SPC AC 091243
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0743 AM CDT SUN MAY 09 2004
   
   VALID 091300Z - 101200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 75 ESE
   ANJ 25 ESE HTL 15 ESE CID 10 NE FNB 20 N RSL 10 WSW DDC 20 NW LBL 45
   E LAA 30 NW MCK 30 WSW MHE 55 N ATY 25 NNE RRT.
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 NE
   ORF 45 WSW MRB 15 NW LBE 25 ESE FKL 35 NE BFD 20 SSW BGM 15 SW ISP.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 SSW ART 10 NE ALB
   30 SSE EWB.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 15 ESE FHU 20 SSW ABQ
   20 W LVS 50 S LAA 45 WNW GLD 30 SSE SNY 35 NNE RWL 35 SE SUN 75 NE
   SVE 20 ENE RBL 15 SE EKA 15 E 4BK 30 NNW SLE 35 NE PDX 30 SSE 3DU 50
   N SHR 30 SE 81V 35 SSE PHP 40 WNW PIR 55 NNE MOT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM LRD 25 ENE BWD 35 NNE
   MWL 15 ESE ADM 35 SW PGO 20 W TXK 15 E GGG 10 N LFK 45 ENE PSX.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 SW ILM 50 WNW FLO
   35 NE MGR 25 NNE DHN 45 SE MEI 30 SSW GWO 50 NE LIT 25 ENE ARG 30
   WNW HOP 15 SE BWG 35 S LEX 25 SSE LUK 25 NE IND 15 SSE UIN 10 SSE
   FLV 50 WSW P28 55 ESE LBB 30 SE P07.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM WRN KS INTO THE UPPER
   GREAT LAKES...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS MUCH OF THE MIDDLE
   ATLANTIC REGION...
   
   ...CENTRAL PLAINS TO UPPER GREAT LAKES...
   
   OVERNIGHT MCS HAS PROPAGATED SEWD ACROSS THE CENTRAL PLAINS/MID MS
   VALLEY AND WEAKENED CONSIDERABLY DESPITE THE PRESENCE OF MODEST LLJ
   OVER CENTRAL KS.  THIS ACTIVITY WILL LIKELY CONTINUE TO WEAKEN AS
   THE MORNING PROGRESSES WITH MOISTURE/INSTABILITY EXPECTED TO RETURN
   IN THE WAKE OF THIS FEATURE NEWD ACROSS NEB INTO MN BY EARLY
   AFTERNOON.  LATEST MODEL GUIDANCE CONTINUES TO FAVOR RAPID HEATING
   AHEAD OF COLD FRONT/DRY LINE FROM NWRN KS INTO WRN MN BY MID
   AFTERNOON.  STEEP LOW-MID LEVEL LAPSE RATES AND FOCUSED MASS FIELDS
   ALONG BOUNDARY FAVOR CONVECTIVE INITIATION OVER MN BY 21Z.  IN
   ADDITION TO COLD FRONTAL FORCING...IT APPEARS STRENGTHENING WARM
   ADVECTION ALONG RETREATING WARM FRONT WILL BECOME INCREASINGLY
   CONDUCIVE FOR THUNDERSTORM DEVELOPMENT AHEAD OF UPPER SPEED MAX
   DIGGING INTO THE UPPER MS VALLEY.  12Z SOUNDINGS FROM THIS REGION
   INDICATE VERY STEEP LAPSE RATES ARE IN PLACE...ON THE ORDER OF 8
   C/KM...WITH HIGHER MOISTURE EXPECTED TO STREAM NEWD/MIX DOWN AS
   BOUNDARY LAYER DEEPENS WITH DAYTIME HEATING.  FORECAST SOUNDINGS
   SUGGEST AIRMASS WILL BECOME STRONGLY UNSTABLE AND HIGHLY SUPPORTIVE
   OF LARGE HAIL WITH ANY SUPERCELLS THAT DEVELOP.  ALTHOUGH HAIL WILL
   BE COMMON WITH MUCH OF THIS ACTIVITY IT APPEARS ISOLATED TORNADOES
   MAY OCCUR WITHIN STRONGER WARM ADVECTION ZONE. EVENING ACTIVITY MAY
   EVOLVE INTO AN MCS AS IT PROPAGATES EWD ACROSS THE GREAT LAKES DUE
   TO VEERING LLJ INTO MI.
   
   STRONG HEATING WILL CONTRIBUTE TO SCATTERED THUNDERSTORM DEVELOPMENT
   SWWD ALONG COLD FRONT/DRY LINE INTO WRN KS WHERE WEAKER VERTICAL
   SHEAR WILL SUPPORT SLOWER MOVING LESS ORGANIZED ACTIVITY.
   
   ...MIDDLE ATLANTIC REGION...
   
   12Z SOUNDING FROM WAL INDICATES DEEP WLY COMPONENT AND STEEP LAPSE
   RATES...7 C/KM FROM 850-500MB...THROUGH MID LEVELS.  STRONG BOUNDARY
   LAYER HEATING IS EXPECTED ACROSS WARM SECTOR AIRMASS FROM PA INTO
   NRN VA...IMMEDIATELY WEST OF COOLER LOW LEVEL AIRMASS THAT HAS YET
   TO RETREAT ACROSS SRN NEW ENGLAND. IT APPEARS THUNDERSTORMS MAY TEND
   TO FOCUS ALONG THIS DEMARKATION WHERE RAPID HEATING AND LOW LEVEL
   CONVERGENCE WILL BE MAXIMIZED. MARGINAL DEEP LAYER SHEAR WILL FAVOR
   ISOLATED MULTI-CELL UPDRAFTS CAPABLE OF PRODUCING AT LEAST LARGE
   HAIL...AND TO A LESSER DEGREE DAMAGING WINDS DUE TO WEAKER DEEP
   LAYER SHEAR.
   
   ..DARROW/CROSBIE.. 05/09/2004
   
   ...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 1 OUTLOOK IS SCHEDULED FOR 1630Z