textproduct: New Orleans/Baton Rouge

KEY MESSAGES

Updated at 147 AM CDT Thu Aug 13 2026

- Hot temperatures are expected for much of the forecast. Highs in the mid to upper 90s through the weekend with heat index values generally running in the mid 100s to near 110 through the end of the work week and then likely climbing into the lower 110's this weekend. Heat Advisories are in place for today, likely Friday and Heat Warnings likely Saturday, Sunday, and into the new week. Stay tuned. The impact of the afternoon highs will be exacerbated by the slightly higher than normal overnight lows; we just won't have a chance to cool off.

SHORT TERM

(Now through Sunday) Issued at 147 AM CDT Thu Aug 13 2026

Main forecast problem is how hot will we get and will there be any thunderstorms to mention. Both likely not the answers many of you are looking for. All thanks to a mid lvl ridge building on top of the region. Starting to sound like a broken record but what else can be said. As the ridge builds we will see strong subsidence due to increasing mid lvl hghts and mid lvl temps. Although the ridge will not be significant right now mid lvl hghts will rise some 4-5 dm hovering around 598dm by midday Saturday. We will also see some drier air, which is currently just south of the coast push into the area. At the sfc high pressure will control things at the level too with winds highly diurnal in nature. The combination of less moisture to work with, high pressure at the sfc, and increasing subsidence does not bode well for thunderstorm development. Now At this time still not confident enough to say there is zero chance of rain through the weekend but it is highly likely that most of the area will remain rain free. The best chance for isolated storms looks like late this morning through midday across coastal areas.

The other issue with the ridge building is the heat concerns. LL temps will slowly climb but luckily even with the building ridge LL temps never get on the extreme side. H925 may climb to 26/27C while h85 will be around 20-21C. This continues to suggest highs in the mid to upper 90s. The one hiccup that could lead to the highs climbing a touch more will be the dry ground. With the lack of rainfall for the last month plus the ground has really started to dry out and this could lead to a super-adiabatic skin layer which may help a few locations touch the century mark. However there will still be more than enough BL moisture to allow for the heat index to climb into the mid to upper 100s through Friday and then come this weekend some lower 110s. Heat advisory is already out for all of the area today and will likely be needed tomorrow and then we could need a few Extreme Heat Warnings this weekend. One other real nasty things about this heat, we have been and will continue to be unable to cool off overnight. Lows have only be able to dip down into the upper 70s to lower 80s for much of the region and with that we are not seeing any chance to recover and cool off.

Mentioned it yesterday and will put it on here again. With the lack of rain and well above normal temps we have been seeing we could quickly move into serious drought impacts along with the potential for fire weather concerns. /CAB/

LONG TERM

(Sunday night through Wednesday) Issued at 147 AM CDT Thu Aug 13 2026

The long term still continues to look hot with the upper ridge stretched from the Desert Southwest all the way to the western Atlantic. That said there is a very subtle weakness in the globals over the southern Mississippi River Valley. This will NOT shake the heat, but may help with a little less subsidence for a very slight uptick in convective coverage during the diurnal cycle. By this point, several days where highs in the 90s occurred with several likely nearly rain free days, the soil moisture will continue to decrease, which will help daily highs warm into the upper 90s to near 100 degrees later in the period. PWATs are still forecast to increase to around 2.0" which suggests better moisture quality with more limited mixing leading to higher surface relative humidity values. Bottom line here is with the higher temps and higher humidity, "feels like" temps will remain close to upper end of heat advisory or perhaps warning criteria.

Going through the end of the forecast period and perhaps slightly beyond, globals are struggling a bit with the overall synoptic pattern in terms of timing, however, both the ECM/GFS and respective ensembles show an upper level trough trying to dig either over the Central Plains or over the east coast midweek next week, which hopefully suppress and weaken the eastern extent of the H5 ridge. (Frye)

AVIATION

(06Z TAFS) Issued at 147 AM CDT Thu Aug 13 2026

VFR conditions currently in place at all terminals and this will likely continue for the foreseeable future. Rain chances are rather low but not zero however not confident enough to add PROB30 anywhere. /CAB/

MARINE

Issued at 147 AM CDT Thu Aug 13 2026

Generally benign marine conditions through the forecast period with high pressure mostly being in control from start to finish. Isolated nightly convection will be possible, especially over the offshore waters where locally higher winds and seas may reside around showers and storms with perhaps a waterspout or two. Overall, winds should remain mostly southerly at or less than 10 knots outside of convection. (Frye)

LIX WATCHES/WARNINGS/ADVISORIES

LA...Heat Advisory from 11 AM this morning to 8 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 11 AM this morning to 8 PM CDT this evening for MSZ068>071-077-083>088.

GM...None.