Caribbean - Central America Weather

[Macrocane]

It has been 3 weeks without a cold front in Central America (an unusually long period for December and January) but this one looks healthy:



The HPC discussion:

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
153 PM EST WED JAN 16 2013

DISCUSSION FROM JAN 16/00UTC: LONG WAVE POLAR TROUGH OVER NORTH
AMERICA CONTINUES TO PRESS EAST INTO THE CENTRAL PLAINS...AND
THROUGH 42/48 HRS IT IS TO REACH THE EASTERN USA WHERE IT IS TO
THEN LIFT OVER A WANING RIDGE. ASSOCIATED SURFACE FRONT IS RACING
ACROSS THE GULF OF MEXICO...AND UNDER INFLUENCE OF A 30-35KT
NORTHERLY SURGE IT IS TO PUSH ACROSS THE FLORIDA PANHANDLE TO
CAMPECHE/TABASCO-OAXACA IN SOUTHERN MEXICO BY 24 HRS. THROUGH 36
HRS IT WILL MOVE ACROSS THE YUCATAN TO GUATEMALA...WITH A 50KT
TEHUANTEPECER JET ESTABLISHING OVER THE EASTERN PACIFIC. THROUGH
48-60 HRS THE FRONT MOVES INTO THE NORTHWEST BAHAMAS-WESTERN
CUBA-GULF OF HONDURAS/GUATEMALA. NORTHERLY WINDS OF 25-30KT ARE TO
ACCOMPANY THIS FRONT AS IT ENTERS THE WESTERN CARIBBEAN. BY 72 HRS
IT WILL MOVE TO CENTRAL BAHAMAS/CENTRAL CUBA WHILE TRAILING ACROSS
THE NORTHWEST CARIBBEAN. LATER IN THE CYCLE THE FRONT WILL START
TO RETROGRESS. FURTHERMORE...A SHORT LIVED PREFRONTAL SHEAR LINE
IS TO FORM AHEAD OF THIS BOUNDARY BY 54-78/84 HRS...TO EXTEND
ACROSS EASTERN CUBA-JAMAICA TO NICARAGUA.

AS THE FRONT SURGES ACROSS THE SOUTHERN STATES OF MEXICO EARLY
THIS CYCLE IT WILL SUSTAIN RAINFALL AMOUNTS 20-30MM/DAY AND MAXIMA
OF 75-150MM/DAY. BY 48-60 HRS THIS WILL DECREASE TO 15-20MM/DAY
AND MAXIMA OF 30-60MM. ACROSS GUATEMALA EXPECTING RAINFALL AMOUNTS
OF 15-30MM/DAY AND MAXIMA OF 40-80MM BY 18-42 HRS. OVER THE
NORTHWEST CARIBBEAN TO NORTHERN HONDURAS...EXPECTING RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 30-60MM/DAY BY 24-48
HRS...AND 20-40MM/DAY AND MAXIMA OF 75-125MM/DAY BY 48-108 HRS.
DURING THAT PERIOD...LOCALIZED MAXIMA OF 150-200MM ARE HIGHLY
LIKELY DUE TO STRONG LOW LEVEL CONVERGENCE. OVER WESTERN-CENTRAL
CUBA THE FRONTAL CONVECTION WILL SUSTAIN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM/DAY...WHILE OVER NORTHWEST
BAHAMAS EXPECT ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15MM.
OVER THE CAYMAN ISLANDS EXPECTING ACCUMULATION OF 05-10MM/DAY AND
MAXIMA OF 15MM. THROUGH 72-84 HRS THE MAXIMA WILL INCREASE TO
20-30MM. SHEAR LINE CONVERGENCE ACROSS EASTERN CUBA WILL SUSTAIN
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM...WHILE ACROSS
EASTERN NICARAGUA EXPECT ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF
20-30MM.

MID/UPPER LEVEL RIDGE OVER THE WESTERN ATLANTIC/EASTERN USA IS
YIELDING TO PROGRESSIVE POLAR TROUGH STREAMING ACROSS NORTH
AMERICA. THROUGH 48-60 HRS THE MID LEVEL RIDGE IS TO REPOSITION TO
THE NORTH-NORTHEAST OF THE LEEWARD ISLANDS...AND BY 72-96 HRS IT
IS TO SETTLE OVER THE CENTRAL ATLANTIC. AS THE RIDGE PATTERN
RELOCATES...SUBSIDENCE/TRADE WIND CAP ACROSS SOUTHERN
MEXICO-NORTHERN CENTRAL AMERICA IS FORECAST TO WEAKEN. OVER THE
CENTRAL AND EASTERN CARIBBEAN...THE SUBSIDENCE CAP WILL BE
STRONGER AND MORE RESILIENT AND IN THIS AREA IT IS TO CONTINUE
INHIBITING DEEP CONVECTION. A TUTT BOUNDS THE SOUTHERN FRINGES OF
THE UPPER LEVEL RIDGE...WITH AXIS ACROSS THE GREATER ANTILLES TO A
CLOSED LOW OVER THE WESTERN CARIBBEAN. AS THE RIDGE MEANDERS
EAST...THE TROUGH WILL CUT OFF...THEN START TO WEAKEN/FILL AS IT
LIFTS NORTH ACROSS CUBA BY 48 HRS. ALTHOUGH IT TENDS TO
WEAKEN...COLD CORE FEATURE IS LIKELY TO ENHANCE VENTILATION ALOFT
WHILE FAVORING A CONVECTIVELY UNSTABLE AIR MASS. BEST INSTABILITY
IS EXPECTED ACROSS EASTERN NICARAGUA/WESTERN CARIBBEAN EARLY IN
THE CYCLE...AND CENTRAL/WESTERN CUBA BY 30-42 HRS. AS IT ENHANCES
INSTABILITY ACROSS CUBA-THE CAYMAN ISLES AND NORTHERN VENEZUELA
THIS WILL RESULT AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM.

AT LOW LEVELS IT REFLECTS AS A BROAD RIDGE OVER THE WESTERN
ATLANTIC AND TO THE NORTH OF THE ISLANDS. THIS RIDGE IS TO ALSO
MOVE TO THE CENTRAL ATLANTIC BY 36-48HRS...AND FURTHER EAST LATER
IN THE CYCLE. AS IT PULLS AWAY...AND THE GRADIENT SLACKENS...
TRADES ACROSS THE EASTERN AND NORTHERN CARIBBEAN WILL DECREASE TO
10-15KT. WINDS ARE TO ALSO VEER TO THE EAST-NORTHEAST LATER
TODAY...AND TO THE EAST-SOUTHEAST DURING THE WEEKEND. ALTHOUGH
FLOW PATTERN CHANGES...MOIST ADVECTION WILL PERSIST ACROSS THE
EASTERN CARIBBEAN ISLANDS...WITH TRADE WIND SHOWERS TO PESTER THE
THESE ISLES. ACROSS THE ISLAND CHAIN-NORTHERN CARIBBEAN ISLES
EXPECTING RAINFALL AMOUNTS OF 00-05MM/DAY AND WIDELY ISOLATED
MAXIMA OF 10MM. OVER EASTERN NICARAGUA/NORTHEAST HONDURAS
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-25MM/DAY.

