ZCZC SPCSWOMCD ALL ACUS11 KWNS 052244 SPC MCD 052244 IAZ000-MNZ000-SDZ000-NEZ000-060045- Mesoscale Discussion 1157 NWS Storm Prediction Center Norman OK 0544 PM CDT Mon Jul 05 2021 Areas affected...Far southeast South Dakota into northwest Iowa Concerning...Severe potential...Watch unlikely Valid 052244Z - 060045Z Probability of Watch Issuance...5 percent SUMMARY...Thunderstorms may develop along a stationary boundary across northwest to north-central Iowa prior to sunset, though the potential for additional storms is uncertain. However, storms that do form could pose a brief severe hail risk. DISCUSSION...Recent satellite imagery continues to show a generally shallow cumulus field along a stationary boundary draped across northern IA. Despite the meager appearance of the cumulus field, new convection has been intensifying at the intersection of the boundary and convective outflow from an upstream cluster of storms across southeast SD. Although lift is locally augmented at this intersection, objective analysis trends over the past hour suggest convergence may be gradually increasing along the stationary boundary across northwest IA, and RAP forecast soundings hint that low-level parcels are near their convective temperatures. This suggests that an isolated thunderstorm or two could develop either 1) along the stationary boundary (likely prior to sunset and the onset of boundary-layer stabilization) or 2) along the convective outflow as it gradually pushes east through the evening hours. Confidence in either solution is somewhat low, and storm chances decrease with eastward extent due to weaker convergence/implied ascent. Given moderate instability in place (upwards of 3000 J/kg MLCAPE), any storms that do form may initially be capable of producing severe hail, though the lack of sufficient deep-layer shear will limit the duration of this threat. Given the lack of confidence in storm coverage and low potential for robust storm organization, a watch is not expected. ..Moore/Hart.. 07/05/2021 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DMX...FSD...OAX... LAT...LON 43519755 43799713 43489638 43379539 43369469 43279407 43099342 42579342 42389401 42569502 42639637 42699702 42889763 43099788 43519755 NNNN