SPC AC 160737
   
   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0237 AM CDT FRI APR 16 2004
   
   VALID 171200Z - 181200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 35 WSW
   P28 40 NNE DDC 25 WSW SUX 25 NNW HON 10 WSW HIB 35 NNW HTL 30 NNW
   SYR 15 S BFD 35 NNE DAY 30 ENE DSM 30 WNW EMP 35 WSW P28.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 W DUG 80 NW TCS 20
   W RTN 20 WNW LIC 20 N GJT 60 SW DRA 30 N BFL 35 E UKI 20 NW MHS 75 N
   4LW 45 WSW S80 25 NNE 3TH 80 NW FCA ...CONT... 30 ENE PWM 30 NW EWR
   30 W MGW 55 WNW HTS 15 E DNV OTM 35 ESE EMP 55 SW SPS 20 SE DRT.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE MID/UPR MS
   VLYS AND GRT LKS...
   
   ...SYNOPSIS...
   PACIFIC SPEED MAX NOW DROPPING S FROM NEAR 45N/135W EXPECTED TO
   ROUND BASE OF MAIN OFFSHORE TROUGH BY 12Z SATURDAY.  THE IMPULSE
   SHOULD EJECT ENE OVER THE SRN GRT BASIN LATER SATURDAY...AND REACH
   THE CNTRL RCKYS AROUND 12Z SUNDAY AS UPSTREAM DISTURBANCE QUICKLY
   REPLACES IT OFF THE SRN CA CST.  DOWNSTREAM FROM THE LEAD SHORTWAVE
   ...HEIGHTS SHOULD CONTINUE TO RISE ACROSS THE SRN PLNS/LWR MS VLY
   AND MUCH OF THE EAST AS THE MAIN BELT OF WLYS RETREATS N ACROSS THE
   GRT LKS/NEW ENGLAND.
   
   EJECTION OF SWRN IMPULSE WILL BE ACCOMPANIED BY SIGNIFICANT LEE
   CYCLOGENESIS OVER ERN CO/WY.  THE LOW SHOULD REACH SRN SD BY 12Z
   SUNDAY AS ASSOCIATED WARM FRONT LIFTS N INTO NRN IA/WRN WI AND SRN
   MI.  FARTHER E...THE SAME BOUNDARY WILL LIKELY SETTLE SWD AS A COLD
   FRONT ACROSS NY AND NEW ENGLAND AS A FAST-MOVING IMPULSE SWEEPS E
   ALONG UPPER JET IN SRN ONTARIO/QUEBEC.
   
   ...MID/UPR MS VLY TO LWR GRT LKS...
   AN AREA OF THUNDERSTORMS...PROBABLY IN THE FORM OF AN ELEVATED
   MCS...MAY BE IN PROGRESS AT THE START OF THE PERIOD OVER PARTS OF WI
   AND LWR MI.  THIS ACTIVITY WILL BE FED BY BRANCH OF LOW LEVEL JET
   ASSOCIATED WITH UPPER IMPULSE CROSSING SRN ONTARIO AND SHOULD SPREAD
   E TOWARD THE LWR GRT LKS LATER IN THE DAY.  SURFACE HEATING MAY
   INITIATE A FEW SURFACE-BASED STORMS ALONG CONVECTIVE OUTFLOW AND/OR
   ALONG COLD FRONT OVER NRN IL/NRN IND/OH/NY AND NW PA.  30-40 KT DEEP
   WLY SHEAR AND AVAILABILITY OF STEEP MID LEVEL LAPSE RATES ASSOCIATED
   WITH ELEVATED MIXED LAYER PLUME MAY SUPPORT SOME BOWING SEGMENTS
   WITH HIGH WIND AND A LITTLE HAIL BEFORE FORCING CONTINUES E BEYOND
   INSTABILITY AXIS LATE IN THE DAY.
   
