SPC AC 211637
   
   DAY 2 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1137 AM CDT SUN AUG 21 2005
   
   VALID 221200Z - 231200Z
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 85 SSW GBN 40 ENE PHX
   20 NE FLG 35 SE SGU 65 N DRA RNO SVE 4LW PDT 30 N 63S ...CONT... 70
   NE ISN 10 ESE Y22 35 ESE GRI TOP TBN 10 SE POF MKL 25 NNE MSL 20 W
   CHA 20 NW AVL HKY 15 NE ORF ...CONT... 25 E MFE 30 WNW VCT 20 ENE
   TPL ABI FST 75 W MRF.
   
   ...NO SVR TSTM AREAS FORECAST...
   
   ...SYNOPSIS...
   AMPLIFICATION OF LARGE-SCALE PATTERN IS FORECAST OVER THE CONUS AND
   SRN CANADA THROUGH THE DAY 2 PERIOD WITH PRIMARY FEATURES BEING
   SLOW-MOVING UPPER LOW OVER SERN CANADA AND THE NERN STATES...AND
   EVOLVING UPPER TROUGH OVER WRN CANADA INTO THE INTERMOUNTAIN W.
   BETWEEN THESE SYSTEMS...SMALLER-SCALE CIRCULATIONS/SHORTWAVE TROUGHS
   CURRENTLY OVER CO AND THE NRN TX PNHDL WILL PROGRESSIVELY WEAKEN
   OVER THE CNTRL HIGH PLAINS MONDAY/MONDAY NIGHT WITHIN BASE OF SW-NE
   ORIENTED RIDGE EXTENDING FROM THE CNTRL PLAINS TO JAMES BAY.
   
   IN THE LOW-LEVELS...QUASI-STATIONARY SYNOPTIC FRONT WILL EXTEND FROM
   THE NC COAST ACROSS THE SERN STATES...LOWER MS VALLEY AND THEN NWWD
   THROUGH THE RED RIVER VALLEY TO DEVELOPING LOW PRESSURE OVER CNTRL
   MT. A COLD FRONT ASSOCIATED WITH EVOLVING WRN CANADA/U.S. TROUGH
   WILL PUSH SEWD THROUGH THE CANADIAN ROCKIES...PACIFIC NW AND INTO
   THE NRN ROCKIES DURING THE PERIOD.
   
   ...KS/OK/N TX...
   A MOIST BOUNDARY-LAYER CHARACTERIZED BY DEWPOINTS IN THE UPPER 60S
   TO LOWER 70S WILL PERSIST INVOF AFOREMENTIONED FRONTAL ZONE. WHEN
   COUPLED WITH DAYTIME HEATING AND MODESTLY STEEP LOW- TO MID-LEVEL
   LAPSE RATES...AFTERNOON AIR MASS IS EXPECTED TO BECOME MODERATELY
   UNSTABLE WITH MLCAPES OF 1500-2500 J/KG. A RELATIVELY WEAK CAP ALONG
   WITH SOME LARGE-SCALE FORCING ASSOCIATED WITH WEAKENING UPPER
   SYSTEMS OVER KS ARE EXPECTED TO CONTRIBUTE TO AN INCREASE IN STORM
   COVERAGE AND INTENSITY INVOF FRONTAL ZONE DURING THE AFTERNOON AND
   EVENING HOURS.
   
   WHILE OVERALL MAGNITUDE OF TROPOSPHERIC WIND FIELDS WILL REMAIN
   MODEST TO WEAK...FORECAST HODOGRAPHS INDICATE STRONG VEERING WITH
   HEIGHT THROUGH THE LOWEST 3 KM AGL WITH EFFECTIVE BULK SHEARS
   APPROACHING 30-35 KTS. GIVEN THIS COMBINATION OF SHEAR AND
   INSTABILITY...POTENTIAL WILL EXIST FOR A FEW SEVERE STORMS CAPABLE
   OF LARGE HAIL AND DAMAGING WINDS. STORMS SHOULD TEND TO WEAKEN
   MONDAY NIGHT AS BOUNDARY-LAYER COOLS AND STABILIZES.
   HOWEVER...SHOULD SEWD-MOVING CLUSTERS OF STORMS ORGANIZE A COLD
   POOL...SOME POTENTIAL FOR DAMAGING WINDS MAY PERSIST INTO THE
   NIGHTTIME HOURS WITH THREAT POSSIBLY EXTENDING SWD INTO N TX.
   
   ...SERN STATES...
   OTHER CLUSTERS OF LOCALLY SEVERE STORMS CAPABLE OF MAINLY DAMAGING
   WINDS MAY ALSO OCCUR ALONG FRONTAL ZONE OVER PORTIONS OF AL...GA AND
   SC. HERE...A VERY MOIST LOW-LEVEL AIR MASS /I.E. DEWPOINTS OF 70-75
   F/ COUPLED WITH DAYTIME HEATING WILL RESULT IN THE DEVELOPMENT OF
   MODERATE TO STRONG INSTABILITY /MLCAPES OF 2000-3500 J/KG/.
   MOREOVER...ELY LOW-LEVEL WINDS ON IMMEDIATE COOL SIDE OF BOUNDARY
   BENEATH VERY SRN FRINGE OF STRONGER MID-LEVEL FLOW ASSOCIATED WITH
   NERN U.S. TROUGH WILL RESULT IN MARGINALLY STRONG VERTICAL SHEAR
   ACROSS NRN EXTENT OF INSTABILITY AXIS.
   
   ..MEAD.. 08/21/2005
   
   ...NOTICE...
   THE STATION RELATIVE POINTS IN THIS PRODUCT ARE NOW AVAILABLE
   SEPARATELY UNDER THE WMO HEADINGS WUUS01 PTSDY1...
   WUUS02 PTSDY2...WUUS03 PTSDY3.  THE INCLUSION OF POINTS
   IN THIS DISCUSSION WILL BE DISCONTINUED AFTER THE 2005
   CONVECTIVE SEASON.  A PUBLIC NOTIFICATION STATEMENT (PNS)
   WILL PROVIDE DETAILS ON THE TRANSITION.
   
   CLICK TO GET WUUS02 PTSDY2 PRODUCT

   NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0800Z