Excessive Heat in Florida, September 8, 2011

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MIAMI FL
946 AM EDT THU SEP 8 2011

...LOCALLY HEAVY RAINFALL POSSIBLE LAKE OKEECHOBEE AREA AND PALM
BEACH COUNTY TODAY...

.UPDATE...
A STATIONARY FRONT WILL REMAIN OVER CENTRAL FLORIDA TODAY ALLOWING
FOR A SOUTHWEST STEERING FLOW OVER THE CWA. THIS WILL KEEP THE
EAST COAST SEA BREEZE OVER THE METRO AREAS THIS AFTERNOON AND
KEEPING THE TROPICAL MOISTURE IN PLACE. SO WILL CONTINUE WITH THE
SCATTERED POPS OVER THE SOUTHERN AREAS OF SOUTH FLORIDA INCREASING
TO NUMEROUS POPS OVER THE NORTHERN AREAS OF SOUTH FLORIDA FOR TODAY.

THE PWAT VALUES FROM THE MIA SOUNDING THIS MORNING WAS SHOWING
AROUND 2 INCHES...AND MLB SOUNDING THIS MORNING WAS SHOWING AROUND
2.2. MLB SOUNDING IS RUNNING NEAR 2 STANDARD DEVIATIONS ABOVE THE
1.9 CLIMO PWAT VALUES FOR THIS TIME OF YEAR, WHILE MIA SOUNDING IS
NEAR THE CLIMO PWAT VALUES. SO WILL ADD LOCALLY HEAVY RAINFALL TO
THE ZONES FOR THE NORTHERN AREAS OF THE CWA...AS THEY ARE CLOSER
TO THE 2 STANDARD DEVIATIONS ABOVE NORMAL.

THE SOUTHWEST WIND FLOW OVER THE CWA TODAY WILL ALSO ALLOW FOR
TEMPERATURES TO WARM UP INTO THE LOWER OT MID 90S. SO HAVE
INCREASE THE HIGHS OVER THE EAST COAST METRO AREAS A LITTLE BIT
FOR THIS AFTERNOON.

REST OF THE FORECAST LOOKS GOOD AT THIS TIME AND NO OTHER CHANGES
ARE PLAN.

&&
.UPDATE...54/BNB

.PREV DISCUSSION... /ISSUED 711 AM EDT THU SEP 8 2011/

AVIATION...A STATIONARY FRONTAL BOUNDARY REMAINS OVER CENTRAL
FLORIDA...WITH DEEPER LAYER TROPICAL MOISTURE REMAINING ACROSS
THE AREA. WEAK SOUTHWESTERLY FLOW STILL FORECAST TO BECOME MORE
MODERATE SOUTHWESTERLY FLOW BETWEEN 12Z AND 18Z...BUT A WEAK EAST
COAST SEA BREEZE FOR SITES KFLL...KFXE AND KMIA MAY BE POSSIBLE.
SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS EXPECTED BY EARLY
AFTERNOON WITH MORE NUMEROUS ACTIVITY FOR SITES KAPF AND KPBI AND
SCATTERED ACTIVITY EXPECTED AT THE REMAINING SITES. ALL TAF SITES
ASSIGNED VCTS AROUND 17Z. PERIODS OF MVFR/IFR POSSIBLE STARTING
EARLY AFTERNOON WITH OCCURRENCE OF SHOWERS/THUNDERSTORMS.

&&

PREV DISCUSSION... /ISSUED 335 AM EDT THU SEP 8 2011/

DISCUSSION...THE PAST FEW DAYS HAVE SEEN MORE CONVECTION THAN
I'VE FORECASTED AND INDICATIONS ARE THAT TODAY MAY BE ANOTHER
ACTIVE ONE. THE MAIN FACTORS POINTING TO THIS ARE HIGH
MOISTURE...PWAT NEAR 2 INCHES...AND CONVERGENCE ASSOCIATED ON THE
NORTHERN PERIPHERY OF THE SLOWLY NORTHWARD BUILDING LOW LEVEL
RIDGE AXIS WHICH HAS BEEN TO OUR SOUTH FOR THE PAST SEVERAL DAYS.
GUIDANCE SHOWS LOW LEVEL WINDS ON THE INCREASE OUT OF THE
SW...LIKELY INHIBITING AN EAST COAST SEA BREEZE. HOWEVER...OVERALL
BROAD/SYNOPTIC LOW LEVEL CONVERGENCE ALONG WITH SOME SLIGHT UPPER
DIVERGENCE...LOOKS TO ALLOW NUMEROUS THUNDERSTORMS TO DEVELOP FROM
NAPLES TO THE PALM BEACHES...AND PERHAPS A BIT LESS ACTIVITY
POINTS SOUTH AS SOME DRIER AIR TRIES TO MOVE IN FROM THE SOUTH
DURING THE DAY. GIVEN THIS...HAVE INCREASED POPS TO LIKELY ACROSS
THE NORTH HALF OF THE AREA AND HIGH CHANCE CATEGORY SOUTH HALF.