EAST OF THE WESTERN ATLANTIC RIDGE...OVER THE CENTRAL-EASTERN
ATLANTIC...A TROUGH EXTENDS BETWEEN 50W-30W TO NORTHERN BRASIL-THE
GUIANAS. AS THE RIDGE RELOCATES INTO THE CENTRAL ATLANTIC...THE
TROUGH IS TO CUT OFF FROM THE MEAN FLOW...AND BY 42-48 HRS IT WILL
START TO FILL/WEAKEN. MEANWHILE...AS IT HOLDS OVER THE CENTRAL
ATLANTIC...IT IS TO INTERACT WITH THE ITCZ...PROVIDING THE
VENTILATION ALOFT THAT IS TO ENHANCE CONVECTIVE DEVELOPMENT ALONG
THE CONVERGENCE ZONE. THIS IS TO ALSO ENHANCE DIURNAL CONVECTION
ACROSS THE NORTHERN GUIANAS WHERE WE EXPECT RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-20MM/DAY. THROUGH 48 HRS THIS WILL
DECREASE TO 05-10MM/DAY AND MAXIMA OF 15MM.

OVER THE EASTERN PACIFIC...THE ITCZ MEANDERS INLAND OVER COLOMBIA
BETWEEN THE EJE CAFETERO TO THE NORTH AND THE CAUCA VALLEY TO THE
SOUTH. IN THIS AREA EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-35MM/DAY. THROUGH 72-96 HRS THIS WILL DECREASE TO
05-10MM/DAY AND MAXIMA OF 15MM. OVER EJE CAFETERO TO THE
NORTH...EXPECT ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15-20MM.

ALVAREZ...ONAMET (REPUBLICA DOMINICANA)
GALDAMEZ...DGOA-MARN (EL SALVADOR)
DAVISON...HPC (USA)

[cycloneye]

Good morning.


AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
412 AM AST THU JAN 17 2013

.SYNOPSIS...UPPER LEVEL RIDGE WILL YIELD TO WEAKENING UPPER LEVEL
TROF LIFTING NE FROM THE NW CARIBBEAN. AS UPPER LEVEL TROF LIFTS
NORTHEAST OF THE AREA RIDGE THEN BUILDS AGAIN OVER THE WEEKEND
BEFORE FLATTENING MID NEXT WEEK AS POLAR TROUGH DEEPENS ACROSS THE
WRN ATLC.

&&

.DISCUSSION...MODELS GENERALLY MAINTAIN STRONG MID-UPPER LEVEL
RIDGE PATTERN AND ASSOCIATED SUBSIDENCE INVERSION THROUGH THE NEXT
SEVEN DAYS WITH SOME WEAKENING OF THE RIDGE FCST MID NEXT WEEK.
MODELS TODAY SHOW MUCH LESSER LOW LEVEL RH VALUES AND WEAKER LOW
LEVEL LAPSE RATES THAT SHOULD RESULT IN A LOT MORE SUN THAN
CLOUDS...SLIGHTLY WARMER TEMPS AND FAR FEWER SHOWERS. CLOUDS AND
EMBEDDED LIGHT SHOWERS WILL RETURN OVERNIGHT AND FRI YIELDING
SIMILAR CONDITIONS TO THOSE EXPERIENCED YESTERDAY. SOME
IMPROVEMENT IS EXPECTED OVER THE WEEKEND AS RIDGE BUILDS AGAIN BUT
THE IMPROVEMENT WILL BE MORE NOTICEABLE EARLY NEXT WEEK AS WINDS
VEER MORE THE EAST SOUTHEAST SUPPORTING MUCH WARMER TEMPERATURES.
WINDS WILL DIMINISH CONSIDERABLY NEXT WEEK AS A COL REGION
DEVELOPS NORTH OF THE AREA WEAKENING THE PRES GRADIENT. AS UPPER
LEVEL RIDGE WEAKENS AND WINDS DIMINISH NEXT WEEK THIS MAY ALLOW
FOR SLIGHTLY BETTER CHANCES OF SEA BREEZE RELATED CONVECTION.

&&

.AVIATION...VFR CONDITIONS WILL CONTINUE TO PREVAIL AT ALL TAF SITES
THROUGH THE FORECAST PERIOD WITH EAST NORTHEAST WINDS BETWEEN 10 TO
15 KTS.


&&

.MARINE...AFTER ALMOST TWO WEEKS OF UNINTERRUPTED SMALL CRAFT
ADVZY CONDITIONS SEAS WILL FINALLY DROP BELOW 7 FT BY THIS
EVENING. FURTHER IMPROVEMENT IS EXPECTED OVER THE WEEKEND AS WINDS
DROP TO 15 KT OR LESS YIELDING SEAS 3 TO 5 FT. A SMALL NORTH SWELL
EVENT WILL BEGIN TO AFFECT THE ATLC WATERS ON MARTIN LUTHER KING
JR DAY RAISING SEAS TO 6 FT.


&&

.FIRE WEATHER...STILL BREEZY TODAY WITH WARMER TEMPS AND LOWER RHS
DUE TO SIG MORE BREAKS IN THE CLOUD CVR THAN YDAY. CLOUDY AGAIN
FRI WITH MORE SUNSHINE SAT AND SUN. WINDS WILL DIMINISH
CONSIDERABLY OVER THE WEEKEND AND NEXT WEEK TO LESS THAN 15 MPH.
ANY SHOWERS WILL ONLY LEAVE TRACE OR VERY LIGHT AMOUNTS MAINLY
FRI.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 80 72 80 72 / 20 20 20 10
STT 82 74 82 74 / 20 20 10 10

[cycloneye]

January 17 Jamaica forecast:

Code: Select all

Significant Feature: High pressure ridge over the northern Caribbean.

Morning: Mainly fair.

Afternoon: Partly cloudy with isolated showers over sections of the island.

Tonight: Fair.

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

Temperatures: High: 31C (88F)     Low: 23C (73F)

 

Location
 Sunrise
 Sunset
 
Kingston
 6:42 a.m.
 5:53 p.m.
 
Montego Bay
 6:47 a.m.
 5:58 p.m.
 
Negril
 6:48 a.m.
 5:59 p.m.
 


[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
246 PM AST THU JAN 17 2013

.SYNOPSIS...HIGH PRESSURE RIDGE OVER THE REGION IS EXPECTED TO
MAINTAIN A STRONG SUBSIDENCE INVERSION PATTERN ACROSS THE LOCAL
ISLANDS THROUGH THE NEXT SEVERAL DAYS.

&&

.DISCUSSION...ISOLATED TO LOCALLY SCATTERED PASSING SHOWERS AFFECTED
THE EASTERN SECTIONS OF PUERTO RICO AS WELL AS VIEQUES...CULEBRA AND
THE USVI DURING THE MORNING HOURS. THIS ACTIVITY DISSIPATED RAPIDLY
BY MID MORNING HOURS...LEAVING ONLY CLEAR TO PARTLY CLOUDY SKIES
WITH LIMITED SHOWER ACTIVITY ACROSS THE REGION. STRONG HIGH PRESSURE
SYSTEM AT ALL LEVEL OF THE ATMOSPHERE...JUST NORTH OF THE AREA...IS
EXPECTED TO MAINTAIN STRONG SUBSIDENCE INVERSION AND THUS A
GENERALLY FAIR WEATHER PATTERN...WITH VERY LOW PWAT VALUES ACROSS
THE REGION FOR THE NEXT SEVERAL DAYS. HOWEVER...LATEST SATELLITES
IMAGES THIS AFTERNOON DEPICTED SMALL PATCHES OF LOW LEVEL MOISTURE
EMBEDDED IN THE HIGH PRESSURE CIRCULATION. SOME OF THESE PATCHES OF
MOISTURE WILL MOVE ONSHORE ACROSS NORTHERN AND EASTERN PUERTO
RICO...PRODUCING ISOLATED PASSING SHOWERS ACROSS THE LOCAL ISLANDS
MAINLY DURING THE NIGHT AND EARLY MORNING HOURS. NO SIGNIFICANT
CHANGES ARE EXPECTED IN THE PRESENT WEATHER PATTERN UNTIL MID NEXT
WEEK. WIND WILL CONTINUE MAINLY FROM THE EAST THROUGH THE REST OF
THE WEEK AND SLIGHTLY DIMINISHING.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS. A FEW
PASSING SHOWERS MAY CAUSE BRIEF MOMENTS OF MVFR CONDITIONS AS THE
SHOWERS PASS BY. WINDS WILL BE MAINLY FROM THE EAST AT 10 TO 15
KNOTS WITH A FEW HIGHER GUSTS UNTIL ABOUT 17/23Z. THEREAFTER...WINDS
WILL REMAIN FROM THE EAST BUT WILL DECREASE IN SPEED.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 73 80 71 80 / 20 20 10 10
STT 73 82 74 82 / 20 10 10 20

