Being right at the northern border of the Gulf of Mexico with prevailing winds from that water, there is almost always an abundant source of humid air. Likewise, almost any Low system will bring in cooler air from its northwestern side. Thus the chances for rain are almost constant at those times. I live a few hundred miles north of Louisiana, but we expect rain during this season, it is usually a longer lasting, slow rain than the thunderstorm variety. I suspect it is similar in Louisiana, but with their proximity to more moisture and warmer temps, they probably have more convective weather. I suppose this time of year would be considered the "rainy season" for much of the Southeast and even the Southwest US.
Off topic: Not sure what your plans are but I would certainly suggest some touring of the nearby areas of antebellum homes and plantations, mostly west of New Orleans. There are also many historic (in US terms, anyway) buildings in the French Quarter area of the city. It will probably be too late to catch a glimpse of alligators, but a tour of some of the swamps should still be considered, perhaps in a covered boat!
Of course, you should also be prepared to gain a few pounds from sampling the great variety of cuisines! Louisiana has been controlled by many different nations, well before they became a State. There is also an outstanding aquarium and an equally outstanding National WWII Museum.
Enjoy your visit! [removed link to the now castly photobucket.com site]
This will give you a good idea of what sometimes happens in the Fall, it's much more 'normal' in Spring and Summer, however. Hopefully, this line will slowly dissipate as evening continues. But if it doesn't get moving, it will simply build up tomorrow...
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