EF0 tornado, Boca Raton, Florida, September 16, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
1021 AM EDT MON SEP 16 2013

.UPDATE...
SHOWERS AND THUNDERSTORMS HAVE BEEN QUITE NUMEROUS OVER MIAMI-
DADE...MAINLAND MONROE...AND ADJACENT WATERS THIS MORNING. RADAR
TRENDS SUGGEST ACTIVITY IS DEVELOPING NORTHWARD INTO BROWARD AND
PALM BEACH COUNTIES. EXPECT LIKELY COVERAGE THROUGHOUT TODAY AS
RICH TROPICAL MOISTURE...BROAD ASCENT...AND MODERATE INSTABILITY
COMBINE. NO CHANGES TO OVERALL FORECAST THINKING. POPS HAVE BEEN
ADJUSTED BASED ON PRESENT CONDITIONS AND MESOSCALE GUIDANCE.

&&

.PREV DISCUSSION... /ISSUED 739 AM EDT MON SEP 16 2013/

AVIATION...

SHOWERS AND STORMS WERE ONGOING NEAR/AT THE EAST COAST TAF SITES
THIS MORNING. SHOWERS AND STORMS WERE ALREADY BEGINNING TO FILL IN
OVER THE ATLANTIC WATERS IN AREAS THAT RECEIVED RAINFALL
OVERNIGHT. SO EXPECT NUMEROUS SHOWERS/STORMS TO AFFECT THE TAF
SITES THROUGHOUT THE DAY. TIMING OF ANY ONE STORM AFFECTING AN
INDIVIDUAL TAF SITE THROUGHOUT THE DAY IS DIFFICULT. MVFR/IFR
CONDITIONS ARE POSSIBLE IN SHOWERS/STORMS. EAST WINDS AROUND 10-12
KNOTS ARE FORECAST FOR TODAY AT THE TAF SITES...WITH WINDS
DIMINISHING OVERNIGHT. UPPER LEVEL VORTICITY WILL MOVE NORTH FROM
NEAR CUBA OVERNIGHT...AND THIS MAY GENERATE SHOWERS/STORMS ONCE
AGAIN FOR THE EAST COAST TAF SITES LATE IN THE NIGHT...ESPECIALLY
ACROSS THE SOUTH.

PREV DISCUSSION... /ISSUED 330 AM EDT MON SEP 16 2013/

DISCUSSION...A BROAD INVERTED LOW TO MID LEVEL INVERTED TROUGH
EXTENDS FROM THE WESTERN CARIBBEAN SEA NORTHEAST ACROSS SOUTH FL.
MOISTURE CONTINUES HIGH ACROSS THE AREA WITH GPS MET DATA SHOWING
PWAT VALUES OF AROUND 2.1 INCHES. FORECAST SOUNDINGS SHOW A
MOIST, AND UNSTABLE PROFILE THROUGH MID WEEK, WHICH WILL LEAD TO A
CONTINUATION OF WET AND STORMY CONDITIONS EACH DAY...ESPECIALLY
TODAY AND TUESDAY WITH THE BROAD LOW-MID LEVEL TROUGH STRETCHED
ACROSS THE AREA. GFS AND NAM MOS SHOW HIGH POPS TODAY AND TUESDAY
AND SEE NO REASON TO DEVIATE. CLOUD COVER WILL BE QUITE EXTENSIVE,
BUT WITH THE HIGH MOISTURE LEVELS IN PLACE AND CONVERGENCE FROM
THE BROAD TROUGH, SHOWERS AND TSTORMS ARE EXPECTED TO DEVELOP,
SPREADING FROM EAST TO WEST AS THEY DO SO. THE MAIN IMPACT FROM
THE THUNDERSTORMS WILL BE LOCALLY HEAVY RAINFALL AND LIGHTNING.

BY WEDNESDAY AND THROUGH LATE THIS WEEK, HIGH PRESSURE OVER THE
SOUTHEAST STATES NOSES IN AND A MID LEVEL TROUGH AMPLIFIES OVER THE
ATLANTIC. THIS WILL LEAD TO A DRYING NW WIND FLOW AT UPPER LEVELS.
MOISTURE WILL CONTINUE SUFFICIENT AT LOWER LEVELS TO CONTINUE A
CHANCE OF SHOWERS/TSTORMS EACH DAY THOUGH. MID LEVEL TEMPS DO
GRADUALLY WARM THROUGHOUT THE WEEK...AND WITH SOME DRYING WED AND
LATE WEEK, LESS ACTIVE WEATHER IS EXPECTED.

THE WEATHER PATTERN LOOKS INTERESTING ABOUT A WEEK FROM NOW AS
BOTH GFS AND ECMWF SHOW A BROAD LOW OR TROUGH DEVELOPING. PREVIOUS
MODEL RUNS TOOK A LOW NORTHEASTWARD NEAR OR ACROSS SOUTH FL AS A
LONGWAVE TROUGH AMPLIFIED IN THE MODELS ACROSS THE EASTERN SATES.
HOWEVER, THE LATEST RUNS OF BOTH THE GFS AND ECMWF DO NOT AMPLIFY
THE LONGWAVE TROUGH AS MUCH AND LEAVE LOW PRESSURE OR A BROAD
TROUGH HUNG UP ACROSS SOUTH FL FOR SEVERAL DAYS NEXT WEEK. IT IS
WAY TOO SOON TO HAVE ANY CONFIDENCE IN ONE SCENARIO, BUT IT'S
SOMETHING TO WATCH AS THIS PATTERN WOULD HAVE THE POTENTIAL TO
PRODUCE COPIOUS RAINFALL ACROSS SOUTH FLORIDA, WITH OR WITHOUT ANY
TROPICAL DEVELOPMENT.

