SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Mon Jun 16 2025 Valid 161630Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PARTS OF NEBRASKA...AND PARTS OF MINNESOTA.... ...SUMMARY... Scattered severe thunderstorms capable of producing severe/damaging gusts, large to very large hail, and a few tornadoes are forecast today across parts of the northern/central Plains into the Upper Mississippi Valley. ...MN/IA... Morning water vapor imagery shows a shortwave trough over the eastern Dakotas. As this trough moves eastward this afternoon, a surface low will deepen over central MN with a trailing cold front sweeping across the state. Morning convection is getting out of the way, which should allow several hours of strong heating/destabilization. Afternoon MLCAPE values of 3000+ J/kg are expected, with little inhibition. This should lead to rapid thunderstorm development by mid-afternoon near the surface low, with at least widely scattered development southward along the cold front into northern IA. Low-level winds are somewhat veered but strong. This coupled with favorable westerly flow aloft should promote a few supercells capable of large hail and damaging winds. A tornado or two is also possible. ...NE/KS... The aforementioned cold front will sag southward into northern NE by early evening. A strong southerly low-level jet south of the front, along with steep mid-level lapse rates and large CAPE, will promote the development of scattered intense storms along the front. Supercells capable of very large hail and damaging winds are expected, along with perhaps a tornado. Congealing outflows from high-based convection are expected to move into the region during the mid-evening from the west, resulting in upscale convective growth and an increasing risk of damaging winds. ...MS/AL... Strong heating is occurring today across much of MS and western AL, where dewpoints are in the mid 70s. Clusters of thunderstorms are forming over LA, which are expected to propagate northeastward across the region through the day. Steep low-level lapse rates, large CAPE, and relatively strong ambient low-level wind fields will pose some of risk of gusty/damaging wind gusts in the strongest cells today. ..Hart/Wendt.. 06/16/2025