Bill’s effects will not just be felt along the impacted coastline as this will be a storm known more for the damage it causes from flooding rather than wind. Portions of eastern Texas and eastern Oklahoma, areas that certainly don’t need additional rainfall, could see anywhere from 3-6 inches with locally higher amounts over the next 2-3 days. This will escalate the threat of flash flooding across these areas. Rainfall amounts are a little less certain throughout the Midwest and Ohio Valley as the remnants of Bill will begin to track north and east. However, ample moisture should remain to produce respectable rain totals across these regions. Which will likely lead to areas of flooding in the Ohio river valley as well as portions of the North East; though not as widespread.
In terms of winds Bill is not that strong all things considered. That being said Verisk Climate’s Product Respond™ indicates the likelihood of winds gusting in excess of 65 mph along the Texas Coast, as well as sustained Tropical Storm strength winds in close proximity to major metropolitan areas such as Houston this is depicted in a sample of the Respond™ product below. Furthermore, today and in coming days isolated tornados cannot be ruled out in the area affected by Bill.
Tropical Storm Bill became the second named storm so far this year when the storm formed in the Gulf of Mexico South South-East of the Texas coast. Climatologically speaking this is a common area for development at this time of year, as depicted in figure 1 which portrays the average location of development for this week.
Bill started as an area of convection over warm water; current sea surface temperatures in the area are running at around 80° F which is the lower threshold for optimum development. Hurricane Hunters began flying into the storm to investigate throughout the day on 6/15/15. Sustained winds were above the threshold for Tropical Storm classification upon initial investigation but until 11PM on the 15th the storm lacked a well-defined center of rotation. Once this criterion was met Bill was named and the storm continued to become more organized and take on more tropical cyclone characteristics. As Bill progresses inland it is poised to drench areas that have already been inundated by rainfall.
Normally tropical storms quickly deteriorate once they propagate inland, however model consensus is hinting at a possibility of Bill feeding off energy due to a process known as Brown Ocean. In a nut shell; storms deteriorate due to the lack of energy input once they move away from the warm ocean water, in some rather rare cases (notably Ike ‘08, and Erin ‘07) this deterioration does not occur or is slow due to the brown ocean effect. Below is an example of how Tropical Storms feed off the ocean to strengthen, in the case of the Brown Ocean the storm is not being fueled by the ocean, but by moisture rich soil, which is abundant within Bill’s impact region due to recent flooding.
Looking ahead Bill will move North North-East through Texas into Oklahoma maintenance of strength is possible due to the effects of the Brown Ocean. Ultimately Bill will decay and is poised to move into the Ohio Valley where it could aid in the spawning of some severe weather. Then Bill will possibly interact with a northern stream system; should be better resolved as the model consensus comes into agreement. In any event the remnants of Bill will continue to bring the risk of flooding to the Ohio Valley and portions of the North East.