Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0337 AM CDT Tue Apr 08 2025 Valid 111200Z - 161200Z ...DISCUSSION... On Day 4/Friday, an amplified large-scale trough will move slowly eastward across the Appalachians. Ahead of a related surface low in the lee of the Appalachians, weakly modified boundary-layer moisture will be in place across the coastal Mid-Atlantic states. While instability will be marginal, owing to the limited moisture and poor lapse rates, strong south-southwesterly midlevel flow may support a couple strong storms during the afternoon. The overall severe threat appears too marginal for severe probabilities at this time. By Day 6/Sunday, a midlevel trough will advance eastward across the northern/central Plains, while an elongated downstream surface trough (with embedded surface lows) promotes partially modified Gulf moisture return across the southern/central Plains and MS Valley. Despite multiple surface boundaries across the Plains, current indications are that a strong EML and related capping atop the limited boundary-layer moisture should inhibit surface-based thunderstorm potential. Thereafter, medium-range guidance varies considerably regarding the timing and evolution of the aforementioned midlevel trough and associated warm sector -- limiting confidence in severe-storm potential for Days 7-8/Monday-Tuesday.