Hurricane Isaac made landfall along the Southeast Louisiana Coast Wednesday morning as a category 1 hurricane with 80 MPH winds. As of 8 PM Wednesday, Isaac had weakened considerably with maximum sustained winds of 60 MPH. It is very slowly moving across Southern Louisiana headed toward the Northwest which will take Isaac into Northern Louisiana by Thursday afternoon. Isaac is then forecast to move into Arkansas by late Thursday evening. Below is the forecast track from the National Hurricane Center as of 10 PM Wednesday.
The storm will likely move over Western Arkansas, putting Central Arkansas in a position for very heavy rainfall. Typically in the case of Northward moving Gulf storms, heavy rainfall can extend well East of the center. Below is the radar image of Isaac from Wednesday morning. Note how the rain extends over 150 miles East of the center, but not much rain at all on the West side.
This is why the East side of a Gulf storm is usually referred to as "the wet side" of the storm. This means that even though the center of the remnants of Isaac will pass over Western Arkansas, the heaviest rains may occur over Central Arkansas. Again, this is highly dependent on the exact track of Isaac as to exactly who gets the heaviest rain. Below is the rainfall forecast from the Hydro-Meteorological Prediction Center for Isaac. It shows the heaviest rain just to the East of the forecast track through Louisiana right into Central Arkansas.
The forecast indicates the potential for up to 8 inches of rain in some spots. It is unlikely that widespread rainfall would be quite that heavy, but 3 to 5 inches of rain is quite possible over a rather large part of Central Arkansas. For this reason a Flash Flood Watch is in effect for Central Arkansas beginning Thursday afternoon into Friday.
Isaac will fall below Tropical Storm strength before moving into Arkansas, meaning maximum sustained winds will be less than 39 MPH. Wind gusts in and around the center may approach 40 MPH at times, leading to some potential downed tree limbs and power lines. A tornado risk also exists with Isaac. It is not unusual for tropical systems to spawn tornadoes, especially well East of the center. In 2008, the remnants of hurricane Ike produced 10 tornadoes across Arkansas.