Severe Thunderstorm Warning 78, NWS New York, NY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1019 AM EDT FRI AUG 16 2002

WEAK WAVES MOVG THRU THE AREA THIS AFTN AND DAYTIME HEATING WITH
CONVECTIVE TMPS REACHED COULD TRIGGER A FEW TSTMS. CAPES GENERALLY
BELOW 1000. WBZ ARND 12K AND MOIST ATMOSPHERE WL PRECLUDE ANY SVR
WX. WITH SLOW MOVG STORMS AND PRECIPITABLE WATERS NR 2 INCHES COULD
SEE HVY RAINS WITH THE STORMS.

***PREVIOUS DISCUSSION***

SHORT RANGE WX DISC...WELL START THE DAY WITH CLOUDY SKIES AND HIGH
HUMIDITY. AS OF 06Z...BKN STRATUS CLOUDS COVER LONG ISLAND AND
SOUTHERN CT AS A PATCH OF MID LVL CLOUDS ADVECT NEWD ACROSS THE
REGION.

FOR TODAY...THE FCST CHALLENGES INCLUDE THE...

POTENTIAL FOR A HEAT ADVISORY...BKN MID AND UPPER LVL CLOUDS ALONG
WITH THE DEVELOPMENT OF LOW LVL CLOUDS WILL SIGNIFICANTLY FILTER THE
SUNSHINE...LIMITING HEATING AND PRODUCING AFTERNOON TEMPS A DEGREE
OR TWO LOWER THAN YESTERDAY AFTERNOON...WHEN THE HEAT INDEX PEAKED
AT 99 DEGS FOR 1 HOUR AT CENTRAL PARK. I WILL MOST CLOSELY FOLLOW
THE ETA MOS GUIDANCE VALUES FOR TEMPS AND DEW PT TEMPS...WHICH WILL
PRODUCE HEAT INDICES IN THE UPPER 90S IN URBAN NE NJ AND THE MID 90S
IN NYC. THUS...LIKE YESTERDAY...WE WILL NOT ISSUE A HEAT ADVISORY
FOR NYC.

POTENTIAL FOR A SMALL CRAFT ADVISORY...UNLIKE YESTERDAY...ALTHOUGH
IM EXPECTING SEA BREEZES TO DEVELOP BETWEEN 15 AND 18Z...THE
SYNOPTIC SCALE GRADIENT WILL BE RELAXING. THE WIND SPEEDS SHOULD
REMAIN AROUND 20 KNOTS WITH SEAS AROUND 4 FT OVERALL. HOWEVER...I
WOULDNT BE SURPRISED IF THE AMBROSE LIGHT TOWER BUOY REPORTED A 25
KNOT WIND FOR AN HOUR OR TWO. AT THIS TIME...ILL HOLD OFF ON
ISSUING ANY SMALL CRAFT ADVISORY FOR THE ATLANTIC COASTAL WATERS
SOUTH OF LONG ISLAND.

POTENTIAL FOR TSTMS...THE MAIN TRIGGERING MECHANISMS WILL BE THE
UPSTREAM WEAK UPPER LVL SHORT WV MVG SEWD TOWARD THE REGION AND THE
DEVELOPMENT OF SEA BREEZES. WITH LOW LVL MOISTURE IN PLACE AND
INCREASING INSTABILITY...IM EXPECTING SCT AFTERNOON TSTMS
DEVELOPING INITIALLY ALONG THESE BOUNDARIES THEN SLOWING ADVECTING
EWD AROUND 10 KTS. WITH PW CONTENTS BETWEEN 1.5 AND 2.0
INCHES...TSTMS WILL HAVE THE POTENTIAL FOR PRODUCING HVY RAINFALL
AND LOCALIZED URBAN FLOODING. ILL BE FORECASTING A 40 PCT POP
INLAND AND 30 PCT ALONG THE COAST...WHICH WILL BE CARRIED INTO THIS
EVENING.

REMAINDER OF THE FORECAST...A SERIES OF WEAK UPPER LVL SHORT WVS AND
LOW LVL TROUGHS WILL MV ACROSS THE REGION THROUGH SAT...FOLLOWED BY
A STRONGER COLD FRONT LATE SUN...WHICH COULD PRODUCE SEVERE WEATHER
ALONG A PRE-FRONTAL SQUALL LINE FOLLOWED BY A FRESH NEW AIR MASS TO
START THE WEEK.

CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.

GC