textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 138 PM CDT Mon Sep 14 2026

- Scattered pop up showers and storms on Monday afternoon, more isolated on Tuesday before becoming more prevalent on Wednesday.

- Drier air from a backdoor front brings more seasonably warm conditions and more comfortable humidity to the area on Thursday and Friday which will also drop rain chances. Rain chances return over the weekend, however.

- Stronger easterly winds may result in small craft advisory conditions for the latter half of the week in the coastal waters.

SHORT TERM

(Now through Thursday night) Issued at 138 PM CDT Mon Sep 14 2026

Summer's grip remains over much of the lower and mid-Mississippi River valley today with heat indices approaching 107 to 108 degrees in a few isolated locations (BXA, HDC, HZR, and NBG) so far. Reprieve in the form of pop-up showers and storms are beginning to bubble as convective temperature is reached over southern MS, Florida Parishes, and Bayou Parishes. The environment is plenty unstable (>4000 j/kg CAPE) with strong low-level lapse rates to promote these bubbling of updrafts though there is no additional lift beyond the low levels and mid-upper flow out of the east- southeasterly is 10 to 15 knots. This means there is little wind shear to assist in updraft development and showers and storms will be collapsing on themselves and unable to sustain themselves and further intensify today.

Much of the same is expected on Tuesday with the presence of surface high pressure remaining centered over the northern Gulf Coast. Heat indices will again reach the 100s though confidence is not high enough that these heat indices will reach the 108 degree threshold that would warrant a heat advisory at this time. Additional revisions to the forecast and increase in forecast confidence of the heat risk could warrant issuance in future updates.

By Wednesday morning, a backdoor front on the southwest flank of an expanding eastern CONUS high will provide lift for enhanced marine convection over the warm Gulf waters that will move inland over coastal areas throughout the day. This will also provide relief from the heat as cloud cover and breezy conditions (especially for coastal areas) will keep temperatures and heat indices cooler.

LONG TERM

(Friday through Sunday night) Issued at 138 PM CDT Mon Sep 14 2026

Thursday and Friday will provide our first glimpse of fall weather as an area of drier, Appalachian air will follow behind this backdoor front. This will provide notably more comfortable humidity values on Thursday and Friday with clearer skies and little to no afternoon rain chances. Highs will remain in the upper 80s to low 90s areawide, however. We'll take what we can get for September.

AVIATION

(18Z TAFS) Issued at 138 PM CDT Mon Sep 14 2026

VFR conditions at terminals though congested cu is building and pop up afternoon SH/TS will be isolated to scattered in nature through 00 UTC. PROB30s lines are in at terminals with highest chance of impacts with the most likely time windows. Some additional TEMPOs could be added for more significant terminal impacts though these will be short-lived. MSY and NEW have been left off PROB30s with lake shadow keeping environment slightly less favorable for TSRA impacts though there are updrafts building around the area and AMD lines could be warranted if trends suggest impacts are more likely. Light, variable winds will prevail aside from convective impacts. Fog impacts appear unlikely for Tuesday morning.

MARINE

Issued at 138 PM CDT Mon Sep 14 2026

A broad surface high centered over the area will keep benign conditions in place across the waters through Tuesday with light and variable winds of less than 5 knots and seas of less than 2 feet expected. A few showers or storms will pop up in the morning hours with some locally higher winds and waves possible as well as lightning and waterspouts especially on Wednesday morning. The pressure gradient will begin tightening Wednesday morning behind a backdoor front. This will cause easterly winds to increase to 15 to 25 knots with gusts upwards of 30 knots midday Wednesday through Thursday. Seas will respond to these higher winds and increase to 8 to 10 feet in the outer waters. These unsettled marine conditions will gradually abate late Friday and into Saturday. Some minor coastal flooding may also impact east facing shorelines over this period.

LIX WATCHES/WARNINGS/ADVISORIES

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