SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0953 AM CST Sat Dec 20 2025 Valid 201630Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few lightning flashes may occur today near coastal Washington, and tonight over southern Louisiana. Dry and stable conditions will prevail over most of the CONUS today, precluding thunderstorms. One exception will be over western WA west of the Cascades, where fast onshore flow, orographic lift, and 100-200 J/kg of CAPE will be present. The other area of some risk of lightning will be over southern LA tonight in a weak low-level warm advection regime. In both areas, thunderstorm coverage is anticipated to be sparse and severe risk negligible. ..Hart/Karstens.. 12/20/2025
