Caribbean - Central America Weather

[cycloneye]

From the 11 AM EDT discussion.

GIVEN THE TRACK AND INTENSITY FORECAST...ALONG WITH THE WEAK WIND
FIELD OVER THE SOUTHERN SEMICIRCLE OF THE CYCLONE...WATCHES OR
WARNINGS ARE NOT NEEDED FOR THE ISLANDS OF THE NORTHEAST CARIBBEAN.

[Gustywind]

From the 11 AM EDT discussion.

GIVEN THE TRACK AND INTENSITY FORECAST...ALONG WITH THE WEAK WIND
FIELD OVER THE SOUTHERN SEMICIRCLE OF THE CYCLONE...WATCHES OR
WARNINGS ARE NOT NEEDED FOR THE ISLANDS OF THE NORTHEAST CARIBBEAN.

Maybe too early to make quick conclusions, but Dorian effects should be very minimal if things stays like that

[cycloneye]

It looks like little rain will come from the remnants of Dorian to the NE Caribbean.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
249 PM AST SAT JUL 27 2013

.SYNOPSIS...TUTT ACROSS THE SOUTHWEST ATLANTIC INTO THE EAST CENTRAL
CARIBBEAN WILL WEAKEN OVER THE WEEKEND...AS HIGH MOVES IN FROM THE
TROPICAL ATLANTIC INTO THE EASTERN CARIBBEAN. A SECOND TUTT IS
EXPECTED TO DEVELOP ACROSS THE CENTRAL ATLANTIC EARLY NEXT WORK
WEEK. SURFACE HIGH ACROSS THE NORTH CENTRAL ATLANTIC WILL CONTINUE
TO PROMOTE A MODERATE TO FRESH TRADE WIND FLOW ACROSS THE LOCAL
ISLANDS. TROPICAL STORM DORIAN IS FORECAST TO PASS NORTH OF THE
LOCAL ISLANDS LATE SUNDAY NIGHT THROUGH MONDAY AS A TROPICAL
DEPRESSION.

&&

.DISCUSSION...SKIES WERE PARTLY TO MOSTLY CLOUDY OVER THE LOCAL
ISLANDS DURING THE DAY TODAY. SHOWERS WITH THUNDERSTORMS DEVELOPED
OVER NORTHWEST PUERTO RICO THIS AFTERNOON. WINDS WERE FROM THE
EAST TO EAST SOUTHEAST AT 5 TO 15 MPH WITH SOME HIGHER GUSTS AND
SEA BREEZE VARIATIONS. TEMPERATURES WERE IN THE UPPER 80S IN
COASTAL AREAS.

BASED ON THE LATEST FORECAST FROM THE NATIONAL HURRICANE CENTER...
TROPICAL STORM DORIAN IS EXPECTED TO PASS NORTH OF THE LOCAL ISLANDS
LATE SUNDAY NIGHT THROUGH MONDAY AS A TROPICAL DEPRESSION. MODEL
GUIDANCE CONTINUED TO INDICATE THAT MOST OF ITS ASSOCIATED MOISTURE
SHOULD REMAIN NORTH OF THE REGION.

SHOWER COVERAGE AND THUNDERSTORM INTENSITY SHOULD DECREASE SUNDAY
INTO EARLY NEXT WORK WEEK AS TUTT MOVES WEST WHILE WEAKENING...
AND HIGH ALOFT ESTABLISHES OVER THE EASTERN CARIBBEAN. IN ADDITION...
AS THIS PATTERN EVOLVES..A DRIER AIR MASS WILL MOVE IN FROM THE
EAST. WRF AND GFS SUGGESTED PWAT VALUES BELOW 2 INCHES OVER THE
NEXT FEW DAYS. UNDER THE PREVAILING WIND FLOW...THIS WILL RESULT
IN PASSING SHOWERS ACROSS EASTERN PUERTO RICO AND U.S. VIRGIN
ISLANDS DURING THE MORNING HOURS...FOLLOWED BY AFTERNOON CONVECTION...
DRIVEN BY LOCAL EFFECT AND DIURNAL HEATING...ACROSS WESTERN PUERTO
RICO EACH DAY. AT THIS TIME...A MOISTURE SURGE IS EXPECTED TO
APPROACH THE LOCAL ISLANDS TUESDAY EVENING...AND MAY INCREASE
OVERNIGHT SHOWER ACTIVITY ACROSS THE LOCAL ISLANDS.

&&

.AVIATION...XPT VFR THRU SUNDAY XCP IN ISOLD MVFR IN SHRA/TSRA BOTH
AFT WI OBSCD MTNS. WINDS BLO FL150 ESE 15-20 KT BCMG E TONITE THEN
WEAKENING SUNDAY.

&&

.MARINE...LATEST GUIDANCE CONTINUED TO INDICATE SEAS UP TO 7 FEET
ACROSS THE OFFSHORE WATERS ON MONDAY...AS REMNANTS OF TS DORIAN
MOVE NORTH OF THE AREA. SURFACE HIGH ACROSS THE NORTH CENTRAL
ATLANTIC WILL CONTINUE TO PROMOTE A MODERATE TO FRESH TRADE WIND
FLOW ACROSS THE LOCAL ISLANDS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 78 87 77 89 / 20 30 20 20
STT 78 89 78 88 / 20 20 30 30

[cycloneye]

The last advisory on Dorian.

BULLETIN
REMNANTS OF DORIAN ADVISORY NUMBER 15
NWS NATIONAL HURRICANE CENTER MIAMI FL AL042013
500 PM AST SAT JUL 27 2013

...DORIAN DEGENERATES INTO A TROPICAL WAVE...
...THIS IS THE LAST ADVISORY...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...18.9N 54.7W
ABOUT 550 MI...890 KM E OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 24 MPH...39 KM/H
MINIMUM CENTRAL PRESSURE...1011 MB...29.85 INCHES

[cycloneye]

Good morning. The remnants of Dorian will pass just north of the islands today thru Monday and may bring some showers.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
436 AM AST SUN JUL 28 2013

.SYNOPSIS...SURFACE HIGH PRESSURE OVER THE WEST CENTRAL ATLANTIC
HELPING TO MAINTAIN MODERATE EASTERLY TRADES ACROSS THE REGION...AS
A STRONG TROPICAL WAVE PREVIOUSLY TROPICAL STORM DORIAN CONTINUED
TO MOVE WESTWARD AND JUST NORTHEAST OF THE NORTHERN LEEWARD ISLANDS.
CONSIDERABLE CLOUDINESS AND CONVECTIVE CLUSTERS OF SHOWERS AND STRONG
THUNDERSTORMS ASSOCIATED WITH THE REMNANTS OF DORIAN WERE QUICKLY MOVING
WESTWARD. THIS ACTIVITY IS STILL IS EXPECTED TO PASS JUST NORTH OF THE
LOCAL ISLANDS LATE TONIGHT AND MONDAY. RETROGRESSING TUTT LOW ACROSS
THE SOUTHWEST ATLANTIC DIPPING SOUTH ACROSS HISPANIOLA AND THE MONA
PASSAGE...AND AN UPPER HIGH APPROACHING FROM THE EAST WAS HELPING
TO CREATE A SOUTHERLY UPPER LEVEL WIND FLOW ACROSS THE REGION.

&&

.DISCUSSION...THE PREVAILING EASTERLIES WILL CONTINUE TO BRING
FRAGMENTS OF LOW TO MID LEVEL MOISTURE FROM THE APPROACHING TROPICAL
WAVE ACROSS THE REGION. THE PROXIMITY OF THE UPPER TROUGH WILL HELP
ENHANCE LOCAL CONVECTION THROUGH THE MORNING HOURS MAINLY ACROSS THE
LOCAL WATERS. SOME SHOWERS WILL BRUSH PARTS OF THE NORTH AND EAST
COASTAL SECTIONS OF THE ISLANDS THROUGH THE EARLY MORNING HOURS.

FOR THE REST OF THE DAY AND EVENING HOURS...EXPECT VARIABLY
CLOUDY SKIES WITH INCREASING CLOUDINESS AS THE MOISTURE REMNANTS
AND CONVECTIVE DEBRIS FROM DORIAN MAY BRIEFLY AFFECT THE AREA AS
IT PASSES TO OUR NORTH. THIS AVAILABLE MOISTURE ALONG WITH DIURNAL
AND LOCAL EFFECTS WILL INDUCE SOME AFTERNOON CONVECTION MAINLY
OVER THE CORDILLERA CENTRAL AND WESTERN INTERIOR SECTIONS OF
PUERTO RICO.

GFS MODEL GUIDANCE STILL DEPICT DECREASING PWAT VALUES OVER THE
NEXT COUPLE OF DAYS WITH VALUES DOWN TO NEAR AN INCH OR SO ON
MONDAY. THEREFORE LOOKING FOR EVEN DRIER CONDITIONS DURING THE
BEGINNING OF THE WORK WEEK. HOWEVER STILL WILL NOT RULE OUT THE
CHANCE FOR ISOLATED TO SCATTERED DIURNALLY INDUCED SHOWERS AND
THUNDERSTORMS EACH DAY.