AVIATION...FOR 06Z TAFS...
DEEP MOISTURE WILL REMAIN ACROSS SOUTH FLORIDA OVER THE NEXT
COUPLE DAYS. SHOWERS WERE BEGINNING TO REDEVELOP OVER THE ATLANTIC
WATERS TO THE EAST OF KMIA...AND THESE SHOWERS COULD MOVE TOWARDS
THE COAST OVER THE NEXT SEVERAL HOURS. KEPT WITH VCSH FOR
NOW...BUT IT IS POSSIBLE STORMS COULD DEVELOP NEAR THE TAF SITES
BEFORE 12Z. THE DEEP MOISTURE AND LIGHT TO MODERATE EASTERLY FLOW
COMBINED WITH A WEAK SURFACE TROUGH WILL LEAD TO NUMEROUS SHOWERS
AND STORMS ACROSS THE REGION ONCE AGAIN TODAY. SHOWERS AND STORMS
COULD OCCUR AT ANY TIME THROUGHOUT THE DAY...BUT THE MOST LIKELY
PERIOD MAY BE THE LATE MORNING AND EARLY AFTERNOON FOR THE EAST
COAST AND EARLY TO MID AFTERNOON FOR KAPF. SO ADDED TEMPO AND
PROB30 GROUPS TO ACCOUNT FOR THIS AND KEEP CONSISTENT WITH THE
HIGH POPS FORECAST. MVFR/IFR CONDITIONS ARE POSSIBLE IN/NEAR
SHOWERS AND STORMS. AN UPPER LEVEL VORTICITY MAX IS FORECAST TO
MOVE NORTHWARD TOWARDS THE REGION MONDAY NIGHT INTO TUESDAY
MORNING...AND THIS IS FORECAST TO ENHANCE SHOWERS AND STORMS FOR
AT LEAST THE EAST COAST TAF SITES NEAR OR AFTERNOON THE END OF THE
CURRENT TAF PERIOD.

MARINE...A MODERATE EASTERLY WIND FLOW WILL PREVAIL WITH SEAS OF
2-4 FT, EXCEPT LESS THAN 2 FT NEAR SHORE GULF WATERS. WINDS/SEAS
WILL BE HIGHER IN AND NEAR SHOWER AND THUNDERSTORMS.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH  77  89  76  90 / 50 70 40 50
FORT LAUDERDALE  80  89  77  90 / 50 70 40 50
MIAMI            77  89  78  89 / 50 70 40 50
NAPLES           75  91  76  92 / 50 70 40 50

&&

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

DISCUSSION/MARINE/FIRE...23/SK
AVIATION/RADAR...60/BD

HAZARDOUS WEATHER OUTLOOK FOR SOUTH FLORIDA
NATIONAL WEATHER SERVICE MIAMI FL
344 AM EDT MON SEP 16 2013

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
162245-
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-
344 AM EDT MON SEP 16 2013

...NUMEROUS THUNDERSTORMS WITH GUSTY WINDS AND LOCALLY HEAVY RAINFALL...
...MODERATE RISK OF RIP CURRENTS EAST COAST BEACHES...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH FLORIDA.

.DAY ONE...TODAY AND TONIGHT

RIP CURRENTS: EAST WINDS OF 10 TO 15 MPH WILL LEAD TO A MODERATE
RISK OF RIP CURRENTS ALONG THE ATLANTIC BEACHES.

THUNDERSTORMS: NUMEROUS THUNDERSTORMS ARE FORECAST ACROSS THE
REGION TODAY. THE PRIMARY IMPACTS FROM THE STORMS WILL BE FREQUENT
LIGHTNING STRIKES, GUSTY WINDS UP TO 50 MPH, AND LOCALLY HEAVY
RAINFALL.

WIND: THE STRONGEST STORMS WILL BE CAPABLE OF PRODUCING WIND
GUSTS TO 50 MPH.

FLOODING: LOCALLY HEAVY RAINFALL MAY LEAD TO PONDING ON ROADWAYS
AND MINOR FLOODING OF LOW LYING URBAN AND POORLY DRAINED AREAS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

SCATTERED TO NUMEROUS THUNDERSTORMS WILL CONTINUE THROUGHOUT THE
UPCOMING WEEK, WITH THE HIGHEST CHANCES FOR STORMS ON TUESDAY.
THE MAIN THREATS WILL BE OCCASIONAL TO FREQUENT LIGHTNING STRIKES
AND LOCALLY HEAVY RAINFALL WHICH MAY LEAD TO MINOR FLOODING.

THE RIP CURRENT RISK WILL CONTINUE ALONG THE ATLANTIC BEACHES THROUGH
MID-WEEK AS EAST WINDS CONTINUE ACROSS THE AREA.

.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.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
1013 AM EDT MON SEP 16 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0835 AM     MARINE TSTM WIND 8 SSE KEY BISCAYNE      25.59N  80.10W
09/16/2013  M44 MPH          AMZ651             FL   BUOY

            A THUNDERSTORM PEAK WIND GUST OF 38 KNOTS WAS REPORTED
            AT BUOY FWYF1

&&

EVENT NUMBER MFL1300203

BCD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
1047 AM EDT MON SEP 16 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     WATER SPOUT      2 ESE TEQUESTA          26.95N  80.06W
09/15/2013                   AMZ650             FL   BROADCAST MEDIA

            VIDEO DEPICTS WATERSPOUT OFFSHORE JUPITER BEACH.

&&

EVENT NUMBER MFL1300204

KONARIK