textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 558 AM CDT Sat Jul 18 2026

- A mostly dry pattern is expected into next week. The primary concern will be increasing heat. Heat indices will be in advisory criteria today through Monday and could approach heat warning criteria by the middle of next week.

- Isolated to widely scattered thunderstorms will begin to develop mainly along and east of I55 during the late afternoon hours today through the first half of the new week. Eventhough chances of storms will remain low, those that do develop could be strong to severe.

SHORT TERM

(Now through Tuesday) Issued at 1113 PM CDT Fri Jul 17 2026

Heat will be our main issue for the next several days. A heat advisory will be issued with this package for today. We will let this one end befor issuing for Sunday and again Monday. We should see ambient temps reach the mid to upper 90s today through Monday and it would not surprise me if we see a century mark at some point over the next several days. This is all brought about by strong suppression and a westerly to northerly flow for the next several days.

The next thing to discuss is the system currently in the SE gulf. What is being looked at is the circulation center located rougly 250 miles SSW of Tampa Bay FL at midnight this Saturday morning. The low level flow is obviously cyclonic but so is the upper flow, and when the upper level winds are looked at, it shows a TUTT low interacting with this sfc feature. Over the coming days, models differ, not only with each other but even with run to run within their own physics packs with where this TUTT low will be over the coming days. One thing has remained the same though, and that is it will continue to plague the low level sfc circulation causing moderate shear over it at first, then weakened shear by the start of the week allowing a broad sfc low to develop(via run to run consistency). Today, this feature races up the west coast of FL landing in the NE gulf by midnight tonight. This is where it slows to a crawl while maintaining some northerly direction as a weak sfc low as it waits on a front and short wave to bring whatever remains to the northeast. The short wave that drops into the central CONUS and eventually into the SE CONUS is currently located near 31N 137W over the Pacific this morning. There is very little cloud cover associated with this at the moment, so only crude satellite profile data can be used. But we should see this get sampled by the upper air network at the earliest Sunday 7pm(00Z Monday) along the NW coast. This would be the earliest look at the timing and where the short wave will be to retrieve the NE gulf mess. The deep moisture will slowly edge into our area through mid week bringing a small increase(~30%) of rain. The storms that form late in the day as convective temps will be quite high. And since there is a lot of heat energy and only several storms around, each will not have to compete for the heat and will be capable of being strong/severe.

LONG TERM

(Tuesday night through Friday) Issued at 1113 PM CDT Fri Jul 17 2026

Strong upper level ridge will continue to hold over much of the CONUS along with surface high pressure centered over TX/LA. This along with increased moisture will bring high temperatures into the mid and upper 90s with a possible run at 10. Heat index values will start in the mid to upper 100s but by mid week we could see values in excess of 110. So heat advisories will be likely needed early this week followed by potential for extreme heat warnings mid week.

Uncertainty remains on the disturbance located south of the Florida peninsula outlooked by NHC. The eventual outcome of this will depend on how strong the ridge is versus the trough that starts to dig down mid next week. Ensemble guidance does show some kind of low pressure developing mostly to the east near Florida but there are some members hinting it could be a little closer to Louisiana and Mississippi. Depending on how close this is, moisture pulled in from here may help increase the summertime diurnally driven storms which could give localized relief for the heat.

AVIATION

(12Z TAFS) Issued at 558 AM CDT Sat Jul 18 2026

VFR through this taf cycle.

MARINE

Issued at 1113 PM CDT Fri Jul 17 2026

Surface high pressure centered near and just southeast of the Mississippi River mouth will maintain a generally west to northwest wind at around 10 knots through the weekend. The northwest to north flow will be strongest during the overnight hours approaching 15 knots before winds diminish during the day. Thunderstorm coverage will remain very limited today but isolated storms may reach the eastern waters tonight through Monday as the eastern-Gulf upper low edges closer, but most of the marine area should remain dry. By mid week, winds remain westerly at around 10 knots and rain chances will also increase modestly in waters east of the Miss River as deeper moisture returns, although widespread marine convection is not presently expected.

LIX WATCHES/WARNINGS/ADVISORIES

LA...Heat Advisory from 10 AM this morning to 6 PM CDT this evening for LAZ034>037-039-046>048-056>058-064-070-071-076>087- 089>100.

GM...None. MS...Heat Advisory from 10 AM this morning to 6 PM CDT this evening for MSZ068>071-077-083>088.

GM...None.