SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0153 PM CST Sat Dec 14 2024 Valid 142000Z - 151200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20Z Update... The western edge of thunderstorm probabilities have been trimmed in the middle MS Valley vicinity, where additional thunderstorm development appears unlikely behind the strongly forced band of convection shifting eastward -- in tandem with the midlevel shortwave trough. Farther west, thunderstorm probabilities were also removed over portions of the Coastal Range in northern CA. Forecast soundings suggest EL temperatures/instability are no longer supportive of lightning here. For additional details, see the previous discussion below. ..Weinman.. 12/14/2024 .PREV DISCUSSION... /ISSUED 1030 AM CST Sat Dec 14 2024/ ...Coastal California... The Marginal Risk across parts of coastal CA has been removed with this update. The 12Z OAK sounding showed a dearth of boundary-layer instability, and a line of low-topped convection has weakened as it moves inland in tandem with a shortwave trough also tracking quickly eastward. While strong winds will remain possible in the short term given the enhanced low/mid-level flow noted on recent VWPs from KMUX, the lack of appreciable surface-based instability is expected to limit the overall severe threat for the rest of the period. ...East/Southeast Texas... A shortwave trough over the southern/central Plains this morning will continue to eject eastward across the mid MS Valley through tonight. Related surface low over eastern KS is forecast to weaken in this time frame, as high pressure will remain entrenched over the East Coast. A cold front is expected to stall over parts of east to central TX later today. While a favorably moist low-level airmass will be in place ahead of this front, limited large-scale ascent and poor lapse rates aloft should hinder robust updrafts and organized severe potential across east/southeast TX.