Flash Flood Warning 30, NWS JSJ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
514 PM AST MON AUG 25 2008

.DISCUSSION...AT 5 PM AST...2100 UTC...THE CENTER OF RECENTLY
UPGRADED TROPICAL STORM GUSTAV WAS LOCATED NEAR LATITUDE 16.3
NORTH...LONGITUDE 71.0 WEST AND WAS MOVING NORTHWEST AT 12 KNOTS.
BASED ON THE LATEST TROPICAL CYCLONE ADVISORIES...GUSTAV IS
EXPECTED TO CONTINUE MOVING IN A GENERAL NORTHWEST DIRECTION AND
AWAY FROM THE LOCAL AREA OVER THE NEXT COUPLE OF DAYS...WITH A
GRADUAL DECREASE IN FORWARD SPEED. HOWEVER...THIS SYSTEM WILL
CONTINUE TO SPREAD DEEP TROPICAL MOISTURE AND INSTABILITY ACROSS
THE LOCAL AREA THROUGH AT LEAST WEDNESDAY...POSSIBLY LINGERING
THROUGH THURSDAY AND FRIDAY. THIS MOISTURE AND INSTABILITY WILL
COMBINE WITH LOCAL EFFECTS AND GENERALLY FAVORABLE UPPER LEVEL
WIND CONDITIONS THROUGH AT LEAST WEDNESDAY...TO PRODUCE VERY
UNSETTLED CONDITIONS WITH CLOUDINESS...SHOWERS AND THUNDERSTORMS
ACROSS THE LOCAL ISLANDS...ESPECIALLY DURING THE TIMES OF MAX
HEATING.

WE CONTINUE TO EXPECT PERIODS OF MODERATE TO HEAVY RAINFALL IN
ASSOCIATION WITH OUTER FRINGE BANDS OF GUSTAV...WHICH WILL
CONTINUE TO RESULT IN URBAN AND SMALL STREAM FLOODING ACROSS THE
LOCAL ISLANDS. HOWEVER...THE POTENTIAL STILL EXISTS FOR MORE
SIGNIFICANT RAINFALL TO DEVELOP WHICH COULD EVENTUALLY RESULT IN
AT LEAST SOME LOCALIZED FLASH AND RIVER FLOODING. ALL LOCAL
RESIDENTS AND VISITORS SHOULD CONTINUE TO CLOSELY MONITOR THE
WEATHER DURING THE NEXT SEVERAL DAYS.

&&

.AVIATION...OCCASIONAL BANDS OF SHOWERS AND EMBEDDED
THUNDERSTORMS WILL CONTINUE TO MOVE NORTH NORTHWEST ACROSS THE
LOCAL ISLANDS TONIGHT AND TUESDAY. OUTSIDE OF THESE BANDS...
EXPECT MOSTLY VFR WITH LOCAL MVFR CONDITIONS. HOWEVER...WITHIN
THESE BANDS EXPECT MVFR CONDITIONS WITH AREAS OF IFR
CONDITIONS...BRIEF STRONG AND GUSTY WINDS AND MOUNTAIN
OBSCURATIONS IN SHOWERS...THUNDERSTORMS AND SQUALLS.

&&

.MARINE...EXPECT WINDS OF 20 KNOTS OR LESS AND SEAS OF 5 FEET OR
LESS ACROSS THE REGIONAL WATERS THROUGH AT LEAST WEDNESDAY. THERE
IS A PRECAUTIONARY STATEMENT FOR ALL OF THE LOCAL ATLANTIC AND
CARIBBEAN COASTAL WATERS FOR TONIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU  77  88  76  89 /  50  50  40  50
STT  78  86  77  88 /  70  70  50  50

&&

.SJU WATCHES/WARNINGS/ADVISORIES...
PR...NONE.
VI...NONE.
&&

BCS

HAZARDOUS WEATHER OUTLOOK FOR PUERTO RICO AND THE U.S. VIRGIN
ISLANDS
NATIONAL WEATHER SERVICE SAN JUAN PR
617 AM AST MON AUG 25 2008

