SPC AC 311930

   Day 3 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0230 PM CDT Mon Mar 31 2025

   Valid 021200Z - 031200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM THE GREAT
   LAKES INTO PARTS OF THE MID MS VALLEY AND ARKLATEX...

   ...SUMMARY...
   An outbreak of severe storms is possible Wednesday and Wednesday
   night across the Lower Great Lakes, Mid Mississippi Valley, and the
   ArkLaTex. Severe wind gusts, very large hail, and significant
   tornadoes are expected.

   ...Synopsis...
   No major changes have been made to the outlook, aside from
   tightening the gradient in severe probabilities across the southeast
   portion of the threat area. An outbreak of severe storms still
   appears possible, with a threat of significant tornadoes, widespread
   damaging winds, and hail. An upgrade remains very possible in
   subsequent outlooks for some portion of the Enhanced Risk area. 

   A strong mid/upper-level trough and attendant surface cyclone will
   move northeastward across the upper Midwest and Great Lakes regions
   on Wednesday, as a powerful jet (80-120 kt at 500 mb) overspreads
   parts of Midwest and mid/upper MS Valleys. A cold front attendant to
   the cyclone will move eastward, with widespread strong to severe
   storms expected along/ahead of the front.  

   ...Midwest to the Great Lakes and Ohio Valley...
   One or more clusters of storms will likely be ongoing Wednesday
   morning across parts of IA/MO/IL. An isolated severe threat may
   persist through the morning, with some intensification and/or
   redevelopment as convection spreads east-northeast in conjunction
   with the surface cyclone and cold front. The northward extent of
   substantial destabilization remains in question due to the influence
   of early convection, but very strong low-level and deep-layer shear
   will support a threat of damaging winds and tornadoes if
   surface-based storms can be sustained into the Great Lakes region
   during the afternoon and evening. 

   ...Mid Mississippi Valley and vicinity...
   Substantial low-level moistening is expected from the ArkLaTex into
   the MS/OH Valleys during the day on Wednesday, aided by a
   persistently strong (40-60 kt) low-level jet. While the primary
   surface cyclone will become increasingly removed from this region
   with time, favorable low-level moisture transport and upper-level
   difluence will support widespread thunderstorms along/ahead of the
   front from IL southwestward into the ArkLaTex region. 

   The environment will be quite favorable for tornadic supercells,
   with rich low-level moisture, very strong low-level and deep-layer
   shear, and at least moderate instability. There will be some
   potential for storm interactions and upscale growth given the
   likelihood of persistent deep convection within the prefrontal
   corridor, but significant tornadoes will be possible if any
   supercells can be sustained through the afternoon and evening.
   Otherwise, scattered to widespread damaging winds and large to very
   large hail will also be possible along/ahead of the front. 

   With lingering uncertainty regarding the influence of early-day
   storms and potential for long-lived supercells within a corridor of
   widespread convection, no upgrade was made with this outlook.
   However, it remains very possible that a categorical upgrade will
   eventually be needed for some part of the region. 

   ...Southern Plains into the ArkLaTex overnight...
   A broad mid/upper-level trough will remain in place across western
   CONUS through the period, and a low-amplitude shortwave may emerge
   from this trough late Wednesday night. The cold front will tend to
   slow down or stall across the southern Plains into the ArkLaTex,
   with renewed low-level jet development forecast into early Thursday
   morning. Redevelopment of storms late Wednesday night into Thursday
   morning is expected near and north of the front, with moderate to
   strong buoyancy and strong deep-layer shear still supportive of
   organized convection. A threat for hail and damaging wind gusts will
   accompany the overnight storms, and some tornado threat could evolve
   with storms in the vicinity of the surface boundary.

   ..Dean.. 03/31/2025

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   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z