SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0724 AM CDT Wed Jul 12 2023 Valid 121300Z - 131200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS MORNING AND EARLY AFTERNOON OVER PARTS OF SOUTHERN IOWA...NORTHERN MISSOURI...AND WEST-CENTRAL ILLINOIS.... ...SUMMARY... Severe thunderstorms will be possible across much of Missouri, Illinois, and adjacent portions of the central Plains and Midwest on Wednesday. Damaging winds and large hail should be the main threats, with some potential for significant (75+ mph) severe winds across parts of Iowa, Missouri, Illinois, and vicinity. ...IA/MO/IL early today... A mature, fast-moving bow echo complex is racing across western IA this morning at 50-60 knots. This system has resulted in numerous reports of wind damage across eastern NE, and is likely to maintain organization for a few more hours as it tracks east-southeastward across southern IA, northern MO, and into central IL. The bowing complex should focus along and south of a surface boundary that extends across this same region. CAM solutions differ on longevity of the system, but the potential exists for a rather long-lived wind damage event. Therefore have added a small ENH risk corridor for this system. ...KS/MO/OK this evening... The aforementioned severe MCS will lay down a boundary somewhere across central MO into central KS. Strong heating and ample moisture to the south of this boundary will yield MLCAPE values of 3000-4000 J/kg. Large scale forcing will be weak, but the potential exists for widely scattered thunderstorms along the boundary. Forecast soundings show sufficient winds aloft and steep lapse rates to pose a risk of large hail and damaging wind gusts with any storms that can form. A few CAM solutions suggest activity will grow upscale and track southeastward into northeast OK overnight. ...IN/OH into New England... A surface quasistationary front currently extends from northern IN into NY and New England. Visible satellite imagery shows mostly clear skies along the boundary, which should allow for substantial destabilization and scattered afternoon thunderstorm development. This corridor lies along the southern fringe of stronger westerly flow aloft, with 25-35 knots of deep-layer shear. This may be sufficient for a few strong storms later today capable of gusty/damaging winds. ..Hart/Leitman.. 07/12/2023
