Isaac remains a tropical storm per the NHC, despite a dropsonde observation of 70kt winds at the surface (hurricane force is 64kt), and 85kt flight-level winds in the NE eyewall. It is unclear why they have chosen not to upgrade Isaac, but he will be a hurricane at landfall, and strengthening. Isaac has continued to gradually deepen during the last 48 hour period at a fairly consistent pace, but dry air remains integrated with his circulation, making the eyewall ragged. This is what has prevented Isaac from becoming a major hurricane. The storm will be strengthening through landfall though, and Isaac will likely have upper-end Cat 1 winds coming to the surface at landfall due to turbulent mixing.
The biggest problem with Isaac will probably not be the wind but the extreme rainfall of 12-18 inches forecasted in the New Orleans and southern Mississippi area during the next 48 hours. This will cause flooding problems, along with a higher storm surge than one would typically expect from a Cat 1 hurricane due to its slow movement. Hopefully residents are not taking this storm lightly, as it will be a quite nasty one as it comes ashore in 12-24 hours, depending on exactly which point on the Mississippi Delta it crosses the coastline. Tropical storm force rain bands are already moving onshore. I will be posting short updates on Facebook throughout the day on Isaac.
We shall see what happens!