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ACUS01 KWNS 101942 SWODY1 SPC AC 101940 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Tue Sep 10 2024 Valid 102000Z - 111200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/SOUTHEAST LOUISIANA... ...SUMMARY... Marginal tornado potential may reach coastal areas of Louisiana during the late overnight/early morning hours. ...20z Update... The forecast remains on track and no changes are needed to the D1 Convective Outlook. See previous discussion below for more information. ..Thornton/Gleason.. 09/10/2024 .PREV DISCUSSION... /ISSUED 1122 AM CDT Tue Sep 10 2024/ ...Southern Louisiana Late Tonight/Early Wednesday Morning... The latest NHC forecast indicates Tropical Cyclone Francine will move northeastward over the western Gulf of Mexico tonight through early Wednesday morning. Morning surface observations show a stalled front remains situated over the northern Gulf, with greater low-level moisture (mid/upper 70s surface dewpoints) generally confined near or just off the LA/MS/AL Gulf Coast. As Francine approaches the LA Coast late tonight, this very moist low-level airmass over the northern Gulf should gradually spread inland along parts of the immediate central Gulf Coast, supporting weak boundary-layer instability. As Francine approaches, a corresponding increase in low-level flow and related effective SRH should support some threat for tornadoes with any low-topped supercells in outer rain bands to the east-northeast of the central circulation. Latest guidance continues to suggest that the better tornado potential over land will occur in the Day 2/Wednesday time frame (after 12Z). But, an isolated/marginal tornado threat still remains apparent along parts of the LA Coast for the last few hours of the Day 1 period (08-12Z) early Wednesday morning, where a Marginal Risk has been maintained. $$