THE SURFACE/LOW LEVEL RIDGE AXIS BUILDS NORTH ACROSS THE AREA ON
FRIDAY THEN INTO CENTRAL FL FOR THE WEEKEND. THIS WILL ALLOW FOR
A SOUTHEASTERLY FLOW TO GRADUALLY DEVELOP...WITH CONVECTION
CONCENTRATING ACROSS THE INTERIOR TOWARDS THE GULF COAST. EARLY-
MIDDLE PART OF NEXT WEEK SHOWS ANOTHER SHORTWAVE TROUGH MOVING
ACROSS THE EASTERN SEABOARD...AND THIS LOOKS TO KEEP MARIA TO OUR
EAST AT THIS TIME. NATE IS FORECAST TO MOVE TOWARDS MEXICO. AND
KATIA OUT TO SEA AS WELL. GFS/ECMWF NOW IN LINE WITH ALL OF THIS.
SO ALTHOUGH THE TROPICS ARE VERY ACTIVE RIGHT NOW...SO FAR SO
GOOD HERE. THINGS CAN CHANGE SO IT'S ALWAYS GOOD TO MONITOR THE
LATEST FORECASTS.

NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST FOR THE WEEKEND
AND BEYOND...AS CONVECTION LOOKS TO CONCENTRATE INTERIOR...EXCEPT
ANYWHERE ON SUNDAY ON THE NORTHERN EXTENT OF A TROPICAL WAVE.
TEMPS WILL BE NEAR CLIMO.

MARINE...JUPITER AND BOCA CAM IMAGES FROM YESTERDAY EVENING
SHOWED FLAT SEAS AND NO SWELL PRESENT (AND NIGHT CAM AT JUPITER
CONTINUES TO LOOK FLAT)...WHILE THE SENSOR UP AT FORT PIERCE IS
REPORTING A 4.9 FT SWELL AT 15 SEC. SWAN SHOWS 1-3 FT SWELL
TODAY BEFORE DIMINISHING. WINDS/SEAS WILL REMAIN RATHER LOW
THROUGH THE FORECAST PERIOD...BUT COULD INCREASE TO AT OR SLIGHTLY
ABOVE 15 KT BEHIND THE NORTHERN AXIS OF A TROPICAL WAVE SUN-MON.

FIRE WEATHER...NO CONCERNS.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  92  74  89  77 / 60 40 40 20
FORT LAUDERDALE  91  77  90  80 / 50 30 30 20
MIAMI            92  77  91  78 / 50 30 30 20
NAPLES           89  75  91  76 / 50 30 40 20

&&

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

DISCUSSION/MARINE...57/DG
AVIATION/RADAR/FIRE...60/BD

HAZARDOUS WEATHER OUTLOOK FOR SOUTH FLORIDA
NATIONAL WEATHER SERVICE MIAMI FL
428 AM EDT THU SEP 8 2011

FLZ063-066>075-168-172>174-082330-
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-
428 AM EDT THU SEP 8 2011

...SCATTERED TO NUMEROUS THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH FLORIDA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS: SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED
THIS AFTERNOON AND EARLY EVENING, WITH THE MORE NUMEROUS ACTIVITY
EXPECTED ACROSS THE NORTHERN PORTIONS OF THE LOCAL GULF WATERS AND
THE NORTHERN PORTIONS OF THE PENINSULA. THE PRIMARY THREATS WILL
BE FREQUENT LIGHTNING STRIKES, GUSTY WINDS, AND LOCALLY HEAVY
RAINFALL.

WIND: ANY THUNDERSTORMS THAT OCCUR ACROSS THE REGION TODAY MAY
CONTAIN GUSTY WINDS NEAR 45 TO 55 MPH.

FLOODING: SOUTHWESTERLY WINDS ACROSS THE REGION TODAY WILL LEAD TO
SHOWERS TRAINING ACROSS THE SAME AREAS WITH A SLIGHT RISK OF LOW
LYING AND POOR DRAINAGE AREAS EXPERIENCING URBAN TYPE FLOODING.

RIP CURRENTS: A MODERATE SOUTHWESTERLY FLOW WILL RESULT IN A SLIGHT RISK
OF RIP CURRENTS ALONG THE GULF COAST BEACHES OF COLLIER COUNTY
TODAY. A SMALL NORTHEAST SWELL WILL CONTINUE ACROSS THE ATLANTIC WATERS
TO THE EAST OF PALM BEACH COUNTY TODAY, RESULTING IN A SLIGHT RISK
OF RIP CURRENTS FOR THE ATLANTIC COAST BEACHES OF PALM BEACH
COUNTY.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SCATTERED THUNDERSTORMS ARE EXPECTED THROUGH THE PERIOD, WITH THE
BEST CHANCE DURING AFTERNOON AND EVENING HOURS. THE PRIMARY
IMPACTS WILL BE LIGHTNING STRIKES, GUSTY WINDS, AND LOCALLY HEAVY
RAINFALL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION: 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.