&&

.AVIATION...MOSTLY VFR CONDITIONS WILL CONTINUE ACROSS THE LOCAL
FLYING AREA UNTIL 28/16Z. AFTER 28/16Z EXPECT THE DEVELOPMENT OF
SHRA/TSRA ACROSS WESTERN PR AND NORTHWEST OF EL YUNQUE PRODUCING
MOUNTAIN OBSCURATIONS WITH PERIODS OF MVFR OR EVEN IFR CONDITIONS
MAINLY ACROSS TJMZ AND TJBQ. LOW LEVEL WINDS WILL CONTINUE FROM THE
EAST SOUTHEAST AT 5 TO 15 KT.

&&

.MARINE...THE STRONG TROPICAL WAVE MOVING WEST ACROSS THE ATLANTIC
AND JUST NORTH OF THE REGION...MAY BRIEFLY GENERATE LOCALLY ROUGH
AND HAZARDOUS SEAS OFFSHORE LATE TONIGHT THROUGH MONDAY. FOR THIS
REASON SMALL CRAFT OPERATORS SHOULD EXERCISE CAUTION ACROSS PARTS
OF THE COASTAL WATERS LATER TONIGHT. A SMALL CRAFT ADVISORY WILL
BE IN EFFECT FOR THE OFFSHORE ATLANTIC ON MONDAY DUE TO HAZARDOUS
SEAS POSSIBLE UP TO 7 FEET.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 77 89 78 / 30 20 20 20
STT 88 78 90 80 / 20 30 30 30

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
235 PM AST SUN JUL 28 2013

.SYNOPSIS...TUTT NORTHWEST OF THE LOCAL ISLANDS WILL CONTINUE TO
RETROGRESS WHILE WEAKENING. UPPER LEVEL HIGH ACROSS THE TROPICAL
ATLANTIC IS EXPECTED TO EXTEND ACROSS THE EASTERN CARIBBEAN OVER
THE NEXT FEW DAYS. A SECOND TUTT WILL DEVELOP ACROSS THE CENTRAL
ATLANTIC EARLY NEXT WORK WEEK. A TROUGH OF LOW PRESSURE...ASSOCIATED
WITH THE REMNANTS OF DORIAN...WILL MOVE NORTH OF PUERTO RICO AND
US VIRGIN ISLAND TONIGHT AND MONDAY.

&&

.DISCUSSION...SKIES WERE PARTLY CLOUDY OVER THE LOCAL ISLANDS DURING
THE DAY TODAY. SHOWERS WITH THUNDERSTORMS WERE NOTED ACROSS PORTIONS
OF EASTERN PUERTO RICO/USVI EARLY THIS MORNING...SPREADING ACROSS
WESTERN PUERTO RICO IN THE AFTERNOON. THESE SHOWERS AND THUNDERSTORMS
WERE THE RESULT OF LOW LEVEL MOISTURE COMBINED WITH THE PROXIMITY OF
A TUTT LOW NORTHWEST OF THE LOCAL AREA. WINDS WERE FROM THE EAST TO
EAST NORTHEAST AT 5 TO 15 MPH WITH SOME HIGHER GUSTS AND SEA BREEZE
VARIATIONS. TEMPERATURES WERE IN THE UPPER 80S IN COASTAL AREAS.

PASSING SHOWERS WITH ISOLATED THUNDERSTORMS ARE EXPECTED ACROSS THE
FORECAST AREA AS REMNANTS OF DORIAN MOVE NORTH OF THE LOCAL ISLANDS
TONIGHT INTO MONDAY MORNING. MODEL GUIDANCE SUGGESTED THAT MOST OF
SHOWER AND THUNDERSTORM ACTIVITY SHOULD REMAIN OVER THE ATLANTIC
WATERS...WITH SOME OF THESE SHOWERS AFFECTING PORTIONS OF THE
NORTHERN SLOPES OF PUERTO RICO AND SAINT THOMAS FROM TIME TO TIME.

SHOWER COVERAGE AND THUNDERSTORM INTENSITY IS EXPECTED TO DECREASE
EARLY NEXT WORK WEEK AS TUTT MOVES AWAY FROM THE LOCAL AREA...AND
UPPER HIGH EXTENDS OVER THE EASTERN CARIBBEAN. AS THIS PATTERN
EVOLVES...A DRIER AIR MASS WILL MOVE IN FROM THE EAST. AFOREMENTIONED
FACTORS WILL RESULT IN A TYPICAL SUMMER PATTERN TUESDAY THROUGH AT
LEAST THE END OF THE UPCOMING WORK WEEK...WITH A COUPLE OF MORNING
SHOWERS EMBEDDED IN THE TRADES ACROSS EASTERN PUERTO RICO/USVI...
FOLLOWED BY DIURNAL CONVECTION ACROSS PORTIONS OF WESTERN PUERTO
RICO EACH DAY.

&&

.AVIATION...MOSTLY VFR THRU TONITE BUT SHRA/TSRA TO CAUSE AREAS
MVFR/ISOLD IFR IN AFT AND AREAS OF OBSCD MTNS. IFR/MVFR STILL
MORE LIKELY IN AFT AT TJMZ/TJBQ. TEMPO PDS IN TAFS THERE LOOK
APPROPRIATE. WIND BLO FL150 E 10-20 KT TODAY WEAKENING TO 5-15 KT
TONITE AND BCMB SE ON MON.

&&

.MARINE...A TROUGH OF LOW PRESSURE...ASSOCIATED WITH THE REMNANTS
OF DORIAN...WILL MOVE NORTH OF PUERTO RICO AND US VIRGIN ISLANDS
TONIGHT AND MONDAY. THIS MAY BRIEFLY GENERATE LOCALLY ROUGH AND
HAZARDOUS SEAS OF UP TO 7 FEET ACROSS THE OFFSHORE ATLANTIC WATERS
LATE TONIGHT THROUGH MONDAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 77 87 78 88 / 20 20 20 20
STT 78 90 80 89 / 30 30 30 40

[cycloneye]

Good morning. No big effects wil be felt in PR today as the remnants of Dorian move north of the area.It looks like good weather will prevail for the rest of this week.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
537 AM AST MON JUL 29 2013

.SYNOPSIS...TUTT LOW NORTHWEST OF THE LOCAL ISLANDS WILL CONTINUE TO
SLOWLY RETROGRESS DURING THE NEXT SEVERAL DAYS. UPPER LEVEL HIGH
ACROSS THE TROPICAL ATLANTIC IS EXPECTED TO EXTEND ACROSS THE
NORTHEAST CARIBBEAN DURING THE NEXT FEW DAYS. A SECOND AND STRONGER
TUTT LOW WILL DEVELOP ACROSS THE CENTRAL ATLANTIC EARLY BY THE
MIDDLE OF THE WEEK. A TROPICAL WAVE...REMNANTS OF TROPICAL STORM
DORIAN...WILL MOVE NORTH OF THE LOCAL ISLANDS TODAY AND TONIGHT.

&&

.DISCUSSION...DOPPLER WEATHER RADAR DETECTED ISOLATED TO SCATTERED
SHOWERS AND FEW CLUSTERS OF STRONG THUNDERSTORMS ACROSS THE ATLANTIC
WATERS OVERNIGHT AND EARLY THIS MORNING. THIS ACTIVITY WAS
ASSOCIATED WITH A TROPICAL WAVE...REMNANTS OF TROPICAL STORM
DORIAN...MOVING ACROSS THE ATLANTIC WATERS NORTH OF THE LOCAL
ISLANDS TODAY. HOWEVER...MINIMAL SHOWER ACTIVITY...IF ANY...WAS
OBSERVED OVER LAND AREAS SO FAR THIS MORNING. THE TROPICAL WAVE WILL
CONTINUE TO MOVE WESTWARD ACROSS THE ATLANTIC WATERS TODAY AND
TONIGHT WITH MINIMAL INFLUENCES ACROSS THE FA. LATEST MODEL GUIDANCE
SUGGESTS THAT THE BULK OF THE PCPN AND THUNDERSTORM ACTIVITY
ASSOCIATED WITH THE WAVE...WILL REMAIN NORTH OF THE LOCAL ISLANDS.
THUS...THE TYPICAL SUMMER TIME WEATHER PATTERN IS EXPECTED TO
CONTINUE ACROSS THE LOCAL ISLANDS FOR THE NEXT SEVERAL DAYS...WITH
NIGHTTIME ISOLATED TO SCATTERED PASSING SHOWERS ACROSS THE USVI AND
EASTERN PUERTO RICO AND DIURNAL INDUCED SHOWER AND THUNDERSTORM
ACTIVITY ACROSS WESTERN AND INTERIOR PUERTO RICO EACH AFTERNOON. NO
MAJOR CHANCES IN THIS WEATHER PATTERN ARE EXPECTED IN THE
FORESEEABLE FUTURE.

A TUTT LOW JUST NORTHWEST OF THE LOCAL ISLANDS THIS MORNING IS
EXPECTED TO RETROGRESS FOR THE NEXT SEVERAL DAYS...DECREASING THE
SEVERITY OF THE AFTERNOON THUNDERSTORMS ACROSS WESTERN AND INTERIOR
PUERTO RICO. A WEAK UPPER LEVEL HIGH WILL MOVE ACROSS THE NORTHEAST
CARIBBEAN BEHIND THE TUTT LOW UNTIL AT LEAST THE MIDDLE OF THE WEEK.
A SECOND AND STRONGER TUTT LOW WILL DEVELOP ACROSS THE TROPICAL
ATLANTIC...NORTHEAST OF THE REGION...BY THE MIDDLE OF THE
WEEK.

