746 
FXUS62 KMLB 080751
AFDMLB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
345 AM EDT THU APR  8 2004

.DISCUSSION...CURRENTLY...SFC-H85 RIDGE AXIS EXTENDS FROM THE SW ATLC
TO THE NW CARIB COMBINING WITH A SFC-H70 SHORT WAVE TROF OVER THE LWR
MS VALLEY TO PRODUCE A FAIRLY TIGHT PGRAD ACROSS THE GOMEX REGION...
GENERATING A STEADY S/WRLY FLOW THROUGH H50.  AVAILABLE MOISTURE HAS
INCREASED WITH THE ONSET OF THE SRLY WINDS...PW VALUES RANGE 1.0-
1.3. UPSTREAM...MOISTURE OVER THE NRN GOMEX DECREASES SUBSTANTIALLY
WITH H100-H50 MEAN RH VALUES AOB 50%.

TODAY/TONIGHT...THE SHORT WAVE TROF WILL RIDE UP THE BACKSIDE OF THE
ATLC RIDGE TODAY. RESULTING LOW/MID LVL FLOW WILL VEER W/SW BY AFTN
WITH THE JAX/MIA PGRAD TIGHTENING TO 5-6MB BY ETA12 INDICATIONS...
WHICH IS CAPABLE OF SUPPORTING 20KT WINDS BY GEOSTROPHIC ESTIMATES.
THE DEVELOPING WRLY FLOW WILL TAP THE DRY AIR OVER THE NRN GOMEX AND
PULL IT ACROSS THE NRN PENINSULA TODAY.  DRY AIR ADVECTION IS
ALREADY OCCURRING WITH THE 50% H100-H50 MEAN RH LINE ALREADY
ENCROACHING ON THE W CENTRAL PENINSULA.

WRLY FLOW WILL BE TOO STRONG FOR THE ECSB TO DEVELOP...AND DRY AIR
ADVECTION WILL DRAIN THE LCL STORM ENVIRONMENT OF MOST OF ITS FUEL.
WILL REDUCE POPS BLO 20% FOR THE NRN CWA...20% FOR THE SRN CWA.
WRLY FLOW AND LOW CLOUD COVER WILL ALLOW TEMPS TO WARM A GOOD 4-8F
DEG ABV CLIMO.

FRI-SUN...STRONG SUB-TROPICAL JET AXIS WILL REMAIN ACROSS
CENTRAL/SOUTH FLORIDA AND SEVERAL WEAK IMPULSES WILL PASS. DEEP
LAYER MOISTURE WILL REMAIN QUITE LOW AND INITIAL THOUGHTS WERE TO
REMOVE POPS FOR FRI. HOWEVER...MARGINAL MOISTURE...WEAK RISING MOTION
FROM SHORTWAVE...APPROACHING/WEAKENING WIND SHIFT BOUNDARY...AND
LOCAL FOCUS ALONG SEA BREEZE BOUNDARIES SHOULD BE ENOUGH TO FORCE
ISOLATED AFTERNOON SHOWERS. WILL RETAIN DRY FORECAST FOR SAT-SUN AS
NEXT SYSTEM LIKELY TO HOLD OFF UNTIL LATER SUN. TEMPS GENERALLY A
CATEGORY ABOVE CLIMO INLAND AND NEAR CLIMO ALONG THE COAST. BY LATE
SUNDAY...A SIGNIFICANT LONGWAVE TROUGH WILL CONTINUE TO EVOLVE AND
MOVE EAST FROM THE MS RIVER VALLEY...ACQUIRING A SLIGHT NEGATIVE
TILT. WINDS WILL VEER TO S/SW AND STRENGTHEN...ALLOWING FOR A QUICK
RETURN OF DEEP MOISTURE. SCATTERED SHOWERS AND STORMS EXPECTED AHEAD
OF THE SYSTEM SUNDAY NIGHT.

MON-THU...STRONG ASCENT AHEAD OF DEEP TROUGH AND ASSOCIATED FRONTAL
BOUNDARY WILL PRODUCE AN INCREASING CHANCE FOR SHOWERS/STORMS
MONDAY ALONG WITH GUSTY WINDS AND CLOUDY SKIES. EXACT TIMING AND
STRENGTH OF CONVECTION STILL UNCERTAIN THIS FAR OUT...SO WILL NOT
ATTEMPT TO REFINE FORECAST ANY FURTHER AT THIS POINT. EXTENDED
GUIDANCE HOWEVER CONTINUES TREND OF 10-15 DEGREE COOLING FOR CURRENT
WARM TEMPS AFTER FROPA FOR EARLY-MID WEEK. HAVE MODIFIED MAX/MIN
TEMPS DOWNWARD AN AVERAGE OF 5 DEGREES...FEATURING MAXS IN THE
MID/UPPER 70S AND MINS IN THE 50S...BUT NOT QUITE AS LOW AS GFS MOS
YET. LOOKS LIKE A NICE STRETCH OF DRY WX AFTER FROPA...WITH TEMPS A
CATEGORY OR TWO BELOW NORMAL FOR A CHANGE.

&&

.MARINE...WILL RAISE SMALL CRAFT EXERCISE CAUTION THIS MORNING FOR
OFFSHORE WINDS 15-20 KT...CONTINUING INTO EARLY FRIDAY. APPROACH OF
WEAKENING BOUNDARY FRIDAY WILL CAUSE WINDS TO BECOME LIGHT WITH
LOCAL AFTERNOON SEAS BREEZES FRI AND SAT. FLOW WILL SHIFT TO
S/SW COMPONENT SUN AND GRADUALLY INCREASE WELL IN ADVANCE OF
COLD FRONT...LIKELY REACHING ADVISORY LEVELS BY MONDAY...AND
CONTINING STRONG AFTER THE FRONTAL WIND SHIFT EARLY TUESDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  87  62  80  62 /  10  10  20  10
MCO  85  64  87  63 /  10  10  10  10
MLB  87  64  84  63 /  20  10  20  10
VRB  87  65  84  62 /  20  10  20  10

&&

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

&&

$$

SHORT TERM...BRAGAW
LONG TERM...SPRATT