ZCZC SPCSWOMCD ALL ACUS11 KWNS 021558 SPC MCD 021558 INZ000-KYZ000-ILZ000-021830- Mesoscale Discussion 0345 NWS Storm Prediction Center Norman OK 1058 AM CDT Tue Apr 02 2024 Areas affected...Portions of far eastern IL...extreme northern KY...and southern/central IN Concerning...Severe potential...Watch possible Valid 021558Z - 021830Z Probability of Watch Issuance...40 percent SUMMARY...A gradually increasing severe hail threat should exist with slowly intensifying thunderstorms across southern Indiana and vicinity. The damaging wind and tornado threat remain less clear, but some risk may eventually develop this afternoon. Trends will be monitored for possible watch issuance. DISCUSSION...Convection has been gradually increasing in coverage over the past hour or so across southern IN and vicinity. This activity is largely tied to pronounced ascent associated with a very strong southwesterly mid/upper-level jet. Most of these thunderstorms are currently elevated, and located to the north of an outflow boundary related to earlier morning convection now in WV. Still, visible satellite and surface observation trends show attempts at low-level moisture returning northward ahead of these thunderstorms and filtered daytime heating across parts of southern/central IN. While MUCAPE remains weak at the moment, instability and deep-layer shear are both forecast to increase through the afternoon as a northern and southern-stream shortwave trough phase over the Midwest. This should support a threat for supercells capable of producing mainly severe hail initially. The risk for damaging winds and tornadoes this afternoon will be dependent on whether sufficient low-level moistening/warming will occur to support truly surface-based convection. Regardless of this continued uncertainty with instability, the gradually increasing severe threat over the next few hours may eventually prompt watch issuance. ..Gleason/Thompson.. 04/02/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ILN...LMK...IND...PAH...ILX... LAT...LON 37778803 37938850 38648844 39058804 39398743 40148624 40118503 39268486 38738537 37928666 37798721 37778803 NNNN