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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
927 AM EDT WED MAY 6 2015

.UPDATE...
LOW PRESSURE LOCATED JUST NW OF NW BAHAMAS...IN VICINITY OF OUR
NORTHERN OFFSHORE ATLANTIC WATERS. TRACK SHOULD TAKE THE FEATURE
NORTHWARD AND AWAY FROM THE REGION. NHC NOW GIVES THE SYSTEM 60
PERCENT CHANCE OF TROPICAL/SUBTROPICAL DEVELOPMENT BY FRIDAY.

MAIN CHALLENGE IN TODAYS FORECAST CONTINUES TO BE HOW MUCH IMPACT
THE DRY AIR WRAPPING AROUND THE SYSTEM FROM THE NORTHWEST WILL
HAVE ON SOUTH FLORIDA WEATHER. HAVE LOWERED POPS A BIT BASED ON
LATEST GUIDANCE. IF CONVECTION DOES FIRE...THE MOST LIKE SCENARIO
WILL BE DEVELOPMENT EARLY AFTERNOON ACROSS NE CWA...THEN SPREADING
SOUTH/SOUTHWESTWARD TO THE GULF COAST BY EARLY EVENING.

&&

.PREV DISCUSSION... /ISSUED 736 AM EDT WED MAY 6 2015/ 

AVIATION...

WITH THE LOSS OF HEATING OVER THE MORNING HOURS THE MAIN AREA OF 
PRECIPITATION IS FOCUSED OFF THE COAST OF PALM BEACH, WHERE THE
STRONGEST FORCING IS OCCURRING. THE CURRENT TAFS INCLUDE VCTS
CONDITIONS FOR PBI AND FLL AFTER 14Z. THIS IS A LOW CONFIDENCE
FORECAST BECAUSE ANY CHANGE IN THE TRACK AND INTENSITY OF THE LOW
PRESSURE, IN CONJUNCTION WITH CHANGES IN CLOUD COVER, COULD
GENERATE AN AFTERNOON SEA BREEZE FOR THE EAST COAST. IF THE EAST
COAST SEA BREEZE DEVELOPS, THERE IS ENOUGH COLD AIR ALOFT TO
TRIGGER A FEW STRONG THUNDERSTORMS. THE CURRENT REASONING IS THAT
AREAS SOUTH OF PBI AND FLL SHOULD MAINLY BE AFFECTED BY SHOWERS
DUE TO THE INFLUENCE OF DRIER AIR AND WESTERLY FLOW. AMENDMENTS WILL
BE ISSUED AS NEEDED.

PREV DISCUSSION... /ISSUED 444 AM EDT WED MAY 6 2015/ 

DISCUSSION...

THE LATEST REGIONAL OBSERVATIONS...WATER VAPOR SATELLITE IMAGERY
AND SUITE OF MODEL  GUIDANCE INDICATE THERE IS LIKELY A WEAK
SURFACE TROUGH JUST OFF THE COAST IN THE LOCAL ATLANTIC WATERS
WITH A BROAD SURFACE LOW IN THE VICINITY OF THE NORTHWEST
BAHAMAS. IN ADDITION THERE IS A LARGE AMPLITUDE UPPER LEVEL TROUGH
IN THE EASTERN GULF WITH SOUTH FLORIDA EAST OF THE TROUGH AXIS.
AND THERE IS DEEP TROPICAL MOISTURE ACROSS SOUTH FLORIDA AND
ADJACENT WATERS WITH WIDESPREAD SHOWERS ACROSS EASTERN PALM BEACH
COUNTY AND ADJACENT WATERS.

FOR TODAY...THE BROAD SURFACE LOW NEAR THE NORTHWEST BAHAMAS IS
FORECAST TO DRIFT NORTHWARD TODAY AND COULD BE EAST OF CENTRAL
FLORIDA LATER TODAY. MOST OF THE GUIDANCE INDICATES THAT AS IT
DRIFTS NORTHWARD THE MOISTURE CONVERGENCE WILL LIKELY SHIFT TO THE
EAST OF SOUTH FLORIDA WITH GRADUAL CLEARING AND DRYING. THIS COULD
ALLOW FOR DAY TIME HEATING TO ACTIVATE CONVECTION TODAY. IN
ADDITION THE MID LEVEL TEMPERATURES WILL CONTINUE TO BE AROUND 3
DEGREES COOLER THAN THE SEASONAL NORM AND FORECAST SOUNDINGS
INDICATE STEEPER LOW LEVEL LAPSE RATES. THE CONSENSUS OF THE
GUIDANCE DOES INDICATE CHANCES OF CONVECTION TODAY WITH THE MAIN
FOCUS ACROSS THE EASTERN HALF OF THE PENINSULA AND THE GREATEST
COVERAGE ACROSS PALM BEACH COUNTY AND THE ADJACENT ATLANTIC COAST
WATERS. THE FORECAST SOUNDINGS INDICATE A GRADUAL DRYING OF THE
MID TO UPPER LEVELS INTO THE AFTERNOON. WITH THE COMBINATION OF
THE COOLER MID LEVELS AND DRIER MID TO UPPER LEVELS...THIS MAY
ALLOW FOR AN ISOLATED STRONG THUNDERSTORM WITH THE POTENTIAL FOR
HAIL AND STRONG GUSTY WINDS. THE MOST LIKELY AREAS FOR ANY STRONG
THUNDERSTORMS WOULD BE ACROSS NORTHERN BROWARD COUNTY AND PALM
BEACH COUNTY AND ADJACENT WATERS.