[Macrocane]

And the cold finally arrived

EPAC TWD:

BASED ON PREVIOUS SCATTEROMETER PASSES...N TO NE WINDS OF 35-50
KT ARE FUNNELING THROUGH THE GULF OF TEHUANTEPEC. EXPECT THE
CULPRIT VERY TIGHT PRES GRADIENT TO PERSIST THROUGH THE NEXT
FEW DAYS WHILE IT BEGINS TO GRADUALLY WEAKEN. THIS WILL BRING
THESE WINDS UP STORM FORCE ACROSS THE GULF THROUGH FRI
MORNING...GALE FORCE WINDS THROUGH SUN MORNING THEN VERY STRONG
TO NEAR-GALE CONDITIONS THROUGH TUE WITH PEAK WINDS REACHING
MINIMAL GALE AROUND SUNRISE FROM DIURNAL EFFECTS. NO SIGNIFICANT
CHANGE IS EXPECTED IN THE SYNOPTIC PATTERN...WITH NORTHERLY
WINDS IN THE GULF OF MEXICO AND PERSISTENT STRONG PRES GRADIENT
IN CENTRAL AMERICA. THE GULF OF PAPAGAYO WILL ALSO BEGIN TO
EXPERIENCE STRONG PERSISTENT NE WINDS FRI THROUGH MON IN THIS
SYNOPTIC PATTERN. FRESH TO STRONG E-NE WINDS WILL EXTEND FAR
DOWNWIND FROM THE SOURCE REGIONS NEAR TEHUANTEPEC AND GULF OF
PAPAGAYO...RESULTING IN VERY LARGE AREA OF ELEVATED SEA HEIGHTS
IN NE SWELL THU THROUGH LATE SAT EXTENDING ROUGHLY FROM 05N TO
14N E OF 107W. N TO NE WINDS OF 20-25 KT ARE FORECAST TO SURGE
THROUGH THE GULF OF PANAMA BEGINNING FRI EVENING AND CONTINUE
INTO EARLY NEXT WEEK.

HPC Discussion

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
205 PM EST THU JAN 17 2013

DISCUSSION FROM JAN 17/00UTC: AMPLIFYING POLAR TROUGH DOMINATES
NORTH AMERICA...AND THROUGH 36-48 HRS IT WILL EXPAND INTO THE
WESTERN ATLANTIC...TO THEN EVOLVE INTO A LOW AMPLITUDE TROUGH.
AXIS IS TO THEN PERSIST BEYOND 72-96 HRS. ASSOCIATED SURFACE FRONT
PUSHES ACROSS SOUTH FLORIDA-WESTERN CUBA TO QUINTANA ROO
MEXICO/BELIZE BY 24 HRS...STRONG NORTHERLIES ACROSS THE GULF WILL
SUSTAIN A 50KT TEHUANTEPECER JET OVER THE EASTERN PACIFIC. THROUGH
36 HRS THE FRONT MOVES INTO THE NORTHWEST BAHAMAS-WESTERN
CUBA-GULF OF HONDURAS/GUATEMALA. NORTHERLY WINDS OF 25-30KT ARE TO
ACCOMPANY THIS FRONT AS IT ENTERS THE WESTERN CARIBBEAN. BY 48 HRS
IT WILL MOVE TO CENTRAL BAHAMAS/CENTRAL CUBA WHILE TRAILING ACROSS
THE NORTHWEST CARIBBEAN/GULF OF HONDURAS. BY 60-72 HRS THE TAIL
END OF THE FRONT OVER THE WESTERN CARIBBEAN STARTS TO WEAKEN AS IT
RETROGRESS. BY 84-96 HRS THE WANING FRONT IT IS TO THEN ALIGN
ACROSS THE NORTHWEST BAHAMAS-SOUTH FLORIDA TO THE GULF OF MEXICO.
ALTHOUGH FRONT PULLS AWAY...NORTHEASTERLY WINDS OF 15-20KT ARE TO
PERSIST ACROSS THE WESTERN CARIBBEAN TO NORTHERN CENTRAL AMERICA.
FURTHERMORE...A SHEAR LINE IS TO DEVELOP AHEAD OF THIS FRONT...AND
BY 24-30 HRS IT IS TO EXTEND ACROSS CENTRAL CUBA TO EASTERN
NICARAGUA. BY 36-42 HRS IT IS TO MEANDER ACROSS EASTERN
CUBA-JAMAICA-EASTERN NICARAGUA...TO BECOME ILL DEFINED BY 54-60
HRS.

POST FRONTAL NORTHERLIES WILL SUSTAIN SCATTERED CONVECTION ACROSS
THE SOUTHERN STATES OF CHIAPAS-TABASCO-CAMPECHE...WITH RAINFALL
AMOUNTS OF 15-30MM/DAY AND MAXIMA OF 50-100MM/DAY THROUGH 30-36
HRS...AND 10-15MM/DAY AND MAXIMA OF 20-40MM BY 36-60 HRS. ACROSS
GUATEMALA EXPECTING RAINFALL AMOUNTS OF 15-30MM/DAY AND MAXIMA OF
40-80MM THROUGH 30-36 HRS. OVER THE NORTHWEST CARIBBEAN TO
NORTHERN HONDURAS EXPECTING RAINFALL AMOUNTS OF 15-30MM/DAY AND
MAXIMA OF 40-80MM/DAY BY 24-36 HRS...AND 25-50MM/DAY AND MAXIMA OF
100-150MM/DAY BY 24-60 HRS. AT 60-84 HRS EXPECT RAINFALL AMOUNTS
OF 20-40MM/DAY AND MAXIMA OF 75-125MM...WITH MAXIMA OF 40-80MM
LATER ON DAY 04. OVER WESTERN-CENTRAL CUBA THE FRONTAL CONVECTION
WILL SUSTAIN RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF
20-35MM/DAY...WHILE OVER NORTHWEST BAHAMAS EXPECT ACCUMULATION OF
05-10MM/DAY AND MAXIMA OF 15MM. MODELS AGREE ON PERSISTENT SHOWERS
ACROSS THE NORTHWEST BAHAMAS THROUGH DAY 04. OVER THE CAYMAN
ISLANDS EXPECTING ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15MM.
SHEAR LINE CONVERGENCE ACROSS EASTERN CUBA WILL SUSTAIN RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM...WHILE ACROSS EASTERN
NICARAGUA EXPECT ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF
20-30MM. OVER JAMAICA EXPECTING ACCUMULATION OF 00-05MM/DAY AND
MAXIMA OF 10MM WITH THIS FEATURE.

