Severe Thunderstorm Warning 100, NWS Melbourne, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
156 PM EDT SAT AUG 21 2004

.DISCUSSION...

THROUGH TONIGHT...RADAR STARTING TO GET ACTIVE PRESENTLY WITH SEA
BREEZE ACTIVITY STARTING TO FIRE AND LINE OF STORMS GETTING BETTER
ORGANIZED TO THE NORTHWEST OF CWA. COVERAGE AND INTENSITY EXPECTED
TO INCREASE THROUGH THE LATE AFTERNOON...AND PERSIST INTO THE EARLY
EVENING HOURS AS NUMEROUS BOUNDARIES COLLIDE. CONDITIONS ALOFT
FAVORABLE FOR STRENGTHENING STORMS AND SOME SEVERE STORMS POSSIBLE
WITH COOL/DRY MID LEVELS...AN UPPER JET STREAK AND SOME VORT ENERGY.
12Z GFS DEPICTED VORT FIELD LOOKS MORE REASONABLE TODAY AND HAS SOME
AFFIRMATION FROM WATER VAPOR IMAGERY. THIS FEATURE WILL TRAVERSE THE
PENINSULA OVERNIGHT AND MAY KEEP STORMS GOING A WHILE PAST SUNSET...
ESPECIALLY SOUTHERN COASTAL SECTIONS. HAVE BUMPED EVENING POPS UP
SLIGHTLY INTO SCT CAT ALL AREAS WHICH MAY REQUIRE SOME FINAL TUNING
BE EVENING SHIFT.

ON SUN...THE SFC RIDGE AXIS WILL BE SUPPRESSED SOUTHWARD TWD LAKE
OKEECHOBEE AS FRONTAL BOUNDARY BECOMES STATIONARY ACROSS CENTRAL GA.
12Z ETA AND GFS INDICATE DEEP MOISTURE ACROSS NRN/CENTRAL SECTIONS
OF THE PENINSULA WITH PWATS FROM 1.9 - 2.1 INCHES. LOW LVL FLOW
SHOULD NOT BE STRONG ENOUGH TO HOLD OFF THE EAST COAST SEA BRZ
ACROSS THE CSTL COUNTIES...AND ALSO EXPECT WEST COAST ACTIVITY TO
TRACK EASTWARD ACROSS NRN SECTIONS. WILL KEEP POPS IN THE LIKELY
RANGE WITH 70 PCT NRN SECTIONS AND 60 PCT SOUTH. H5 TEMPS WARM TO -6
TO -7 WITH TUTT ACROSS THE BAHAMAS AND NNE FLOW ALOFT BUT DO NOT
THINK THIS FEATURE WILL HINDER AFTERNOON COVERAGE THAT MUCH.

MON/TUE...FAIRLY SIMILAR CONVECTIVE REGIME EXPECTED FOR THE
BEGINNING OF THE WORK WEEK WITH RIDGE AXIS NEAR LAKE OKEECHOBEE AND
PRE-FRONTAL BAND OF DEEP MOISTURE PARKED ACROSS THE CENTRAL
PENINSULA. GFS SHOWS PWATS REMAINING IN THE 2.0 - 2.2 INCH RANGE
WITH STEERING FLOW FROM THE WEST ACROSS NRN SECTIONS AND LIGHTER
STEERING FLOW ACROSS SRN SECTIONS. GFS ALSO INDICATES A SERIES OF
SHORTWAVES WILL TRACK ACROSS THE GULF COAST STATES INTO GA AND OFF
THE CAROLINA COAST. A FEW OF THESE IMPULSES SHOULD ENHANCE RAIN
CHANCES ACROSS THE NRN PENINSULA EARLY IN THE WEEK. WITH DEEP
MOISTURE WILL KEEP POPS IN THE LIKELY RANGE MON AND LIKELY FOR THE
NRN 2/3 OF THE AREA ON TUE.

