SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1023 AM CST Sun Dec 13 2020 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST TEXAS INTO SOUTHWEST LOUISIANA... ...SUMMARY... A few damaging wind gusts and a couple tornadoes are possible across a portion of southeast Texas and southwest Louisiana, this afternoon to early evening. ...Southeast Texas into southwest Louisiana... Late this morning a warm front extends from a weak surface low in southeast TX, eastward to near Palacios TX and into the northwestern Gulf. The front will move north through the day, likely reaching the Houston metro early this afternoon and continuing into the southwest LA coastal area by late afternoon. Rich low-level moisture with upper 60s to 70 F dewpoints reside along and south of the warm front, and will contribute to MLCAPE from 800-1200 J/kg. Numerous showers and scattered thunderstorms are developing across southeast TX within corridor of isentropic ascent north of this boundary. This activity will remain elevated with minimal severe risk. A somewhat greater threat for severe storms should evolve this afternoon. Some CAMs suggest surface-based storms will develop along confluence boundaries just offshore. A couple of these storms might move inland and interact with the warm front where low-level hodographs with 200-400 m2/s2 storm relative helicity and strong effective bulk shear will support potential for supercells capable of producing a tornado or two. Otherwise, additional surface based storms will be possible as the cold front advances southeast and interacts with the moist warm sector. Storms might eventually evolve into linear structures along the cold front this evening as they spread east into LA with a threat for mainly a few strong to damaging wind gusts. The marginal thermodynamic environment with weak lapse rates and widespread low clouds, along with tendency for deeper forcing for ascent to remain north of warm sector, could potentially serve as limiting factors for a more robust severe threat. ..Dial/Moore.. 12/13/2020
There’s more click here.