Mermentau, LA Weather Forecast
Local 7-day forecast
Slight Chance Showers And Thunderstorms
Track current conditions, temperature changes, wind, and the full daily outlook for Mermentau, LA in one place.
A slight chance of showers and thunderstorms between 9am and 3pm, then a chance of showers and thunderstorms. Partly sunny, with a high near 87. Southeast wind 0 to 5 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
Local Weather Overview
This forecast page for Mermentau, LA is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: Jul 15, 2026 10:03 AM CDT.
The active forecast window currently covers Jul 15 to Jul 21, 2026 for Mermentau, LA.
Page Snapshot
- Page focus
- city weather
- Forecast window
- Jul 15 to Jul 21, 2026
- Latest sync
- Jul 15, 2026 10:03 AM CDT
- Forecast office
- LCH
- Source
- NOAA / NWS
Daily Outlook
This Week in Mermentau
Monday looks like the warmest upcoming period in Mermentau at 93 degrees F.
Tonight is the coolest period ahead with temperatures near 74 degrees F.
The strongest winds are forecast for Today at about 0 to 5 mph SE.
Precipitation is mentioned in 2 upcoming forecast periods.
Forecast Details
- Last updated
- Jul 15, 2026 10:03 AM CDT
- Coverage
- 7 days
- Time zone
- America/Chicago
- Forecast office
- LCH
- Radar station
- KLCH
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
A slight chance of rain showers before 7pm. Partly cloudy, with a low around 74. Southeast wind 0 to 5 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
Mostly sunny, with a high near 90. Heat index values as high as 102. Southeast wind 0 to 5 mph.
Mostly clear, with a low around 75. Heat index values as high as 100. South wind 0 to 5 mph.
Sunny, with a high near 92. South wind 0 to 5 mph.
Partly cloudy, with a low around 76. Southwest wind 0 to 5 mph.
Mostly sunny, with a high near 92. West wind 0 to 5 mph.
Mostly clear, with a low around 76. Southwest wind around 5 mph.
Sunny, with a high near 92. West wind 0 to 5 mph.
Mostly clear, with a low around 76.
Sunny, with a high near 93.
Mostly clear, with a low around 77.
Sunny, with a high near 93.
Mostly clear, with a low around 77.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Today
Jul 15
|
Slight Chance Showers And Thunderstorms
|
87°F |
0 to 5 mph
SE
|
|
Tonight
Jul 15
|
Slight Chance Rain Showers then Partly Cloudy
|
74°F |
0 to 5 mph
SE
|
|
Thursday
Jul 16
|
Mostly Sunny
|
90°F |
0 to 5 mph
SE
|
|
Thursday Night
Jul 16
|
Mostly Clear
|
75°F |
0 to 5 mph
S
|
|
Friday
Jul 17
|
Sunny
|
92°F |
0 to 5 mph
S
|
|
Friday Night
Jul 17
|
Partly Cloudy
|
76°F |
0 to 5 mph
SW
|
|
Saturday
Jul 18
|
Mostly Sunny
|
92°F |
0 to 5 mph
W
|
|
Saturday Night
Jul 18
|
Mostly Clear
|
76°F |
5 mph
SW
|
|
Sunday
Jul 19
|
Sunny
|
92°F |
0 to 5 mph
W
|
|
Sunday Night
Jul 19
|
Mostly Clear
|
76°F |
5 mph
SW
|
|
Monday
Jul 20
|
Sunny
|
93°F |
5 mph
W
|
|
Monday Night
Jul 20
|
Mostly Clear
|
77°F |
5 mph
SW
|
|
Tuesday
Jul 21
|
Sunny
|
93°F |
5 mph
W
|
|
Tuesday Night
Jul 21
|
Mostly Clear
|
77°F |
5 mph
SW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Mermentau.