Special Weather Statement, NWS Miami, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
200 PM EDT SUN AUG 4 2013

.SHORT TERM (TONIGHT-TUESDAY NIGHT)...
A LARGE SCALE MID LEVEL TROUGH WILL ACROSS THE EASTERN SEABOARD AND
INTO THE ATLANTIC THROUGH MONDAY WITH A STRONG RIDGE AXIS EXTENDING
FROM TEXAS TO THE FLORIDA STRAITS. THIS PATTERN WILL ALSO MAINTAIN A
SURFACE HIGH PRESSURE RIDGE OVER THE FLORIDA STRAITS. FORECAST
SOUNDINGS ALSO CONTINUE TO INDICATE PWAT WILL REMAIN AT AROUND TWO
INCHES WITH A WNW STEERING FLOW SO THE HIGHEST CHANCES FOR
CONVECTIVE DEVELOPMENT FOR THIS AFTERNOON AND AGAIN ON MONDAY
AFTERNOON WILL CONTINUE TO BE OVER THE INTERIOR AND EAST COAST METRO
AREAS. THIS IS REFLECTED WELL IN THE CURRENT FORECAST SO NO CHANGES
ARE FORESEEN AT THIS TIME. STABILITY WILL ALSO REMAIN UNCHANGED WITH
THE LOWEST LEVELS VERY UNSTABLE AND ONLY MARGINAL MID LEVEL LAPSE
RATES SO THE PRIMARY CONCERN WILL BE LOCALLY HEAVY RAINFALL AND
ISOLATED STRONG WIND GUSTS ALONG WITH THE POSSIBLE FREQUENT
LIGHTNING STRIKES.

TUESDAY IS CONTINUING TO LOOK LIKE A TRANSITIONAL DAY WITH THE
TROUGH LIFTING TO THE EAST WHICH WILL ALLOW FOR A DEEP LAYER RIDGE
TO BEGIN DEVELOPING ACROSS THE FLORIDA PENINSULA. THIS RIDGE WILL
FIRST SET UP ACROSS SOUTH FLORIDA SO SEA BREEZE INTERACTIONS WILL
LIKELY PLAY THE MAJOR FOCUS ON TUESDAY AFTERNOON WITH FORECAST
SOUNDINGS SHOWING AN AVERAGE STORM MOTION OF LESS THAN 5 MPH. SO
SLOW AND ERRATIC MOVEMENT APPEARS LIKELY WITH EQUAL CHANCES JUST
ABOUT ANYWHERE. THE PWAT WILL ALSO CONTINUE AT AROUND TWO INCHES SO
THE HEAVIER RAIN THREAT COULD ACTUALLY BE A LITTLE HIGHER WITH THE
SLOWER STORM MOTIONS EXPECTED. IN ADDITION, MID LEVEL LAPSE RATES
ARE EXPECTED TO REMAIN MARGINAL SO THE ONLY OTHER THREAT WILL BE
ISOLATED STRONG WIND GUSTS.

.LONG TERM (WEDNESDAY-SUNDAY)...
GLOBAL MODELS AGREE THAT THE DEEP LAYER RIDGE WILL SHIFT TO NORTH
FLORIDA BY WEDNESDAY ALONG WITH A MID LEVEL INVERTED TROUGH MOVING
WEST ACROSS THE BAHAMAS. THIS WILL PLACE SOUTH FLORIDA ON THE
SUBSIDENCE SIDE OF THIS TROUGH AND THE RAIN CHANCES COULD GO DOWN
ALONG WITH A DEEP EASTERLY FLOW SETTING UP. BOTH THE GFS AND ECMWF
DEPICT THIS TROUGH MOVING ACROSS SOUTH FLORIDA ON FRIDAY AND INTO
THE GULF OF MEXICO ON SATURDAY. THIS COULD INCREASE THE RAIN CHANCES
AGAIN WITH INCREASED LAPSE RATES AS THE MID LEVELS COOL ALONG WITH A
TRANSPORT OF TROPICAL MOISTURE NORTHWARD FROM THE CARIBBEAN.

&&

.AVIATION...
THE EAST COAST SEA BREEZE HAS BEGUN TO PENETRATE JUST INLAND FROM
THE COAST THIS AFTERNOON...WHICH SHOULD ENHANCE THE LOW-LEVEL
CONVERGENCE WITH THE LIGHT WESTERLY LOW-LEVEL FLOW IN PLACE. WILL
INCLUDE VCTS IN THE EAST COAST TAF SITES FROM 20Z ON TODAY. THE
LATEST HI-RES MODEL GUIDANCE CONTINUES TO INDICATE WIDESPREAD
ACTIVITY DEVELOPING THROUGH THE LATE AFTERNOON AND EVENING HOURS
FAVORING THE EASTERN HALF OF THE SRN FL PENINSULA TODAY. SUB IFR
CONDITIONS MAY RESULT FOR PERIODS OF TIME IF THIS ACTIVITY SETS UP
OVER THE TERMINALS. WILL INDICATE THINGS TRENDING DOWN BEYOND 02Z
WITH ANOTHER QUIET OVERNIGHT EXPECTED. SIMILAR CONDITIONS WILL BE
EXPECTED MONDAY WITH THE LIGHT WESTERLY FLOW IN PLACE.