MID/UPPER LEVEL RIDGE OVER THE WESTERN ATLANTIC CONTINUES TO YIELD
TO POLAR TROUGH OVER NORTH AMERICA. AS POLAR TROUGH EXPANDS TO THE
WESTERN ATLANTIC...THE RIDGE WILL THEN CONFINE TO THE CENTRAL
TROPICAL ATLANTIC AND THE EASTERN-CENTRAL CARIBBEAN. ALTHOUGH
UPPER PATTERN EVOLVES...MODELS CONTINUE TO SUSTAIN A TRADE WIND
CAP ACROSS THE EASTERN CARIBBEAN ISLANDS. THIS WILL CAP MOISTURE
TO THE LOWER ATMOSPHERE...WITH PWAT DURING THE NEXT FEW DAYS TO
RANGE BETWEEN 25-30MM. A TUTT TO THE WEST IS LIFTING ACROSS
CUBA/THE BAHAMAS...AND THROUGH 30-36 HRS IT IS TO ACCELERATE AS IT
LIFTS AROUND THE RECEDING UPPER RIDGE PATTERN. MEANWHILE...THIS IS
TO ENHANCE INSTABILITY ACROSS PORTIONS OF CENTRAL AMERICA-CUBA
WHILE ALSO PROVIDING VENTILATION ALOFT IN SUPPORT OF DEEP
CONVECTION.

AS THE LOW/MID LEVEL RIDGE ROLLS AWAY...AND GRADIENT SLACKENS...
EASTERLY TRADES HAVE STARTED TO VEER WHILE DECREASING IN
INTENSITY. THIS IS TO THEN FAVOR A LONG FETCH OF EASTERLY TRADES
ACROSS THE TROPICAL ATLANTIC INTO THE EASTERN-CENTRAL CARIBBEAN.
THIS IS TO CONTINUE FAVORING GENERATION OF TRADE WIND
SHOWERS...WITH THE OCCASIONAL CLOUD CLUSTER TO AFFECT THE ISLAND
CHAIN-NORTHEAST CARIBBEAN ISLES. IN THIS AREA EXPECTING RAINFALL
AMOUNTS OF 00-05MM/DAY AND MAXIMA OF 10MM/DAY. OVER EASTERN
NICARAGUA/NORTHEAST HONDURAS EXPECTING TRADES TO CONVERGE ON THE
CARIBBEAN COASTAL PLAINS...TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-20MM/DAY ON DAY 01 AND AGAIN ON DAY
04. HIGHER AMOUNTS ON DAYS 02-03 WILL ASSOCIATE WITH PREFRONTAL
SHEAR LINE (SEE ABOVE).

A WANING MID/UPPER TROUGH LIES EAST OF THE WESTERN ATLANTIC RIDGE.
MID/UPPER TROUGH TRAILS TO THE SOUTH-SOUTHWEST ALONG 30N 30W TO
10N 50W. THIS IS INTERACTING WITH THE ITCZ...VENTING DEEP
CONVECTION ACROSS THE CENTRAL TROPICAL ATLANTIC. BEST MOISTURE
CONVERGENCE...HOWEVER...IS ALONG THE NEAR EQUATORIAL TROUGH AS IT
MEANDERS INLAND ACROSS AMAPA/AMAZON RIVER DELTA IN BRASIL. ACROSS
THE NORTHERN GUIANAS...LIGHT SEA BREEZE CONVERGENCE IS TO
GENERALLY RESULT IN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15MM/DAY.

OVER THE EASTERN PACIFIC...MODELS SHOW A NEGATIVELY TILTED UPPER
TROUGH EXTENDING ALONG PACIFIC COAST OF CENTRAL AMERICA. THROUGH
36-48 HRS THE TROUGH WILL EXPAND TO THE SOUTHEAST TOWARD
COLOMBIA/ECUADOR...IN THIS PROCESS DRAWING A JET MAXIMA NORTH
ACROSS ECUADOR/SOUTHERN COLOMBIA. THE UPPER TROUGH AND JET MAXIMA
WILL ENHANCE VENTILATION ALOFT...ALLOWING FOR DEEP MOISTURE TO
POOL ACROSS THE WESTERN PLAINS AND ANDEAN REGION OF COLOMBIA. IN
THIS AREA EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM/DAY. THROUGH 60-84 HRS THIS WILL INCREASE TO 15-30MM.

[cycloneye]

Good morning. After a few weeks of cooler temperatures,a warming trend will start by early next week.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
413 AM AST FRI JAN 18 2013

.SYNOPSIS...SHORTWAVE-TROUGH ACROSS THE SW ATLC WILL LIFT NE TODAY WITH
UPPER RIDGE AXIS EXPECTED TO BUILD WWD OVR LOCAL AREA OVERNIGHT.
RIDGE WILL HOLD THROUGH THE WEEKEND THEN START TO WEAKEN NEXT WEEK
AS POLAR TROUGH DEEPENS ACROSS ERN NOAM.

&&

.DISCUSSION...A CLOUDY SHOWERY DAY APPEARS ON TAP FOR TODAY AS A
WEAK SFC TROF/TRADE WIND SURGE MOVE ACROSS. MUCH DRIER AIR WILL
WORK INTO THE USVI BY THIS AFTERNOON AND ACROSS PR BY MIDNIGHT AS
UPPER RIDGE AXIS BUILDS OVR THE AREA AGAIN. UPPER RIDGE AXIS HOLDS
THROUGH THE WEEKEND BUT SINCE LOW LEVEL LAPSE RATES REMAIN STEEP
AND LOW LEVEL RH`S HIGH EXPECT TO SEE CONSIDERABLE CLOUDS WITH
STILL THE RISK OF ISOLATED SHOWERS.

UPPER LEVEL RIDGE WILL GRADUALLY YIELD TO DEEPENING POLAR TROUGH
PATTERN ACROSS ERN NOAM NEXT WEEK. HOWEVER MID LEVEL RIDGE IS
EXPECTED TO HOLD OVR MUCH OF THE WEEK SUSTAINING SUBSIDENCE
INVERSION. ANOTHER FEATURE OF INTEREST IS DEEP CUTOFF LOW ACROSS
THE CNTRL TROP ATLC. GLOBAL MODELS SHOW MID LEVEL REFLECTION
RETROGRADING TOWARD FCST AREA BUT WEAKENING THROUGH TIME AS IT
MOVES UNDERNEATH MID LEVEL RIDGE. ATTM IT APPEARS FCST AREA WILL
REMAIN IN THE SUBSIDENT SIDE OF THIS FEATURE WITH NO IMPACTS TO
OUR AREA. SINCE A GENERAL SUBSIDENT PATTERN IS EXPECTED TO HOLD
OVR THE NEXT SEVEN DAYS PRECIP CHANCES ARE EXPECTED TO REMAIN LOW.

MAIN CHANGES TO LOCAL WEATHER PATTERN OVR THE NEXT SEVEN DAYS ARE
A DIMINISHING TREND IN WINDS EARLY NEXT WEEK AS A COL REGION
DEVELOPS NORTH OF THE AREA AND A GRADUAL WARMING TREND DUE TO
ADIABATIC WARMING UNDERNEATH MID LEVEL RIDGE AND EAST SOUTHEAST
WINDS. 1000-850 MB THICKENESSES SUGGEST TEMPS COULD APPROACH 90F
ON THE NORTH COAST ON TUE. THE WARMING TREND WILL BE MORE
NOTICEABLE AT HIGHER ELEVATIONS.

&&

.AVIATION...ALTHOUGH CIGS ARE EXPECTED TO REMAIN MAINLY VFR...BKN-
OVC CIGS 030-050 ARE EXPECTED ACROSS PR TERMINALS TODAY. WINDS
WILL BE EAST NORTHEAST WINDS BETWEEN 10 TO 15 KTS WITH ISOLATED TO
SCATTERED PASSING SHOWERS.

