SPC AC 200600
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0100 AM CDT TUE APR 20 2004
   
   VALID 201200Z - 211200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 15 SE
   DAL 10 NNE FTW 50 NNW FTW 35 SW OKC 20 N END 30 N HUT 30 SSE HSI 30
   ENE BUB 60 ENE ANW 35 SSW MHE 35 ESE MHE 20 NNW SPW 15 E MCW 40 WNW
   DBQ 45 ESE DBQ 30 W MMO 10 ENE BMI 15 SE DEC 30 NNE SLO 10 SSW MVN
   35 NNW DYR 35 SSW JBR 20 SSW LIT 25 WSW TXK 40 NW TYR 15 SE DAL.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 N HSE 10 NNW RWI
   40 SE LOZ 55 SW CKV 20 NE PBF 15 SSE GGG 15 SE AUS SAT 15 NNE HDO 40
   NW HDO 20 S JCT 30 N JCT 25 ESE ABI 10 SSE FSI 45 SSW END 20 S P28
   40 NNE DDC 35 ENE AKO 50 WSW SNY 50 NNW 4FC 35 WSW VEL 30 E U24 55
   SE ELY 50 NE TPH 55 WNW TPH 20 WSW NFL 40 ENE SVE 4LW 65 SSW PDT 40
   W PUW 35 WNW S06 10 SE FCA 25 WNW HVR 25 N SDY 25 NW P24 30 E MOT 65
   NNW DVL ...CONT... 25 N JHW 10 WSW IPT 25 S ACY.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF FAR SE
   SD...IA...IL...MO...AR...OK...NE TX...KS...ERN NEB...
   
   ...ERN KS/WRN MO/FAR NW AR/NE OK...
   
   SFC ANALYSIS CURRENTLY SHOWS A MOISTURE AXIS WITH SFC DEWPOINTS IN
   THE LOWER TO MID 60S F EXTENDING NEWD FROM OK ACROSS CNTRL MO. AS A
   SHORTWAVE TROUGH MOVES EWD INTO THE CNTRL PLAINS TODAY AND INTERACTS
   WITH THE LOW-LEVEL MOISTURE...THE STAGE WILL BE SET FOR ISOLATED TO
   SCATTERED SEVERE STORMS ACROSS THE OZARK REGION AND CNTRL PLAINS.
   
   WATER VAPOR IMAGERY CURRENTLY SHOWS A DRY SLOT IN PLACE ACROSS W TX
   AND THIS FEATURE WILL DRIFT NEWD ACROSS OK INTO SERN KS AND SWRN MO
   BY THIS AFTERNOON. THE STRONGEST SFC HEATING SHOULD OCCUR IN THIS
   REGION AND THIS COMBINED WITH MID 60 F SFC DEWPOINTS WILL LIKELY
   RESULT IN MODERATE INSTABILITY WITH MLCAPE VALUES FROM 1500 TO 2000
   J/KG. A SHORTWAVE TROUGH WILL APPROACH THE SLIGHT RISK AREA TODAY
   AND THIS WILL CAUSE LARGE-SCALE ASCENT TO OVERSPREAD THE REGION. A
   SFC LOW IS FORECAST TO DEEPEN AND MOVE NEWD ACROSS THE CNTRL PLAINS
   THIS AFTERNOON AND CONVECTIVE INITIATION SHOULD OCCUR ALONG THE SFC
   TROUGH ACROSS ERN KS AND CNTRL OK. FORECAST SOUNDINGS FOR THIS
   AFTERNOON SHOW FAIRLY UNIDIRECTIONAL SHEAR PROFILES WITH 30 TO 35 KT
   OF DEEP LAYER SHEAR. THIS SHOULD FAVOR A LINEAR FORM OF CONVECTION
   WITH ISOLATED SUPERCELLS POSSIBLE ESPECIALLY EARLY IN THE
   DEVELOPMENT OF THE LINE. SUPERCELLS WILL HAVE THE POSSIBILITY FOR
   LARGE HAIL AND ISOLATED SIGNIFICANT HAIL WILL BE POSSIBLE NEAR THE
   BEST INSTABILITY ACROSS ERN KS WHERE LAPSE RATES ARE FORECAST TO BE
   THE STEEPEST. THE LINE SHOULD PROGRESS EWD ACROSS MO AND WRN AR
   DURING THE EVENING AND AN ISOLATED WIND DAMAGE WILL BE POSSIBLE WITH
   THE STRONGER CELLS WITHIN THE LINE.
   
   ...UPPER MIDWEST/OH VALLEY...
   
   A SFC LOW WILL DEEPEN AND MOVE NEWD ACROSS THE CNTRL PLAINS TODAY AS
   A WARM FRONT LIFTS NEWD ACROSS THE UPPER MIDWEST AND OH VALLEY.
   CONVECTION WILL LIKELY BE ONGOING ALONG THE FRONT THIS MORNING.
   INSTABILITY SHOULD BE LIMITED SOMEWHAT DUE TO EXTENSIVE CLOUD COVER
   ACROSS THE REGION THIS MORNING. HOWEVER...MARGINAL INSTABILITY
   SHOULD DEVELOP AHEAD OF THE WARM FRONT AND THIS WILL HELP THE
   CONVECTION TO BE SUSTAINED AS IT SPREADS NEWD INTO IA...IL AND IND
   THIS AFTERNOON. FORECAST SOUNDINGS SHOW ABOUT 40 KT OF DEEP LAYER
   SHEAR AND THIS SHOULD BE ENOUGH FOR ISOLATED SEVERE STORMS NEAR PEAK
   HEATING LATE THIS AFTERNOON CONTINUING THROUGH EARLY EVENING. THE
   BEST SEVERE THREAT SHOULD BE ACROSS WRN IL AND IA WHERE LAPSE RATES
   SHOULD BE STEEPEST AND 500 MB TEMPS WILL BE COLDER RANGING FROM -15
   TO -17 C.
   
   ..BROYLES/CROSBIE.. 04/20/2004
   
   ...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 1300Z