textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 527 AM CDT Thu May 28 2026

- Heavy rainfall continues to be the main weather threat through the remainder of the workweek. Some of the stronger storms will be capable of producing hourly rainfall rates of 1-3" per hour. With mostly saturated soils, high rainfall rates even over short periods could overwhelm drainage systems, leading to ponding of water in low lying and poor drainage areas. Localized flash flooding could also result in some roads becoming impassable, mainly in areas where the heaviest rain falls, or where multiple storms result in longer periods of moderate to heavy rain.

- A slightly drier pattern going into the upcoming weekend, however, isolated to scattered afternoon showers and storms will remain possible. With rain chances a bit lower, temperatures later this weekend will climb close to or exceed 90 degrees.

SHORT TERM

(Now through Sunday) Issued at 158 AM CDT Thu May 28 2026

A convective plume that develop just south of the CWFA last evening is moving north, however, weakening here with time. Satellite imagery over the last several hours has indicated warming cloud tops, so this feature will likely rain itself out over the next couple of hours just prior to sunrise.

Going into the morning and afternoon hours, the old convective plume will leave behind an old boundary, which CAMs are showing additional convective development along this feature as early as 6 or 7 am. Timing is questionable, but the overall potential for redevelopment is there. The main concern will be of course hydro with juicy PWATs increasing to 1.8-2.0" across much of the CWFA. Opted out of reissuing flood headlines for today due to some uncertainties in terms of spatial coverage and low confidence in terms of areas impacted. Most at risk will continue to be the MS Gulf Coast, but at this juncture it appears the heaviest precipitation will be west of the I59 corridor.

As we continue into the weekend the pattern finally begins to change a bit. First, on Friday, an H5 trough extending from the mid/upper low over the central plains moves over the region. Isolated to scattered showers and thunderstorms will remain possible, however, the best QPF signal within the models looks to be north of our area. By Friday night and Saturday the upper level flow quickly evolves to a more zonal flow and eventually some modest upper level ridging moving overhead, which will suppress rainfall chances just a bit. Despite the ridge there will still be a shot at diurnally driven convection along mesoscale boundaries during the afternoon or early evening hours. We will still need to monitor localized hydro concerns, especially for locations soaked over the last couple of weeks, but hydro concerns going deeper into the upcoming weekend look to be more the exception rather than the rule. As for temperatures, with heights rising and POPs on the downward swing, say hello to summer with 90 degrees looking more and more likely for several spots going into the weekend. (Frye)

LONG TERM

(Sunday night through Wednesday) Issued at 158 AM CDT Thu May 28 2026

It appears that we will still be in a rather blocky pattern at mid and upper levels Sunday evening, with ridging from east Texas to Minnesota. By mid-week next week, the ridge will progress eastward to the eastern Great Lakes on the north end, with the troughiness across the northern Gulf Coast pretty much gone.

Unfortunately, not really seeing much in the way of the airmass drying out. So, while there is no obvious synoptic scale lifting mechanism, moisture levels remaining high will mean we can't rule out isolated to scattered convection during the diurnally favored hours. In other words, afternoon and early evening thunderstorms. Considering we'll be turning the calendar page to June, that's not a terribly unusual occurrence. Areal coverage should be considerably less than what we've seen over the last week plus by the time we get into the workweek. So, instead of 60 to 80 percent PoPs like we've had most days recently, it'll probably be more along the lines of 30- 50 percent with no all day washouts by the time we get to Tuesday and Wednesday.

Little day to day change in temperatures is expected for early next week. At this point, the NBM numbers look like they could be a couple degrees too cool early next week, as forecast soundings and MOS guidance argue for highs closer to 90 degrees. Forecast lows look like they might have trouble getting below 70 until perhaps Wednesday morning across northern sections, and unlikely to fall below 70 south of the Interstate 10 corridor at all next week. (RW)

AVIATION

(12Z TAFS) Issued at 536 AM CDT Thu May 28 2026

Starting off with several sites at MVFR or lower this morning. This will likely improve a bit, but convection development is already occuring, which is expected to grow in coverage over the next couple of hours. Where showers and storms interact with local terminals, expect at least brief VIS/CIG reductions. Convection will remain possible through much of the day but decrease later this evening. More VIS/CIG reductions will be possible later tonight, especially MCB. Otherwise, light to moderate southerly winds continue. (Frye)

MARINE

Issued at 158 AM CDT Thu May 28 2026

A weak high pressure residing over the western Atlantic and eastern Gulf will maintain light onshore flow across the local coastal waters. Daily showers and storms will be capable of producing locally hazardous winds and seas, with a few cells each day capable of producing winds in excess of 34 kts. (Frye)

LIX WATCHES/WARNINGS/ADVISORIES

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