Most of the Midwest received from two to more than seven inches of rain from Isaac. However, the amount of rain depended greatly on whether or not your gauge happened to be underneath one of the heavier bands of showers and thunderstorms rotating around the center of Issac.
As you might expect, Isaac gave the drought a good kick in the teeth from Missouri eastward. If you compare the U.S. Drought Monitor of August 28 to that of September 4 the areas of improvement are clearly apparent. One thing to note, however, is that "islands" of Severe and Exceptional Drought (darker reds) persist within the larger areas of improvement. These "islands" are a reflection of the banding of showers and thunderstorms in Isaac's circulation in which some areas received much less rain than areas not far away..
|This is an animation created from maps of 24 hour precipitation amounts from|
August 31 through September 3, 2012. The maps in this animation
are from the NWS Advanced Hydrologic Prediction Service.
Note that while Issac improved the drought situation by one to two categories in some areas, Severe to Exceptional drought is still firmly entrenched over much of the central U.S.