FXUS64 KLIX 290955 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 355 AM CST Sun Jan 29 2023 ...New SHORT TERM, LONG TERM, MARINE... .SHORT TERM... (Today through Monday) Issued at 345 AM CST Sun Jan 29 2023 A very moist southwesterly upper flow continued across the northern Gulf Coast this morning, with several shortwaves moving through that flow from northern Mexico northeastward. High pressure was well to the east, with a developing warm front across the area. Regional radars showed a large area of rain well north of Interstate 20, and another area of showers and thunderstorms developing near and south of Lake Charles. At 3 AM CST, temperatures ranged from around 50 in the Pascagoula area to the lower 60s west of the Mississippi River. Main concern over the next 24 hours will be the threat of heavy rainfall, with a lesser (but not zero) threat of severe weather. Onshore flow has commenced, with dew points already in the 50s across much of the area, and low to mid 60s not very far offshore. Precipitable water values that were near 0.80 inches last evening (00z LIX sounding) will be nearing 1.5 inches by the time we launch our next balloon in the next couple of hours, and will likely top out near 1.7 inches, near our max moving average for late January. Precipitation should spread into the area over the next few hours, with embedded thunderstorms as a vort max moves across the area during the day into the evening. Expect a band of heavy rain to develop across the area, generally to the north of Interstate 10, with much of the rain falling this afternoon and early evening. Widespread 2 to 4 inch rain amounts are certainly possible, with locally higher amounts. Have opted for a Flood Watch for about the northern half of the CWA for today and tonight. Can't rule out heavy rain south of the watch area, including the Mississippi coast and New Orleans areas, but the threat doesn't appear quite as high in those areas. Forecast soundings indicate sufficient buoyancy and shear for at least a few strong storms this afternoon, especially if they can become surface based. Mid level drying should reduce the precipitation threat late tonight into Monday as the vort max exits to the east. However, low level moisture is likely to hold cloud cover across the area through Monday. Model soundings do indicate some potential for fog late tonight and Monday, particularly near the Mississippi coast, and we will keep an eye on that. I guess the good news is that temperatures will be warm over the next couple of days. With the lack of sunshine expected, high temperatures in the mid 70s on Monday per guidance might be a bit ambitious, and have trimmed a bit there. && .LONG TERM... (Monday night through Saturday) Issued at 345 AM CST Sun Jan 29 2023 Frontal boundary becomes stationary across the area for Monday night through Wednesday, but the question is where? Consensus for now is that it remains north of Interstate 10, with some potential that the entire area remains in the warm sector. North of the front, high temperatures are likely to remain in the 50s, while south of the front, lower 70s aren't out of the question. Another weak impulse or two will ride along the front Tuesday/Wednesday, potentially producing a few showers. Fog may also remain a threat near the coast, particularly Monday night and Tuesday. A strong southern stream shortwave will move across the area Thursday and Thursday night. The associated surface low will move near or north of Interstate 10, and depending on whether the warm sector develops inland, there may be a potential for strong to severe storms for portions of the area Thursday afternoon/evening. Trough exits to the east on Friday, finally drying us out for the weekend, with considerably cooler temperatures expected. We might even see some sunshine by then, because for the next 5 days, that is going to be something we won't see much of. Even then, readings will just be close to normal for early February. Not going to stray from the NBM temperatures, as for much of the area, there's not a lot of model spread. Potential for a forecast bust is going to depend on where the front is each day. If there's any significant sunshine, forecast highs probably will need bumped up through Thursday, but right now, that doesn't look likely. && .AVIATION... (06Z TAFS) Issued at 1141 PM CST Sat Jan 28 2023 All terminals are still in VFR status for now but moisture is increasing and cloud bases are starting to lower and by 12-14z will should start to see some MVFR cigs, likely around BTR and MCB as convection should start to slowly move in from the southwest. Cloud bases should be down to around 2k ft in BTR and MCB and continue to lower as convection moves in. Those two and HDC have the highest risk of seeing major impacts with IFR cigs and vsbys due to convection from morning into the area afternoon. There may be a short break for BTR but convection is likely to redevelop or move back in during the late afternoon. MCB may see convection start mid/late morning and possibly be dealing with it through most of the day. Elsewhere initially low clouds will be a problem late morning through the afternoon before seeing cigs lift again and possibly back in VFR. Convection is a little less certain for MSY/NEW/GPT as most of the rain could remain north. /CAB/ && .MARINE... Issued at 345 AM CST Sun Jan 29 2023 Winds are expected to be less of a factor for marine interests the next few days. Thunderstorms will be a concern today, then the potential for sea fog development overnight through midweek. Another round of thunderstorms on Thursday, with winds increasing behind the front Thursday night and Friday, with the potential for Small Craft Advisories. && .PRELIMINARY POINT TEMPS/POPS... MCB 66 58 67 52 / 100 80 20 10 BTR 72 63 72 58 / 100 70 20 10 ASD 72 61 74 59 / 90 70 20 0 MSY 72 63 72 61 / 80 60 20 0 GPT 67 60 70 59 / 90 60 20 0 PQL 71 59 72 58 / 90 60 10 0 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...Flood Watch from 6 AM CST this morning through late tonight for LAZ034>037-039-046>048-071-076-079>086. GM...None. MS...Flood Watch from 6 AM CST this morning through late tonight for MSZ068>071-077. GM...None. && $$ SHORT TERM...RW LONG TERM....RW AVIATION...CAB MARINE...RW