&&

.AVIATION...VFR CONDS EXPECTED OVERNIGHT ACROSS THE LOCAL TAF SITES.
FEW PASSING -SHRA VCTY COASTAL TAF SITES OF NRN PR AND NRN VI BUT
MAINLY OVR WATER AND EN ROUTE BTW ISLANDS. VFR CONDS DURG PD WITH
THE EXCEPTION OF TJBQ/TJMZ AFTER 29/16Z WHERE THERE IS A SLIGHT
CHANCE FOR DIURNAL INDUCED CONVECTION TIL AT LEAST 29/22Z. WINDS WILL
BE LIGHT AND VARIABLE OVERNIGHT...BECOMING SOUTHEASTERLY EXCEPT FOR
SEA BREEZE VARIATIONS AROUND 10-12 KTS AFTER 29/14Z.

&&

.MARINE...AT 5 AM AST...BUOY 41043 INDICATED A WAVE HEIGHT OF 9.5
FEET AT 11 SECONDS. BOTH WAVE HEIGHT AND PERIOD WERE RISING.
A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THE OFFSHORE
ATLANTIC WATERS UNTIL THIS AFTERNOON. SEAS SHOULD COME DOWN
RAPIDLY AFTER THE PASSAGE OF THE WAVE TONIGHT AND TUESDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 78 89 78 / 30 20 20 30
STT 89 78 90 80 / 30 30 40 40

[Gustywind]

Let's enjoy the last days of July before August.

[cycloneye]

It was really very warm in PR with record breaking high temperatures as the south winds were the cause.

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
251 PM AST MON JUL 29 2013

.SYNOPSIS...TUTT WEST OF THE LOCAL AREA WILL CONTINUE TO MEANDER
AS A SECOND TUTT DEVELOPS ACROSS THE CENTRAL ATLANTIC. AT MID
LEVELS...RIDGE PATTERN WILL CONTINUE TO DOMINATE THE FORECAST
AREA OVER THE NEXT FEW DAYS. A TROUGH OF LOW PRESSURE...REMNANTS
OF TROPICAL STORM DORIAN...WILL CONTINUE TO MOVE WESTWARD ACROSS
THE ATLANTIC...NORTH OF THE LOCAL ISLANDS TONIGHT.

&&

.DISCUSSION...SKIES WERE MOSTLY SUNNY OVER THE LOCAL ISLANDS DURING
THE DAY TODAY. BRIEF SHOWERS WERE NOTED ACROSS PORTIONS OF NW PUERTO
RICO THIS AFTERNOON. WINDS WERE FROM THE SOUTHEAST AT 12 MPH WITH
SOME HIGHER GUSTS AND SEA BREEZE VARIATIONS. TEMPERATURES WERE IN
THE LOW 90S IN COASTAL AREAS.

A TROUGH OF LOW PRESSURE...REMNANTS OF TROPICAL STORM DORIAN...WILL
CONTINUE TO MOVE WESTWARD ACROSS THE ATLANTIC...NORTH OF THE LOCAL
ISLANDS TONIGHT. AS THIS FEATURE MOVES WEST...THE LOCAL AREA WILL
REMAIN UNDER THE SUBSIDENCE/DRY AIR SIDE...RESULTING IN LIMITED
SHOWER ACTIVITY THIS EVENING AND EARLY TUESDAY MORNING.

SHOWER ACTIVITY IS EXPECTED TO INCREASE SOMEWHAT ACROSS THE LOCAL
ISLANDS TUESDAY MORNING INTO TUESDAY AFTERNOON...AS A MOIST TONGUE
TRAILING REMNANTS OF DORIAN MOVES OVER THE AREA. HOWEVER...WEDNESDAY
THROUGH AT LEAST THE END OF THE WORK WEEK...A GENERALLY FAIR WEATHER
PATTERN IS EXPECTED TO PREVAIL WITH A FEW PASSING SHOWERS EMBEDDED
IN THE TRADES ACROSS EASTERN PUERTO RICO/USVI DURING THE MORNING
HOURS...FOLLOWED BY AFTERNOON CONVECTION ACROSS WESTERN PUERTO
RICO.

&&

.AVIATION...VFR CONDS EXPECTED ACROSS ALL THE LOCAL TAF SITES THROUGH
THE FORECAST PERIOD. LLVL WINDS WILL BE MAINLY FM THE SSE TO SE AT
AROUND 10-15 KTS .

&&

.MARINE...SEAS UP TO 7 FEET ACROSS THE OFFSHORE WATERS TIL THIS
EVENING. SEAS CONDITIONS EXPECTED TO QUICKLY IMPROVE TONIGHT AS
REMNANTS OF DORIAN MOVE FURTHER AWAY.

&&

.CLIMATE...A RECORD HIGH TEMPERATURE OF 93 DEGREES WAS SET TODAY
AT SAN JUAN/P.R. THIS TIED PREVIOUS RECORD OF 93 SET BACK IN 1984.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 79 90 79 89 / 20 20 30 30
STT 78 90 80 88 / 30 40 40 40

[Macrocane]

Mid Summer Drought is going to stop this week as a wetter pattern will establish over Central America:

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
219 PM EDT MON JUL 29 2013

DISCUSSION FROM JULY 29/00UTC: AT 250 HPA...A HIGH OVER WESTERN
TEXAS IS TO ANCHOR A RIDGE ACROSS THE SOUTHWEST USA TO THE
NORTHERN STATES OF MEXICO. THIS IS TO PERSIST OVER THE NEXT FEW
DAYS. AS THE RIDGE HOLDS...IT IS TO STEER TUTTS AND TUTT LOWS
ACROSS NORTHERN CENTRAL AMERICA-CENTRAL MEXICO. IN THIS PATTERN...
ONE IS PULLING ACROSS COLIMA MEXICO AS ANOTHER RETROGRESSES ACROSS
BELIZE TO GUATEMALA/THE YUCATAN EARLY IN THE CYCLE. THROUGH 48-60
HRS THE LATTER VORTEX MOVES TO THE CENTRAL STATES OF MEXICO...AND
BY 84-96 HRS IT IS TO CLEAR THE COAST OF COLIMA/SINALOA. THE
INFLOW OF COLD AIR/SHORT WAVE ENERGY ALOFT WILL ENHANCE DIURNAL
CONVECTION. ACROSS GUATEMALA-BELIZE-THE YUCATAN/SOUTHERN MEXICO IT
IS TO FAVOR RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF
20-35MM/DAY THROUGH 36-42 HRS...WHILE ON THE SOUTHERN-CENTRAL
STATES OF MEXICO IT IS TO FAVOR RAINFALL AMOUNTS OF 15-20MM/DAY
AND MAXIMA OF 25-50MM BY 36-60 HRS. THROUGH 72-96 HRS MAXIMA
DECREASES TO 20-40MM. OTHER ACTIVITY TO THE NORTH IS TO BUILD
ALONG THE SIERRA MADRE OCCIDENTAL...WITH RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM/DAY...WITH A SLIGHT INCREASE BY
72-96 HRS.

ANOTHER TUTT LOW LIES FARTHER TO THE EAST...WITH AXIS
NORTH-TO-SOUTH ALONG 70W TO NORTHERN HISPANIOLA. UNDER INFLUENCE
OF THE RIDGE TO THE WEST THIS IS TO ALSO RETROGRESS TOWARDS THE
BAHAMAS-EASTERN CUBA EARLY IN THE CYCLE...WITH AXIS ANCHORING ON A
CLOSED LOW OVER THE CENTRAL BAHAMAS. AS THE TROUGH/LOW MEANDERS
WEST...THE BASE IS TO AMPLIFY ACROSS EASTERN CUBA TO THE NORTHERN
CARIBBEAN. THE TROUGH/LOW THEN REMAINS NEARLY STATIONARY THROUGH
66-72 HRS...AND LATER IN THE CYCLE IT WILL MOVE TOWARDS CENTRAL
CUBA. AS THE TROUGH MEANDERS TO THE NORTH SOME CONVECTIVE
ENHANCEMENT IS POSSIBLE ACROSS WESTERN PORTIONS OF THE DOMINICAN
REPUBLIC WHERE IT IS TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15-20MM/DAY. MOST ACTIVE...HOWEVER...IS EXPECTED OVER
THE SOUTHEAST-CENTRAL BAHAMAS...WHERE THE TROUGH ALOFT IS TO
INTERACT WITH REMNANTS OF TS DORIAN TO SUSTAIN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM. THROUGH 72-96 HRS THIS IS TO
SPREAD INTO THE NORTHWEST BAHAMAS WHERE IT IS TO FAVOR RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM/DAY. ACROSS CUBA
INITIALLY EXPECT RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF
20-30MM. THROUGH 48-60 HRS THIS WILL INCREASE TO 15-20MM/DAY AND
MAXIMA OF 25-50MM/DAY. THIS WILL PERSIST THROUGH DAY 03 AS
ACTIVITY BUILDS WEST ACROSS CUBA. OTHER ENHANCEMENT TO THE SOUTH
IS EXPECTED ACROSS JAMAICA ON DAY 01...AS TROUGH ALOFT ENHANCES
SEA BREEZE CONVERGENCE TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY
AND MAXIMA OF 15-20MM/DAY.

