Marine Weather and Tide Forecast for Iowa, LA

DISCUSSION
(Today through Wednesday)
Issued at 1206 AM CDT Thu Jun 18 2026

The remnants of post-Tropical Storm Arthur are now onshore near Galveston and are not expected to re-enter the Gulf. While further strengthening is not a concern, we are looking at another round of heavy rain and gusty winds overnight and into Thursday morning.
Flash flooding remains a major concern, with an additional 2 to 6 inches of rain possible across Acadiana and southwest Louisiana tonight. Along with the heavy rain, there is also an isolated tornado threat as backing low-level flow will enhance 0-1 km shear, with models showing elongated low-level hodographs.

Local impacts will start to diminish on Thursday morning, with the coastal flood advisory being downgraded as surge levels reach roughly one to two feet above MHHW. In addition, we will be paring back the flood watch a little early, at least for parts of southeast Texas and central Louisiana. As Arthur continues to move further inland, subsidence will increase, leading to less cloud cover and an increase in temperatures, with highs in the 90s. With the remnants of Arthur still in east Texas, tropical moisture will cause dew points to be near 80. This combination will spike the apparent temperature well into the triple digits, and a heat advisory will be in effect for southeast Texas. For the rest of the week and heading into the weekend, we are looking at a more typical summertime pattern with temperatures in the mid-90s and high dew points. More heat advisories may be needed through the weekend. Over the weekend, ridging will start to build over the region, keeping rain chances below 20% for most of the area. The break from the rain will be much appreciated, as QPF amounts from Friday to next Wednesday are around 0.10 inches.

AVIATION
(06Z TAFS)
Issued at 1206 AM CDT Thu Jun 18 2026

Heavy rain and thunderstorms are impacting LFT and ARA. Near convection conditions will be IFR/LIFR with heavy rain and low ceilings. Elsewhere conditions will be MVFR with low clouds. Winds will be from the south-southeast around 10 to 15 knots.

MARINE
Issued at 1206 AM CDT Thu Jun 18 2026

The remnants of post-Tropical Storm Arthur are now located inland over Texas, and all Tropical Storm warnings have been cancelled.
Strong squalls will continue. Conditions offshore remain dangerous, as sustained winds are between 15 and 25 knots with wave heights up to 10 feet. Conditions will start to improve on Thursday, with winds dropping below 20 knots Thursday night. Wave heights will take a bit longer to subside, staying above 6 feet well into Friday. Over the weekend and into the start of next week, conditions will be calmer, with prevailing winds around 10 to 15 knots from the south and waves below 5 feet.

FIRE WEATHER
Issued at 1206 AM CDT Thu Jun 18 2026

Multiple rounds of heavy rain will limit any fire weather concerns for the next several days. MinRH values will remain above 50% for the rest of the forecast period.

LCH WATCHES/WARNINGS/ADVISORIES
LA...Flood Watch through this evening for LAZ027>033-044-045-055-073- 074-141>143-152>154-241>243-252>254.

Wind Advisory until 8 PM CDT this evening for LAZ027>033-044-045- 055-073-074-141>143-152>154-241>243-252>254.

Coastal Flood Advisory until noon CDT today for LAZ073-074-241- 252>254.

TX...Wind Advisory until 8 PM CDT this evening for TXZ180-201-259>262- 515-516-615-616.

Coastal Flood Advisory until noon CDT today for TXZ615-616.

Heat Advisory from 10 AM this morning to 9 PM CDT this evening for TXZ180-201-259>262-515-516-615-616.

GM...Small Craft Advisory until 7 AM CDT Friday for GMZ430-432-435- 436-450-452-455-470-472-475.