textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 1051 PM CDT Sat Jun 20 2026

- Dry conditions are expected to start the week. Lower numbers of showers and storms are expected starting today with only isolated activity Monday and Tuesday allowing the area to dry out.

- Extreme heat is expected for Monday and Tuesday. Heat index values should approach 108 degrees and heat advisories may be necessary.

- Scattered storms will begin to move back into the area by mid week. These storms will be capable of producing isolated areas of severe weather.

SHORT TERM

(Now through Tuesday night) Issued at 1051 PM CDT Sat Jun 20 2026

After looking at everything we can get our eyes on to find any change in this wet pattern, we have found it. Looking at the big pic, synoptically speaking, one can easily see in WV imagery the deep tropical moisture feed coming from southern Mexico and the EASTPAC areas that has been plaguing the area with tropical rainfall for a while now. Now take a look stage right at an incoming TUTT low in that WV imagery. This does not look exciting at first, but what this will do later today and this week will be very helpful. The dry air on the northern and western flanks of this TUTT low will move into this tropical plume basically cutting it in an east west fashion. The way to see this is with any global model with RH imagery using an atmospheric layer from 850mb up to 700mb. Then using H3 wind barbs, one can easily see the TUTT lows position at the Yucatan Pen and eventual path it will take as well as how the dry air impacts this deep moisture plume. This is what causes our sh/ts coverage to be cut to almost zero by Monday and Tuesday. But then a large upper trough begins to set up over the eastern half of the CONUS. The orientation of this trough will be NW to SE for our area bringing us a NW flow regime. This flow will bring MCS type features from the Red River region into the area starting late Tue or overnight Tue night. But the thing that is different this time is there is no deep tropical moisture to work with. PW values begin to drop today from a soupy 2.25" to 1.3" by Tuesday. This means these storms will be more capable of producing severe wx instead of flooding rainfall. The faster movement will also add to lower rainfall amounts for any particular area than what we have been seeing the last several weeks. This does not mean there will be an outbreak of severe wx, just the odds are better than flooding rainfall, although this is not factoring antecedent conditions. This signal of tropical moisture being cut off is quite normal for this time of year. Basically, climatology shows us that the May-June time frame brings this deep moisture feed northward into some location along the gulf coast from Florida to TX. It's even been as far west as Laredo up to San Antonio. This normally makes headlines with extremely impressive rainfall tallies wherever it lands like it has for our area this year. Wherever it lands can bring those locations almost a normal year worth of rainfall within just a few weeks. Way back in my younger years as a met, I would hear the more seasoned mets discuss this conveyor as the "Gulf Monsoon" or the "GULFPAC Monsoon". When studied, it shows that some years are wetter than others. Some of my co-workers and I were discussing how this feature caused severe flooding in the Pensacola/Mobile area a few years back and has caused city wide flooding of Houston and San Antonio in previous years. But it always went out as quickly as it came in, and by July, this feature is normally gone. The signal that is coming in now with the TUTT low(and development of the SW stacked high/downstream east coast trough) could be just the thing that tames this feature but we will see how this trasformation progresses.

LONG TERM

(Wednesday night through Saturday) Issued at 1051 PM CDT Sat Jun 20 2026

With upper level high pressure sitting over the desert southwest and northern Mexico, a northern stream trough will begin to deepen over the eastern half of CONUS on Wednesday. As this troughing develops, the flow aloft will turn more northwesterly. There are indications that a large MCS could form over the southern Plains Tuesday night into Wednesday morning and then sweep southeastward, following the theta-e moisture axis, into the forecast area by the afternoon hours. The system will be weakening as it moves into the area, but gusty winds and some locally heavy downpours will be possible across the northern half of the CWA during this time period. The increase in cloud cover and rain chances will also help to temper the extreme heat with highs falling closer to average in the upper 80s and lower 90s and heat index readings dropping back to between 100 and 105 degrees.

Thursday will see the upper level trough begin to pull to the east and the influence of the upper level ridging begin to increase. Overall, the day should be a fairly typical Summer day with highs climbing into the low 90s and scattered diurnally induced convection firing up in the late morning and afternoon hours. Rain chances will be highest north of I-10 where the influence of the ridge will be lowest and near average PoP for late June of 30 to 50 percent is forecast. South of I-10, only isolated activity is expected due to the slightly stronger capping inversion aloft.

Friday will continue to see the influence of the ridge grow as the trough pulls out of the area. A return to a warmer and drier pattern is expected as temperatures climb back into the low to mid 90s and rain chances fall to around 20 percent for the afternoon hours. These lower rain chances are direct result of the drier air dropping PWATS below average or around 1.5 inches and the increasing mid- level capping inversion that reduces mid-level lapse rates to below 6.0 C/km and drops MLCAPE to around 500 J/KG. The one thing to keep an eye on is the threat of strong wind gusts from any storms that do form as dry air entrainment into the updraft could occur.

By Saturday a zonal flow has developed with an upper level band of high pressure extending from Pacific to Atlantic. This brings classic summertime weather with afternoon thunderstorms predominating the pattern. [PG/Schlotz]

AVIATION

(06Z TAFS) Issued at 1051 PM CDT Sat Jun 20 2026

VFR seem to be the rule this morning. Some cigs at the coast are in and out of MVFR. MVFR to IFR cigs should build back into the northern half of the area before sunrise this morning, but these cigs and all terminals will go VFR before noon. This may sound like a broken record, but TSRA will be around at several terminals again today. But not as many around like there has been. It is possible that a terminal actually go through the day without sh/ts. Tonight will be much of the same with lower cigs north causing IFR to MVFR conditions and VFR toward the coast.

MARINE

Issued at 1051 PM CDT Sat Jun 20 2026

A broad area of high pressure will build back over the eastern Gulf waters for much of this week. This along with a large east coast trough developing will provide persistent onshore winds of 10 to 15 knots and seas of 2 to 4 feet through this week.

LIX WATCHES/WARNINGS/ADVISORIES

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