AFOREMENTIONED TUTT LOW OVER THE WESTERN CARIBBEAN IS INTERACTING
WITH THE EASTERN PACIFIC ITCZ IN SUPPORT OF ORGANIZED DEEP
CONVECTION ACROSS NICARAGUA TO NORTHEAST HONDURAS...WHERE IT IS TO
FAVOR RAINFALL AMOUNTS OF 15-30MM/DAY AND MAXIMA OF 40-80 THROUGH
24-30 HRS. BUT AS THE LOW PULLS AWAY...THIS WILL GRADUALLY
DECREASE TO 05-10MM/DAY AND MAXIMA OF 15-20MM BY 72-96 HRS. ACROSS
WESTERN TO NORTHERN COLOMBIA EQUATORIAL TROUGH RELATED CONVERGENCE
IS TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-30MM.
AN INCREASE IN ACTIVITY IS POSSIBLE IN THIS AREA BY 48-72 HRS AS
TUTT PATTERN OVER THE CENTRAL CARIBBEAN BECOMES BETTER
ORGANIZED...WITH MAXIMA TO INCREASE TO 25-50MM. ACROSS VENEZUELA
EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM/DAY...SIMILARLY OVER THE NORTHERN GUIANAS

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL 24 36 48 60 72 84 96 TYPE
32W 36W 39W 42W 45W 49W 52W 56W TW
42W 45W 48W 51W 55W 59W 62W 65W TUTT INDCD/EW
66W 69W 72W 76W 79W 82W 85W 88W TW
83W 86W 90W 94W 98W 101W 104W 108W TW
91W 95W 98W 102W 106W 109W 112W EXITS TUTT INDCD/EW

TROPICAL WAVE ALONG 32W IS TO ENTER FRENCH GUIANA BY 84-96
HRS...WHERE IN INTERACTION WITH THE ITCZ IT IS TO SUSTAIN RAINFALL
AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM/DAY.

A TUTT INDUCED TROUGH IN THE EASTERLIES IS INITIALIZED ALONG 42W.
THIS IS TO GENERALLY REMAIN NORTH OF THE GUIANAS AS IT MOVES
TOWARDS THE EASTERN CARIBBEAN ISLES THROUGH 72/78 HRS. AS IT
ENTERS THE ISLAND CHAIN THIS IS TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-20MM/DAY...WITH ACTIVITY TO BUILD
WEST ACROSS THE VIRGIN ISLES-PUERTO RICO BY 72-84 HRS. POSITIVE
INTERACTION WITH THE ITCZ IS TO LIMIT TO NORTHERN GUYANA ON DAY
03...WHEN IT IS TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15MM/DAY.

TS DORIAN WEAKENED TO A TROPICAL WAVE ALONG 66W. A MOIST TONGUE
TRAILS TO THE EAST...AND IT IS TO ENTER THE LEEWARD ISLES LATER
THIS AFTERNOON...AND INTO THE VIRGIN ISLES TO PUERTO RICO BY
MIDDAY ON TUESDAY. THIS IS TO THEN FAVOR RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-30MM. THE WAVE...MEANWHILE...IN
INTERACTION WITH TUTT NORTH OF HISPANIOLA IT IS TO SUSTAIN
ORGANIZED DEEP CONVECTION NORTH OF THE GREATER ANTILLES. OVER THE
SOUTHEAST BAHAMAS/TURKS IT IS TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM THROUGH 36-42 HRS...WHILE OVER THE
CENTRAL BAHAMAS EXPECTING ACCUMULATION OF 10-15MM/DAY AND MAXIMA
OF 20-35MM BY 48 HRS. OVER THE NORTHWEST BAHAMAS-CENTRAL/WESTERN
CUBA IT IS TO THEN FAVOR RAINFALL AMOUNTS OF 15-20MM/DAY AND
MAXIMA OF 25-50MM BY 72-84 HRS. THROUGH 96 HRS EXPECTING
CONVECTION TO WANE...WITH ACCUMULATION OF 10-15MM/DAY AND MAXIMA
OF 20-40MM OVER WESTERN CUBA...WHILE OVER THE NORTHWEST BAHAMAS
EXPECTING 05-10MM/DAY AND MAXIMA OF 15MM. OVER NORTHWEST VENEZUELA
TO NORTHERN COLOMBIA...IN INTERACTION WITH THE NEAR EQUATORIAL
TROUGH...EXPECTING ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF
20-35MM/DAY...WHILE OVER WESTERN COLOMBIA TO EASTERN PANAMA
EXPECTING ACCUMULATION OF 15-20MM/DAY AND MAXIMA OF 25-50MM. OVER
WESTERN PANAMA TO COSTA RICA/EASTERN NICARAGUA IT IS TO THEN
SUSTAIN RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM/DAY.
OVER NORTHERN CENTRAL AMERICA THIS WILL DECREASE TO 05-10MM/DAY
AND MAXIMA OF 15-20MM BY 96-108 HRS.

TROPICAL WAVE ALONG 83W IS IN PHASE WITH TUTT OVER THE YUCATAN. AS
THEY INTERACT...EXPECTING CONVECTION ACROSS NORTH
CENTRAL-NORTHWESTERN HONDURAS-BELIZE AND GUATEMALA TO FLARE
UP...TO SUSTAIN ACCUMULATION OF 15-30MM/DAY AND MAXIMA OF 40-80MM.
ACROSS GUATEMALA TO SOUTHERN MEXICO IT IS TO THEN FAVOR RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM BY 24-48 HRS...TO
GRADUALLY BUILD WEST INTO CENTRAL MEXICO THROUGH 72-84 HRS WITH
ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF 20-40MM.

TUTT INDUCED WAVE ALONG 91W IS TO ENHANCE LOW LEVEL MOISTURE
CONVERGENCE ACROSS THE SOUTHERN TO CENTRAL STATES OF MEXICO...
WHERE IT IS TO RESULT IN RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15-25MM.

MCKENZIE...BDM (BAHAMAS)
ROBINSON...MSJ (JAMAICA)
DAVISON...WPC (USA)

[cycloneye]

Good morning. Good weather will prevail in PR for the next few days with only the usual afternoon showers in the interior. It will be warm too.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
522 AM AST TUE JUL 30 2013

.SYNOPSIS...TUTT LOW NORTH OF HISPANIOLA WILL PERSIST NEAR OR OVER
THE GREATER ANTILLES FOR THE NEXT SEVERAL DAYS. A SECOND AND
STRONGER TUTT LOW WILL DEVELOP ACROSS THE CENTRAL ATLANTIC BY THE
MIDDLE OF THE WEEK. A TROPICAL WAVE...REMNANTS OF TROPICAL STORM
DORIAN...JUST NORTH OF HISPANIOLA THIS MORNING...WILL CONTINUE TO
MOVE WESTWARD AND AWAY FROM THE LOCAL ISLANDS TODAY.

&&

.DISCUSSION...DOPPLER WEATHER RADAR DETECTED ISOLATED TO SCATTERED
SHOWERS MOVING WESTWARD ACROSS THE COASTAL WATERS OVERNIGHT AND
EARLY IN THE MORNING. A CLUSTER OF STRONG THUNDERSTORMS...ASSOCIATED
WITH THE TROPICAL WAVE...REMNANT OF DORIAN...WAS ALSO DETECTED
NORTHWEST OF PUERTO RICO...WELL OUTSIDE OF OUR COASTAL WATERS.
MINIMAL SHOWER ACTIVITY...IF ANY...WAS OBSERVED OVER LAND AREAS SO
FAR THIS MORNING. THE TROPICAL WAVE WILL CONTINUE TO MOVE WESTWARD
AWAY FROM THE LOCAL ISLANDS TODAY. FOR THE NEXT SEVERAL DAYS
THE TYPICAL SUMMER TIME WEATHER PATTERN IS EXPECTED TO CONTINUE
ACROSS THE LOCAL ISLANDS...WITH NIGHTTIME ISOLATED TO SCATTERED
PASSING SHOWERS ACROSS THE USVI AND EASTERN PUERTO RICO AND DIURNAL
INDUCED SHOWER AND THUNDERSTORM ACTIVITY ACROSS WESTERN AND INTERIOR
PUERTO RICO EACH AFTERNOON. NO MAJOR CHANCES IN THIS WEATHER PATTERN
ARE EXPECTED IN THE FORESEEABLE FUTURE. THE TUTT LOW JUST NORTH
OF HISPANIOLA THIS MORNING IS EXPECTED TO PERSIST ACROSS THE
GREATER ANTILLES FOR THE NEXT SEVERAL DAYS. A SECOND AND STRONGER
TUTT LOW WILL DEVELOP ACROSS THE TROPICAL ATLANTIC...NORTHEAST OF
THE REGION...BY THE MIDDLE OF THE WEEK.

&&

.AVIATION...VFR CONDS EXPECTED ACROSS ALL THE LOCAL TAF SITES
THROUGH THE FORECAST PERIOD. HOWEVER...VICINITY SHOWERS WILL AFECTED
FROM TIME TO TIME THE TKPK AND TNCM SITES. LLVL WINDS WILL BE MAINLY
FM THE ESE TO SE AT AROUND 5-10 KTS.

