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Aug-29-2003 1300 UTC Day 1 Convective Outlook
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   SPC AC 291227
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0727 AM CDT FRI AUG 29 2003
   
   VALID 291300Z - 301200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 10 E
   EFK 45 SW ALB 35 SSW IPT 20 W LBE 35 ESE MFD 30 SSE DTW
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 SSE CRP 15 SE SAT
   35 S JCT 30 SSE DRT ...CONT... 55 ESE YUM 35 S EED 55 ESE TPH 35 N
   U31 75 SW BOI 65 NW 27U 30 SE 3DU 25 ESE LWT 30 E MLS 25 E Y22 40
   NNW ATY 20 S ATY 50 SSE PHP IML 35 SSE HSI 30 WNW BRL 55 SE OSC
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM NERN OH TO NRN
   VT...INCLUDING NRN PA AND MUCH OF UPSTATE NY...
   
   ...NERN U.S...
   
   STRONG SHORTWAVE TROUGH OVER ONTARIO WILL ONLY BRUSH PORTIONS OF THE
   NERN U.S. TODAY WITH ANY APPRECIABLE HEIGHT FALLS EXPECTED TO REMAIN
   NORTH OF THE U.S. BORDER.  EVEN SO...IT APPEARS DEEP LAYER SHEAR
   WILL INCREASE ACROSS THE SLIGHT RISK AREA BECOMING FAVORABLE FOR THE
   SUSTAINMENT AND ORGANIZATION OF DEEP CONVECTION.
   
   AS UPPER TROUGH APPROACHES QUEBEC...WARM FRONT IN PLACE OVER NY WILL
   RETURN QUICKLY NEWD ALLOWING MUCH HIGHER THETA-E AIRMASS TO SPREAD
   ACROSS THE UPPER OH VALLEY INTO NY...ALONG WITH GREATER SFC-BASED
   INSTABILITY...ON THE ORDER OF 1500 J/KG.  THUNDERSTORMS HAVE ALREADY
   DEVELOPED ALONG COLD FRONT ACROSS SERN ONTARIO...AND THIS BOUNDARY
   SHOULD ONLY BECOME MORE CONVECTIVELY ACTIVE AS BOUNDARY LAYER WARMS.
    ISOLATED SUPERCELLS ARE POSSIBLE BUT THE MORE LIKELY MODE IS FOR
   MULTIPLE FORCED LINES OF THUNDERSTORMS TO SWEEP ACROSS THE AREA AS
   COLD FRONT ADVANCES EWD.  DAMAGING WINDS SHOULD BE THE PRIMARY
   SEVERE THREAT AS LAPSE RATES APPEAR TOO WEAK TO GENERATE SIGNIFICANT
   HAIL.
   
   ...LOWER OH VALLEY TO NWRN TX...
   
   FARTHER SW ALONG BOUNDARY FROM IND TO NWRN TX...THICK BAND OF CLOUDS
   AND PRECIPITATION HAVE PERSISTED MOST OF THE NIGHT AND CONTINUE TO
   PROPAGATE SEWD OVERTURNING WHAT MARGINAL INSTABILITY EXISTS. 12Z
   SOUNDINGS ALONG THIS ZONE EXHIBIT DEEP MOIST ADIABATIC LAPSE RATES
   WITH HIGH PW VALUES APPROACHING 2 IN MANY PLACES.  IN ALL
   LIKELIHOOD...BOUNDARY LAYER WILL STRUGGLE TO DESTABILIZE
   SIGNIFICANTLY...EXPECT FOR PORTIONS OF NWRN TX/SERN OK WHERE DEEP
   LAYER FLOW IS SO WEAK PULSE-TYPE STORMS WILL BE THE DOMINANT MODE. 
   ORGANIZED SEVERE DOES NOT APPEAR PROBABLE GIVEN THE WEAK SHEAR AND
   THERMODYNAMIC PROFILES OBSERVED.
   
   ..DARROW/BANACOS.. 08/29/2003
   
   ...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 1630Z
        
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