SPC AC 011700
   
   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1200 PM CDT SAT MAY 01 2004
   
   VALID 021200Z - 031200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 35 SSE
   HUM 55 WSW SEM 20 SE HSS 20 SW EKN 10 E PSB 25 WSW SYR 30 NNE SYR 40
   ESE UCA 35 NW EWR 20 NNW ACY 20 SE SBY ...CONT... 15 N MLB 10 WSW
   PIE.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 SW JBR 20 SE FYV
   15 NNW TOP 45 SSW FOD 45 ENE ALO RFD 10 ENE DNV 30 WSW OWB 25 SW
   JBR.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 SSW LCH 20 ENE CBM
   40 NNW CSV 10 ENE CAK 15 SW ERI ...CONT... 15 N HUL 20 E 3B1 15 ESE
   LCI 15 NNE ORH 10 NW BID ...CONT... PBI 65 W MIA.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM PORTIONS OF NY/PA/NJ SWD
   INTO THE SERN STATES/FL...
   
   ...SYNOPSIS...
   DEEP AND PROGRESSIVE MID-LEVEL TROUGH WILL TRANSLATE FROM THE MS
   VALLEY EWD ACROSS THE ERN THIRD OF THE NATION WITH MODERATE TO
   STRONG HEIGHT FALLS OF 60-120M SPREADING EWD THROUGH THE NRN/CNTRL
   APPALACHIANS INTO THE MID ATLANTIC COAST AND NERN STATES. AT THE
   SURFACE...STRONG COLD FRONT INITIALLY FROM THE UPPER OH VALLEY SWWD
   INTO THE CNTRL GULF COAST WILL RAPIDLY PUSH EWD...LIKELY EXTENDING
   FROM LOW PRESSURE OVER N-CNTRL NY SWD ALONG THE LEE OF THE
   APPALACHIANS INTO THE FL PNHDL BY MID AFTERNOON. THIS FEATURE WILL
   BE THE PRIMARY FOCUS FOR STRONG TO SEVERE TSTM DEVELOPMENT ON THE
   DAY 2 PERIOD.
   
   ...NY/PA/WRN NEW ENGLAND SWD INTO VA/NC...
   SLY 40-50KT LLJ AHEAD OF MID-LEVEL TROUGH WILL ADVECT INCREASING
   AMOUNTS OF MOISTURE NWD INTO PRE-FRONTAL AIRMASS WITH 60-65F
   DEWPOINTS LIKELY AS FAR N AS ERN NY/ERN PA/NJ BY AFTERNOON. ALTHOUGH
   CLOUDS/PRECIPITATION AND WEAK MID-LEVEL LAPSE RATES WILL LIMIT
   OVERALL DESTABILIZATION...DEEP-LAYER FORCING AHEAD OF MID-LEVEL
   TROUGH COUPLED WITH SLAB ASCENT ALONG COLD FRONT AND MODEST
   BOUNDARY-LAYER MOISTURE SHOULD SUPPORT THE DEVELOPMENT AND EWD
   PROGRESSION OF LOW-TOPPED SQUALL LINE. LARGELY MERIDIONAL COMPONENT
   OF TROPOSPHERIC WIND FIELDS AND THE WEAK INSTABILITY SHOULD PRECLUDE
   A WIDESPREAD WIND EVENT...HOWEVER ISOLATED DAMAGING WINDS WILL BE
   POSSIBLE WITH ANY BOWING/LEWP STRUCTURES EMBEDDED WITHIN SQUALL
   LINE.
   
   ...SERN STATES/FL...
   PRE-FRONTAL LINE OF TSTMS WILL LIKELY BE ONGOING INITIALLY FROM
   PORTIONS OF ERN TN/NRN GA SWWD THROUGH AL INTO SERN MS.
   RICHER BOUNDARY-LAYER MOISTURE WITH DEWPOINTS IN THE MID 60S TO
   LOWER 70S COUPLED WITH DIABATIC HEATING SHOULD CONTRIBUTE TO GREATER
   INSTABILITY THAN POINTS TO THE N WITH MLCAPES APPROACHING 1000-1500
   J/KG BY AFTERNOON OVER MUCH OF FL NWD INTO SRN/ERN GA AND SC.
   WEAKER DYNAMIC FORCING ON SRN FRINGE OF MID-LEVEL TROUGH WILL LIKELY
   LEAD TO A SLOWER FRONTAL MOTION AND GENERALLY WEAKER LOW-LEVEL
   CONVERGENCE. NONETHELESS...THIS INSTABILITY IN CONJUNCTION WITH
   MARGINALLY STRONG DEEP-LAYER SHEAR OF 25-30KTS SHOULD LEAD TO A
   GRADUAL INCREASE IN PRE-FRONTAL TSTM INTENSITY THROUGH THE AFTERNOON
   HOURS WITH ISOLATED DAMAGING WINDS BEING THE PRIMARY SEVERE WEATHER
   THREAT.
   
   ADDITIONALLY...DOWNSTREAM STRONG TO POTENTIALLY SEVERE TSTMS WILL BE
   POSSIBLE ALONG THE ERN FL SEA BREEZE AS MID-LEVEL FLOW STRENGTHENS
   TO 25-35KTS.
   
   ...IL/E-CNTRL MO...
   COLD MID-LEVEL TEMPERATURES /I.E. -27 TO -30C AT 500MB/ AND DAYTIME
   HEATING IN POST FRONTAL AIRMASS WILL LEAD TO QUITE STEEP LOW TO
   MID-LEVEL LAPSE RATES AND A WEAKLY UNSTABLE ENVIRONMENT BY
   AFTERNOON. LOW-TOPPED CONVECTION CAPABLE OF MARGINALLY SEVERE
   HAIL/GRAUPEL WILL BE POSSIBLE WITH THE STRONGEST STORMS INTO EARLY
   EVENING. EXPECT CONVECTION TO DIMINISH THEREAFTER WITH LOSS OF
   DAYTIME HEATING.
   
   ..MEAD.. 05/01/2004
   
   ...NOTICE...
   FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
   LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
   GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
   HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
   INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
   
   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED FOR 0800Z