Water levels in ML change frequently. Often, differences can be dramatic over as little as a day, or two.
It seems widely accepted that wind plays a bigger factor than tide. There is a seasonal difference with winter being the lowest average water depth.
I find the attached link very helpful: http://waterdata.usgs.gov/fl/nwis/uv?02248380 Scroll down to the first chart: Gage height, feet. it is uncannily accurate once you have a baseline to judge it by.
Some would argue, but around .8 – 1.0 is about average. Once it starts going below .5, locals start saying the water is low. It can go down to negative numbers at times.
After the hurricanes of '04 it went up to nearly 3.0 and stayed high for months. Hope it helps.