Tornado in Florida, May 17, 2002

WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
315 PM EDT FRI MAY 17 2002

CURRENTLY...LAPS SOUNDING DATA DEPICTS A VERY MOIST AND UNSTABLE AIR
MASS COVERING THE ENTIRE FORECAST AREA EARLY THIS AFTERNOON. 88D
RETURNS ALREADY DEPICTING DEVELOPING CONVECTION ALONG THE WEST COAST
SEA BREEZE. AS THE AFTERNOON CONTINUES EXPECT THE WEST COAST BOUNDARY
TO MOVE INLAND WHERE WE SHOULD SEE THE BEST AREAL COVERAGE AND
INTENSITY OF STORMS DURING THE LATE AFTERNOON AND EARLY EVENING
HOURS...WHERE THE BEST SEA BREEZE CONVERGENCE SHOULD SET UP. BASED ON
THIS WILL GO WITH SCATTERED CATEGORY (50%) EVENING POPS INTERIOR. AS
FOR THE COASTAL ZONES...MARINE STABILITY IN WAKE OF THE SEA BREEZE
SHOULD KEEP POP CHANCES LOWER SO WILL WORD FOR MAINLY INLAND WITH A
20-30% CHANCE.

SHORT TERM...ZONAL FLOW OF THE PAST SEVERAL DAYS WILL TRANSITION
INTO A OMEGA TYPE BLOCKING PATTERN ACROSS THE COUNTY AS WE MOVE INTO
THE WEEKEND AND NEXT WEEK. DIFFERENCES EXIST WITH THE MODELS THIS
AFTERNOON AND CENTER AROUND FRONTAL MOVEMENT AND TIMING OF CLEARING
FROM NORTH TO SOUTH IN WAKE OF THE FRONT BY LATE IN THE WEEKEND.
AVN FOR THE LAST FEW DAYS HAS BEEN FLIP-FLOPPING AROUND WITH ITS
SOLUTIONS (ONE DAY FAST THE NEXT SLOW)...WHILE THE ETA/NGM HAVE
MAINTAINED SOMEWHAT MORE CONSISTENCY FROM RUN TO RUN. AVN NOW IS SOME
12 HOURS FASTER WITH RESPECT TO THE MOVEMENT OF THE FRONT AND
CLEARING IN ITS WAKE THROUGH THE FA WHILE THE ETA/NGM ARE MUCH
SLOWER. THE ETA.NGM ARE SLOWER GIVEN THEY ARE HANGING BACK BOTH THE
850/500MB TROUGHS TO OUR WEST...WHICH LOOKS MORE REALISTIC GIVEN THE
EVOLVING UPPER AIR PATTERN MENTION ABOVE. WITH THIS IN MIND WILL LEAN
TOWARD A BLEND OF ETA/NGM SOLUTIONS THIS PACKAGE.

IN ANY EVENT SOME MUCH NEEDED RAINFALL IS ON TAP FOR THE FA DURING
THE NEXT 24 TO 48 HRS AS SHORT WAVE TROUGH AND ATTENDANT COLD FRONT
MOVE ACROSS THE FA. HIGH PWS...SUFFICIENT INSTABILITY AND GOOD LIFT
FROM FEATURES MENTIONED ABOVE WILL RESULT IN SOME HIGH POPS THROUGH
MUCH OF THE UPCOMING WEEKEND...WITH A GRADUAL CLEARING TREND DVLPG
FROM NORTH TO SOUTH BY MONDAY. SOUTHWEST STEERING FLOW ON SATURDAY
WILL AGAIN FAVOR HIGHEST POPS INTERIOR...THEN AS THE FRONT APPROACHES
SATURDAY NIGHT AND SUNDAY...MORE UNIFORM POP COVERAGE EXPECTED. WITH
THE EXPECTED CLOUD COVER/PRECIP...MAX TEMPS WILL BE RUNNING SOME 3 TO
5 DEGREES BELOW SEASONAL LEVELS FOR THE NEXT FEW DAYS...WHICH WILL
CONTINUE INTO NEXT WEEK IN WAKE OF THE FRONT. FWC/MAV NUMBERS ARE
CLOSE...SO WILL BLEND.

EXTENDED(TUES-FRI)...HIGH PRESSURE BUILDING IN FROM THE NORTH IN WAKE
OF THE FRONT WILL KEEP THINGS DRY THROUGH THE PERIOD WITH A BRISK
NORTHEASTERLY WIND FLOW. TEMPS TO CONTINUE SLIGHTLY BELOW SEASONAL
LEVELS.

MARINE...SOUTH TO SOUTHWEST FLOW WILL BE ON THE INCREASE OVER THE
NEXT 24 TO 36 HOURS AHEAD OF THE FRONT WHICH MAY RESULT IN SCEC
CONDITIONS BY LATE TOMORROW. FOR NOW WILL HIGHLIGHT THIS IN THE CWF
PACKAGE. AS THE FRONT MOVES THROUGH THE WINDS WILL SHIFT INTO THE
NORTH AND THEN NORTHEAST AND MAY APPROACH LOW END SCA LEVELS AS WE
HEAD INTO THE BEGINNING OF NEXT WEEK.

THANKS FOR COORD KMLB

PRELIMINARY S
BKV 070/085 067/082 2654
TPA 076/086 073/083 2655
GIF 072/089 070/083 5655
SRQ 074/085 073/083 2655
FMY 072/089 072/086 2555

.TBW...NONE.

MCMICHAEL