SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0322 AM CDT Fri Apr 11 2025 Valid 131200Z - 141200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... CORRECTED FOR GRAPHIC ...SUMMARY... Severe thunderstorms are not expected on Sunday or Sunday night. ...Upper MS Valley/Great Lakes... A shortwave trough over the northern High Plains on Sunday morning is expected to amplify as it moves east into the northern Upper Midwest. This will maintain a deep surface cyclone from the central Great Plains into the Upper Great Lakes. Guidance has above-average spread across latest runs and poor run-to-run continuity on placement of the cyclone Sunday afternoon. This will be crucial to identifying a mesoscale corridor of surface-based severe threat, given initially poor quality boundary-layer moisture relative to a pronounced EML. The slower guidance with more northern destabilization suggests that low-end severe potential is plausible across a portion of the Upper MS Valley. Otherwise, rounds of elevated convection are anticipated through the period within a broad but persistent low-level warm theta-e advection regime. Buoyancy should remain weak and be a limiting factor for large hail. ...CO/KS... Atop an intensifying surface ridge nosing down the High Plains, a favorably diffluent upper-level flow regime will become prevalent by late afternoon Sunday and persist into Sunday night. This should support a corridor of convection from CO into KS, that becomes increasingly elevated given the undercutting surface front. Guidance has above-average spread on the latitudinal extent of where convection should form, yielding a broad low-probability thunder area in this forecast. ..Grams.. 04/11/2025
