UPDATE 9 AM, 8/22: Through the weekend, continued similar weather for Southwest Virginia, with highs mid 70s to low 80s, slowly warming a few degrees, and lows upper 50s to mid 60s, slowly warming a bit also, with scattered afternoon showers and storms possible. We’ll continue to watch the progress of Tropcial Storm Isaac westward into the Caribbean and the possible development of a Tropical Storm Joyce behind it. I’ll have a full update on a new blog post this evening. END UPDATE
UPDATE 5:15 PM: Tropical Storm Isaac has officially been declared by the National Hurricane Center, with a path bringing it into the Caribbean by Wednesday and possibly approaching the U.S. early next week. END UPDATE
This foggy, rather chilly morning in Southwest Virginia might have set record low temperatures if drier Canadian air had won the battle with the tropical moisture earlier this week. As it was, lows in the upper 40s to mid 50s still occurred in many locations along and west of the Blue Ridge, and even Roanoke dipped to 59. Another day of highs in the mid 70s to low 80s with scattered afternoon showers and storms is on tap. Expect a very slow warmup as the week progresses.
The tropical Atlantic is about to become a major meteorological and media obsession, and likely with good reason. Tropical Depresson Nine, approaching the Antilles, will likely become Tropical Storm Isaac (presuming the newest western Gulf of Mexico disturbance doesn’t beat it to development) later today or Wednesday, and then probably rapidly intensify into a hurricane. Forecast guidance varies on its track, but almost all of it has it approaching some portion of the Gulf Coast, Florida or Southeast U.S. coast by the early to middle part of next week (0Z GFS depiction for next Tuesday evening at left shows it moving into Georgia). If it can dodge the mountainous areas of Hispaniola and Cuba, it could well be a hurricane making U.S. landfall in about a week. Anyone with coastal plans should be monitoring the progress of this storm. There is of course some chance it will affect us in Southwest Virginia, but it’s too far out to determine that kind of detail yet. And then, there is another system behind this one that needs to be monitored as well.