


Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA
Issued by NWS New Orleans/Baton Rouge, LA
277 FXUS64 KLIX 181829 AFDLIX Area Forecast Discussion National Weather Service New Orleans LA 129 PM CDT Mon Aug 18 2025 .UPDATE... Issued at 127 PM CDT Mon Aug 18 2025 Retransmitting earlier product which did not send properly. && .SHORT TERM... (This afternoon through Tuesday night) Issued at 1244 PM CDT Mon Aug 18 2025 Not a whole lot to discuss that hasn`t already been said in the last few days. Local area will remain loosely under the influence of high pressure aloft which will result in somewhat delayed onset of convective initiation of scattered afternoon showers and thunderstorms. Afternoon temperatures are forecast to rise into the mid to upper 90s, with maximum heat index values forecast to peak in the 106-109 degree range most places. Have seen a few mesonet sites reach criteria today, but lower dewpoints have started to mix down from aloft and that should help bring the heat index down as well. Between the drier air mixing down and the fact that we`re starting to see convection popping up, will not issue a short- fused heat advisory for the remainder of this afternoon. However, with similar conditions expected tomorrow, will go ahead with a heat advisory from 10a-7p tomorrow for most of the forecast area. The one good thing about this set up is that overnight lows have generally been in the mid 70s aside from areas along the immediate lakeshore and coast of SE LA, and that will provide overnight relief from the heat, helping limit the cumulative effects of heat impacts as well. && .LONG TERM... (Wednesday through Sunday) Issued at 1244 PM CDT Mon Aug 18 2025 Overall pattern will remain generally unchanged through Wednesday as the upper high gradually retreats westward in response to a trough moving into New England and hurricane Erin recurving northward over the western Atlantic. This will begin the transition to a more active pattern for the second half of the work week. Some question regarding exactly how much coverage we`ll see on Wednesday. With the ridge`s influence waning, should see at least a slight increase in coverage, but likely still in the scattered category. By Thursday and into Friday, the high should be solidly centered near the four corners region with an overall weakness or even weak troughing in the upper levels across the local area allowing for more typical summertime coverage of scattered to numerous showers and storms each afternoon. The increase in convective coverage should also result in a slight decrease in afternoon temperatures, with highs falling a couple degrees back into the low 90s most places. Going into the weekend, biggest question continues to focus on exactly how far south a weak frontal boundary will move before stalling and dissipating. Ensemble guidance has been fairly consistent with the front stalling somewhere near the local area, and this will enhance rain chances by providing a convective focus. Moisture pooling ahead of the front will also raise precipitable water to over 2 inches across much of the area, with some model soundings indicating values of around or just over 2.2 inches across areas just ahead of the front. This would be around or just above the 90th percentile for this time of year, and suggests potential for efficient rainfall processes. That being said Will need to monitor trends to keep an eye on heavy rain potential going into the weekend - especially if the front does indeed make it into the area, providing a focus for more sustained convection. && .AVIATION... (18Z TAFS) Issued at 1244 PM CDT Mon Aug 18 2025 Outside of scattered showers and storms, conditions will remain VFR through the period. Have tried to target PROB30 and TEMPO groups to most likely locations and timing this afternoon. Convection should die down around sunset with light and variable winds overnight. && .MARINE... Issued at 1244 PM CDT Mon Aug 18 2025 No significant marine concerns through the period with generally benign conditions outside of convection. Isolated to scattered daily showers and storms will continue through midweek. Expect to see a fairly typical diurnal convective cycle with storms developing over the Gulf waters during the late night and and early morning hours, and transitioning farther inland by afternoon. Showers and thunderstorms will become more numerous late in the week as a weak frontal boundary stalls near or just north of the area. Winds will remain light at 10 knots or less with waves/seas 2 feet or less outside of thunderstorms. && .PRELIMINARY POINT TEMPS/POPS... MCB 73 94 73 95 / 30 30 0 30 BTR 74 96 74 96 / 30 40 10 30 ASD 72 94 73 95 / 20 30 10 30 MSY 79 96 79 95 / 20 30 10 30 GPT 75 93 75 93 / 20 20 10 30 PQL 73 94 73 94 / 20 20 10 30 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...Heat Advisory from 10 AM to 7 PM CDT Tuesday for LAZ034>037-039- 046>048-056>060-064-065-070-071-076>090. GM...None. MS...Heat Advisory from 10 AM to 7 PM CDT Tuesday for MSZ068>071-077- 083-086. GM...None. && $$ SHORT TERM...DM LONG TERM....DM AVIATION...DM MARINE...DM