Stormchasers.co.uk

SPC Day 1 Outlook Text Only

Click Here for Graphic

   SPC AC 030511
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1211 AM CDT FRI SEP 03 2010
   
   VALID 031200Z - 041200Z
   
   ...NO SVR TSTM AREAS FORECAST...
   
   ...SYNOPSIS...
   PROGRESSIVE NRN-STREAM PATTERN FCST TO CONTINUE ALOFT THROUGH
   PERIOD...LED BY STG SHORTWAVE TROUGH NOW ANALYZED SWD FROM LOW OVER
   NRN MN.  ASSOCIATED MID-UPPER CYCLONE IS FCST TO DEEPEN
   SOMEWHAT...ENLARGE...AND MOVE EWD TO ENEWD ACROSS NRN ONT THROUGH
   PERIOD.  MEANWHILE TRAILING TROUGH SHOULD SHIFT EWD TO POSITION OVER
   LH...CENTRAL OH...AND EXTREME WRN NC BY 4/12Z.  AS THIS
   OCCURS...RELATED STG COLD FRONT -- ANALYZED ATTM FROM WRN LOWER MI
   ACROSS SRN IL...NRN AR...SERN OK...W-CENTRAL TX -- WILL MOVE EWD
   THROUGH OH VALLEY...AND SEWD OVER CENTRAL/SRN APPALACHIANS...LOWER
   MS VALLEY AND S TX.
   
   ...NRN APPALACHIANS TO S TX...
   WIDELY SCATTERED TSTMS IN CLUSTERS AND SMALL BANDS ARE EXPECTED TO
   FORM INVOF FRONTAL ZONE...PRIMARILY DURING AFTERNOON INTO EARLY
   EVENING.  NARROW CORRIDOR OF FAVORABLE MOISTURE/BUOYANCY IS EXPECTED
   TO DEVELOP DURING PERIOD OF STRONGEST HEATING ALONG/AHEAD OF FRONT
   FROM UPPER OH VALLEY REGION SWWD ACROSS LOWER MS VALLEY...WITH
   RELATIVELY WEAK MID-UPPER LEVEL LAPSE RATES LIMITING BOTH DEPTH AND
   MAGNITUDE OF BUOYANCY.  THEREFORE...DURATION OF THUNDER POTENTIAL
   WILL BE RELATIVELY BRIEF IN THAT CORRIDOR.
   
   FARTHER SW ACROSS W GULF COASTAL PLAIN TO RIO GRANDE
   VALLEY...SOMEWHAT STEEPER LAPSE RATES AND STRONGER SFC HEATING AND
   SFC DEW POINTS LOW-MID 70S F WILL BOOST MLCAPE TO 1500-2000 J/KG
   RANGE IN PREFRONTAL AIR MASS.  CONVECTION MAY DEVELOP EITHER IN
   FRONTAL ZONE OR ALONG PREFRONTAL SEA BREEZE/OUTFLOW BOUNDARIES. 
   MAIN LIMITING FACTOR WILL BE LIGHT...ENELY-NELY WINDS AHEAD OF FRONT
   WHICH WILL ACT TO LIMIT BOTH CONVERGENCE AND VERTICAL SHEAR.  WHILE
   A FEW TSTMS MAY PRODUCE STG GUSTS OR SUB-SVR HAIL...SVR POTENTIAL
   ATTM APPEARS TOO WEAK AND CONDITIONAL TO DRAW AREA OF AOA 5%
   UNCONDITIONAL PROBABILITIES.
   
   ..EDWARDS/STOPPKOTTE.. 09/03/2010
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z