WED LOOKS TO BE THE TRANSITION DAY AS THE RIDGE AXIS LIFTS NORTH AND
DEEPER SOUTHEASTERLY FLOW ENVELOPES SRN SECTIONS. WILL DROP POPS IN
TO THE SCATTERED RANGE.

THU-SAT...ATLC RIDGE REBUILDS NE OF THE AREA WITH LOW LEVEL FLOW
BACKING FROM SE TO EASTERLY BY THE WEEKEND. DECREASING DEEP LAYER
MOISTURE AND DEVELOPING SE/E FLOW WILL TREND POPS TO LOW SCATTERED
RANGE ALONG THE COAST AND SCATTERED FOR THE INTERIOR AS THE EAST
COAST SEA BREEZE MOVES INLAND EACH AFTERNOON.

&&

.MARINE...S/SW FLOW WILL CONTINUE THROUGH EARLY IN THE WEEK EXCEPT
FOR AN AFTERNOON SEA BRZ NEAR THE COAST EACH AFTERNOON. BOATERS WILL
HAVE TO BE ON THE LOOK OUT FOR AFTN STORMS MOVING TWD THE EAST COAST
SUNDAY THROUGH TUESDAY.  BY LATE WED AND THU...FLOW WILL TRANSITION
TO EAST TO SOUTHEAST AS ATLC RIDGE REBUILDS. WINDS MAINLY AROUND 10
KNOTS OR LESS.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  75  88  74  88 /  40  70  40  60
MCO  75  90  75  90 /  40  70  40  60
MLB  75  89  74  88 /  30  60  30  60
VRB  75  89  73  89 /  30  60  30  60

&&

.MLB WATCHES/WARNINGS/ADVISORIES...NONE.

&&

SHORT TERM...GLITTO
LONG TERM...VOLKMER

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MELBOURNE FL
1030 AM EDT SAT AUG 21 2004

AMZ550-555-570-575-FLZ041-044>047-053-054-058-059-064-141-144-147-
212100-
COASTAL VOLUSIA-COCOA BEACH TO JUPITER INLET 20 NM TO 60 NM OFFSHORE-
COCOA BEACH TO JUPITER INLET OUT TO 20 NM-
FLAGLER BEACH TO COCOA BEACH 20 NM TO 60 NM OFFSHORE-
FLAGLER BEACH TO COCOA BEACH OUT TO 20 NM-INDIAN RIVER-
INLAND VOLUSIA-MARTIN-NORTHERN BREVARD-NORTHERN LAKE-OKEECHOBEE-
ORANGE-OSCEOLA-SEMINOLE-SOUTHERN BREVARD-SOUTHERN LAKE-ST. LUCIE-
1030 AM EDT SAT AUG 21 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL FLORIDA.

.DAY ONE...

...THUNDERSTORM IMPACT...

...A LITTLE GREATER COVERAGE AND INTENSITY OF LIGHTNING STORMS
EXPECTED THIS AFTERNOON AND EVENING...

...MARINERS FROM THE CAPE NORTHWARD SHOULD BE ON THE LOOKOUT FOR
STORMS APPROACHING FROM THE WEST LATE THIS AFTERNOON AND EVENING...

THE AIR MASS OVER EAST CENTRAL FLORIDA HAS BECOME A LITTLE MORE
CONDUCIVE TO PRODUCING LIGHTNING STORMS THIS AFTERNOON. INCREASING
MOISTURE AND INSTABILITY COUPLED WITH A LITTLE MORE LARGE SCALE
LIFT...WILL RESULT IN SCATTERED TO NUMEROUS LIGHTNING STORMS TODAY.
THE HIGHEST COVERAGE IS EXPECTED TO BE FROM AROUND METRO ORLANDO AND
CAPE CANAVERAL NORTHWARD. FROM BREVARD AND OSCEOLA COUNTIES
NORTHWARD ...STORM MOTION WILL BE TOWARD THE EAST AT 10 TO 15 MPH...
WITH A SLOWER EASTWARD DRIFT OF AROUND 5 MPH...OVER OKEECHOBEE AND
THE TREASURE COAST COUNTIES.

