SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Thu Nov 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER OHIO VALLEY... ...SUMMARY... Showers and a few thunderstorms may be accompanied by strong wind gusts across parts of the upper Ohio Valley Saturday evening. ...Upper Ohio Valley... An upper ridge over from Ontario/Quebec into the Ohio Valley will break down/shift east across the Northeast through Saturday evening as a deepening shortwave trough moves across the Great Lakes and Midwest. At this occurs, a deepening surface low will pivot eastward across southern Ontario and into New England by early Sunday morning. A trailing cold front will develop southward across the Lower Great Lakes/Ohio Valley and Northeast during the nighttime hours. Ahead of this feature, southerly low-level flow will transport modest boundary-layer moisture northward, with surface dewpoints expected to mainly be in the 50s F. Forecast soundings indicated meager instability may develop (less than 500 J/kg) with cooler temperatures aloft in the 700-500 mb layer. The lower troposphere thermodynamic profiles are somewhat lackluster, with warmer 850-700 mb temperatures noted in both RAP and NAM soundings, resulting in poor lapse rates. Nevertheless, strengthening westerly flow in the lowest 3 km to around 40-50 kt amid meager instability could result in isolated strong gusts for a few hours during the evening before convection weakens with eastward extent into the overnight hours. ...Coastal Southern CA... An upper low offshore the southern CA coast will move inland on Saturday. At the surface, a weak low and associated wind shift will move inland in the 12-18z time period. Forecast soundings indicate very meager surface-based instability will be present. Currently, forecast guidance varies considerably, with RAP forecast soundings showing virtually no surface-based instability compared to NAM forecast soundings showing 100-300 J/kg SBCAPE, with HRRR forecast soundings somewhere in between. Nevertheless, 30-40 kt flow in the 1-3 km layer could result in locally gusty winds, especially in higher elevations through midday, with low-topped convective elements. ..Leitman.. 11/14/2025
