FXUS64 KLIX 150552 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 1252 AM CDT Sat Mar 15 2025 ...New AVIATION... .UPDATE... Issued at 508 PM CDT Fri Mar 14 2025 Quick update due to issuance of Tornado Watch 33 until 10 PM CDT for about the northwest quarter of the CWA. That necessitated increasing PoPs for this evening in those areas. RW && .SHORT TERM... (This evening through Saturday night) Issued at 351 PM CDT Fri Mar 14 2025 A strengthening upper level low is crossing the TX/OK Panhandles. That low will continue to swing northeastward across the Central Plains tonight. At the surface, a stout 975mb low is creating a very tight pressure gradient near it. Observations across the Texas Panhandle have been measuring hurricane force wind gusts today! Southerly is drawing moisture northward from the Gulf of America into western LA east TX. That moisture surge will get pushed east into the CWA this evening and tonight while southern stream 300mb jet moves across TX to the CWA. Model soundings around the CWA show some decent upper and mid level cooling. Even though there'll be an inversion in place, directional shear is actually pretty good which may aide convection in being able to capitalize on that elevated instability. Severe hail and/or winds are the greatest threats. Bigger impacts coming this weekend. Confidence continues to increase for the potential of a severe weather outbreak across portions of the Gulf Coast states with a Moderate Risk now in the SPC severe outlook Day 3. Locally, that risk remains the same as so many other potentially higher end SVR events for the CWA...it's a conditional threat. Global model run to run solutions appear to remain rock solid with little change in the larger scale features and locations. That Central Plains upper low will curl up the upper Mississippi Valley tonight. The western portion of upper troughing still looks to dig south to the Rio Grande tonight before tracking east across Texas Saturday. It never really turns negatively tilted because its so broad. The shape of the trough plays a factor into the winds throughout the column locally. Vertical wind shear will be more than ample ranging from 30 to 60 knots based on height but the directional shear is where there'll be more limitation. One concern for a 'bust' shows up in some model soundings. Right around when storms should be really getting going here, there's a veer-back-veer portion of the lower levels. It's subtle, but there. That comes due to the timing and proximity of the base of the trough to the CWA. Not that it will shut down severe storms, just one of those potential reasons for storms not reaching their full potential. Because that's what we have going for the most part with this system...so much potential...whether its instability or shear. Continuing on the wind impacts to svr wx, the south winds become more southwesterly as the trough approaches which then lowers helicity values. While not optimal for increasing tornado potential, not sure how much it'll really matter as values of 150-300 m2/s2 are sufficient. That's especially true with so much instability developing as low level cap erodes and surface temps warm. Some values are 'off the chart', such is having SBCAPE values approaching 3000j/kg with LI's -10ish (per SPC model sounding climatology). Should note that do have some concern that stubborn marine layer will come into play, especially along/south of I-10 in LA and even MS. Some model soundings actually show the MS coast stuck under an inversion the entire event. Surface warming will be critical there for any storms to be surface based. That doesn't seem to be as much of a problem north of I-10 in MS and north of I-12 in LA but will note that weak low level instability could hinder updraft strength of some to all storms. Pre-event light showers and associated cloud cover could be part of that surface temp limitation. In terms of timing, really not much change between model runs which is good for confidence in that portion of the forecast. So generally thinking window of greatest threat is mid morning through mid evening Saturday. Do think there'll be a sharper gradient of Moderate Risk to Marginal Risk that what SPC has/can draw, meaning thinking there'll be a sharp cutoff of severe weather with nothing south of some line. && .LONG TERM... (Sunday through Thursday night) Issued at 351 PM CDT Fri Mar 14 2025 As the trough axis moves across the Mississippi Valley Sunday, will see quite pleasant weather across the region for a few days as high pressure builds in. Highs will be running at to above normal with no rain expected until later on in the week. && .AVIATION... (06Z TAFS) Issued at 1232 AM CDT Sat Mar 15 2025 MVFR to IFR ceilings across all terminals at forecast issuance time. Could see ceilings lower a bit more, but don't expect extremely low conditions developing. Any organized TSRA convection looks like it will mainly occur during the daytime hours, but won't rule out isolated storms entirely at KBTR and KMCB prior to sunrise. Any daytime convection will have the potential to become severe across pretty much all terminals with the main threat ending from west to east by late afternoon or early evening with VFR conditions expected in the wake of the convection. Even without TSRA, winds will be an issue on east-west runway configurations at most fields with sustained southerly winds exceeding 20 knots and gusts above 30 knots through much of the daytime hours. && .MARINE... Issued at 351 PM CDT Fri Mar 14 2025 Stronger winds and higher waves/seas will accompany a system moving through the country this weekend. A deep trough will dive into the deep south while a deepening low swings north through the upper Mississippi Valley Saturday. Expect strong onshore gradient winds as the associated cold front approaches. Small Craft to Gale winds expected and made not changes to those products already out. Will be issuing a small scale Coastal Flood Advisory for the MS coastal counties. Although tide range is a minimum right now, those strong onshore winds will bring water levels to around a foot above normal Saturday. Although winds behind the front should be at/above 20kts, it probably won't be long as very progressive pattern brings post frontal surface ridge to the northern Gulf coast very quickly. MEFFER && .PRELIMINARY POINT TEMPS/POPS... MCB 51 70 40 73 / 0 0 0 0 BTR 53 72 43 75 / 0 0 0 0 ASD 56 75 44 73 / 10 0 0 0 MSY 58 73 50 71 / 0 0 0 0 GPT 56 73 45 71 / 40 0 0 0 PQL 56 77 43 72 / 60 0 0 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...Wind Advisory from 10 AM this morning to 7 PM CDT this evening for LAZ046-056>060-064>070-076>078-080-082-084>090. GM...Small Craft Advisory until 7 AM CDT Sunday for GMZ530-532-534. Small Craft Advisory until 10 AM CDT this morning for GMZ536-538- 550-552-555-557-570-572-575-577. Small Craft Advisory from 7 PM this evening to 7 AM CDT Sunday for GMZ536-538-550-552-555-557-570-572-575-577. Gale Warning from 10 AM this morning to 7 PM CDT this evening for GMZ536-538-550-552-555-557-570-572-575-577. MS...Wind Advisory from 10 AM this morning to 7 PM CDT this evening for MSZ083>088. Coastal Flood Advisory until 1 AM CDT Sunday for MSZ086>088. GM...Small Craft Advisory until 7 AM CDT Sunday for GMZ532-534. Small Craft Advisory until 10 AM CDT this morning for GMZ538-550- 552-555-557-570-572-575-577. Small Craft Advisory from 7 PM this evening to 7 AM CDT Sunday for GMZ538-550-552-555-557-570-572-575-577. Gale Warning from 10 AM this morning to 7 PM CDT this evening for GMZ538-550-552-555-557-570-572-575-577. && $$ SHORT TERM...ME LONG TERM....ME AVIATION/UPDATE...RW MARINE...ME