ZCZC SPCSWOMCD ALL ACUS11 KWNS 122142 SPC MCD 122142 MTZ000-IDZ000-122345- Mesoscale Discussion 0431 NWS Storm Prediction Center Norman OK 0442 PM CDT Fri Apr 12 2024 Areas affected...Idaho into far southwest Montana Concerning...Severe potential...Watch unlikely Valid 122142Z - 122345Z Probability of Watch Issuance...5 percent SUMMARY...Developing thunderstorms across southern Idaho are expected to pose a severe wind and hail risk through the late afternoon hours as they spread northeast into central Idaho and far southwest Montana. Watch issuance is unlikely given the localized nature of the threat and somewhat marginal environment. DISCUSSION...Latest GOES visible and IR imagery show a cluster of steadily deepening cumulus across south-central ID. This is likely in response to a combination of quickly eroding MLCIN and increasing ascent ahead of a mid-level wave approaching from the south/southwest. Deep boundary-layer mixing is limiting buoyancy with MLCAPE values generally between 250-500 J/kg; however, this has resulted in 0-3 km lapse rates between 8-9 C/km, which will support the potential for strong to severe downburst winds with deeper convective cells. This potential will likely be maximized across areas where temperatures have warmed into the mid/upper 70s. 30-40 knot mid-level winds are elongating mid-level hodographs enough to support effective bulk shear values around 30-35 knots. This kinematic environment, combined with steep mid-level lapse rates, may allow for a supercell or two that will pose a severe hail risk (though this scenario is less certain given the modest buoyancy). The marginal nature of the buoyancy field and weak/nebulous forcing for ascent should limit the overall extent of the severe threat as storms spread north/northeast. ..Moore/Thompson.. 04/12/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TFX...PIH...MSO...BOI... LAT...LON 42091474 42131568 42301679 42471699 42911693 45631503 45711423 45631372 45271304 44931268 44571244 44261232 43851245 42141432 42091474 NNNN