&&

.MARINE...SEAS EXPECTED TO DROP BELOW 6 FT TODAY AND REMAIN
GENERALLY 3-5 FT OVR THE WEEKEND AS WINDS SUBSIDE. A SMALL NORTH
SWELL WILL START AFFECTING THE ATLC COASTAL WATERS ON MARTIN
LUTHER KING JR DAY RAISING SEAS BRIEFLY TO 6 FT.

&&

.FIRE WEATHER...OVERCAST SKIES AND HIGHER HUMIDITIES TODAY WILL
HELP IN THE FIRE WEATHER SITUATION ACROSS THE SOUTH. CONSIDERABLE
CLOUDS SAT WITH DIMINISHING WINDS SUN AND MUCH OF NEXT WEEK. TEMPS
HOWEVER WILL BE ON THE RISE WITH 90F READINGS LIKELY LOWERING
HUMIDITIES.

&&

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



&&

[cycloneye]

January 18 Jamaica forecast:

Code: Select all

Significant Feature: Cold front over the western Caribbean.

Morning: Partly cloudy.

Afternoon: Windy with isolated showers over sections of the island.

Tonight: Fair.

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

Temperatures: High: 31C (88F)     Low: 23C (73F)

 

Location
 Sunrise
 Sunset
 
Kingston
 6:42 a.m.
 5:54 p.m.
 
Montego Bay
 6:47 a.m.
 5:59 p.m.
 
Negril
 6:48 a.m.
 6:00 p.m.
 


[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
246 PM AST FRI JAN 18 2013

.SYNOPSIS...HIGH PRESSURE RIDGE OVER THE REGION IS EXPECTED TO
MAINTAIN A GENERALLY FAIR WEATHER PATTERN ACROSS THE LOCAL ISLANDS
THROUGH THE WEEKEND.

&&

.DISCUSSION...ISOLATED TO LOCALLY SCATTERED PASSING SHOWERS AFFECTED
THE EASTERN SECTIONS OF PUERTO RICO AS WELL AS VIEQUES...CULEBRA AND
THE USVI DURING THE MORNING HOURS. EARLY IN THE AFTERNOON SHOWERS
DEVELOPED ACROSS WESTERN SECTIONS OF THE ISLAND...BUT THIS
ACTIVITY IS EXPECTED TO DISSIPATE LATE IN THE AFTERNOON OR EARLY
THIS EVENING. TODAY SHOWER ACTIVITY WAS THE RESULT OF A MOISTURE
SURGE ACROSS THE REGION. A GENERALLY FAIR WEATHER PATTERN IS
EXPECTED TO RETURN TO THE REGION TONIGHT. HIGH PRESSURE SYSTEM AT
ALL LEVEL OF THE ATMOSPHERE...JUST NORTHEAST OF THE AREA...IS
EXPECTED TO MAINTAIN A GENERALLY FAIR WEATHER PATTERN...WITH VERY
LOW PWAT VALUES ACROSS THE REGION THROUGH THE WEEKEND. HOWEVER...SMALL
AND SHALLOW PATCHES OF LOW LEVEL MOISTURE EMBEDDED IN THE HIGH
PRESSURE CIRCULATION WILL CONTINUE TO MOVE ACROSS THE REGION. SOME
OF THESE PATCHES OF MOISTURE WILL MOVE ONSHORE ACROSS EASTERN
PUERTO RICO...VIEQUES...CULEBRA AND THE USVI...FROM TIME TO TIME PRODUCING
ISOLATED PASSING SHOWERS ACROSS THE LOCAL ISLANDS MAINLY DURING
THE NIGHT AND EARLY MORNING HOURS. NO SIGNIFICANT CHANGES ARE
EXPECTED IN THE PRESENT WEATHER PATTERN UNTIL NEXT WEEK. WIND
WILL CONTINUE MAINLY FROM THE EAST SOUTHEAST THROUGH THE
WEEKEND...BECOMING MORE FROM THE SOUTHEAST BY MONDAY...SLIGHTLY
INCREASING THE TEMPERATURES ALONG NORTHERN COASTAL MUNICIPALITIES
OF PUERTO RICO.

&&

.AVIATION...MOSTLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST
PERIOD. TEMPO MVFR POSSIBLE ACROSS TJBQ AND TJMZ THIS AFTERNOON AS
SHRA MOVES WEST. WINDS WILL REMAIN FROM THE EAST AT AROUND 10 TO 15
KNOTS...DECREASING OVERNIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 82 72 83 / 10 10 20 20
STT 73 84 74 85 / 10 20 20 20

[Macrocane]

It has been a pretty cold and windy day in Central America:

ELSEWHERE AT THE SURFACE...A VERY TIGHT PRES GRADIENT ACROSS
CENTRAL AND SRN MEXICO INCLUDING THE ISTHMUS OF TEHUANTEPEC
CONTINUES TO BRING QUITE AN IMPRESSIVE SWATH OF STORM FORCE WIND
THROUGH THE CHIVELA PASS AND THROUGH THE GULF OF TEHUANTEPEC
AS WAS EVIDENT FROM SCATTEROMETER DATA FROM LAST NIGHT...AND
EARLY THIS MORNING. SHIP WITH CALL SIGN "3FCB8" SAILING TO THE
SE OVER THE SE PORTION OF THE GULF OF TEHUANTEPEC HAS BEEN
REPORTING NLY WINDS TO VERY NEAR 50 KT DURING THE COURSE OF THE
DAY. MODEL GUIDANCE FROM 30 METER GFS AND NAM GUIDANCE INDICATES
THAT THE STORM FORCE CURRENTLY BEING EXPERIENCED THROUGH THE
GULF AS WELL AS DOWNSTREAM FROM THE GULF WILL SLOWLY DECREASE TO
GALE FORCE TONIGHT INTO EARLY SAT MORNING...AND CONTINUE THROUGH
SUN MORNING FOLLOWED BY VERY STRONG TO NEAR-GALE CONDITIONS
THROUGH TUE WITH PEAK WINDS REACHING MINIMAL GALE AROUND SUNRISE
DUE TO DIURNAL EFFECTS. NO SIGNIFICANT CHANGE IS EXPECTED IN THE
SYNOPTIC PATTERN...WITH NORTHERLY WINDS IN THE GULF OF MEXICO
AND PERSISTENT STRONG PRES GRADIENT IN CENTRAL AMERICA.

THE GULF OF PAPAGAYO WILL ALSO HAVE STRONG PERSISTENT NE WINDS
THROUGH MON IN THIS SYNOPTIC PATTERN. FRESH TO STRONG E-NE WINDS
WILL EXTEND FAR DOWNWIND FROM THE SOURCE REGIONS NEAR TEHUANTEPEC
AND GULF OF PAPAGAYO...RESULTING IN VERY LARGE AREA OF ELEVATED
SEA HEIGHTS IN NE SWELL THROUGH SAT NIGHT EXTENDING ROUGHLY FROM
05N TO 14N BETWEEN 92W AND 113W. N TO NE WINDS OF 20-25 KT
SURGING THROUGH THE GULF OF PANAMA ARE EXPECTED TO CONTINUE WITH
LITTLE CHANGE INTO EARLY NEXT WEEK.

[cycloneye]

Good morning.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
452 AM AST SAT JAN 19 2013

.SYNOPSIS...MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL CONTINUE TO WEAKEN AS POLAR TROUGH
AMPLIFIES ACROSS NORTH AMERICA/WESTERN ATLANTIC.

