The upgrade to Humberto may seem a bit rapid, but all should keep in mind that Humberto was really likely a Storm before they issued the first advisory. (Per the 11AM TD 9 Discussion). It would appear that Humberto had become a depression sometime near or just either side of daybreak, in all actuality.

While there is likely a real chance Humberto does strengthen into a significant wind event, as well as rain event, for Texas and/or Louisiana, given its slow movement and proximity to already very soaked land, the single greatest impact from Humberto is likely to be more flooding. Widespread flooding, and a significant possibility of locally catastrophic flooding, is the theme here. This is our lot out here in Texas 2007.