SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CDT Wed Oct 22 2025 Valid 221630Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The severe weather risk appears negligible through tonight. ...Synopsis and Discussion... Current satellite imagery shows a pair of cyclones over North America, a more broad cyclone centered over the Great Lakes/southeastern Ontario and another more compact cyclone farther west just off the central/southern CA Coast. Surface analysis reveals a pair of lows associated with the Great Lakes cyclone: an occluded low beneath the primary cyclone over Lake Huron and another triple-point low farther east over the coast of southern ME. Continued northeastward progression of this system, including the coastal ME surface low, will continue to push the warm sector farther offshore, limiting any severe potential. Lightning is still possible within the warm-air advection showers throughout the afternoon, with the highest coverage across Downeast ME. Isolated lightning is also still possible across New England where continued forcing for ascent and cold mid-level temperatures could support deeper updrafts. Isolated lightning flashes are also possible over and in close proximity to the Lower Great Lakes, where warm lake temperatures locally steepen the low-level lapse rates. Farther west, the cyclone off the central/southern CA coast is expected to progress eastward across central CA and far southern NV during the period. Showers and thunderstorms are ongoing ahead of this cyclone from central CA into the Great Basin and AZ. Increasing low to mid-level moisture and decreasing mid-level temperatures downstream of this cyclone will support continued thunderstorms downstream into the Four Corners and western NM. ..Mosier/Weinman.. 10/22/2025