&&

.DISCUSSION...MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL REMAIN AS THE DOMINANT WEATHER
FEATURE ACROSS THE FORECAST AREA FOR THE NEXT SEVERAL DAYS. AS
A RESULT...A GENERALLY FAIR AND MAINLY STABLE WEATHER PATTERN IS
EXPECTED. HOWEVER...LOW LEVEL MOISTURE CONFINED BELOW 800/750 HPA
WILL CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME AND
WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN INTERVALS OF CLOUDINESS
AND A FEW SHOWERS EACH DAY. AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
452 AM AST SAT JAN 19 2013

.SYNOPSIS...MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL CONTINUE TO WEAKEN AS POLAR TROUGH
AMPLIFIES ACROSS NORTH AMERICA/WESTERN ATLANTIC.

&&

.DISCUSSION...MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL REMAIN AS THE DOMINANT WEATHER
FEATURE ACROSS THE FORECAST AREA FOR THE NEXT SEVERAL DAYS. AS
A RESULT...A GENERALLY FAIR AND MAINLY STABLE WEATHER PATTERN IS
EXPECTED. HOWEVER...LOW LEVEL MOISTURE CONFINED BELOW 800/750 HPA
WILL CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME AND
WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN INTERVALS OF CLOUDINESS
AND A FEW SHOWERS EACH DAY. AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
452 AM AST SAT JAN 19 2013

.SYNOPSIS...MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL CONTINUE TO WEAKEN AS POLAR TROUGH
AMPLIFIES ACROSS NORTH AMERICA/WESTERN ATLANTIC.

&&

.DISCUSSION...MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN WILL REMAIN AS THE DOMINANT WEATHER
FEATURE ACROSS THE FORECAST AREA FOR THE NEXT SEVERAL DAYS. AS
A RESULT...A GENERALLY FAIR AND MAINLY STABLE WEATHER PATTERN IS
EXPECTED. HOWEVER...LOW LEVEL MOISTURE CONFINED BELOW 800/750 HPA
WILL CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME AND
WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN INTERVALS OF CLOUDINESS
AND A FEW SHOWERS EACH DAY. EARLY NEXT WORK WEEK...THE AFOREMENTIONED
POLAR TROUGH WILL SUSTAIN A SURFACE FRONT ACROSS THE WESTERN
ATLANTIC...WITH AN INVERTED TROUGH REACHING THE EASTERN CARIBBEAN.
UNDER INFLUENCE OF THIS INVERTED TROUGH WINDS WILL VEER TO THE
SOUTHEAST...RESULTING IN A WARMING TREND ACROSS THE LOCAL ISLANDS.

&&

.AVIATION...CLOUDS INCREASING FROM EAST TO WEST THROUGH THE DAY
WITH CIGS BCMG BKN-OVC040 WITH A FEW SHOWERS. ENE WINDS 12G16KT
BCMG LIGHT AND VARIABLE AT NIGHT. CLOUDS WILL STICK AROUND
THROUGH THE NIGHT WITH GREATER CVRG OF SHOWERS TONIGHT.

&&

.MARINE...WINDS UP TO 18 KNOTS AND SEAS 3 TO 5 FEET ARE EXPECTED
ACROSS THE LOCAL WATERS THROUGH AT LEAST SUNDAY. A SMALL NORTH
SWELL WILL START AFFECTING THE ATLANTIC COASTAL WATERS SUNDAY
NIGHT RAISING SEAS BRIEFLY TO 6 FT.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 81 73 83 73 / 20 40 40 20
STT 84 72 85 72 / 20 30 30 20

[cycloneye]

January 19 Jamaica forecast:

Code: Select all

Significant Feature: Cold front over the western Caribbean.

Morning: Mostly sunny.

Afternoon: Partly cloudy with isolated showers over sections of the island.

Tonight: Fair.

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

Temperatures: High: 31C (88F)     Low: 23C (73F)

 

Location
 Sunrise
 Sunset
 
Kingston
 6:42 a.m.
 5:55 p.m.
 
Montego Bay
 6:47 a.m.
 6:00 p.m.
 
Negril
 6:48 a.m.
 6:01 p.m.
 


[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
351 PM AST SAT JAN 19 2013

.SYNOPSIS...AN ELONGATED MID TO UPPER LEVEL RIDGE ACROSS THE
CENTRAL ATLANTIC INTO THE EASTERN CARIBBEAN WILL REMAIN THE MAIN
WEATHER FEATURE LOCALLY FOR THE NEXT SEVERAL DAYS BEFORE
WEAKENING LATE IN THE WEEK...AS A POLAR TROUGH AMPLIFIES ACROSS
NORTH AMERICA AND THE WESTERN ATLANTIC.

&&

.DISCUSSION...THE MID TO UPPER LEVEL RIDGE WILL REMAIN THE MAIN
WEATHER FEATURE LOCALLY FOR THE NEXT SEVERAL DAYS...PRODUCING A
GENERALLY FAIR AND MAINLY DRY WEATHER PATTERN ACROSS THE LOCAL
AREA. HOWEVER...LOW LEVEL MOISTURE CONFINED BELOW 800/750 HPA
WILL CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME AND
WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN INTERVALS OF
CLOUDINESS AND A FEW SHOWERS EACH DAY. DURING THE EARLY TO MID
PART OF NEXT WEEK...THE AFOREMENTIONED POLAR TROUGH WILL SUSTAIN
A SURFACE FRONT ACROSS THE WESTERN ATLANTIC...WITH AN INVERTED
TROUGH POSSIBLY REACHING THE EASTERN CARIBBEAN. UNDER INFLUENCE
OF THIS INVERTED TROUGH WINDS WILL VEER TO THE SOUTHEAST...
RESULTING IN A WARMING TREND ACROSS THE LOCAL ISLANDS.

&&

.AVIATION...VFR CONDITIONS EXPECTED FOR THE NEXT 24 HOURS. CIGS
WILL BE MAINLY BETWEEN FL050-070 UNTIL ABOUT 19/23Z. WINDS WILL
BE FROM THE EAST TO EAST NORTHEAST AT 10-15 KNOTS WITH A FEW
HIGHER GUSTS...DECREASING OVERNIGHT. PASSING ISOLATED SHOWERS MAY
CAUSE SOME VCSH ACROSS THE USVI/BVI...TJSJ...AND TJBQ.

&&

.MARINE...EXPECT WINDS OF 17 KNOTS OR LESS AND SEAS OF 6 FEET OR
LESS ACROSS THE REGIONAL WATERS THROUGH AT LEAST MONDAY.

&&

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

[cycloneye]

Good morning.


AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
525 AM AST SUN JAN 20 2013

.SYNOPSIS...AN ELONGATED MID TO UPPER LEVEL RIDGE ACROSS THE
CENTRAL ATLANTIC INTO THE EASTERN CARIBBEAN WILL CONTINUE TO
SLOWLY WEAKEN OVER THE NEXT FEW DAYS...AS POLAR TROUGH AMPLIFIES
ACROSS NORTH AMERICA AND THE WESTERN ATLANTIC.

&&

.DISCUSSION...A GENERALLY FAIR AND MAINLY DRY WEATHER PATTERN
WILL CONTINUE TO PREVAIL OVER THE NEXT SEVERAL DAYS AS AN
ELONGATED MID TO UPPER LEVEL RIDGE ACROSS THE CENTRAL ATLANTIC
INTO THE EASTERN CARIBBEAN REMAINS THE MAIN WEATHER FEATURE.
HOWEVER...LOW LEVEL MOISTURE CONFINED BETWEEN 800/750 HPA WILL
CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME...AND
WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN INTERVALS OF
CLOUDINESS AND A FEW SHOWERS EACH DAY. THE AFOREMENTIONED POLAR
TROUGH WILL SUSTAIN A SURFACE FRONT ACROSS THE WESTERN ATLANTIC
EARLY THIS WEEK...WITH AN INVERTED TROUGH REACHING THE EASTERN
CARIBBEAN BY MID WEEK. UNDER INFLUENCE OF THIS INVERTED TROUGH
THE WINDS WILL VEER TO THE SOUTHEAST ON TUESDAY...RESULTING IN
A WARMING TREND ACROSS THE LOCAL ISLANDS.