THERE IS A MODERATE RISK OF RIP CURRENTS TODAY ALONG THE PALM
BEACH COUNTY BEACHES AND A SLIGHT RISK ALONG THE MIAMI DADE AND
BROWARD COUNTY BEACHES.

FOR THURSDAY AND FRIDAY...THE GENERAL GUIDANCE CONSENSUS INDICATES THE
SURFACE LOW WILL DRIFT NORTHWARD TONIGHT THROUGH THURSDAY WHILE
SLOWLY DEEPENING AND BECOMING MORE ORGANIZED. IT'S FORECAST TO BE
EAST OF THE GEORGIA COAST BY THURSDAY AFTERNOON. THE UPPER LEVEL
TROUGH WILL CONTINUE TO LINGER ACROSS THE FLORIDA PENINSULA. LOW
LEVEL SOUTHERLY FLOW WILL CONTINUE TO BRING AVAILABLE MOISTURE
INTO THE REGION WITH DIURNALLY DRIVEN SHOWERS/THUNDERSTORMS
FORECAST...BUT MAINLY SCATTERED ACTIVITY IN THE INTERIOR AS LIGHT
REGIONAL WINDS WILL ALLOW FOR THE EAST/WEST COAST SEA BREEZES TO
FORM WITH INTERIOR CONVECTION. FOR FRIDAY...WITH UPPER
LEVEL/SURFACE RIDGE FORECAST TO BUILD NORTH OF THE SURFACE LOW IT
IS FORECAST TO SLOWLY DRIFT TO THE NORTHWEST OFF THE CAROLINA
COAST. SIMILAR TO THURSDAY...AVAILABLE MOISTURE AND SEA BREEZE
CONVERGENCE WILL ALLOW FOR MAINLY INTERIOR AND EASTERN PENINSULA
SHOWERS/THUNDERSTORMS.

FOR THE UPCOMING WEEKEND...THE UPPER LEVEL LEVEL TROUGH IS
FORECAST TO SLOWLY DRIFT EASTWARD TOWARD THE BAHAMAS AS A LARGE
AMPLITUDE RIDGE BUILDS ACROSS THE EASTERN CONUS AND A WEAK HIGH
PRESSURE WILL EXTEND INTO SOUTH FLORIDA. ONLY ISOLATED TO
SCATTERED AFTERNOON SHOWERS/THUNDERSTORMS FORECAST MAINLY ACROSS
THE INTERIOR

MARINE...

WINDS AND SEAS WILL SLOWLY SUBSIDE ACROSS THE REGIONAL WATERS
TODAY. CHANCES OF SHOWERS AND THUNDERSTORMS ARE MAINLY EXPECTED
ACROSS THE ATLANTIC WATERS...WITH THE GREATEST COVERAGE EXPECTED
EAST OF PALM BEACH COUNTY. THERE IS SOME UNCERTAINTY IN THE WIND
FORECAST AS THE SURFACE LOW NEAR THE NORTHERN BAHAMAS CONTINUES
TO DRIFT NORTHWARD AND IS FORECAST TO SLOWLY DEEPEN. SEAS FROM 5
TO 7 FEET MAY BE POSSIBLE EARLY THURSDAY MORNING TO THE EAST OF
PALM BEACH COUNTY WITH A SMALL CRAFT ADVISORY POSSIBLE IF
CONDITIONS WARRANT.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  81  67  84  68 /  50  20  20  20 
FORT LAUDERDALE  84  71  84  72 /  40  20  30  20 
MIAMI            84  70  85  71 /  40  20  30  20 
NAPLES           85  69  86  69 /  20  10  20  10 

&&

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

$$

SHORT TERM...23/SK
LONG TERM....23/SK

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