8pm Thoughts on Isaac

The latest Hurricane Hunter report says the developing eye has "broken apart" and that is confirmed by the latest satellite image (arrow).

The barometric pressure has risen by 1 millibar which, when combined with the break in the eye, tells me no significant strengthening will occur in the next few hours even though the storm is over by warm water and had good outflow at 30,000 ft. (usually conducive to strengthening).

Here is the 7pm CDT position (lower right) and the predicted path of the center of the storm. It is most likely it will move toward the mouth of the Mississippi River.

Here is the latest U.S. Global Forecast Model which I think shows a reasonable location and intensity in the form of a Cat. 2 hurricane (scale in knots of winds about 1,000 ft. above sea level). Unless it organizes aggressively so, that intensity forecast may be too high. I do have a concern that a prolonged north wind across Lake Ponchartrain with gusts to near 100 mph (as shown) could cause flooding of the lake into the city if the storm stalls.

click to enlarge

Here are the probabilities the storm surge will exceed 4 ft. above sea level:

Finally, here are the probabilities the storm surge will exceed 7 ft MSL:

Two posts down is a posting regarding flooding. Major flooding is certainly possible in the areas indicated.