Thunderstorms rumbled across Galveston County early this morning, bringing more rain to the already water-logged area. So far this month, Scholes Field in Galveston has picked up 13.78 inches of rain already, while the National Weather Service Office in League City had recorded 12.80 inches for September through yesterday evening. Even those amounts are modest to some areas of the Island and the County which have received several inches more than those at the official reporting sites.
Although more rain is likely as a low to our south and a stagnant frontal boundary along the coast provides ideal conditions for precipitation, amounts over the next day or two are not likely to be quite as high as seen lately. Still, any rain will pose some threat of flooding due to already soggy conditions.
While national attention will naturally be focused on the threats from Major Hurricane Florence, locally there seems to be more interest on how a tropical low (Invest 95) will impact Texas over the next few days and what threat, if any, Tropical Storm Isaac provides in the long run. After becoming somewhat disorganized overnight, this system has now formed a surface low and is showing some potential for development. As a result, the Hurricane Center has upped the chances for development to 70% over the next few days and aircraft may investigate the area tomorrow.
Fortunately, most models suggest that if the system does develop it will most likely be as a tropical depression or relatively minor tropical storm as it makes landfall somewhere between northern Mexico and the middle Texas coast on Friday or Saturday.
If this scenario holds, then rainfall totals may not be quite as high locally as they could be with a more northerly track and/or a stronger storm. Still, we can expect some rain and gusty winds as we end the week, along with elevated tides, which are already running a foot or so above normal levels.
Finally, looking ahead, Tropical Storm Isaac is expected to move into the Caribbean. Most models do not intensify this storm due to wind shear in the region and either keep it heading west towards Central America, or turning north well east of Texas. An upper-level high pressure ridge expected to build in by Sunday and Monday, may keep it well to our south. In addition, it may bring a return of sunny, mostly dry weather for next week!