SPC AC 220111
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0811 PM CDT MON JUN 21 2004
   
   VALID 220100Z - 221200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 30 NNW
   JCT 50 SSW LBB 15 ESE TCC 30 NW CAO 50 SSE EHA 35 ESE GAG 15 ENE PNC
   50 NNW SGF 25 NNW HRO 55 S HRO 40 SSE MLC 30 NNE DAL 40 S SEP 30 NNW
   JCT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 SW MRF 20 SW CNM
   ROW 45 NE 4CR SAF 45 NE GUP 30 NNW FLG 15 NE NID 40 NNE MER 50 WNW
   TVL 55 SE ELY 15 ESE CNY 10 NW ASE 50 SSW DGW 10 E AIA 35 SW HLC SLN
   25 S IRK 45 WSW RFD 30 ESE RHI 15 ENE MQT ...CONT... 30 NNW SYR 20
   WSW PSB 15 ENE ROA 20 ENE ILM ...CONT... 40 SW GLS 60 NNE VCT 20 N
   COT 60 WSW COT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 SSE HUL 55 WNW
   3B1.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 65 SW TUS 25 N TUS 10
   E SAD SVC 40 SE DMN.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS FAR NERN NM EWD ACROSS
   SRN  PLAINS TO OZARK REGION...
   
   ...EXTREME NERN NM EWD ACROSS SRN PLAINS TO OZARK REGION...
   LONG WAVE TROUGH EXTENDING FROM ONTARIO SWWD TO THE GREAT BASIN WILL
   CONTINUE TO MOVE SEWD OVERNIGHT.  WV IMAGERY SHOWS A STRONG SHORT
   WAVE TROUGH MOVING SEWD ACROSS CO...AND A SECOND SOMEWHAT WEAKER
   SHORT WAVE TROUGH EMANATING FROM THE SRN STREAM FLOW OVER THE HIGH
   PLAINS OF SERN CO/NERN NM.  BOTH OF THESE FEATURES WILL TRACK ESEWD
   ACROSS THE SRN PLAINS WITH LARGE SCALE ASCENT SPREADING ACROSS THIS
   AREA TO SUPPORT THUNDERSTORM DEVELOPMENT THROUGH THE FORECAST
   PERIOD.  
   
   AT 00Z...SURFACE COLD FRONT ASSOCIATED WITH THE LONG WAVE TROUGH
   EXTENDED FROM ERN UPPER MI SWWD TO NEAR STL TO THE NORTH CENTRAL
   OK/KS BORDER...AND WSWWD TO THE NRN TX PANHANDLE.  ADDITIONAL
   OUTFLOW BOUNDARIES EXTENDED GENERALLY E-W TO NW ACROSS CENTRAL TX TO
   WRN TX/TX PANHANDLE...AND WERE PROVIDING THE FOCI FOR CLUSTERS OF
   STRONG TO ISOLATED SEVERE STORMS ACROSS PORTIONS OF CENTRAL TO WRN
   TX.  THE COLD FRONT WILL MOVE SSE OVERNIGHT...REACHING THE LOWER
   GREAT LAKES TO THE OZARKS AND THE RED RIVER VALLEY BY 12Z TUESDAY.  
   
   
   GREATEST POTENTIAL FOR WIDESPREAD SEVERE STORMS THIS EVENING INTO
   THE OVERNIGHT PERIOD WILL LIKELY BE WITH THE STORMS CURRENTLY
   LOCATED ACROSS FAR NERN NM INTO THE TX PANHANDLE.  THE INTERSECTION
   OF THE COLD FRONT WITH CONVECTIVE OUTFLOW BOUNDARIES IS PROVIDING
   FAVORABLE BACKED LOW-LEVEL FLOW FOR CURVED HODOGRAPHS WITH A THREAT
   OF ISOLATED TORNADOES. A VERY UNSTABLE AIR MASS WITH STRONG DEEP
   LAYER SHEAR WILL CONTINUE TO SUPPORT SUPERCELLS WITH ISOLATED
   TORNADOES... LARGE HAIL AND DAMAGING WINDS DURING THE NEXT 2-4
   HOURS. BOWING SEGMENTS WILL ALSO BE POSSIBLE AS STORM MERGERS
   PRODUCE SUFFICIENT COLD POOLS...WITH A GREATER POTENTIAL FOR A
   FORWARD PROPAGATING MCS ACROSS PORTIONS OF THE TX PANHANDLE/NWRN TX
   INTO SWRN OK OVERNIGHT AS A SLY LLJ NOSING INTO SWRN OK STRENGTHENS
   TO 35-40 KT.  LOW-LEVEL CONVERGENCE ALONG THE COLD FRONT IS SOMEWHAT
   WEAK...BUT SHOULD STILL AID IN ADDITIONAL SCATTERED THUNDERSTORMS AS
   THE FRONT MOVES SSE ACROSS OK AND SRN MO.  AN AXIS OF MODERATE
   INSTABILITY ALONG THE FRONT ATTM COMBINED WITH SUFFICIENT DEEP LAYER
   SHEAR SHOULD SUPPORT ISOLATED TO SCATTERED SEVERE STORMS WITH
   HAIL/DAMAGING WINDS THE PRIMARY THREATS.  THIS ACTIVITY WILL MOVE
   INTO CENTRAL OK TO NRN AR OVERNIGHT...BUT MARGINAL INSTABILITY AT
   THAT TIME...SHOULD LIMIT SEVERE COVERAGE.
   
   ...LOWER MS VALLEY EWD TO SERN STATES...
   A FEW DAMAGING WET MICROBURSTS WILL BE POSSIBLE THROUGH 02-03Z WITH
   AN ORGANIZED LINE OF THUNDERSTORMS...CURRENTLY EXTENDING FROM WEST
   CENTRAL MS TO NWRN LA...MOVING SEWD INTO CENTRAL MS/NRN LA. 
   ADDITIONAL THREAT WILL EXIST AS THESE STORMS MERGE OVER THE SAME
   LOCATION WITH A NWD BAND OF THUNDERSTORMS ASSOCIATED WITH GULF COAST
   SEA BREEZE.  DESPITE SOME STABILIZATION OF THE AIR MASS WITH THE
   LOSS OF DAY TIME HEATING...MODERATE INSTABILITY WILL CONTINUE TO
   SUPPORT STRONG TO ISOLATED SEVERE STORMS FOR THE NEXT FEW HOURS. 
   FOR ADDITIONAL INFORMATION REGARDING SEVERE POTENTIAL AND HEAVY RAIN
   POTENTIAL ACROSS THE LOWER MS VALLEY...PLEASE REFER TO SPC MESOSCALE
   DISCUSSION (SPCSWOMCD) NUMBER 1370.
   
   AIR MASS ACROSS MUCH OF THE SERN STATES HAS BEEN OVERTURNED BY
   ONGOING CLUSTERS OF STORMS OVER MUCH OF GA INTO SC AND SWD ALONG
   MAINLY THE ERN FL PENINSULA.  WEAK SURFACE LOW AND UPPER SHORT WAVE
   ASSOCIATED WITH THIS ACTIVITY SHOULD SUPPORT ADDITIONAL
   THUNDERSTORMS THROUGH MID EVENING...BUT OVERALL COVERAGE IS EXPECTED
   TO DECREASE AFTER SUNSET AS THE BOUNDARY BEGINS TO STABILIZE.
   
   ..PETERS.. 06/22/2004
   
   ...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 0600Z