Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
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877 FXUS64 KLIX 021649 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 1149 AM CDT Thu May 2 2024 ...New UPDATE, AVIATION... .UPDATE... Issued at 1059 AM CDT Thu May 2 2024 Update sent to increase the PoPs across much of the area. CAMs as usual with these scenarios poorly handling how far the rain and storms move east and how fast they tend to as well. Still some LL convergence over the western portions of the CWA while a subtle mid lvl jet works east across the northwestern Gulf and southern LA. Also a small but impressive area of upper lvl diffluence anchored back in southeast TX and through SELA before that completely closes off. Highest SFC based CAPE is across south- central and into SELA while the best ML Cape is right along the coast. Theta E ridge is right along the Atchafalaya. With all of that storms will likely have little problem crossing the Atchafalaya but after that should see a steady decrease in intensity and coverage. Locations northwest of a line from Pierre Part, LA to McComb, MS have the best chance of seeing moderate to some brief heavy rain and possibly a few strong storms. East of that line the potential for rain will decrease. Anticipate most of southwest MS and SELA will see some rain and the occasional lightning strike. Coastal MS has the greatest uncertainty as storms could really struggle to get that far east with possibly only a few light showers. The southshore is also a little uncertain as we do anticipate rain to finally move in around 19Z but it could be light rain but it would also likely stick around for 3-4 hours. There is also a good chance that there would be a few lightning strikes but overall no major impacts are expected outside of light to short periods of moderate rain and a rumble or two of thunder. /CAB/ && .SHORT TERM... (Today through Friday) Issued at 326 AM CDT Thu May 2 2024 A mid-level shortwave trough is ejecting off the southern Rockies this morning which has initiated widespread deep convection across the Southern Great Plains. This convection is providing a thickening cirrus canopy which should mitigate strong radiational cooling sufficient for widespread fog development for much of the area with exception to the Pearl River Basin and coastal MS where skies remain clearer. As such, a dense fog advisory has been issued in these areas for the expectation of patchy dense fog redeveloping around sunrise this morning. We`ll continue to monitor the progress of the convective systems nearing SW LA this hour, but CAM guidance has greatly backed off this convection reaching our areas prior to the afternoon hours. Propagation of these MCSs remains slower than forecast and maintenance of this convection all the way into our areas is less likely now. However, further redevelopment of convection during the day today across east Texas could still provide some rain to particularly northwest areas later in the day. As the shortwave departs the area through the evening hours though it would be less likely to see showers and storms creep further into the area as subsidence begins to suppress maintenance of new convection. As a result, will back down PoPs for areas especially along the coast. Friday rain chances area much healthier areawide with showers and storms gradually spreading over the area in association with a weaker shortwave trough following along within the persistent west-southwesterly flow of this longwave pattern. Impacts from severe weather and excessive rainfall are overall minimal in association with these two rounds of rain chances. && .LONG TERM... (Friday night through Wednesday) Issued at 326 AM CDT Thu May 2 2024 The long term looks rather hot and humid as we move deeper into May. Aside from a few glancing blows from ejecting weak shortwaves provide slight chances of rain in northern areas this weekend, the longwave pattern amplifies once again with a deep west coast trough enhancing mid-level ridging overhead. This will keep us rain free, but still entrenched in persistent southeasterly flow at the surface which will continue to pump gulf moisture through the area. High mid-level temps and muggy overnight conditions will also mean the potential for above normal high temperatures well into the upper 80s to low 90s into next week. While not quite record-breaking for most sites, it will certainly be feeling more like we skipped ahead to June. && .AVIATION... (18Z TAFS) Issued at 1059 AM CDT Thu May 2 2024 Impacts for most terminals are expected over the next 6 to 12 hours but how much is more of a question. Showers and thunderstorms are moving in and trying to push farther east. MCb and BTR will likely see the greatest impacts with MVFR cigs and vsbys expected at times but could even be down to IFR. HDC has the next best chance of seeing impacts while impacts at MSY, NEW, HUM, and ASD should not be as bad. MVFR cigs and vsbys are possible especially if any TSRA moves over those terminals but rain will likely be on the downward trend. /CAB/ && .AVIATION... (12Z TAFS) Issued at 625 AM CDT Thu May 2 2024 IFR to LIFR CIGs are the prevailing impact at most terminals this morning with southeast wind just strong enough to keep more dense fog from settling at the surface. Even so, VIS impacts are evident especially at ASD, MCB, and HDC this morning. CIGs/VIS impacts should gradually improve at all terminals through the morning. BKN skies will be on the increase by midday as remnant convection from a weakening squall line approaches from the west. -RA will become more prevalent at BTR, MCB, and HDC especially in the afternoon. Cannot rule out periods of TS impacts in these areas primarily north of the I-10 corridor. Thereafter, a break in the rain but MVFR to IFR CIGs building back in tonight. && .MARINE... Issued at 326 AM CDT Thu May 2 2024 Surface high pressure centered to our east over Southeast CONUS will keep the coastal waters in persistent southeast winds of around 10 knots through the weekend and into next week. Seas will also be fairly persistent at 1 to 3 feet through the period. Overall, no significant concerns to maritime operations are anticipated through early next week. && .PRELIMINARY POINT TEMPS/POPS... MCB 82 65 78 64 / 70 40 60 20 BTR 84 70 82 68 / 80 40 60 10 ASD 84 69 84 67 / 60 50 30 10 MSY 84 72 84 72 / 60 60 30 10 GPT 81 70 82 69 / 20 20 10 10 PQL 83 68 84 67 / 10 10 10 10 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...TJS LONG TERM....TJS AVIATION...CAB MARINE...TJS