&&

.MARINE...SEAS OF UP TO 5 FEET AND WINDS OF 17 KNOTS OR LESS ARE
EXPECTED OVER THE COASTAL WATERS TODAY. HIGHER WINDS AND SEAS ARE
POSSIBLE NEAR THUNDERSTORMS MOSTLY ACROSS THE ATLANTIC WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 77 88 78 / 30 30 30 20
STT 89 78 89 79 / 40 40 40 20

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
252 PM AST TUE JUL 30 2013

.SYNOPSIS...PUERTO RICO AND THE USVI LIES BETWEEN TWO UPPER LEVEL
TROUGH... ONE NEAR BAHAMAS AND THE OTHER OVER THE CENTRAL ATLANTIC.
AT LOW LEVELS...A TRAILING NARROW BAND OF MOISTURE CONNECTED WITH
THE REMNANTS OF DORIAN PRODUCED SCATTERED THUNDERSTORMS ACROSS
PORTIONS OF THE ISLANDS AND THE SURROUNDING WATERS TODAY. MOISTURE
CONTENT WILL DIMINISH QUICKLY THIS EVENING BUT INCREASES AGAIN ON
THURSDAY.

&&

.DISCUSSION...SATELLITE DERIVED PWAT ANALYSIS SHOWED A NARROW MOIST
BAND ACROSS THE NORTHEAST CARIBBEAN TODAY. THIS HIGH MOISTURE CONTENT
COMBINED WITH MARGINAL UPPER DYNAMICS TO FUEL SCATTERED CONVECTION
ACROSS PUERTO RICO AND THE USVI EARLY TODAY. CLUSTERS OF SHOWERS
WITH A COUPLE OF STRONG THUNDERSTORMS MOVED ACROSS PUERTO RICO
LATE IN THE MORNING AND EARLY AFTERNOON. THE MOST INTENSE STORMS
WERE OBSERVED ACROSS THE INTERIOR AND WEST SECTIONS OF PUERTO RICO
AS WELL AS THE SOUTHERN PORTIONS OF THE SAN JUAN METRO AREA. RAINFALL
AMOUNTS OVER ONE INCH WERE ESTIMATED ALONG THE VICINITY OF MAYAGUEZ
AND BETWEEN THE BORDER OF GURABO...TRUJILLO ALTO AND SAN JUAN.

SATELLITE IMAGERY AS WELL AS MODEL GUIDANCE SUGGEST RELATIVELY
DRIER CONDITIONS STARTING THIS EVENING AND CONTINUING THROUGH
WEDNESDAY. THE LACK OF MOISTURE WILL LIMIT THE SHOWER COVERAGE
TOMORROW AFTERNOON ACROSS WESTERN PUERTO RICO. AN EASTERLY
PERTURBATION INDUCED BY THE UPPER LEVEL TROUGH NORTHEAST OF THE
REGION WILL CROSS THE FORECAST AREA ON THURSDAY. THIS FEATURE WILL
BRING ENOUGH MOISTURE AND INSTABILITY TO SUSTAIN THE DEVELOPMENT
OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE ISLANDS. THE
NEXT TROPICAL WAVE IS FORECAST TO ENTER THE EASTERN CARIBBEAN ON
SATURDAY. LATEST SYNOPTIC GUIDANCE THAT THE MOISTURE ASSOCIATED
WITH THE WAVE WILL REMAIN MAINLY SOUTH OF THE LOCAL AREA.

&&

.AVIATION...VFR CONDITIONS NEXT 24 HRS EXCEPT AT JMZ WHERE A TSRA IS
POSSIBLE.

&&

.MARINE...WINDS AND SEAS WILL REMAIN BELOW THE SCA CRITERIA
THROUGH AT LEAST NEXT WEEK. MODERATE WINDS AND SEAS BETWEEN 3-5 FT
WILL PREVAIL ACROSS THE REGIONAL WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 79 88 79 89 / 20 20 20 20
STT 77 87 78 89 / 20 20 30 30

[cycloneye]

Good morning. A trough will bring scattered showers today thru tomorrow for PR and adjacent islands.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
448 AM AST WED JUL 31 2013

.SYNOPSIS...AT UPPER LEVELS...HIGH PRESSURE BETWEEN TWO TUTTS
NORTHWEST AND NORTHEAST WILL PREVAIL UNTIL SUNDAY. THEN A TROUGH
FROM THE NORTHEAST TUTT WILL EXTEND OVER THE LOCAL AREA AND DRIFT
NORTHWEST. THIS WILL BRING A MILD JET FROM THE SOUTHWEST OVER THE
AREA BEGINNING MONDAY. BY LATE NEXT WEEK HIGH PRESSURE WILL NOSE
IN FROM THE TROPICAL ATLANTIC.

AT MID LEVELS...AN INVERTED TROUGH IN THE WESTERN TROPICAL
ATLANTIC WILL MOVE WEST INTO THE EASTERN CARIBBEAN...BUT WILL BE
LARGELY DISSIPATED BY THE TIME IT ARRIVES HERE THURSDAY NIGHT.
STRONG HIGH PRESSURE IN THE EASTERN ATLANTIC BETWEEN 20 AND 30
NORTH WILL MOVE WEST...PASSING NORTH OF THE LOCAL AREA ON
SATURDAY MORNING. LOW PRESSURE WILL DRIFT IN BEHIND IT SUNDAY
THROUGH TUESDAY. ALTHOUGH MID LEVELS ARE NOT COMPLETELY
DRY...MOISTURE IS NOT ABUNDANT DURING THE NEXT 7 DAYS.

AT LOWER LEVELS...A WEAK TROUGH IS ENTERING THE LEEWARD ISLANDS
FROM THE EAST NORTHEAST AND WILL PASS OVER PUERTO RICO THIS
AFTERNOON WITH AN INCREASE IN MOISTURE AFTER A SHORT-LIVED DRY
SLOT EARLY THIS MORNING. THEN ON FRIDAY AND SATURDAY HIGH PRESSURE
WILL CAUSE A MODERATE WIND SURGE FROM THE SOUTHEAST...ESPECIALLY
ABOVE 850 MB ...OR ABOUT 5 THOUSAND FEET. THE NEXT WAVE WILL
ARRIVE MID WEEK NEXT WEEK...BUT WILL BE SOMEWHAT DISORGANIZED.

&&

.DISCUSSION...DESPITE A DECLINE IN PRECIPITABLE WATER WHICH
DROPPED FROM 2.0 INCHES YESTERDAY AFTERNOON TO 1.3 INCHES EARLY
THIS MORNING IN SAINT CROIX...SOME SHALLOW SHOWERS WERE NOTED ON
NATIONAL WEATHER SERVICE DOPPLER RADAR OVER BOTH THE ATLANTIC AND
CARIBBEAN WATERS MOVING IN FROM THE EAST NORTHEAST. SOME OF THESE
SHOWERS MOVED ONSHORE AS DEEPLY AS VILLALBA AND OROCOVIS IN
PUERTO RICO. AMOUNTS WERE SLIGHT HOWEVER. THE GFS IS SHOWING A WEAK
TROUGH APPROACHING THE LOCAL AREA AND THE MIMIC PRODUCT IS
CONFIRMING AN EARLIER ARRIVAL THAN FIRST ANTICIPATED...WITH
MOISTURE ARRIVING IN THE U.S. VIRGIN ISLANDS THIS MORNING AND THE
EASTERN HALF OF PUERTO RICO EARLY THIS AFTERNOON. THIS IS EXPECTED
TO BRING A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS TO INTERIOR
PUERTO RICO BY LATE MORNING OR EARLY AFTERNOON. THE EVOLUTION OF
THIS BAND ON THE MIMIC PRODUCT SUGGESTS THAT SOME OF THIS MOISTURE
WILL LAST THROUGH THURSDAY AFTERNOON...SUCH THAT SCATTERED SHOWERS
WILL CONTINUE OVERNIGHT TONIGHT IN MUCH OF PUERTO RICO AND THE
U.S. VIRGIN ISLANDS AND CONTINUE INTO THURSDAY. AT THIS
TIME...NEVERTHELESS...URBAN AND SMALL STREAM FLOODING IS ONLY
EXPECTED IN ISOLATED AREAS. AS HAS OCCURRED IN PREVIOUS
AFTERNOONS...FREQUENT LIGHTING SHOULD BE EXPECTED WHERE
THUNDERSTORMS DEVELOP. WINDS WILL TURN SOUTHEAST JUST ABOVE THE
SURFACE ON THURSDAY AND THIS COULD BRING SLIGHTLY WARMER
TEMPERATURES FRIDAY AND SATURDAY. THE GFS AND THE ECMWF APPEAR TO
AGREE AS 1000-850 MB THICKNESSES ARE HIGHEST OF THE NEXT 10 DAYS
OVER THE WEEKEND FRIDAY THROUGH SUNDAY. ALSO WITH WINDS JUST ABOVE
THE SURFACE TURNING SOUTHEAST THIS COULD CAUSE TEMPERATURES IN THE
LOWER 90S FOR THE GREATER SAN JUAN METRO AREA AND COASTAL
VICINITIES...UNTIL THE SEA BREEZE CAN BREAK THROUGH. AT PRESENT
THE 31/00Z GFS MODEL RUN SUGGESTS BEST MOISTURE ON THURSDAY OF
THIS WEEK AND NEXT WITH FRIDAY NIGHT THIS WEEK AND FRIDAY OF NEXT
WEEK SHOWING THE DRIEST AIR...WITH SUNDAY NIGHT A CLOSE SECOND.
THUNDERSTORM ACTIVITY IS LIKELY TO BE ENHANCED AS UPPER LEVEL
WINDS INCREASE ON THE SOUTHEAST SIDE OF THE TROUGH THAT EXTENDS
SOUTHEAST OVER THE AREA EARLY NEXT WEEK.

