Already on the front-burner for America’s weather-interested, Tropical Storm Isaac — very likely soon to be Hurricane Isaac — is going to shout down all the politicians this week on your TV. In a way it already has, with the planned delay of any real action at the Republican National Convention in Tampa until Tuesday afternoon. The track of Isaac has been steadily nudged westward, so much that Tampa will probably only get a glancing blow on the low end of tropical storm status. But Isaac, having successfully dodged the mountains of Hispaniola and Cuba, now finds an open field of almost-hot ocean water, no land masses bigger than the Florida Keys and stable conditions aloft that will likely charge it up into a hurricane fairly quickly and possibly a major hurricane (Category 3 or stronger) or almost one before making landfall on the Gulf Coast late Tuesday or so. New Orleans to Apalachicola, Fla., seems to be the most likely spot for landfall, a slice of coast that has been blasted in the past few decades by the likes of Betsy (1965) and Camille (1969) and Frederic (1979) and Elena (1985) and Opal (1996) and Ivan (2004) and Katrina (2005), to name only a few. It’s very likely at this point that Isaac is going to be a big deal, potentially a very damaging hurricane with a large storm surge, and it may continue to be a big deal well inland, with flooding rains and a tornado threat extending far from the coast. Whether that shifts more toward the Tennessee and Ohio River valleys or more toward our region — or both — remains to be seen, as it depends on how an approaching low pressure trough/cold front and a high pressure system to the north interact with Isaac. Right now, you can pencil in a chance of rain for Southwest Virginia related to Isaac for Thursday and Friday. Even if the bulk of Isaac passes west, it may be positioned to pull in some southeasterly winds against the mountains to enhance shower chances — or its remnants could arrive a couple days later, pushed along by a cold front. As is typical with hurricanes and winter storms, you’ll see and hear lots of back and forth this week as various models and well-known forecasters offer different scenarios (I’m sure we’ll post a few on here in comments from time to time, as we have through the weekend). Keep up with the National Hurricane Center for the latest warnings and projected track.
As the week goes along, we’ll take a closer look at the potential effects for Southwest Virginia. Other than possible effects from Isaac, the week looks pretty normal, highs in the 80s, lows in the 60s, and some sporadic showers and storms. Often, this scattered activity tends to dry up a bit as a tropical system moves into the Gulf, as more moisture is consolidated near the tropical system and high pressure builds in response to the deepening low pressure with the tropical system. With a little more sun, a stray 90 or two may be possible for afternoon highs a day or 2 early to mid week — hasn’t happened at Roanoke since August 8.