&&

.AVIATION...CIGS BKN040 WRN PR WITH A FEW LIGHT SHOWERS POSSIBLE.
TJSJ...USVI AND LEEWARD ISLANDS TERMINALS WILL ONLY HAVE A FEW
CLOUDS. ENE WINDS 12G16KT BCMG LIGHT AND VARIABLE AT NIGHT.


&&

.MARINE...WINDS OF 17 KNOTS OR LESS AND SEAS OF UP TO 6 FEET IN
NORTH SWELLS ARE EXPECTED ACROSS THE REGIONAL WATERS THROUGH AT
LEAST MONDAY.

&&

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

[cycloneye]

January 20 Jamaica forecast:

Code: Select all

Significant Feature: Cold front over the western Caribbean.

Morning: Mostly sunny.

Afternoon: Partly cloudy with isolated showers over sections of the island.

Tonight: Fair.

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

Temperatures: High: 31C (88F)     Low: 23C (73F)

 

Location
 Sunrise
 Sunset
 
Kingston
 6:42 a.m.
 5:55 p.m.
 
Montego Bay
 6:47 a.m.
 6:00 p.m.
 
Negril
 6:48 a.m.
 6:01 p.m.
 


[Macrocane]

The cold and windy weather will stay here this week although less intense than in the past few days:

EPAC TWD

ELSEWHERE AT THE LOW LEVELS...
CONTINUED NORTHEASTERLY WINDS IN SW GULF OF MEXICO ARE MOVING
ACROSS CHIVELA PASS AND BRINGING GALE FORCE N-NE WINDS INTO GULF
OF TEHUANTEPEC. WINDS ARE EXPECTED TO DIMINISH THROUGH
TEHUANTEPEC NEXT 24 HOURS...TO MINIMAL GALES...AND PERSIST
THROUGH MON NIGHT. NEXT BLAST OF COLD AIR IN GULF OF MEXICO
INCREASES WINDS AGAIN LATE IN FORECAST PERIOD.

CURRENT GALE FORCE WINDS OVER SW CARIBBEAN REINFORCE FRESH TO
STRONG NE WINDS ALONG GULFS OF PAPAGAYO AND FONSECA THROUGH
FORECAST PERIOD WITH STRONGEST WINDS NOTED IN EARLY MORNINGS AS
DOWNSLOPE DRAINAGE WINDS ADD STRENGTH TO WIND FIELD. STRONG NE
WINDS ACROSS SW CARIBBEAN ALSO CONTRIBUTES TO FRESH N BREEZE
OVER GULF OF PANAMA THROUGH LATE MON.

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
330 PM AST SUN JAN 20 2013

.SYNOPSIS...AN ELONGATED MID TO UPPER LEVEL RIDGE ACROSS THE
CENTRAL ATLANTIC INTO THE EASTERN CARIBBEAN WILL REMAIN THE MAIN
WEATHER FEATURE LOCALLY FOR THE NEXT SEVERAL DAYS BEFORE WEAKENING
LATE IN THE WEEK...AS A POLAR TROUGH AMPLIFIES ACROSS NORTH
AMERICA AND THE WESTERN ATLANTIC.

&&

.DISCUSSION...THE MID TO UPPER LEVEL RIDGE WILL REMAIN THE MAIN
WEATHER FEATURE LOCALLY FOR THE NEXT SEVERAL DAYS...PRODUCING A
GENERALLY FAIR AND MAINLY DRY WEATHER PATTERN ACROSS THE LOCAL
AREA. HOWEVER...LOW LEVEL MOISTURE CONFINED BELOW 800/750 HPA
WILL CONTINUE TO MOVE ACROSS THE LOCAL AREA FROM TIME TO TIME AND
WILL COMBINE WITH LOCAL EFFECTS TO RESULT IN INTERVALS OF
CLOUDINESS AND A FEW SHOWERS EACH DAY. DURING THE WEEK...THE
AFOREMENTIONED POLAR TROUGH WILL SUSTAIN A SURFACE FRONT MOVING
EAST SOUTHEAST ACROSS THE WESTERN ATLANTIC...WITH AN INVERTED
TROUGH POSSIBLY REACHING THE EASTERN CARIBBEAN. UNDER INFLUENCE OF
THIS INVERTED TROUGH...WINDS WILL GRADUALLY VEER TO THE
SOUTHEAST...RESULTING IN A WARMING TREND ACROSS THE LOCAL
ISLANDS.

ON A PERSONAL NOTE...TODAY MARKS MY LAST OPERATIONAL SHIFT HERE
AT WFO SAN JUAN AFTER 18+ YEARS...AS WE RETURN TO NEW ENGLAND.
THROUGH THE YEARS...IT HAS BEEN BOTH A PLEASURE AND HONOR FOR ME
TO WORK WITH SOME OF THE FINEST...MOST TALENTED AND DEDICATED
EMPLOYEES IN THE NATIONAL WEATHER SERVICE AND TO SERVE THE
RESIDENTS AND VISITORS OF PUERTO RICO AND THE U.S. VIRGIN ISLANDS.
THANK YOU./BCS

&&

.AVIATION...EXPECT PREVAILING VFR CONDITIONS TO CONTINUE ACROSS
THE LOCAL ISLANDS AND AT ALL TAF SITES DURING THE NEXT 24 HOURS.
HOWEVER...BRIEF MVFR CONDITIONS AND LOCAL MOUNTAIN OBSCURATIONS
ARE POSSIBLE IN ISOLATED PASSING SHOWERS.

&&

.MARINE...EXPECT WINDS OF 17 KNOTS OR LESS AND SEAS OF 6 FEET OR
LESS ACROSS THE REGIONAL WATERS THROUGH AT LEAST TUESDAY. SMALL
BOAT OPERATORS SHOULD EXERCISE CAUTION ACROSS PARTS OF THE LOCAL
WATERS.

&&

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

[cycloneye]

Good morning.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
435 AM AST MON JAN 21 2013

.SYNOPSIS...A GENERALLY FAIR WEATHER PATTERN WILL CONTINUE TO
PREVAIL ACROSS THE LOCAL AREA...AS AN ELONGATED MID TO UPPER
LEVEL RIDGE PERSISTS ACROSS THE TROPICAL ATLANTIC INTO THE
CARIBBEAN.

&&

.DISCUSSION...AN ELONGATED MID TO UPPER LEVEL RIDGE WILL REMAIN
THE MAIN WEATHER FEATURE LOCALLY...WITH ASSOCIATED SUBSIDENCE CAP
WEAKENING DURING THE NEXT FEW DAYS. POLAR TROUGH ACROSS NORTH
AMERICA AND THE WESTERN ATLANTIC WILL CONTINUE TO SUSTAIN A
SURFACE FRONT/SHEAR LINE WHICH IS FORECAST TO MOVE SOUTHEAST WHILE
DISSIPATES NORTH OF THE AREA.

AS A RESULT...OVER THE NEXT FEW DAYS...A GENERALLY FAIR AND MAINLY
STABLE WEATHER PATTERN WILL CONTINUE TO PREVAIL WITH CLOUDINESS
AND PASSING SHOWERS FROM TIME TO TIME..BUT ESPECIALLY MONDAY NIGHT
AND TUESDAY. WINDS WILL VEER TO THE SOUTHEAST ON TUESDAY...AS
SURFACE FRONT/SHEAR LINE MOVES SOUTHEAST. THIS WILL RESULT IN A
WARMING TREND ACROSS THE LOCAL ISLANDS. A WETTER PATTERN COULD BE
EXPECTED DURING THE UPCOMING WEEKEND INTO EARLY NEXT WEEK WHEN A
SURFACE FRONT/SHEAR LINE IS FORECAST TO REACH THE LOCAL AREA.