&&

.AVIATION...
VFR CONDS EXPECTED THIS MORNING ACROSS THE LOCAL TAF SITES WITH A
FEW PASSING SHRA ACROSS TSJU...TIST AND TNCM SITES. VFR CONDS DURG
PD WITH THE EXCEPTION OF VCNTY TJBQ/TJMZ AFTER 31/15Z WHERE DIURNAL
INDUCED CONVECTION TILL AT LEAST 31/23Z IS EXPECTED.

&&

.MARINE...SEAS REMAIN BELOW EXERCISE CAUTION LEVELS...THOUGH WINDS
ARE EXPECTED TO BECOME GREATER THAN 17 KNOTS WHEN THE WIND SURGE
ARRIVES FRIDAY AND SATURDAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 79 89 78 / 30 50 70 50
STT 88 79 89 80 / 20 60 50 50

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
258 PM AST WED JUL 31 2013

.SYNOPSIS...NARROW UPPER LEVEL RIDGE BETWEEN TWO TUTTS NORTHWEST AND
NORTHEAST WILL PREVAIL THROUGH THE END OF THE WEEK. THE UPPER LEVEL
TROUGH...TUTT...TO THE NORTHEAST WILL DRIFT WEST EARLY NEXT WEEK PASSING
NORTH OF THE ISLANDS. A TUTT INDUCED SFC TROUGH WILL MOVE ACROSS THE
LOCAL REGION TODAY...DISSIPATING DURING THE NEXT 24-48 HOURS. A DENSE
AND BROAD AREA OF SAHARAN DUST OVER THE TROPICAL ATLANTIC WILL ARRIVE
LATE FRIDAY THROUGH EARLY SATURDAY MORNING.

&&

.DISCUSSION...SATELLITE IMAGERY AS WELL AS MODEL GUIDANCE SUGGEST A
WEAK SFC TROUGH INDUCED BY THE TUTT...MOVING ACROSS THE NORTHEAST
CARIBBEAN ISLANDS TODAY. SATELLITE DERIVED PWAT ANALYSIS SHOWS
PRECIPITABLE WATER VALUES OVER 2 INCHES ACCOMPANIED THIS INDUCED
TROUGH. THIS FEATURE HAS INDUCED A CLUSTER OF THUNDERSTORMS OVER
THE ANEGADA PASSAGE AND THE OFFSHORE ATLANTIC WATERS NORTH OF ST.
JOHN/ST. THOMAS MOST OF THE DAY. NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS DEVELOPED ACROSS THE INTERIOR...SOUTH AND WEST
PORTIONS OF PUERTO RICO THIS AFTERNOON. THE MOIST AND UNSTABLE AIR
MASS ASSOCIATED WITH THE TROUGH WILL CONTINUE TO MOVE ACROSS THE
FORECAST AREA TONIGHT THROUGH EARLY THURSDAY...GENERATING A FEW
ROUND OF SCATTERED SHOWERS AND SOME THUNDERSTORMS ACROSS THE LOCAL
WATERS AS WELL AS PORTIONS OF THE USVI...CULEBRA...VIEQUES AND
EASTERN PUERTO RICO. MOISTURE CONTENT WILL DECREASE RAPIDLY BY
FRIDAY AS A VERY DENSE LAYER OF SAHARAN DUST ARRIVES INTO OUR
REGION. THIS IS A FAIRLY WIDE AREA WITH THE DUST WILL PRODUCE
REDUCED VISIBILITIES AND IT SHOULD LIMIT THE POTENTIAL FOR
CONVECTION ACROSS THE FORECAST AREA FRIDAY INTO THE WEEKEND. THIS
BROAD AREA OF SAHARAN DUST IS LIKELY TO AFFECT THE FORECAST AREA
FOR SEVERAL DAYS. SYNOPTIC MODELS SUGGEST THAT THE NEXT TROPICAL
WAVE WILL ENTER THE EASTERN CARIBBEAN BY SUNDAY/MONDAY...HOWEVER...
WE DO NOT EXPECT MUCH ACTIVITY WITH THIS WAVE AT THIS MOMENT.

&&

.AVIATION...TSTMS POSSIBLE AT JSJ...JMZ...USVI AND LEEWARD ISLAND
TERMINALS WITH MVFR NEXT 24 HR. WILL KEEP VCTS AT THESE AIRPORTS
FOR THE NEXT 24 HRS. FRIDAY...CONDITIONS IMPROVING MARKEDLY HOWEVER
A DENSE LAYER OF SAHARAN DUST IS EXPECTED TO ARRIVE FRI NIGHT AND
IS LIKELY TO RESULT IN 5-6SM VSBYS.

&&

.MARINE...SCT THUNDERSTORMS THE MAIN HAZARD TODAY THROUGH THU.
MODERATE WINDS AND SEAS OF 3-5 FT WILL PREVAIL THROUGH THE END OF
THE WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 78 88 78 90 / 40 40 20 20
STT 78 88 80 90 / 50 50 40 40

[Macrocane]

Latest HPC Discussion, it seems that SAL and dry air is coming our way:

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
213 PM EDT WED JUL 31 2013

DISCUSSION FROM JULY 31/00UTC: GOOD CONTINUITY OVER WESTERN
PORTIONS OF THE DOMAIN...WITH MODELS INITIALIZING A BUILDING
RIDGE. THE RIDGE ANCHORS AT 250 HPA ON A CLOSED HIGH OVER WESTERN
TEXAS. RIDGE AXIS IS FORECAST TO GRADUALLY BUILD SOUTH AND EAST
THROUGH 60-72 HRS. AS THE RIDGE BUILDS...EXPECTING IT TO GRADUALLY
STRENGTHEN SUBSIDENCE CAP ACROSS MEXICO. THIS IS TO THEN SUSTAIN A
GRADUAL DRYING TREND ALONG THE SIERRA MADRE OCCIDENTAL. EARLY IN
THE CYCLE EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF
20-30MM/DAY. THROUGH 72-96 HRS THIS WILL DECREASE TO 05-10MM/DAY
AND MAXIMA OF 15MM/DAY. A RETROGRESSING TUTT LOW LIES TO THE
SOUTH...WITH CLOSED LOW MIGRATING ACROSS THE CENTRAL MEXICO EARLY
IN THE CYCLE. THROUGH 24-36 HRS IT IS TO RELOCATE JUST WEST OF
COLIMA/SINALOA...TO THEN DRIFT WEST INTO THE EASTERN PACIFIC.
EARLY IN THE CYCLE THIS TROUGH IS TO ENHANCE CONVECTION ACROSS THE
CENTRAL STATES OF MEXICO...TO FAVOR RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-40MM.

ANOTHER TUTT LOW LIES FARTHER TO THE EAST...WITH CLOSED LOW NEAR
25W 73W EXTENDING A TROUGH ACROSS THE BAHAMAS-CUBA TO THE
NORTHWEST CARIBBEAN. THIS IS A FAIRLY DEEP PERTURBATION...HAVING A
STRONG MID LEVEL REFLECTION. AT LOW LEVELS IT REFLECTS AS AN
INVERTED TROUGH IN THE EASTERLY TRADES...WITH AXIS MEANDERING
ACROSS CENTRAL/WESTERN CUBA. MID/UPPER LEVEL CIRCULATION IS TO
DRIFT ACROSS THE CENTRAL BAHAMAS BY 30-42 HRS...INTO CENTRAL CUBA
BY 48-60 HRS...WHERE IT IS FORECAST TO STALL. AS IT PRESSES
AGAINST THE RIDGE TO THE WEST...MODELS SHOW MID/UPPER TROUGH
GRADUALLY BECOMING NEGATIVELY TILTED WITH HEIGHT THROUGH 36-48
HRS. AS A RESULT...AREAS OF DIVERGENCE WILL TEND TO SHIFT FROM
EASTERN HALF OF THIS TROUGH TO THE WESTERN SIDE. ACROSS CUBA THIS
IS TO FAVOR RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA OF
25-50MM/DAY IN POTENTIALLY SEVERE CONVECTION DURING THE NEXT 24-36
HRS. THROUGH 48-72 HRS THIS DECREASES TO 10-15MM/DAY AND MAXIMA OF
20-30MM. ACROSS THE SOUTHEAST-CENTRAL BAHAMAS EXPECTING RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM/DAY THROUGH 36
HRS...WHILE OVER THE NORTHWEST BAHAMAS THIS IS EXPECTED TO PEAK AT
15-20MM/DAY AND MAXIMA OF 25-50MM BY 36-60 HRS. THIS THEN
DECREASES TO 05-10MM/DAY AND MAXIMA OF 15-30MM BY 60-84 HRS.

A THIRD TUTT LOW CENTERING NEAR 26N 52W EXTENDS A TROUGH TO THE
SOUTHWEST INTO THE NORTHEAST CARIBBEAN ISLES. THIS REFLECTS AS AN
INVERTED TROUGH IN THE MID/LOW LEVELS OF THE ATMOSPHERE. THE UPPER
LEVEL TROUGH PATTERN IS TO GENERALLY PERSIST OVER THE NEXT FEW
DAYS...WITH AXIS TO REMAIN NEARLY STATIONARY. AT MID LEVELS...AS A
RIDGE BUILDS FROM THE EAST...THE INVERTED TROUGH WILL START TO
MIGRATE TOWARDS THE EASTERN CARIBBEAN ISLES EARLY IN THE
CYCLE...MEANDERING ACROSS THE VIRGIN ISLES TO PUERTO RICO BY 48-54
HRS. BUT AS IT DECOUPLES FROM THE TUTT ALOFT...THE INVERTED MID
LEVEL TROUGH IS THEN FORECAST TO RAPIDLY FILL THROUGH 60-72 HRS.
MEANWHILE...THIS IS TO ENHANCE CONVECTIVE DEVELOPMENT ACROSS THE
NORTHEAST CARIBBEAN ISLES...TO FAVOR RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM/DAY.

