SPC AC 061959

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0259 PM CDT Sat Aug 06 2022

   Valid 062000Z - 071200Z

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
   UPPER MISSISSIPPI VALLEY...

   ...SUMMARY...
   A few severe thunderstorms may develop this afternoon and evening
   from the upper Mississippi Valley into the central High Plains.

   ...20Z Update...
   The primary change with this outlook is to extend the Marginal Risk
   slightly westward over central WY, where a couple of strong storms
   will be possible in an area south of the Bighorn Mountains.
   Otherwise, no changes have been made. See the previous discussion
   below for more information.

   ..Dean.. 08/06/2022

   .PREV DISCUSSION... /ISSUED 1115 AM CDT Sat Aug 06 2022/

   ...IA/MN/WI...
   Morning satellite imagery shows a canopy of cloud cover associated
   with a decaying MCS over MN/WI.  The southern edge of clouds extends
   from northwest IA into far southern MN and southwest WI.  Strong
   heating and ample low-level moisture will be present today to the
   south of this axis, with MLCAPE values expected to exceed 3000 J/kg
   with 20-30 knots of deep-layer mean flow.  Most CAM solutions show
   scattered thunderstorms developing in this area by late afternoon,
   with a few supercell and organized multicell structures possible. 
   Mid-level temperatures are quite warm and lapse rates are weak,
   suggesting that the hail risk will be limited.  However, high PW
   values and steep low-level lapse rates will promote damaging wind
   gusts in the stronger cells.  Therefore have added a small SLGT risk
   area to parts of the region.

   ...High Plains...
   Scattered high-based thunderstorms are expected to develop this
   afternoon and evening over the plains of eastern CO/WY and drift
   eastward.  Forecast soundings show that winds aloft are rather
   strong over WY, but thermodynamics will be somewhat marginal. 
   Isolated supercells will be possible with a risk of hail and
   damaging wind gusts, but the forecast coverage of intense storms
   appears to be in line with a MRGL category at this time.  This will
   be re-evaluated at 20z.

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z