)
San Miguel, El Salvador 24.4°C (75.9°F)
Tegucigalpa, Honduras 19°C (66°F)
La Esperanza, Honduras 13°C (55°F)
Choluteca, Honduras 27°C (81°F)
Managua, Nicaragua 25°C (77°F)
Jinotega, Nicaragua 18°C (64°F)
San Jose, Costa Rica 17.9°C (64.2°F)
Irazu volcano, Costa Rica 3.1°C (37.6°F) Coldest since April 6, 2013
Liberia, Costa Rica 24.0°C (75.2°F)
Panama city, Panama 25.6°C (78.1°F) Warmest since April 7, 2013
Boquete, Panama 17.3°C (63.1°F)

Maximum Temperatures

Belize city, Belize 31.4°C (88.5°F)
Guatemala city, Guatemala 25.8°C (78.4°F)
Quetzaltenango, Guatemala 20.7°C (69.3°F)
Zacapa, Guatemala 34.6°C (94.3°F)
San Salvador, El Salvador 32.8°C (91.0°F)
Las Pilas, El Salvador 20.9°C (69.6°F)
San Miguel, El Salvador 41.0°C (105.8°F) Hottest since March 7, 2013
Tegucigalpa, Honduras 30°C (86°F)
La Esperanza, Honduras 23°C (73°F)
Choluteca, Honduras 37°C (99°F)
Managua, Nicaragua 35°C (95°F)
Jinotega, Nicaragua 28°C (82°F)
San Jose, Costa Rica 26.8°C (80.2°F)
Irazu volcano, Costa Rica 11.3°C (52.3°F)
Liberia, Costa Rica 34.7°C (94.5°F)
Panama city, Panama 32.4°C (90.3°F)
Boquete, Panama 23.3°C (73.9°F)

[cycloneye]

Good morning. The weekend will be in part with good weather on Saturday and more rainy on Sunday. Next week looks very rainy in most of the Caribbean.

AREA FORECAST DISCUSSION...DELAYED
NATIONAL WEATHER SERVICE SAN JUAN PR
558 AM AST FRI MAY 17 2013

.SYNOPSIS...BASE OF MID TO UPPER LEVEL TROUGH NOW ACROSS THE
NORTHERN LEEWARDS...AND EXTENDS INTO THE SOUTHEASTERN CARIBBEAN...
WITH WEAK UPPER RIDGE EXTENDING ACROSS THE MONA PASSAGE WITH ANOTHER
THIS WILL NOW PLACE THE REGION ON THE CONVERGENT SIDE OF THE UPPER
TROUGH AND SHOULD THEREFORE LIMITED WIDESPREAD CONVECTIVE DEVELOPMENT
TODAY. AT LOW LEVELS...SURFACE HIGH PRESSURE CENTERED ACROSS THE NORTH
CENTRAL ATLANTIC WILL SPREAD AND REESTABLISH ITSELF NORTH OF THE
REGION BY SATURDAY THEN GRADUALLY TIGHTEN THE LOCAL PRESSURE GRADIENT
ACROSS THE NORTH EAST CARIBBEAN. THIS WILL ALLOW FOR AN INCREASE IN
THE EASTERLY TRADE WINDS OVER THE WEEKEND AND INTO EARLY NEXT WEEK.

&&

.DISCUSSION...UPPER TROUGH WILL CONTINUE SHIFT EASTWARDS ACROSS THE
NORTHEAST CARIBBEAN WHILE WEAKENING. LOOKING FOR INCREASING SUBSIDENCE
CAP LATER THIS EVENING AND THROUGH SATURDAY. HOWEVER...THE PERSISTENT
AND GRADUALLY INCREASING EASTERLY TRADES WILL BRING SHALLOW PATCHES
OF LOW TO MID LEVEL MOISTURE ACROSS THE AREA FROM TIME TO TIME.
THEREFORE...EXPECT SUFFICIENT LOW LEVEL MOISTURE CONVERGENCE AND
DIURNAL EFFECTS TO ALLOW FOR AFTERNOON CONVECTIVE DEVELOPMENT IN
SOME AREAS ESPECIALLY ACROSS PARTS OF THE INTERIOR AND WEST SECTIONS
OF PUERTO RICO.

