SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0648 AM CST Sat Jan 16 2021 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Very isolated lightning flashes may persist across a portion of coastal New England into this afternoon. ...Northeast... An amplified upper trough centered on the Upper OH Valley will shift northeast into New England by tonight. Attendant mid-level cold core should progress across the central Appalachians into the Mid-Atlantic States later this afternoon. Abundant cloud coverage and ongoing snow showers will slow boundary-layer heating within the cold core region. This will likely limit SBCAPE to at or below 100 J/kg despite steep 0-3 km lapse rates sampled by 12Z ILN and BNA soundings. While a couple lightning flashes are plausible midday into the afternoon, the overall setup appears unlikely to warrant a 10 percent or greater probability of thunder. Downstream, much stronger forcing for ascent within the warm conveyor has supported sporadic lightning predominantly south of the southern New England coast, but a few flashes have been detected in eastern MA over the past 90 minutes. Scant elevated buoyancy within the apex of the low-level moisture plume may be sufficient for very isolated lightning flashes into early to mid afternoon. But this risk should diminish over Downeast ME as the warm conveyor becomes increasingly divorced from the warmer North Atlantic waters of the Gulf Stream. ..Grams.. 01/16/2021
There’s more click here.