   LATER IN THE PERIOD...MAINLY AFTER 00Z...EXPECT ANOTHER ROUND OF
   STRONG TO SEVERE STORMS TO DEVELOP ALONG AND N OF DEVELOPING WARM
   FRONT IN THE UPR MS VLY.  THIS ACTIVITY WILL BE FED BY DIURNAL AND
   SYNOPTICALLY-STRENGTHENED LOW LEVEL JET DOWNSTREAM FROM EJECTING
   UPPER TROUGH.  THESE STORMS WILL PROBABLY SPREAD NWD ACROSS MUCH OF
   MN/WI AND NW MI BY 12Z SUNDAY. INCREASING BOUNDARY LAYER MOISTURE
   RETURN UPSTREAM OVER THE CNTRL PLNS AND FAIRLY COOL MID LEVEL
   TEMPERATURES /AROUND MINUS 16C AT 500 MB/ SUGGEST A GOOD CHANCE FOR
   HAIL IN THE STRONGER STORMS.  IF CAPPING IS NOT EXCESSIVE AND/OR IF
   FRONTAL CONVERGENCE IS SUFFICIENT...A FEW SURFACE-BASED SUPERCELLS
   MAY FORM EARLY IN THIS EVOLUTION ACROSS  PARTS OF IA/NW IL AND
   PERHAPS FAR ERN NEB.  WITH SBCAPE AOA 2500 J/KG AND LONG/CURVED
   HODOGRAPHS...THESE STORMS COULD YIELD VERY LARGE HAIL/HIGH WIND AND
   PERHAPS A COUPLE TORNADOES BEFORE EVOLVING INTO AN MCS.
   
   ...SW TX NWD INTO WRN OK AND WRN/CNTRL KS...
   THE DRY LINE WILL BECOME BETTER ESTABLISHED ACROSS THE SRN AND CNTRL
   HI PLNS ON SATURDAY AS SWLY UPPER FLOW STRENGTHENS DOWNSTREAM FROM
   GRT BASIN TROUGH AND BOUNDARY LAYER MOISTURE RETURN CONTINUES OVER
   THE LOWER PLAINS.  BUT SATELLITE LOOPS SUGGEST THAT ANTICIPATED
   LARGE SCALE BACKING OF UPPER FLOW WILL ADVECT GREAT QUANTITIES OF
   MULTILAYERED MID AND UPPER CLOUDINESS ACROSS THE SRN HALF OF THE
   PLAINS.  THESE CLOUDS WILL ALSO LIKELY BE ENHANCED BY LEE WAVES E OF
   THE NRN MEXICAN AND NM MTNS.
   
   GIVEN EXPECTED CLOUD COVER...ANTICYCLONIC NATURE OF THE LARGE SCALE
   FLOW AND ABSENCE OF AN OBVIOUS SRN STREAM IMPULSE TO OFFSET THESE
   NEGATIVE FACTORS...THE PROSPECTS FOR DIURNAL...SURFACE-BASED STORMS
   APPEAR LIMITED OVER MOST OF W TX AND WRN OK.  WHILE FAIRLY STEEP MID
   LEVEL LAPSE RATES AND MOISTURE INFLUX MAY SUPPORT SOME SCATTERED MID
   LEVEL CONVECTION THROUGH THE DAY 2 PERIOD...SUCH ACTIVITY WILL
   LIKELY NOT TAP THE BOUNDARY LAYER AND WILL NOT POSE MUCH OF A THREAT
   FOR SEVERE.
   
   FARTHER N...A SOMEWHAT GREATER POTENTIAL FOR SURFACE-BASED STORMS
   WILL EXIST IN KS. THIS REGION SHOULD BE ALONG NWRN FRINGE OF CIRRUS
   CANOPY AND...BY THE END OF THE DAY...MAY EXPERIENCE THE LEADING EDGE
   OF LARGE SCALE ASCENT ASSOCIATED WITH APPROACHING UPPER IMPULSE. 
   DEPTH OF LOW LEVEL CONVERGENCE WILL...HOWEVER...BE LIMITED BY SW
   COMPONENT TO MEAN FLOW...AND MOISTURE AVAILABILITY WILL NOT BE
   EXTENSIVE GIVEN EXPECTED ORIENTATION/ BREADTH OF LOW LEVEL JET. 
   STEEP MID LEVEL LAPSE RATES AND DEEP MIXED/INVERTED VEE ENVIRONMENT
   WILL...HOWEVER...BE FAVORABLE FOR DOWNBURSTS AND PERHAPS HAIL WITH
   ANY SUSTAINED STORMS THAT DO FORM.
   
   ..CORFIDI.. 04/16/2004
   
   ...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 1730Z