&&

.MARINE...
TRANQUIL WIND AND SEAS WILL CONTINUE THROUGH EARLY THIS WEEK WITH
A LIGHT WIND FLOW LESS THAN 10 KNOTS. AN EAST WIND WILL RETURN BY
MID WEEK BUT AT SPEEDS OF LESS THAN 15 KNOTS SO OVERALL SEAS ARE
EXPECTED TO REMAIN BELOW 4 FEET BUT COULD BE HIGHER NEAR SCATTERED
SHOWERS AND THUNDERSTORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  78  92  78  91 / 20 50 20 40
FORT LAUDERDALE  77  91  78  88 / 30 50 20 40
MIAMI            78  91  78  91 / 30 50 20 40
NAPLES           77  91  77  90 / 10 40 20 40

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&

DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...85/AG

HAZARDOUS WEATHER OUTLOOK FOR SOUTH FLORIDA
NATIONAL WEATHER SERVICE MIAMI FL
407 AM EDT SUN AUG 4 2013

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
050400-
LAKE OKEECHOBEE-BISCAYNE BAY-
COASTAL WATERS FROM JUPITER INLET TO DEERFIELD BEACH, FL OUT 20 NM-
COASTAL WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL OUT 20 NM-
WATERS FROM JUPITER INLET TO DEERFIELD BEACH, FL EXTENDING FROM
20 NM TO 60 NM-
WATERS FROM DEERFIELD BEACH TO OCEAN REEF, FL EXTENDING FROM 20 NM
TO THE TERRITORIAL WATERS OF THE BAHAMAS-GLADES-HENDRY-
INLAND PALM BEACH-METRO PALM BEACH-COASTAL COLLIER-INLAND COLLIER-
INLAND BROWARD-METRO BROWARD-INLAND MIAMI DADE-METRO MIAMI DADE-
MAINLAND MONROE-COASTAL PALM BEACH-COASTAL BROWARD-
COASTAL MIAMI DADE-FAR SOUTH MIAMI DADE-
COASTAL WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL OUT 20 NM-
COASTAL WATERS FROM EAST CAPE SABLE TO CHOKOLOSKEE, FL OUT 20 NM-
GULF WATERS FROM CHOKOLOSKEE TO BONITA BEACH, FL EXTENDING FROM
20 TO 60 NM-
407 AM EDT SUN AUG 4 2013

...SCATTERED THUNDERSTORMS, FOCUSED INTERIOR AND EAST THIS AFTERNOON...
...A FEW STORMS COULD CONTAIN FREQUENT LIGHTNING AND GUSTY WINDS...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH FLORIDA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS: SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP
TODAY, BECOMING FOCUSED OVER THE INTERIOR AND EAST COAST LATE THIS
AFTERNOON. A FEW THUNDERSTORMS COULD CONTAIN FREQUENT LIGHTNING,
GUSTY WINDS AND HEAVY RAINS.

WIND: GUSTY WINDS OF 40 TO 50 MPH WILL BE POSSIBLE IN THE STRONGER
THUNDERSTORMS THIS AFTERNOON ACROSS THE INTERIOR AND EAST COAST.

TEMPERATURES: MAXIMUM HEAT INDICES WILL REACH NEAR 100 TODAY.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

SCATTERED MAINLY AFTERNOON THUNDERSTORMS ARE EXPECTED EACH
DAY...MOST FOCUSED OVER THE INTERIOR.

.SPOTTER INFORMATION STATEMENT...

WIDESPREAD SPOTTER ACTIVATION IS NOT ANTICIPATED, HOWEVER
INDIVIDUAL SPOTTERS ARE ENCOURAGED TO REPORT HIGH WIND, HAIL AND
FLOODING TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
MIAMI.

FOR MORE INFORMATION...VISIT THE NATIONAL WEATHER SERVICE IN
MIAMI WEBSITE AT WWW.WEATHER.GOV/MIAMI.

GREGORIA

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
355 PM EDT SUN AUG 4 2013

FLZ063-066-067-042045-
GLADES FL HENDRY FL INLAND PALM BEACH COUNTY FL
355 PM EDT SUN AUG 4 2013

...A SIGNIFICANT WEATHER ADVISORY IS IN EFFECT FOR WESTERN PALM BEACH
COUNTY...SOUTHEASTERN GLADES COUNTY...NORTHEASTERN HENDRY COUNTY...
FOR FREQUENT TO EXCESSIVE LIGHTNING AND GUSTY WINDS OF 45 TO 55
MPH...

* UNTIL 445 PM EDT

* AT 351 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  STRONG THUNDERSTORM NEAR CLEWISTON...AND MOVING SOUTHEAST AT 20
  MPH.

* THE STORM WILL AFFECT...
  HARLEM...
  LAKE HARBOR...
  SOUTH BAY...
  OKEELANTA...
  AND SURROUNDING COMMUNITIES.

THE PRIMARY IMPACTS WILL BE FREQUENT TO EXCESSIVE LIGHTNING AND GUSTY
WINDS OF 45 TO 55 MPH. LIGHTNING IS THE NUMBER ONE WEATHER RELATED
KILLER IN FLORIDA. TREES AND OPEN SHELTERS OFFER NO PROTECTION. THESE
WINDS CAN DOWN SMALL TREE LIMBS AND BRANCHES...AND BLOW AROUND
UNSECURED SMALL OBJECTS. SEEK SHELTER IN A SAFE BUILDING UNTIL THE
STORM PASSES.

LAT...LON 2682 8095 2680 8095 2677 8094 2674 8085
      2671 8081 2671 8078 2669 8074 2672 8073
      2675 8074 2669 8063 2651 8076 2670 8107
      2682 8099
TIME...MOT...LOC 1955Z 301DEG 16KT 2673 8093

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