SPC AC 090912

   Day 1 Convective Outlook CORR 1
   NWS Storm Prediction Center Norman OK
   0412 AM CDT Tue Jun 09 2020

   Valid 091200Z - 101200Z

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
   THE CENTRAL PLAINS/MISSOURI VALLEY AND MID MISSISSIPPI/OHIO VALLEY
   REGION...

   CORRECTED FOR TEXT

   ...SUMMARY...
   Scattered severe thunderstorms, with hail, wind, and a few
   tornadoes, are expected from parts of the central Plains to the
   Missouri Valley. Other isolated severe storms may be noted across
   the mid Mississippi and Ohio Valleys. A few tornadoes and some wind
   damage are possible.

   ...Central Plains/Missouri Valley...

   Strong short-wave trough, currently located over CO/NM, is forecast
   to shift into KS later today with intense 12hr mid-level height
   falls expected to spread across the central Plains. This feature
   will force a pronounced surface low into central KS by 18z and
   substantial surface heating ahead of the front should contribute to
   strong buoyancy arcing from southeastern KS into north-central KS
   just north of the surface low. Forecast soundings exhibit MLCAPE
   values in excess of 3000 J/kg across this region with minimal
   inhibition by early afternoon. Latest thinking is scattered
   supercells should develop immediately ahead of the surface low,
   within a focused exit region of 80kt+ 500mb jet. Convection is
   expected to initiate by 19-20z then spread east along the KS/NE
   border region as strong large-scale forcing for ascent spreads
   toward the MO Valley. NAM forecast soundings strongly favor
   supercells with wind profiles supportive of tornadoes. Some
   consideration was given to increasing tornado probs along the NE/KS
   border where favorably backed low-level inflow will likely enhance
   shear. Otherwise, very large hail and damaging winds appear possible
   with these afternoon storms.

   ...Remnants of Cristobal...

   Remnants of Cristobal are advancing north across the mid-South
   region into MO early this morning. Circulation center should track
   across eastern MO toward southwestern WI by early evening. While
   poor lapse rates will necessarily limit buoyancy across the mid
   MS/OH Valleys, strong LLJ should translate across IL toward southern
   Lake MI by 10/00z. Showers/thunderstorms that form within this flow
   regime may exhibit low-level rotation and a few tornadoes are
   possible with the most robust updrafts.

   ...South TX...

   Pre-frontal wind shift will surge across TX to near the Balcones
   Escarpment by 18z, then settle into south-central TX during the
   late-evening hours. Strong surface heating near the boundary should
   weaken the cap and a few thunderstorms may ultimately develop along
   the wind shift. With temperatures warming to near 100F, high-based
   convection could generate isolated severe wind gusts and hail.
   Operational NAM suggests frontal forcing during the overnight hours
   will contribute to additional storms that would propagate toward
   deep-south TX.

   ..Darrow/Nauslar.. 06/09/2020

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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