SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CST Tue Dec 23 2025 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF COASTAL CALIFORNIA AND THE CENTRAL VALLEY... ...SUMMARY... Thunderstorms with marginally severe wind gusts, small hail and potentially a brief tornado will be possible from Wednesday into Wednesday night along parts of the California coast, and inland across the San Joaquin Valley. ...California Coast... West of an imposing upper ridge building over the central US, deep troughing will intensify Wednesday and Wednesday night over the eastern Pacific. Several embedded disturbances will track onshore over parts of the West Coast. Strong ascent and strengthening onshore flow will aid in modest destabilization, first near the southern CA coast/LA Basin and eventually farther north and inland. A band of storms will likely be ongoing over southern CA and adjacent waters early Wednesday morning. Strong flow aloft (1km AGL wind 50+ kt) may mix to the surface supporting strong gusts and the potential for a brief tornado. A second more potent shortwave and surface low (sub 985 mb) will intensify and move near the central/northern CA Coast into early Thursday. A broken, low-topped band of storms along the advancing cold front may eventually move onshore overnight with a risk for occasional strong gusts. ...San Joaquin Valley... Across central CA, cold mid-level temperatures (-24 to -27 C), strong height falls and the left exit of a 100+ kt mid-level jet will overspread 50s F surface dewpoints across the northern and central San Joaquin Valley Wednesday afternoon and evening. Model soundings show modest MUCAPE (max around 500 J/kg) amid veering wind profiles and enlarged hodographs. Despite the limited buoyancy, a few semi-organized supercells are possible. Damaging gusts, hail and a brief tornado are possible with the strongest storms before convection gradually moves eastward into the higher terrain and weakens. ..Lyons.. 12/23/2025
