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171 FXUS64 KLIX 160423AFDLIXArea Forecast DiscussionNational Weather Service New Orleans LA1123 PM CDT Fri Aug 15 2025...New SHORT TERM, LONG TERM, AVIATION, MARINE....SHORT TERM...(Today through Monday Night) Issued at 1059 PM CDT Fri Aug 15 2025A weak upper level vorticity max and an associated pool of deepermoisture will move through the Gulf South today, and this willlead to higher PWATS of between 2 and 2.1 inches across theforecast area. This deeper pool of moisture and the weak forcingaloft associated with the vorticity max will support another dayof greater convective development across the area. Convectionshould develop by the late morning hours along the seabreezeboundary in coastal Louisiana and then spread northward beforereaching southwest Mississippi by the late afternoon and eveninghours. Given the more favorable conditions for shower andthunderstorm activity today, the PoP forecast has been increasedslightly to a range of 50 to 70 percent. Storm motion will remainat 5 knots or less, so there could be some localized streetflooding issues with the heaviest storms today. Due to the higherrain chances, the temperature forecast has been lowered a few degrees and this will keep heat index values near or just slightly below advisory levels this afternoon. However, the heat advisory is already active for tomorrow, and there could be windowwhere advisory criteria is briefly hit in the mid to late morninghours before the thunderstorm activity gets going. Sunday through Monday night will see a return to more averagePWATS in the 1.6 to 1.9 range as the vort lobe pulls to the westand some drying aloft takes hold. Temperatures will also be nearaverage in the lower 90s each day and heat index values willremain below advisory limits at around 105 degrees. Overall, avery typical mid-August regime will be in play. Diurnally inducedscattered showers and thunderstorms will develop along the seabreeze or pre-existing outflow boundaries each day beforequickly dissipating in the early evening hours with the loss ofdaytime heating. PoP values will be near average in the 30 to 50percent range. &&.LONG TERM...(Tuesday through Saturday)Issued at 1059 PM CDT Fri Aug 15 2025Tuesday will see little change from the pattern observed on Sundayand Monday with normal August conditions expected. However,another surge of moisture will feed into the area on Wednesday asa broad ridge over the region shifts to the west and a weak troughaxis and associated surface boundary drift toward the region.PWATS will quickly increase to between 2 and 2.2 inches once againon Wednesday and remain at those levels through Saturday. Thepattern is also more supportive of a series of mesoscaleconvective complexes forming over the Arklatex region and thensweeping southward as a split flow pattern forms over the LowerMississippi Valley. This is something we will need to monitor asthese convective complexes can produce stronger winds and veryheavy rainfall. These complexes may also lead to later convectiveimpacts as the storms initially form to the northwest of theregion and then sweep in through the evening hours. This concernis reflected by having lingering chance PoP in the forecast through the late evening hours. In fact, there may be the typicalinitial convective activity that forms along the seabreeze front in the late morning and early afternoon hours and then a secondaryround of thunderstorms that moves through in association with anymesoscale convective systems that do form. Temperatures should benear or slightly cooler than average from Wednesday onward due tothe increased convective activity expected. More refined details on the evolution of this pattern will develop over the coming days and forecast confidence in this overall pattern will also increase. &&.AVIATION...(06Z TAFS)Issued at 1059 PM CDT Fri Aug 15 2025The primary concern for aviators will be scattered to numerous showers and thunderstorms that could impact the terminals for timeto time mainly between 17z and 00z. Brief periods of gusty winds to around 20 knots, lightning strikes, and downpours that could reduce visibilities to MVFR range or lower can be expected with any storms that pass over a terminal. PROB30 and TEMPO wording is in place to reflect the convective risk at all of the terminals between that 17z and 00z time period. Outside of the convective threat, VFR conditions will be the rule at all of the terminals through the entire forecast period. PG&&.MARINE...Issued at 1059 PM CDT Fri Aug 15 2025The Summer doldrums will continue across the coastal watersthrough the middle of next week. Light winds of 10 knots or lessand seas of 2 feet or less can be expected. Shower andthunderstorm activity will also develop in the early morning hourseach day across the offshore waters. The storms will then movemore inland and impact the tidal lakes in the afternoon hours. Anyof these storms could produce locally higher winds and waves. Afew could also produce some waterspouts.&&.PRELIMINARY POINT TEMPS/POPS...MCB 93 73 92 74 / 50 10 50 20 BTR 90 75 93 77 / 60 10 60 30 ASD 92 75 92 76 / 40 10 60 20 MSY 89 79 91 80 / 50 10 60 30 GPT 93 77 90 77 / 40 10 60 20 PQL 91 76 90 76 / 30 10 60 20 &&.LIX WATCHES/WARNINGS/ADVISORIES...LA...Heat Advisory from 10 AM to 7 PM CDT Saturday 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 Saturday for MSZ068>071-077- 083>088.GM...None.&&$$SHORT TERM...PGLONG TERM....PGAVIATION...PGMARINE...PG