LIGHTNING WILL BE THE GREATEST THREAT TODAY. ALSO...COOL AND DRY
CONDITIONS IN MID LEVELS OF THE ATMOSPHERE WILL BRING THE POTENTIAL
FOR A FEW STORMS TO PRODUCE DAMAGING WIND GUSTS IN EXCESS OF 55
MPH...HAIL UP TO THE SIZE OF A QUARTER...AND PERHAPS A BRIEF TORNADO
ALONG LOCAL BOUNDARY INTERACTIONS. PERSONS SHOULD MOVE INDOORS AT THE
FIRST SIGN OF THREATENING SKIES...STAY AWAY FROM WINDOWS AND REFRAIN
FROM USING THE PHONE OR ELECTRICAL APPLIANCES.

...FLOOD IMPACT...
SOME LOCATIONS COULD RECEIVE LOCALLY HEAVY RAINFALL BETWEEN TWO AND
FOUR INCHES IN A ONE OR TWO HOUR PERIOD...ESPECIALLY IN THE VICINITY
OF BOUNDARY COLLISIONS. THIS WOULD CAUSE TEMPORARY FLOODING IN POORLY
DRAINED AND URBAN AREAS. DO NOT USE CRUISE CONTROL WHEN DRIVING IN
RAIN. IT IS EASY TO LOSE CONTROL OF YOUR VEHICLE AND HYDROPLANE ON
RAIN SOAKED ROADS.

...MARINE THUNDERSTORM GUST IMPACT...
DUE TO AN INCREASING WEST TO EAST STEERING WIND NORTH OF CAPE
CANAVERAL...THERE IS A MUCH GREATER LIKELIHOOD FOR STORMS TO
PRODUCE WIND GUSTS OF 35 KNOTS OR GREATER...ROUGH SEAS...AND DEADLY
LIGHTNING TODAY. MARINERS ARE URGED TO KEEP THIS IN MIND IF YOU WILL
BE OUT ON THE INTRACOASTAL OR NEAR SHORE ATLANTIC WATERS. PREPARE
FOR THE POSSIBILITY OF STRONG STORMS MOVING IN RAPIDLY FROM THE WEST.
KEEP A WEATHER RADIO ON BOARD AND MOVE TO SAFE HARBOR QUICKLY AT THE
FIRST SIGN OF THREATENING WEATHER.

...WATERSPOUT IMPACT...
THERE IS ALSO THE THREAT FOR ISOLATED WATERSPOUTS OVER THE ATLANTIC
TODAY AS COVERAGE OF SHOWERS AND STORMS WILL BE HIGHER COMPARED TO
THE LAST FEW DAYS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY...
SCATTERED AFTERNOON AND EVENING LIGHTNING STORMS ARE EXPECTED EACH
DAY. STRONGER STORMS WITH LIGHTNING...GUSTY WINDS AND HEAVY RAIN
WILL BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE REQUESTED TO MONITOR THE WEATHER AND SELF ACTIVATE IF
NEEDED.

GLITTO

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MELBOURNE FL
158 PM EDT SAT AUG 21 2004

FLZ041-141-211900-
COASTAL VOLUSIA COUNTY-INLAND VOLUSIA COUNTY-
158 PM EDT SAT AUG 21 2004

...STRONG STORMS CAPABLE OF PRODUCING WINDS UP TO 50 MPH AND SMALL
HAIL OVER VOLUSIA COUNTY...

AT 156 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
CLUSTER OF STRONG STORMS CAPABLE OF PRODUCING STRONG WINDS AND SMALL
HAIL...IN ADDITION TO VERY HEAVY DOWNPOURS OVER VOLUSIA COUNTY.
AREAS AFFECTED INCLUDE LAKE HELEN...CASSADEGA AND REACHING NEAR THE
COAST FROM ORMOND BEACH SOUTH TO NEW SMYRNA BEACH. STORMS WERE
MOVING NORTHEAST AROUND 10 MPH.

IF THE STORM STRENGTHENS FURTHER...A WARNING WILL BE ISSUED.

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