BUILDING CELL OF THE SUBTROPICAL RIDGE IS TO THEN BECOME DOMINANT
FEATURE ACROSS THE ATLANTIC INTO THE CARIBBEAN BASIN. THROUGH 72
HRS THE RIDGE IS TO GRADUALLY AMPLIFY ACROSS THE GREATER ANTILLES
INTO THE NORTHERN CARIBBEAN AND THE BAHAMAS. AT LOW LEVELS THE
RIDGE IS TO INITIALLY CENTER ON A CLOSED HIGH NEAR 30N 45W. THIS
RELOCATES TO 30N 60W THROUGH 72-84 HRS. AS THE RIDGE RELOCATES AND
BUILDS ACROSS THE BASIN...IT IS TO TIGHTEN THE PRESSURE GRADIENT.
THIS...IN-TURN...WILL SUSTAIN A WIND SURGE ACROSS THE ISLAND CHAIN
THROUGH 36-48 HRS...TO THEN QUICKLY EXPAND ACROSS THE
CENTRAL/SOUTHERN CARIBBEAN THROUGH 60-72 HRS. AT 850 WINDS ACROSS
THE LESSER ANTILLES TO EASTERN CARIBBEAN ARE TO PEAK AT
25-30KT...WHILE OVER THE CENTRAL AND SOUTHERN CARIBBEAN THEY WILL
PEAK AT 45-50KT. THE STRONG WINDS ARE TO ADVECT A SAHARAN AIR
LAYER ACROSS THE TROPICAL ATLANTIC INTO THE CARIBBEAN LATER THIS
WEEK...TO RAPIDLY SPREAD ACROSS THE BASIN. STRENGTHENING TRADES
WIND CAP IS TO SUSTAIN A DRYING TREND ACROSS THE LESSER ANTILLES/
NORTHERN CARIBBEAN ISLES...TO THEN EXPAND ACROSS THE CENTRAL
CARIBBEAN TO PORTIONS OF CENTRAL AMERICA LATER IN THE CYCLE.

MEANWHILE... ITCZ RELATED CONVERGENCE ACROSS SOUTHERN
NICARAGUA-COSTA RICA WILL SUSTAIN RAINFALL AMOUNTS OF 15-20MM/DAY
AND MAXIMA OF 40-80MM THROUGH 36 HRS. AS DRYER AIR ADVECTS ACROSS
THE BASIN THIS WILL DECREASE TO 10-15MM/DAY AND MAXIMA OF 20-30MM
THROUGH 72-96 HRS. NOTE THAT WE ARE FORECASTING LESSER AMOUNTS
THAN WHAT THE GFS SUGGESTS. UNDER INFLUENCE OF THE PANAMANIAN
LOW...ACROSS WESTERN-NORTHERN COLOMBIA TO PANAMA EXPECTING
RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-40MM. THIS IS TO
ALSO DECREASE TO 10-15MM/DAY AND MAXIMA OF 20-30MM BY 72-96 HRS.
ACROSS VENEZUELA EXPECTING RAINFALL AMOUNTS OF 05-10MM/DAY AND
MAXIMA OF 15-20MM...WITH A GRADUAL INCREASE IN ACTIVITY THROUGH
48-60 HRS WITH ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15-30MM.
OVER SOUTHERN COLOMBIA TO AMAZONIA IN VENEZUELA EXPECT RAINFALL
AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM...WHILE OVER THE
NORTHERN GUIANAS ATLANTIC ITCZ IS TO FAVOR RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-20MM/DAY.

TROPICAL/EASTERLY WAVES INITIALIZED AT 12UTC
INITIAL 24 36 48 60 72 84 96 TYPE
32W 36W 39W 43W 46W 50W 54W 58W TW
48W 52W 55W 59W 62W 66W 69W 72W TW
53W 56W 60W 63W 66W 69W 72W 75W TUTT INDCD/EW
79W 82W 85W 89W 92W 96W 99W 103W TW
98W 102W 105W 109W 112W 114W EXITS TUTT INDCD/EW

TROPICAL WAVE ALONG 32W IS TO ENTER FRENCH GUIANA BY 72 HRS...TO
MOVE ACROSS SURINAME TO GUYANA THROUGH 96 HRS. AS IT INTERACTS
WITH THE ATLANTIC ITCZ THIS IS TO SUSTAIN RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15MM/DAY.

THE TROPICAL WAVE ALONG 48W CONTINUES TO DAMPEN AS A HIGH
AMPLITUDE RIDGE BUILDS TO THE NORTH ACROSS THE CENTRAL-TROPICAL
ATLANTIC. BY 36-42 HRS THE WEAK PERTURBATION ENTERS FRENCH GUIANA
WHERE IT IS TO FAVOR RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-25MM. BY 54-60 HRS IT IS TO ENTER NORTHERN GUYANA/NORTHEAST
VENEZUELA-SOUTHERN WINDWARD ISLANDS...TO TRIGGER RAINFALL AMOUNTS
OF 05-10MM/DAY AND MAXIMA OF 15-20MM/DAY. SIMILARLY ACROSS
VENEZUELA BY 72-84 HRS.

TUTT INDUCED PERTURBATION ALONG 53W ENTERS THE ISLAND CHAIN LATER
THIS EVENING...TO SUSTAIN RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-35MM. ACROSS PUERTO RICO TO THE DOMINICAN REPUBLIC
EXPECTING ACCUMULATION OF 05-10MM/DAY AND MAXIMA OF 15-20MM BY
48-60 HRS. THROUGH 72-96 HRS THIS WILL MOVE INTO EASTERN CUBA WITH
SIMILAR AMOUNTS.

TROPICAL WAVE ALONG 79W CONTINUES TO INTERACT WITH TUTT LOW NEAR
THE BAHAMAS. OVER JAMAICA AND THE CAYMAN ISLES IT IS TO FAVOR
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15MM. MOST ACTIVE IS
EXPECTED TO THE NORTH ACROSS CUBA...WHERE IT WILL FAVOR RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM/DAY. ACROSS PANAMA TO
COSTA RICA/SOUTHERN NICARAGUA EXPECTING ACCUMULATION OF
15-20MM/DAY AND MAXIMA OF 40-80MM/DAY. OVER EL SALVADOR/WESTERN
HONDURAS TO GUATEMALA EXPECTING ACCUMULATION OF 05-10MM/DAY AND
MAXIMA OF 15-20MM BY 48-60 HRS. AS IT ENTERS SOUTHERN MEXICO IT IS
TO THEN SUSTAIN RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF
15-20MM/DAY...WHILE OVER CENTRAL MEXICO THE MAXIMA PEAKS AT
20-40MM.

TROPICAL WAVE ALONG 98W IS IN PHASE WITH TUTT OVER CENTRAL MEXICO.
AS THEY INTERACT...EXPECTING RAINFALL AMOUNTS OF 10-15MM/DAY AND
MAXIMA OF 20-40MM/DAY.

MCKENZIE...BDM (BAHAMAS)
ROBINSON...MSJ (JAMAICA)
DAVISON...WPC (USA)

[cycloneye]

Good morning. Scattered showers will move thru PR today as a weak through swings westward.Hazy conditions will be present for the weekend.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
450 AM AST THU AUG 1 2013

.SYNOPSIS...AT UPPER LEVELS...THE TUTT TO THE NORTHEAST OF THE
AREA WILL EXTEND TOWARD THE AREA OVER THE WEEKEND AND EDGE TO THE
NORTHWEST BRINGING IN SOUTHWEST WINDS OVER THE LOCAL AREA MONDAY
AND TUESDAY. ALTHOUGH THE TROUGH WILL BREAK OVER THE LOCAL AREA
MID WEEK...IT RETURNS JUST NORTH OF THE FORECAST AREA OVER THE
FOLLOWING WEEKEND.

AT MID LEVELS...A WEAK TROUGH WILL MOVE OVER THE LOCAL AREA WHILE
DISSIPATING TODAY. HIGH PRESSURE IN THE CENTRAL ATLANTIC WILL
STRETCH OUT BETWEEN 20 AND 32 DEGREES NORTH BY SUNDAY AND
CONTINUE FOR MOST OF THE FOLLOWING WEEK. LIMITED MOISTURE WILL
CONTINUE AT MID LEVELS WITH THE BEST MOISTURE BEING FOUND TODAY
AND NOT AGAIN UNTIL FRIDAY OF NEXT WEEK.
AT LOWER LEVELS...HIGH PRESSURE CONTINUES OVER THE NORTHEAST
CENTRAL ATLANTIC WITH A RIDGE EXTENDING WEST SOUTHWEST TO FLORIDA
DURING THE ENTIRE PERIOD. THIS WILL MAINTAIN EASTERLY TRADE WIND
FLOW THROUGH THE PERIOD. A WEAK TROUGH WILL PASS THROUGH
TODAY...FOLLOWED BY A WIND SURGE CARRYING COPIOUS SAHARAN DUST
FRIDAY AND SATURDAY...TAPERING OFF ON SUNDAY. WINDS WILL BECOME
EAST NORTHEAST EARLY IN THE WEEK AS MID LEVEL HIGH PRESSURE MOVES
INTO THE BAHAMA ISLANDS. SOME MOISTURE IS BEING CARRIED IN THIS
AIR DESPITE THE DUST CONTENT. THE NEXT DISTURBANCE IS EXPECTED MID
WEEK NEXT WEEK.

