SPC AC 221625
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1125 AM CDT THU APR 22 2004
   
   VALID 221630Z - 231200Z
   
   THERE IS A MDT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM TUL HRO
   50 N LIT HOT DUA 45 E SPS 30 S OKC TUL.
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM LUK
   ZZV PIT AOO 35 SW MRB BKW CSV UOX PBF PRX 45 SE SPS FSI CSM 45 SSW
   GAG GAG 45 NE GAG 30 NW PNC CNU SGF CGI OWB LUK.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 SSW WAL 20 SSE ROA
   25 ENE TYS 35 WSW TCL 20 W JAN 15 S GGG 20 E TPL 40 SSE BWD 35 S SPS
   30 ENE TCC 20 N ABQ 40 ENE GCN 35 W SGU 10 NNW EKO 60 ENE HVR
   ...CONT... 50 N MOT 30 N 81V 35 NNE DGW 50 SE AIA 50 SW HLC 30 NW
   HUT 30 WSW FNB 10 S OTM 35 N LAF 10 S YNG 30 SSE ELM 10 E ALB 10 NNE
   MWN 10 W 3B1 50 WNW CAR.
   
   ...THERE IS A MDT RISK OF SVR TSTMS THIS AFTERNOON AND EVENING OVER
   PARTS OF EASTERN OK AND WESTERN AR...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM WESTERN OK ACROSS THE OH
   VALLEY INTO SOUTHWEST PA...
   
   ...OK/AR/KS/MO...
   BROAD UPPER TROUGH REMAINS OVER THE CENTRAL UNITED STATES
   TODAY...WITH BAND OF FAST WEST-SOUTHWESTERLY MID LEVEL WINDS FROM
   AZ/NM INTO THE OH VALLEY.  LATEST SURFACE ANALYSIS SHOWS SSW-NNE
   ORIENTED COLD FRONT NEARLY STATIONARY OVER CENTRAL OK INTO NORTHWEST
   TX...WITH REMNANT OUTFLOW BOUNDARY FROM OVERNIGHT CONVECTION ACROSS
   SOUTHEAST OK INTO SOUTHERN AR. AMPLE LOW LEVEL MOISTURE IS IN PLACE
   ACROSS THIS REGION...WITH MID 60S DEWPOINTS ACROSS MUCH OF
   CENTRAL/NORTH TX INTO SOUTHERN OK.  MORNING SOUNDINGS SHOWED A
   SUBSTANTIAL MID LEVEL SUBSIDENCE INVERSION...LIKELY DUE TO DEPARTING
   SHORTWAVE TROUGH OVER MO.  ALL MODEL GUIDANCE SUGGESTS THAT THIS
   FEATURE WEAKENS BY AFTERNOON... LEAVING RELATIVELY STEEP LAPSE RATES
   AND A MODERATELY UNSTABLE AIRMASS.  STRONG DAYTIME HEATING SHOULD
   LEAD TO POCKETS OF AFTERNOON ML CAPE OF 1500-2500 J/KG.  MID LEVEL
   HEIGHTS AND TEMPERATURES RISE THROUGH THE AFTERNOON...SUGGESTING
   LIMITED UPPER FORCING. HOWEVER...A WEAK CAP...PRESENCE OF WEAK LOW
   LEVEL BOUNDARIES...AND WARM ADVECTION ON NORTH SIDE OF BOUNDARIES
   ARE EXPECTED TO AID IN THE DEVELOPMENT OF SCATTERED AFTERNOON
   THUNDERSTORMS ACROSS EASTERN OK AND WESTERN AR.  VERTICAL SHEAR
   PROFILES ARE SIMILAR TO YESTERDAY WITH 6KM SHEAR OF 40-50
   KNOTS...INDICATING A FAVORABLE ENVIRONMENT FOR SUPERCELLS.  SIMILAR
   TO YESTERDAY...VERY LARGE HAIL APPEARS TO BE THE MAIN THREAT. 
   HOWEVER...MODEL FORECAST HODOGRAPHS INDICATE THAT LOW LEVEL SHEAR
   PARAMETERS ARE SLIGHTLY STRONGER THAN YESTERDAY ACROSS EASTERN
   OK...MAINTAINING A RISK OF ISOLATED TORNADOES. STORMS SHOULD SPREAD
   EASTWARD THROUGH THE EVENING ACROSS WESTERN/CENTRAL AR...AND DEVELOP
   NORTHWARD INTO PARTS OF SOUTHEAST KS/SOUTHWEST MO.
   
   ...WESTERN TN INTO SOUTHWEST PA...
   LINEAR MCS CURRENTLY OVER WESTERN TN IS TRACKING NORTHEASTWARD INTO
   A REGION OF INCREASING DIURNAL HEATING/DESTABILIZATION.  RELATIVELY
   STRONG LOW LEVEL WINDS AND AT LEAST MARGINAL INSTABILITY MAY HELP
   RE-INTENSIFY THESE STORMS AS THEY TRACK ACROSS THE REMAINDER OF
   TN...SOUTHERN KY...AND EVENTUALLY INTO WV/PA.  ISOLATED DAMAGING
   WINDS APPEAR TO BE THE MAIN THREAT.
   
   ...NERN NM/TX/OK PANHANDLES...
   NORTHERLY LOW LEVEL WINDS ARE TRANSPORTING DRIER AIR INTO THE TX/OK
   PAHANDLES TODAY.  STEEP MID LEVEL LAPSE RATES WILL REMAIN...WITH THE
   RISK OF ISOLATED AFTERNOON/EVENING THUNDERSTORMS  SPREADING FROM
   NORTHEAST NM INTO THE PANHANDLES.  CURRENT INDICATIONS ARE THAT
   ORGANIZED SEVERE STORMS ARE NOT EXPECTED.  EASTERLY LOW LEVEL JET
   STRENGTHENS AFTER DARK IN THIS AREA AS UPPER TROUGH APPROACHES. 
   THIS WILL INCREASE THE RISK OF MORE WIDESPREAD
   SHOWERS/THUNDERSTORMS. HOWEVER...THIS ACTIVITY IS ANTICIPATED TO BE
   LARGELY NON-SEVERE.
   
   ..HART/BANACOS.. 04/22/2004
   
   ...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 2000Z