Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
030 FXUS64 KLIX 041145 AAA AFDLIX Area Forecast Discussion...UPDATED National Weather Service New Orleans LA 645 AM CDT Fri Sep 4 2026 ...NEW AVIATION... .KEY MESSAGES... Updated at 642 AM CDT Fri Sep 4 2026 - Numerous showers and storms are forecast through this weekend. While the overall severe weather threat will be low, one or two storms could become strong to severe wind gusts, frequent lightning and periods of heavy rain. - Above normal temperatures expected most of the 7-Day forecast period. Afternoon heat indices will generally range from 100 to 107 degrees. && .SHORT TERM... (Now through Sunday) Issued at 312 AM CDT Fri Sep 4 2026 A broad upper level high pressure system is currently centered over the south-central US with upper lows on its northeastern and northwestern flanks. The ridge will amplify and expand north well into central Canada today. Closer in to the local area, an easterly wave in the northern Gulf will be moving continue tracking west. This feature should provide a favorable environment for convection, and with increasing low-level convergence and abundant moisture, promote numerous shower and storm development. Radar imagery early this morning is already showing increasing shower activity near coastal areas. Look for this to spread inland through the morning and afternoon hours. The latest forecast calls a range of 70 to 90 percent, with greatest chances along coastal areas of LA and MS. Did go above NMB/WPC POPs over coastal LA as well as BTR and NEW metros as lower guidance values looked unrealistic and not meteorologically driven. The greater cloud cover and earlier convection across the region should keep highs mainly in the upper 80s to around 90, although areas that avoid storms longer could still reach the lower 90s. Model soundings remain fairly saturated throughout the profile, so widespread damaging winds are not as likely as today. However, any localized midlevel drying combined with stronger pre-convective heating could increase DCAPE enough to support an isolated strong to marginally severe downburst. Over the weekend, the upper level ridge becomes centered farther west over the southern Plains while the local area remains along its southeastern periphery. At the same time, troughing begins to deepen across the eastern CONUS, with the resulting weakness aloft continuing to support daily convection. Saturday should remain fairly active given the lingering deep moisture, with scattered to numerous mainly afternoon storms developing along mesoscale boundaries. Highs will generally remain in the lower to middle 90s with heat indices again around 100 to 107 degrees before convection provides some relief. As the ridge shifts farther west and flow aloft becomes somewhat more northerly, forecast profiles may begin to show slightly more midlevel drying compared to earlier in the period. If this occurs, increasing DCAPE and a better-defined inverted-V structure could modestly increase the potential for isolated strong downbursts, particularly where storms develop after prolonged heating. && .LONG TERM... (Monday through Thursday) Issued at 312 AM CDT Fri Sep 4 2026 On Labor Day, the forecast area will remain positioned between a broad upper level ridge centered over the southern Rockies and a longwave trough across the eastern seaboard. This will place the region beneath a deep mid to upper level north-northeasterly flow pattern. A dissipating stalled frontal boundary over the area on Monday will serve as the focus for convective development. PWATS will be near seasonal averages and moisture will converge along the front where weak convergence will support updraft development. PoP will peak around 50 to 60 percent to reflect the convective risk associated with the stalled front over the area. Temperatures will also be slightly warmer than average in the low to mid 90s as the drier air and later convective initiation allows for more daytime warming to occur. Heat index values will likely exceed advisory levels for Labor Day. Anyone participating in large outdoor events and activities should take extra heat precautions. Tuesday through Thursday will see warming and drying air aloft begin to feed into the area as a ridge expands eastward. PWATS will fall below average and any convective development will be more isolated to widely scattered. Any convective activity should also be more confined to the seabreeze. The one concern primary concern each day will be the increased potential for some damaging downburst wind events to occur with the deepest updrafts that climb above 30k feet. The drier air in the mid-levels could easily entrain into any deeper updrafts leading to evaporative cooling and downburst development. This is supported by steep lapse rates over 8.0C/km below 850mb and DCAPE of around 1200 J/KG Tuesday afternoon. Beyond the threat for a few damaging wind events, temperatures will remain very warm with highs climbing back into the low to mid 90s. However, the drier air aloft mixing down into the boundary layer should keep heat index readings just below advisory levels as we move through the week. && .AVIATION... (12Z TAFS) Issued at 645 AM CDT Fri Sep 4 2026 Convection is ongoing for NEW and MSY. Soon showers and storms will start to impact HDC for a an hour or so this morning. Convection will likely clear in the next hour or two, but more afternoon convection will be possible leading to MVFR or lower CIGs/VIS respectively. Winds will generally be light, but will be gusty and more erratic in and around convection. Tonight any convection will become more isolated. Need to watch for fog especially terminals the receive rainfall this afternoon and evening. (Frye) && .MARINE... Issued at 312 AM CDT Fri Sep 4 2026 The pressure gradient is expected to be fairly weak the next several days, lending to quite benign marine conditions over marine areas. This pattern will maintain winds generally 10 knots or less through the weekend with seas around 1 to 2 feet. The main potential impacts comes from daily rounds of isolated to scattered thunderstorms. Those will have the potential to produce locally higher winds and waves. && .LIX WATCHES/WARNINGS/ADVISORIES... LA...None. GM...None. MS...None. GM...None. && $$ SHORT TERM...ME LONG TERM....ME AVIATION...RDF MARINE...ME