SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0546 AM CST Sun Dec 06 2020 Valid 061300Z - 071200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SOUTH FL AND THE KEYS... ...SUMMARY... Locally damaging winds and a brief tornado are possible across south Florida and the Keys late tonight to early tomorrow morning. ...South FL and the Keys... A shortwave trough over east TX will phase with a trough ejecting east from IL as an upstream impulse digs south from northwest Ontario. This evolution will aid in initial weak cyclogenesis over the northeast Gulf tonight, followed by secondary cyclogenesis over the Gulf Stream east of the Carolinas tomorrow morning. Poor tropospheric lapse rates will be a limiting factor with buoyancy likely to remain weak despite 14-16 g/kg mean-mixing ratios. Nevertheless, consensus of guidance suggests a belt of strengthening 850-mb flow will become centered across south FL and the Keys by 09-12Z. This should occur in tandem with convective clusters across the eastern Gulf spreading towards the region late in the period, supporting a low probability damaging wind and tornado threat. ..Grams.. 12/06/2020
There’s more click here.