SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025