&&

.AVIATION...VFR CONDS WILL CONTINUE ACROSS THE LCL ISLANDS AND AT
ALL TAF SITES DURG THE NXT 24 HOURS. HOWEVER AT LEAST TIL 21/14Z...
PASSING LIGHT TRADE WINDS SHWRS W/SCT-BKN CLD LAYERS BTW FL020-FL080
WILL REMAIN PSBL OVR THE COASTAL WATERS...AND EN ROUTE TO USVI AND
THE NRN LEEWARD ISLANDS. BRIEF MTN TOP OBSCR ALSO PSBL ACROSS ERN
INTERIOR SECTIONS OF PR WITH PASSING LOW CLDS AND -SHRA. WINDS WILL
CONTINUE FROM THE EAST BTW 10 TO 15 KNOTS BLO FL150 THEN BCM
WESTERLY AND INCR W/HT ABV FL250.

&&

.MARINE...A MODERATE NORTH NORTHWEST SWELL COMBINED WITH EASTERLY
WIND WAVES WILL CREATE HAZARDOUS MARINE CONDITIONS THROUGH THIS
AFTERNOON ACROSS THE OUTER ATLANTIC WATERS.

&&

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

[cycloneye]

January 21 Jamaica forecast:

Code: Select all

Significant Feature: Surface trough over the western Caribbean.

Morning: Mostly sunny.

Afternoon: Partly cloudy with isolated showers over sections of the island.

Tonight: Fair.

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

Temperatures: High: 31C (88F)     Low: 23C (73F)

 

Location
 Sunrise
 Sunset
 
Kingston
 6:42 a.m.
 5:56 p.m.
 
Montego Bay
 6:47 a.m.
 6:01 p.m.
 
Negril
 6:48 a.m.
 6:02 p.m.
 


[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
245 PM AST MON JAN 21 2013

.DISCUSSION...RELATIVELY DRY EASTERLY FLOW TO CONTINUE ALL WEEK.
BEST CHANCES FOR SHOWERS TO BE TOMORROW (TUE) THEN FROM SAT AND
INTO EARLY NEXT WEEK. MOIST PLUME NEARING 60W IS MOVING WEST
ABOUT 17 KT. EXTRAPOLATION FROM SATELLITE VALIDATES GFS IN ITS
FUTURE PROGRESSION THOUGH MAYBE A SHADE TOO LOW IN PRECIPITABLE
WATER VALUES.

POPS WERE RAISED SLIGHTLY ACROSS NORTH SIDE OF PR FOR TUE AFTERNOON
AS THE MOISTURE LOOKS A LITTLE BETTER THAN TODAY. SUBSIDENCE INVERSION
WILL BE WEAKER THOUGH STILL TOO STRONG FOR DEEP CONVECTION. STILL...
THIS FLOW IS TOO DRY TO CONSIDER MUCH PRECIPITATION UNTIL POSSIBLY
THE WEEKEND AND ONLY NUDGED THE INTERIOR POPS UP FOR THEN.

MARINE...SWELLS STILL ARE VERY SLOWLY SUBSIDING AND WILL EXPIRE
SMALL CRAFT ADVISORY AS INDICATED. CONDITIONS TO REMAIN RELATIVELY
QUIET NEXT FEW DAYS.

&&

.AVIATION...VFR CONDS WILL CONTINUE ACROSS THE LOCAL TAF SITES FOR
THE NEXT 24 HOURS. HOWEVER...PASSING LIGHT TRADE WINDS SHRA W/
SCT-BKN CLOUD LAYERS BTW FL020-FL080 WILL REMAIN PSBL OVR THE
COASTAL WATERS. BRIEF MTN TOP OBSCR ALSO PSBL OVER THE MOUNTAINS
SECTIONS OF PR WITH PASSING LOW CLDS AND -SHRA THIS AFTERNOON. SFC
WINDS WILL CONTINUE FROM THE EAST BTW 10 TO 15 KNOTS...DECREASING
THIS EVENING AND OVERNIGHT.

&&

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

[cycloneye]

Good morning.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
553 AM AST TUE JAN 22 2013

.SYNOPSIS...A RELATIVELY DRY WEATHER PATTERN...TYPICAL FOR THIS TIME
OF THE YEAR...IS EXPECTED TO CONTINUE ACROSS THE LOCAL ISLANDS FOR
THE NEXT SEVERAL DAYS...AS AN ELONGATED MID TO UPPER LEVEL RIDGE
PERSISTS ACROSS THE TROPICAL ATLANTIC INTO THE NORTHEAST CARIBBEAN.

&&

.DISCUSSION...ISOLATED TO LOCALLY SCATTERED PASSING SHOWERS AFFECTED
THE EASTERN SECTIONS OF PUERTO RICO AS WELL AS VIEQUES...CULEBRA AND
THE U.S.V.I. DURING THE OVERNIGHT HOURS. LATEST SATELLITE IMAGES THIS
MORNING DEPICTED FEW WESTWARD-MOVING BANDS OF MOISTURE ACROSS THE
ATLANTIC WATERS EAST OF THE FA. ONE HAS ALREADY MOVED ACROSS PUERTO
RICO OVERNIGHT AND THE OTHER ONE IS JUST ACROSS THE NORTHERN LEEWARD
ISLANDS EARLY IN THE MORNING. THESE BANDS OF MOISTURE ARE
EXPECTED TO PRODUCE SHOWERS ACROSS THE USVI...CULEBRA...VIEQUES AND
EASTERN SECTIONS OF PUERTO RICO THIS MORNING. SUBSIDENCE INVERSION
WILL BE WEAKER TODAY..BUT STILL TOO STRONG FOR DEEP CONVECTION TO
DEVELOP. AFTER THE PASSAGE OF THESE BANDS OF MOISTURE...THE MID TO
UPPER LEVEL RIDGE WILL MAINTAIN A GENERALLY DRY AND STABLE
WEATHER PATTERN FOR THE REST OF THE WORK WEAK...WITH ONLY FEW PATCHES
OF LOW TO MID LEVEL CLOUDS AND ISOLATED QUICK PASSING SHOWERS
EMBEDDED IN THE EASTERLY TRADES AFFECTING PORTIONS OF THE LOCAL ISLANDS.

&&

.AVIATION...OVERALL VFR CONDS EXPECTED ACROSS THE LCL TAF SITES FOR
THE NXT 24 HOURS. A N-S ORIENTED LINE OF CLDS WITH FEW EMBEDDED
SHWRS NOW CROSSING TKPK AND TNCM...WILL CONT EWD AND MAY PRODUCE
BRIEF MVFR IN LOW CIGS AND PASSING SHRA EN ROUTE BTW ERN PR AND NRN
LEEWARDS AT LEAST TIL 22/14Z. ALSO...BRIEF MTN TOP OBSCR WILL REMAIN
PSBL OVR ERN PR DURG THE EARLY MORNING HRS. SFC WND WILL BECOME MORE
SE TODAY AT 10 TO 15 KNOTS...WITH SOME HIGHER GUST NEAR THE PASSING
SHRA. L/LVL WNDS BLO FL150 CONTINUE FM ESE AT 10-15 KTS THEN BACKING
AND BCMG FM W WHILE INCR W/HT ABV FL250.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 72 83 71 / 40 30 20 10
STT 85 75 86 75 / 30 30 20 20