AMZ710>750-PRZ001>013-261030-
SAN JUAN AND VICINITY-NORTHEAST-SOUTHEAST-EASTERN INTERIOR-
NORTH CENTRAL-CENTRAL INTERIOR-PONCE AND VICINITY-NORTHWEST-
WESTERN INTERIOR-MAYAGUEZ AND VICINITY-SOUTHWEST-CULEBRA-VIEQUES-
THE NEARSHORE AND OFF SHORE ATLANTIC AND CARIBBEAN COASTAL WATERS-
617 AM AST MON AUG 25 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO AND THE
ADJACENT COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT
A BROAD AREA OF LOW PRESSURE MOVING SOUTH OF THE LOCAL AREA
THIS MORNING WILL CONTINUE TO SPREAD TROPICAL MOISTURE ACROSS THE
REGION THROUGHOUT THE DAY. BANDS OF MOISTURE WITH SHOWERS AND
ISOLATED THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE LOCAL
WATERS AND PROPAGATE NORTHWARDS ACROSS THE ISLANDS FROM TIME TO
TIME. THIS WILL RESULT IN PERIODS OF MODERATE TO LOCALLY HEAVY
RAINFALL ACROSS PARTS OF THE ISLANDS...THUS INCREASING THE
POTENTIAL FOR URBAN AND SMALL STREAM FLOODING IN SOME AREAS...
AS WELL AS DANGEROUS CLOUD TO GROUND LIGHTNING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY
ABUNDANT AMOUNTS OF TROPICAL MOISTURE IS FORECAST TO LINGER
ACROSS THE LOCAL AREA AT LEAST THROUGH FRIDAY. THIS WILL MAINTAIN
MODERATE TO HIGH CHANCES OF RAINFALL...AND CONSEQUENTLY THE
LIKELIHOOD OF URBAN AND SMALL STREAM FLOODING ESPECIALLY DURING THE
AFTERNOON HOURS. LOCAL AND DIURNAL EFFECTS WILL ALSO AID IN THE
DEVELOPMENT OF STRONG THUNDERSTORMS WHICH WILL INCREASE THE RISKS
OF DANGEROUS CLOUD TO GROUND LIGHTNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

AMZ720-730-VIZ001-002-261030-
ST. THOMAS ST. JOHN ADJACENT ISLANDS-ST CROIX-
NEARSHORE ATLANTIC AND ADJACENT CARIBBEAN COASTAL WATERS-
617 AM AST MON AUG 25 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE U.S. VIRGIN ISLANDS AND
THE ADJACENT COASTAL WATERS.

.DAY ONE...TODAY AND TONIGHT
A BROAD AREA OF LOW PRESSURE MOVING SOUTH OF THE LOCAL AREA
THIS MORNING WILL CONTINUE TO SPREAD TROPICAL MOISTURE ACROSS THE
REGION THROUGHOUT THE DAY. BANDS OF MOISTURE WITH SHOWERS AND
ISOLATED THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE LOCAL
WATERS AND PROPAGATE NORTHWARDS ACROSS THE ISLANDS FROM TIME TO
TIME. THIS WILL RESULT IN PERIODS OF MODERATE TO LOCALLY HEAVY
RAINFALL ACROSS PARTS OF THE ISLANDS...THUS INCREASING THE
POTENTIAL FOR URBAN AND SMALL STREAM FLOODING IN SOME AREAS...
AS WELL AS DANGEROUS CLOUD TO GROUND LIGHTNING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY
ABUNDANT AMOUNTS OF TROPICAL MOISTURE IS FORECAST TO LINGER
ACROSS THE LOCAL AREA AT LEAST THROUGH FRIDAY. THIS WILL MAINTAIN
MODERATE TO HIGH CHANCES OF RAINFALL...AND CONSEQUENTLY THE LIKELIHOOD
OF URBAN AND SMALL STREAM FLOODING ESPECIALLY DURING THE AFTERNOON
HOURS. LOCAL AND DIURNAL EFFECTS WILL ALSO AID IN THE DEVELOPMENT
OF STRONG THUNDERSTORMS WHICH WILL INCREASE THE RISKS OF DANGEROUS
CLOUD TO GROUND LIGHTNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.