INTO THE WEEKEND...LOOKING FOR A GRADUAL DRYING TREND ACROSS THE
REGION AT LEAST UNTIL SATURDAY. THIS WILL BE FOLLOWED BY INCREASING
MOISTURE AND PWAT VALUES SUNDAY INTO THE EARLY PART OF NEXT WEEK...AS
ANOTHER SHORT WAVE TROUGH WILL APPROACH THE REGION FROM THE WEST
WHILE AN EASTERLY PERTURBATION IS FORECAST TO BRING AN INCREASE IN
TRADE WIND MOISTURE TO THE ISLANDS AND SURROUNDING WATERS. FOR NOW
BASED ON LATEST MODEL GUIDANCE...EXPECT BETTER CHANCE FOR ENHANCEMENT
OF EARLY MORNING AND AFTERNOON CONVECTION DURING THAT PERIOD. UNTIL
THEN...STILL EXPECT AFTERNOON SHOWERS TO DEVELOP WITH MAINLY ISOLATED
THUNDERSTORMS EACH DAY...ESPECIALLY IN ISOLATED AREAS OVER THE INTERIOR
SECTIONS OF PUERTO RICO...THEN DECREASING BY EARLY EVENING HOURS.

&&

.AVIATION...MOSTLY VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES UNTIL
AROUND 17/16Z. MVFR OR EVEN IFR CONDITIONS ARE LIKELY BETWEEN
17/18Z-21Z ALONG THE CORDILLERA CENTRAL AND AROUND TJMZ IN AREAS OF
+SHRA/TSRA. MOUNTAINS WILL BE OBSCURED OVER WESTERN INTERIOR OF PR.
ELSEWHERE...VFR CONDITIONS ARE EXPECTED. TJSJ 17/00Z SOUNDING
INDICATED AN EASTERLY WIND FLOW UP TO 10 KNOTS ALL THE WAY FROM THE
SURFACE TO 20K FEET...BECOMING WESTERLY AND STRONGER ALOFT.

&&

.MARINE...SMALL CRAFT SHOULD EXERCISE CAUTION MAINLY ACROSS THE LOCAL
OFFSHORE WATERS...AS SEAS ARE EXPECTED TO REACH 6 FEET THROUGH THE
WEEKEND WITH INCREASING TRADE WINDS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 76 87 77 / 10 0 20 20
STT 86 76 88 78 / 10 10 20 30

[cycloneye]

Code: Select all

JAMAICA WEATHER

 LOCAL FORECAST

May 17 2013
 

Significant Feature: A surface trough across the central Caribbean.

Morning:  Mainly fair.

Afternoon:  Partly cloudy with scattered showers mainly over central and western parishes.

Tonight: Fair.

Winds:  Will reach in excess of 10 knots (12 mph)

Temperatures: High: 32C (90F)     Low: 25C (77F)
 


[cycloneye]

The Cayman islands radar is going to be operational very soon but already is working on a partial way. It will be very important as the Tropical Systems move thru that area. I added it to the first post of this thread.

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
256 PM AST FRI MAY 17 2013

.SYNOPSIS...A MID TO UPPER LEVEL TROUGH ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL CONTINUE TO MOVE EAST AND AWAY FROM
THE LOCAL ISLANDS. LOCAL PRESSURE GRADIENT WILL TIGHTEN AS SURFACE
HIGH BUILDS AND RELOCATES TO THE NORTH OF THE FORECAST AREA. A
BETTER CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED NEXT
WORK WEEK.

&&

.DISCUSSION...A GENERALLY FAIR WEATHER PATTERN WILL CONTINUE TO
PREVAIL TONIGHT INTO THE WEEKEND AS TROUGH ALOFT CONTINUES TO MOVE
AWAY FROM THE LOCAL AREA. AS AFOREMENTIONED TROUGH MOVES TO THE
EAST...A WEAK MID LEVEL RIDGE WILL CONTINUE TO BUILD FROM THE
WEST. AT LOW LEVELS...LOCAL PRESSURE GRADIENT WILL TIGHTEN AS
HIGH BUILDS AND RELOCATES TO THE NORTH OF THE FORECAST AREA.

