SPC AC 242007

   Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0307 PM CDT Thu Jun 24 2021

   Valid 242000Z - 251200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS NORTHERN
   KS...NORTHERN MO...AND FAR SOUTHEAST NE...

   ...SUMMARY...
   A corridor of severe weather (including destructive hail, severe
   wind and a few tornadoes) is possible late this afternoon into
   tonight from northern Kansas into northern Missouri and far
   southeast Nebraska.

   ...20Z Update...
   The following changes have been made based on the latest
   observations and short-term guidance. 

   1. Removed the Slight Risk across portions of northern IL into
   southern/central WI, where stabilizing effects of widespread
   cloudiness and precipitation have reduced the threat to some extent.

   2. Expanded the Marginal Risk slightly northward across northern WI,
   where more substantial heating and destabilization has occurred in
   advance of a cold front.

   3. Trimmed the northern edge of the Enhanced Risk across far
   southern NE, as it appears the most substantial development later
   this afternoon/evening will occur to the south and east of the
   trimmed area. 

   Otherwise, intense thunderstorm development is expected across
   northern KS into northern MO and far southeast NE late this
   afternoon and evening. See MCD 1076 and the previous discussion
   below for more information.

   ..Dean.. 06/24/2021

   .PREV DISCUSSION... /ISSUED 1128 AM CDT Thu Jun 24 2021/

   ...Northeast KS into northwest MO...
   A large MCS is moving slowly eastward this morning across northern
   MO into central IL.  The outflow boundary from this system extends
   from west-central KS into central MO.  Very moist and unstable air
   is present to the south of the boundary, with dewpoints in the mid
   70s and potential MLCAPE values over 4000 J/kg later today.  This
   boundary is expected to lift northward this afternoon to roughly the
   I-70 corridor of northeast KS (although the ongoing convection over
   southeast KS lends some uncertainty to afternoon boundary position).
    Scattered supercell storms are expected to develop in vicinity of
   the boundary by late afternoon, tracking eastward into northwest MO
   this evening.  Model guidance suggests that the low-level jet will
   strengthen considerably during the evening, with forecast soundings
   showing very favorable hodographs for supercells capable of very
   large hail, damaging winds, and a few tornadoes.  Considered adding
   at 10% tornado threat area, but will defer to 20z update when
   eventual position of the boundary is better defined.

   Storms are expected to congeal into a bowing complex through the
   evening, affecting portions of north-central MO with the threat of
   rather widespread damaging winds and hail.

   ...Western and Central KS...
   A well-defined surface low is forecast to become established over
   central KS today, with considerable wrap-around low-level moisture
   in place over much of western and northern KS.  This will likely
   lead to scattered intense thunderstorms later today.  Very large
   hail and damaging wind gusts will be the main threats.  Have
   adjusted the orientation of the SLGT/ENH areas to better reflect the
   surface low position, and where CAM consensus shows highest
   confidence in storm coverage.

   ...Eastern NM/TX Panhandle...
   A deeply mixed boundary layer will develop this afternoon over much
   of eastern NM and the TX Panhandle, where scattered high-based
   thunderstorms are forecast.  Locally gusty/damaging wind gusts are
   possible in the strongest cores.

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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