Area Forecast Discussion

KEY MESSAGES

Updated at 617 PM CDT Thu Jun 11 2026

- High temperatures are expected to climb into the mid 90s Friday through Sunday with heat index values approaching 105 degrees during those days. This is our first heat spell of the summer, so please use cautions if outdoors or an extended period of time.

- A weak cold front will slowly move into the area during the first half of next week leading to higher shower and thunderstorm chances. This has correlated to a higher Flash Flood risk starting on Monday with a Slight Risk (Level 2 out of 5) for Flash Flooding.

SHORT TERM

(Now through Sunday night) Issued at 104 PM CDT Thu Jun 11 2026

A 500mb ridge looks to stay parked over the northern Gulf coast for much of the end of the week and weekend. Dry air above 850mb coupled with the suppression of the ridge has kept showers at bay today. Therefore, this is allowing temperatures to soar into the low to mid 90s with heat indices approaching 100. The ridge over the northern Gulf is also promoting quite an expansive Bermuda high centered over the Atlantic. This will primarily drive low- level moisture into the area, with today being the "driest" day. With the added moisture from the south-southeasterly surface flow, light patchy fog is expected to develop mainly across southwest MS and the adjacent Florida Parishes. However, any fog that develops should quickly mix out right at sunrise.

Friday will largely be a carbon copy of Thursday, but with the added moisture from the south-southeasterly surface flow, we will have a little more moisture throughout the atmosphere. According to the HREF and REFS, overall PW values will start approaching the 90th percentile across coastal SE LA as a surge of moisture around 850mb occurs across that area. This will help promote higher dewpoints and muggier conditions with heat indices approaching 105 along with an increase in showers and thunderstorms during the early afternoon and evening. This will be one of our first days approaching heat advisory criteria, so it's important to be careful while outdoors. Areas along and north of I-10 will still have drier air at 850mb, keeping the PW near average with lower PoPs at 5-10%. Any convection that does form in the southern half of the area should dissipate shortly after sunset as we lose the daytime heating.

We continue to get pumped with low-level moisture as the aforementioned ridging and Bermuda high hold on for one more day with southeasterly surface flow. By this point, low-level moisture should be in place over the whole area, but high-resolution models seem to agree that most of the convective activity should once again be limited to southern SE LA along seabreeze boundaries. So, PoPs were raised slightly down there to account for those expected showers and thunderstorms. It'll once again be muggy with heat indices approaching 105 as the mow-level moisture stays in place. Once again, any storm that forms Saturday afternoon and evening should dissipate rather quickly once the sun goes down and we lose daylight heating.

Sunday looks to be the day we finally break down the stubborn ridge over the northern Gulf Coast. Medium range guidance agrees that a shortwave coming down across the central high plains will break down the ridge and retrograde it westward into northern Mexico. This will do a couple of things for us: it'll throw a weak cold front south across the Ozarks and lower MS Valley and promote even higher moisture on Sunday. So, the moisture and the forcing of the front will promote scattered to numerous showers and thunderstorms across much of the area. On the bright side, it will be a little cooler (low 90s...) than the previous days.

LONG TERM

(Monday through Wednesday night) Issued at 104 PM CDT Thu Jun 11 2026

Medium range guidance agrees that the shortwave will slide to the east across the mid-Atlantic Monday which will promote zonal flow across the area. This zonal flow means that the previously mentioned front will lose its forward momentum and stall out across northern Louisiana. This means that the moisture pooled out ahead of the front will be primed for repeated rounds of showers and thunderstorms Monday through at least Wednesday. Because of the stalling front, we will see an increased risk of heavy rainfall and flash flooding across the area the first half of next week. In fact, we are already outlooked in a Slight Risk (level 2 out of 5) for excessive rainfall on Monday. The silver lining is that it will "cool off" into the low to mid 80s during that timeframe. Portions of the area have already seen over a foot of rain in the past 30 days, so those areas are especially vulnerable to any flash flood risk early next week. Details on exactly where the highest amounts are and how much it'll be are still shaky at this range. So, it's best to keep monitoring the forecast for any changes as we head into next week.

AVIATION

(00Z TAFS) Issued at 617 PM CDT Thu Jun 11 2026

All forecast terminals VFR at forecast issuance time and expected to remain that way for at least the next 6 hours. There are a few SHRA on radar, including one over Lake Pontchartrain. No indications of lightning over the last hour or so, but the threat would be non-zero at KHDC and the New Orleans terminals through about 02z. Not enough of a threat to mention in the forecast though. MVFR conditions possible toward sunrise at KMCB and possibly at KASD, but those will improve quickly after sunrise. Isolated TSRA possible during the afternoon on Friday, and will carry PROB30 at several terminals until around 23z.

MARINE

Issued at 104 PM CDT Thu Jun 11 2026

A broad area of high pressure will remain centered over the eastern Gulf and Florida through the weekend and into early next week, promoting a persistent south-southeast wind of 10 to 15 knots across the coastal waters through early next week. These winds will produce seas of 2 to 4 feet in the open Gulf waters and 1 to 2 feet in the sounds and tidal lakes. Afterwards into next week, a stalling front will increase rain chances and winds through at least the middle of the week.

LIX WATCHES / WARNINGS / ADVISORIES

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