AS RESULT...FOR THE NEXT TWO DAYS OR SO...UNDER THE PREVAILING
WIND FLOW...EXPECT PASSING SHOWERS EMBEDDED IN THE TRADES ACROSS
THE EAST COASTAL SECTIONS OF THE ISLANDS ESPECIALLY DURING THE
MORNING HOURS...FOLLOWED BY AFTERNOON CONVECTION WHICH WILL BE
MAINLY FOCUSED ACROSS WESTERN PUERTO RICO DUE TO DIURNAL HEATING
AND LOCAL EFFECTS.

FOR THE UPCOMING WORK WEEK...A HIGHER AMPLITUDE TROUGH IS FORECAST
TO EXTEND FROM THE BAHAMAS INTO THE WESTERN CARIBBEAN...WITH
DIVERGENT SIDE OF ASSOCIATED JET OVER THE AREA. THIS WILL BRING
DEEP MOISTURE AND FAVORABLE UPPER LEVEL DYNAMICS OVER PUERTO RICO
AND U.S. VIRGIN ISLANDS...RESULTING IN CLOUDY AND WET CONDITIONS
WITH A GOOD CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY ESPECIALLY
THE MIDDLE/LATTER PART OF NEXT WEEK.


&&

.AVIATION...VFR CONDITIONS EXPECTED ACROSS THE LOCAL TERMINALS
THROUGH THE FORECAST PERIOD WITH THE EXCEPTION OF TJMZ AND THE
VICINITY OF TJBQ WHERE SHRA/TSRA MAY CAUSE MVFR/IFR CONDITIONS UNTIL
AROUND 18/22Z. EASTERLY WINDS WITH SEA BREEZE VARIATIONS AT AROUND
10 TO 15 KTS GUSTING TO 25KTS UNTIL 18/00Z...BECOMING LIGHTER
THEREAFTER.

&&

.MARINE...LOCAL PRESSURE GRADIENT WILL TIGHTEN DURING THE WEEKEND
AS SURFACE HIGH BUILDS AND RELOCATES TO THE NORTH OF THE FORECAST
AREA. SEAS UP TO 5 FEET AND WINDS UP TO 21 KNOTS EXPECTED FOR
THE NEXT FEW DAYS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 77 87 77 87 / 10 20 20 20
STT 76 88 76 88 / 10 10 30 30

[cycloneye]

The models continue to show a very rainy pattern starting early next week and it may last until just after the last weekend of May. Stay tuned for more details about this as they become available.

[cycloneye]

Good morning. A good weekend weatherwise is on tap for PR and adjacent islands but things turn rainy by next week so stay tuned.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
510 AM AST SAT MAY 18 2013

.SYNOPSIS...STRENGTHENING SURFACE HIGH PRESSURE ACROSS THE NORTH
CENTRAL ATLANTIC AND JUST NORTH OF THE REGION WILL MAINTAIN A
DOMINANT EASTERLY TRADE WIND FLOW ACROSS THE NORTHEASTERN CARIBBEAN
FOR THE NEXT SEVERAL DAYS. MID TO UPPER LEVEL TROUGH CONTINUED TO
SHIFT EAST NORTHEAST OF AREA. MEANWHILE MID TO UPPER RIDGE EXTENDS
NORTHWARDS ACROSS THE REGION FROM THE CARIBBEAN BASIN. THIS OVERALL
PATTERN WILL MAINTAIN PREVAILING UPPER LEVEL WESTERLIES THROUGH AT
LEAST THE MIDDLE OF THE UPCOMING WEEK.