&&

.DISCUSSION...SHOWERS...SOME HEAVY MOVED ACROSS NORTHEAST AND
SOUTHEAST PUERTO RICO EARLY THIS MORNING...LEAVING UP TO 1 INCH OF
RAIN IN A FEW PLACES IN THE LUQUILLO RANGE. SAN JUAN HAD ONE TENTH
INCH AT THE AIRPORT. THE SHOWERS HAVE BEEN MADE POSSIBLE BY A BAND
OF MOISTURE NOW MOVING WEST OVER THE LOCAL AREA. THIS BAND IS
EXPECTED TO CONTINUE OVER THE LOCAL AREA TODAY AND TONIGHT...WITH
SHOWERS TAPERING OFF OVERNIGHT TONIGHT. AN AREA OF DUST IS WELL
DEFINED IN SATELLITE IMAGES WITH THE DIFFUSE FORWARD BOUNDARY
BETWEEN 50 AND 55 DEGREES WEST LONGITUDE. AT ITS CURRENT SPEED THE
FIRST VESTIGES OF DUST WILL BE ARRIVING MID DAY ON FRIDAY. THE
DUST IS PUNCHING WEST ON THE STRENGTH OF THE TRADE WIND FLOW.
ORIGINALLY THE DUST MOVED OFF OF THE SAHARA ON MONDAY AND WAS
SUFFICIENTLY DENSE TO COLOR THE WATER BROWN EVEN AT MIDDAY IN THE
PSEUDO COLOR IMAGES. AS IT REACHED THE CAPE VERDE ISLANDS CLEAN
FLOW FROM HIGH PRESSURE OFF THE AFRICAN COAST CIRCULATED INTO THIS
FLOW CREATING WEAKER CONCENTRATIONS BETWEEN 15 AND 20 DEGREES
NORTH WHICH HAPPENS TO BE AT OUR LATITUDE. HENCE THE FAIRLY THICK
DUST WE WILL SEE FRIDAY NIGHT AND SATURDAY WILL NOT BE THE BEST
THIS AREA HAD TO DELIVER. THE GFS ALSO INDICATES THAT THERE WILL
BE SOME MOISTURE WITH THIS LAYER...MAINLY AT LOWER LEVELS...HAVING
BEEN PICKED UP DURING ITS LONG JOURNEY ACROSS THE ATLANTIC. THIS
WILL ALLOW SHOWERS AND THUNDERSTORMS TO BE GENERATED OVER THE
AREA THROUGH THE ENTIRE EPISODE...THOUGH MAINLY DURING THE
AFTERNOONS IN THE INTERIOR OF PUERTO RICO. OTHERWISE ONLY A FEW
SHOWERS WILL BE SEEN. AS HAS BEEN SEEN WITH PREVIOUS DUST EPISODES
FREQUENT LIGHTNING IS EXPECTED WHERE THUNDERSTORMS ARE GENERATED.
SHOWERS WILL TAPER OFF EARLY IN THE WEEK UNTIL THE NEXT WAVE
ARRIVES. THIS WILL COME SOMEWHAT DIVIDED TUESDAY NIGHT AND
WEDNESDAY AND IS NOT EXPECTED TO BE A MAJOR EVENT. ALSO AT THIS
TIME THE MODELS ARE NOT DEPICTING ANY CYCLONES TO DEVELOP FOR US
IN THE FLOW OUT OF THE AFRICAN CONTINENT THROUGH THE FIRST DOZEN
DAYS OF AUGUST.

FRIDAY WILL ALSO SEE SOME WARMING DUE TO A SHIFT TO THE EAST
SOUTHEAST OF THE WIND FLOW AND THE DEPARTURE OF THE SHOWER BEARING
MOISTURE BAND NOW MOVING THROUGH. TEMPERATURES ALONG MOST COASTS
WILL REACH THE 90S FRIDAY. WINDS WILL BE LIGHTER AND MORE
NORTHEASTERLY COME MONDAY.

&&

.AVIATION...
VFR CONDS EXPECTED THROUGH THE MORNING HOURS ACROSS THE
LOCAL TAF SITES. TSTMS POSSIBLE AT TJBQ AND TJMZ THIS AFTERNOON.
FRIDAY... CONDITIONS IMPROVING MARKEDLY HOWEVER A DENSE LAYER OF
SAHARAN DUST IS EXPECTED TO ARRIVE FRI NIGHT LOWERING THE VSBYS.
LLVL WINDS EAST TO SOUTHEAST 10 TO 20 KT.

&&

.MARINE...GENERALLY STEADY TRADE WIND FLOW WILL MAINTAIN SEAS OF 5
FEET OR LESS THROUGHOUT THE NEXT 7 DAYS...EXCEPT POSSIBLY 6 FEET
IN THE CARIBBEAN FRIDAY AND SATURDAY. WIND FLOW WILL INCREASE TODAY
THROUGH FRIDAY NIGHT WITH POCKETS OF 20 KNOTS LIKELY AROUND
NORTHWEST PUERTO RICO. MARINERS WILL SEE REDUCED VISIBILITIES THAT
MAY MAKE NAVIGATION BASED ON VISUAL SITING OF OBJECTS MORE THAN 7
MILES AWAY DIFFICULT TO IMPOSSIBLE.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 88 78 90 80 / 70 50 30 10
STT 88 79 90 81 / 70 50 40 20

[Macrocane]

Look at that massive SAL outbreak that's approaching the Caribbean, some of that dry air may even reach Central America next week:

[cycloneye]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
319 PM AST THU AUG 1 2013

.SYNOPSIS...TUTT LOW ACROSS THE CNTRL ATLC WILL BECOME THE
DOMINANT WX FEATURE OVR THE NEXT SVRL DAYS AND MOVE INTO
HISPANIOLA NEXT WEEK. UPPER LEVEL RIDGE WILL BUILD OVR THE REGION
MID NEXT WEEK. SAL WILL ESTABLISH OVR THE REGION OVR THE WEEKEND.

&&

.DISCUSSION...SAL ALREADY APPROACHING 60W THIS AFTERNOON BASED ON
ON CONVENTIONAL VIS IMAGERY AND MODIS AOD PRODUCTS. AREA WILL ALSO
BECOME UNDER UPPER LEVEL CONVERGENT SIDE OF TUTT ACROSS THE CNTRL
ATLC LEADING TO LARGE SCALE SUBSIDENCE AND DRYING. IN ADDITION...AREA
IS UNDER DOWNWARD PHASE OF MADDEN JULIAN OSCILLATION. ALL OF THESE
FACTORS WILL LEAD TO WELL BELOW NORMAL RAINFALL AND HOT TEMPERATURES
OVR THE NEXT 3-6 DAYS. NEXT FEATURE OF INTEREST IS TROPICAL WAVE
OVR THE ERN ATLC. THIS WAVE HAVE PLENTY OF DEEP CONVECTION AND IS
EMBBEDED IN VERY HIGH RELATIVE HUMIDITIES IN THE MID-UPPER TROPOSPHERE.
MODELS HAVE TRIED PAST FEW DAYS TO DEVELOP THIS WAVE BUT
APPARENTLY THE STRONG SAL LAYER AND DOWNWARD PHASE OF THE MJO WILL
BE BIG INHIBITING FACTORS. THIS WAVE LOOKS TO ARRIVE INTO OUR
AREA WED NIGH-THU AND BE OUR NEXT BEST CHANCE OF SIGNIFICANT RAINFALL.

&&

.AVIATION...MOST OF THE SHRA/TSRA ASSOCIATED WITH AN INDUCE TROUGH
THAT MOVED ACROSS THE FORECAST AREA TODAY DISSIPATED OR MOVED OVER
THE COASTAL WATERS. NO SIGNIFICANT SHWR ACTIVITY IS EXPECTED OVER
THE ISLANDS. THEREFORE...VFR CONDS ARE EXPECTED THROUGH THE NEXT 24
HOURS. HOWEVER...A DENSE LAYER OF SAHARAN DUST IS EXPECTED LATE
FRIDAY THAN COULD LOWER THE VSBYS.

&&

.MARINE...SEAS 3-5 FT AND WINDS UP TO 20 KT. DUST HAZE WILL BE
MAIN DOMINANT WX


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 80 88 82 90 / 10 10 10 10
STT 82 90 82 91 / 20 20 10 10

[msbee]

I just saw this video on the Huffington Post. I guess by tomorrow everything will be hazy

http://www.huffingtonpost.com/2013/08/0 ... nkusaolp00

definitely coming our way

[cycloneye]

I just saw this on the Huffington Post. I guess by tomorrow everything will be hazy

http://www.huffingtonpost.com/2013/08/0 ... nkusaolp00

Hi Barbara. Is one of the strongest sal events of recent years. The sky will turn very hazy and dry until it passes.