textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 640 PM CDT Sat May 9 2026

- Complex 1: What's left of it will continue to slide south into the northern Gulf this afternoon, however a lingering boundary over south-central LA/Atchafalaya Basin will continue to support ongoing flooding concerns mainly along/south of I-10/12 thru this evening.

- Additional Development this Evening: Across SW LA could re- introduce more scattered to numerous storms later this afternoon/evening. Greatest confidence: West of I-55, then this activity (should) clear out tonight. - Complex 2: Monitoring upstream development over the ArkLaTex region early Sunday morning and how this will evolve as it moves southeast towards our area later on Sunday into Sunday Night/Monday Morning. Confidence is greater on this idea, but models are still struggling at initial depth/strength of development. Something to continue to monitor.

- Impacts: Main risks will continue to be areas of flash flooding, large hail, locally damaging wind gusts, isolated tornadoes will the the overall lowest risk. This is a low-cofidence forecast regime, people with outdoor plans should remain weather-aware.

- By Monday, the final activity slides through and we begin to clear out Tuesday thru late-week, entering another dry period with temps warming back to the upper 80's.

SHORT TERM/MESOSCALE

(Now through Monday Night) Issued at 1233 PM CDT Sat May 9 2026

Well, this is complicated, so bare with me. Starting out with this afternoon, yet another in a series of many disorganized MCS clusters have rolled through the area, providing widespread heavy rain through the morning. Took an easy approach at 1) lowering highs today which also lowered the diurnal curvature throughout the day and 2) blended in with the PPI01 NBM with a heavy lean on the HRRR. Will strongly note after the past previous days, the HRRR has been a rather good performer at these complicated series of complexes. It's very difficult to narrow down exact timing and details, with confidence quickly dropping off after each complex passes (because how the next evolves has everything to do with the previous one, etc etc). So, not expecting the CAMS to nail any of these perfectly, at all, instead, want to look at a broad approach at the idea, utilizing RRFS/REFS trends aligned with HRRR being the main best performer. When both models align, confidence turns high, when they dont, we take a step back and investigate further. This complex this morning 12-24 hours out was well handled, and the 12Z today introduces a few items to look at. Seeing clustering in REFS/RRFS/HRRR guidance at the idea of continued afternoon/evening convection, which quite frankly makes sense given the hangup of the remnant outflow boundary from the morning complex pushing south into the Gulf, and hanging up more NW to SE over the southern Atchafalaya Basin. This introduces a continued focus for lift based on sfc confluence and a notable instability gradient that likely will not move much today. In addition, progressive westerly flow along a broad region of weakness will surge PVA slugs our way through the day, adding to the many subtle lift mechanisms at play (that all add up). With all of that, said, concerned for the ongoing and continued re- development of heavy rain showers throughout the rest of today, and will caution specifics will be difficult, as for now it might be a merge of heavy rain concerns along/south of I-10/12 and additional development impacting northern areas later on. Check back, monitor radar updates to help with plans, if needed.

Beyond this activity, if this messy amount of re-development persists, it will try to surge east along the mean flow with time mainly later this evening into tonight. The intensity of eastward progression will be all dependent on how much time we have to recover following this complex, which so far doesn't look like much and might just add more stratiform/heavy rain through the evening before clearing out tonight.

Going into Sunday, Yep, hate to say it but we'll need to monitor yet another complex over OK, NE TX, AR and northern LA. REFS/RRFS/HRRR guidance splits into confidence, per usual, as initial strength/location of the development of upstream convection will translate into the impacts we see (or don't see) for our area. But, for now it's being mentioned/messaged something to closely watch - primarily late Sunday into early Monday. The dynamic lift associated with this is confident, don't get me wrong. Obvious subtle shortwave axis and attendant PVA will support storms to ignite somewhere in the upstream area mentioned before, but again, downstream progression will need to be monitored. Will make one forecaster note specific to the 12Z HRRR, I'm not buying, at all, a complex midday Sunday over northern LA suddenly decaying during peak heating, as instability and cold pool lift will likely keep any complex rolling through. But, should that happen and we are largely untouched all morning/afternoon, we'll see enough instability to fuel pop-up storms. Banking heavily on the idea of some sort of complex making it through Sunday night/Monday morning. Overall, damaging winds, large hail, isolated tornadoes and a persistent concern for flash flooding will continue with each complex.

LONG TERM

(Tuesday through Friday Night) Issued at 1233 PM CDT Sat May 9 2026

Believe it or not, it's all over going into later on Monday into Tuesday, as this shortwave impulse continues southeast and ridging takes over allowing for an upstream high to take over through the rest of the week. No adjustments necessary in the extended, with high confidence we'll warm right back up to the upper 80's by mid/late week with little to no rain chances to speak of. KLG

AVIATION

(00Z TAFS) Issued at 640 PM CDT Sat May 9 2026

The rain has begun to dissipate in the next few hours and will continue to do so through the remainder of the evening. TEMPO groups indicating some MVFR visibilities and ceilings are in place at the terminals through around 04z to reflect the periods of passing light rain showers. After 08z, the combination of light winds, high humidity, and saturated soils will allow for fog to form at MCB, BTR, and HDC. Prevailing IFR conditions due to the fog will be in place at these terminals through 15z. After 15z, increased mixing from daytime heating will allow the fog to clear. ASD and GPT will also be impacted by low stratus between 10z and 14z resulting in prevailing IFR conditions. These terminals will also see improvement after 15z. At MSY, NEW, and HUM prevailing MVFR ceilings are expected through the period. Additional convective activity is expected to develop after 18z tomorrow with periods of reduced visibilities and ceilings as a stationary front continues to linger over the region.

MARINE

Issued at 1233 PM CDT Sat May 9 2026

South to southeast winds of 10 to 15 knots will persist through the weekend. Main impacts will be multiple clusters/periods of showers and storms at times through Monday morning providing strong to severe storms across marine waters. Main threats will be wind gust greater than 34 knots and waterspouts. A frontal boundary will move into the waters Sunday night into Monday, bringing offshore winds and drying out conditions through the end of the upcoming week. KLG

LIX WATCHES/WARNINGS/ADVISORIES

LA...None. GM...None. MS...None. GM...None.