&&

.DISCUSSION...PREVIOUS TJSJ 19/00Z UPPER AIR SOUNDING AS WELL AS
SAT AND GPS DERIVED PWAT/IPW ANALYSIS PRODUCTS ALL SUGGEST A
GRADUAL DYING TREND DURING THE PAST 24 HOURS WITH ONLY SHALLOW
PATCHES OF LOW LEVEL MOISTURE MOVING ACROSS THE REGIONAL WATERS.
LATEST SATELLITE IMAGERY ALSO SHOWED LESSER CLOUD COVER/MOISTURE
COMPARED TO RECENT DAYS...WITH SUBTROPICAL JET AXIS NOW RELOCATED
EAST OF THE REGION AND OVER THE LESSER ANTILLES. THIS IS PLACED
THE FORECAST AREAS IN A FAIRLY DRY AND SUBSIDENT PATTERN ALOFT.
EXPECT FAIR AMOUNTS OF SUNSHINE TODAY WITH SOME DIURNALLY INDUCED
SHOWER DEVELOPMENT POSSIBLE MAINLY ACROSS PARTS OF THE CENTRAL
AND WEST INTERIOR SECTIONS OF PUERTO RICO. ACTIVITY SHOULD HOWEVER
BE OF SHORT DURATION AND NOT WIDESPREAD AMOUNTS OF RAINFALL. BY
LATE SUNDAY AND INTO MONDAY A SECONDARY SHORT WAVE SHOULD MOVE
JUST NORTH OF THE REGION. HOWEVER NO SIGNIFICANT AMOUNTS OF MOISTURE
ADVECTION IS APPARENT AT THIS TIME...AS THE UPPER LEVEL WINDS CONTINUE
TO SHEAR THE CONVECTION ACROSS THE TROPICAL ATLANTIC AND MAINTAIN
MOST OF TROPICAL MOISTURE SOUTH OF THE REGION.

BY MID WEEK HOWEVER AND FOR THE REST OF THE UPCOMING WEEK LOOK
FOR INCREASING MOISTURE AS LONG WAVE TROUGH WEST OF THE REGION
SHOULD BECOME SLIGHTLY AMPLIFIED WEST OF THE AREA. THIS SHOULD
LIFT ADDITIONAL TROPICAL MOISTURE NORTHWARDS ACROSS THE REGION.
LATEST GFS MODEL CONTINUED TO SUGGEST PWAT VALUES TO INCREASE TO
TWO INCHES OR MORE BY THURSDAY AND INTO THE FOLLOWING WEEKEND. THE
COMBINATION OF THE AMPLIFYING UPPER TROUGH AND INCREASING MOISTURE
WILL MAKE CONDITIONS MORE FAVORABLE AND UNSTABLE...THUS RESULTING IN
BETTER CHANCE FOR ENHANCED CONVECTIVE DEVELOPMENT DURING THE LATTER
PART OF THE WEEK.

&&

.AVIATION...MOSTLY VFR COND ARE EXPECTED AT ALL TAF SITES UNTIL
18/16Z. MVFR/PSBL BRIEF IFR CONDS WILL REMAIN LIKELY BETWEEN
18/17Z-18/21Z ALONG THE CORDILLERA CENTRAL AND ACROSS TJMZ IN AREAS
OF +SHRA/TSRA. MTN TOPS MAY BE OBSCURED OVER WRN INTERIOR OF PR. FOR
THE NORTHERN LEEWARD ISLANDS...MAINLY VFR CONDS ARE EXPECTED.
PREVIOUS 18/ 00Z TJSJ SOUNDING INDICATES MAINLY EAST WINDS AT 20
KNOTS OR LESS UP TO 3 KFT...BECOMING LIGHT AND VARIABLE BTW 3-20KFT
AND THEN NORTHWESTERLY AND STRONGER ALOFT.


&&

.MARINE...FAIRLY TRANQUIL SEAS OVERALL FOR THE NEXT SEVERAL DAYS...WITH
SEAS MAINLY 5 FEET OR LESS TODAY. EASTERLY TRADE WINDS WILL GRADUALLY
INCREASE BY MID WEEK AS PREVIOUSLY MENTIONED SURFACE PRESSURE
GRADIENT TIGHTENS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 76 87 77 / 20 20 20 20
STT 86 76 87 78 / 10 30 30 30

[cycloneye]

Code: Select all

JAMAICA WEATHER

 LOCAL FORECAST

May 18 2013
 

Significant Feature: A surface trough across the central Caribbean.

Morning:  Mainly fair.

Afternoon:  Partly cloudy with scattered showers mainly over central and western parishes.

Tonight: Fair.

Winds:  Will reach in excess of 10 knots (12 mph)

Temperatures: High: 31C (88F)     Low: 25C (77F)