Marine Weather and Tide Forecast for Zachary, LA

SHORT TERM
(Now through Tuesday)
Issued at 1043 PM CDT Sat Apr 18 2026

Cold front, as of 1115pm Sat, was along a line from Picayune to Kenner moving SE. The front will move well offshore today as high pressure builds. The front will become more elevated later this morning causing a stronger slope(rise/run) which will cause any moisture that moves up its sfc to become squeezed, considerably lowering the heights that can produce rainfall. This process is already causing lightning rates to fall dramatically. We will see this vertical squeezing as a decaying process for the shower activity through noon today. Cloud cover will do the same in that it will move SE through the daylight hours and should be near or along the coast by this evening. The front will bring in some dry air along with cooler temps dropping the area back into the low to mid 70s today for highs. A bit of warming Monday will bring highs into the mid to upper 70s then around 80 by Tuesday. Lows will be a bit cool during the morning Monday in the mid to upper 40s north to mid 50s south. Lows will also start to warm through the first half of this week. Otherwise, these conditions will be quite nice and normal for spring here as we watch the old battle of winter give in to summer.

LONG TERM
(Tuesday night through Saturday night)
Issued at 1043 PM CDT Sat Apr 18 2026

LONG TERM
Medium continues to show a pattern that is a little more progressive and not as stagnant. GEFS and ECS are both in decent agreement with a ridge over the southeastern CONUS heading into the 2nd half of the week but with a lot of coming in from the subtropical jet and a broad L/W trough over the western half of the CONUS. This should push the ridge to the east and suppresses it heading into the weekend. That said there are still some inconsistencies with respect to rainfall late in the forecast with the operational runs and the latest NBM is not as optimistic as the ensembles but it is 6/7 days away and the NBM is close enough so no deviations to the latest NBM at this time.

As mentioned heading into the second half of the work week a ridge will be dominating the southeastern CONUS. This will lead to highs back in the 80s for much of the area. Friday the first what will be more subtropical jet energy will work across the southern Plains and into the Lower MS Valley. Even though we won't get any cooler this will help to suppress the ridging aloft which may allow for some spotty showers Friday. The best chance of rain may be Friday night through Saturday as a weak cold front tries to slide into the area before stalling north of the Gulf coast. This will likely allow for better rain chances over through portions of the weekend and maybe some locally heavy rain across western/northwestern zones. /CAB/

AVIATION
(12Z TAFS)
Issued at 449 AM CDT Sun Apr 19 2026

A mix of IFR to MVFR will remain over the next few hours. Numerous showers with very few TS will rapidly dissipate as noon approaches today. Cigs will lift to all MVFR around sunrise this morning.
These cigs will then become VFR from north to south as the morning progresses, with all areas VFR by noon today.

MARINE
Issued at 1043 PM CDT Sat Apr 18 2026

A cold front will bring northerly winds around 25kt today thorugh Monday. Small Craft Advisories remain active for these conditions. Northeast winds will shift to east into Tuesday but remain elevated. Wednesday, winds will shift to a more SE direction and ease a bit to around 10-15 kt, possibly remaining that way for the remainder of the week.

LIX WATCHES/WARNINGS/ADVISORIES
LA...None.
GM...Small Craft Advisory until noon CDT Monday for GMZ529-531>536- 557.

Small Craft Advisory until 7 PM CDT Monday for GMZ541-543-551- 553-554-577.

Small Craft Advisory until 1 AM CDT Tuesday for GMZ570-572-575.

MS...None.
GM...Small Craft Advisory until noon CDT Monday for GMZ531>536-557.

Small Craft Advisory until 7 PM CDT Monday for GMZ543-551-553- 554-577.

Small Craft Advisory until 1 AM CDT Tuesday for GMZ572-575.