UPDATE 9:30 PM: The Roanoke and New River valleys have stayed mostly dry today — but Galax has been inundated, with reports of a foot of water flowing through many city streets and overflowing creeks. The juice is still there to squeeze out heavy showers and storms randomly over the next couple of days, with coverage likely increasing on Saturday. END UPDATE
UPDATE 8:30 AM: FLASH FLOOD WATCH EXTENDED TO 8AM SATURDAY. Don’t be surprised if it’s continued beyond that, perhaps throughout the weekend. The National Weather Service in Blacksburg notes that it is so saturated, rainfall amounts as little as 1 inch may cause flash flooding in some areas. END UPDATE
Canadian cold fronts just can’t cut through tropical soup in July.
Our hopes of having a relatively cool, dry intermission in the pattern of showers and storms are fading. A weak cold front is pushing through as I write this late Thursday night — it’s the reason for this nocturnal line of showers and storms that blew up along the I-81 corridor and is sliding southeastward. There is plenty of unseasonably cool, dry air back out toward the Upper Midwest and Ohio Valley. But it’s going to have a hard time displacing this thick tropical juice that has been blown in from Caribbean and Gulf of Mexico. The front will not make much progress east of us (maybe as far as the map at left shows), and will begin to wash out and/or back up through the weekend. Expect to see some showers and thunderstorms again developing in the afternoon on Friday in Southwest Virginia, and likely more of them Saturday and Sunday. The moisture we’ll see over the weekend may be enhanced some by whatever is left over from the former Tropical Storm Chantal. With saturated soil and the potential for locally heavy rains, flash flooding is going to be possible anywhere the bigger storms develop, especially where bands of them move over the same areas repeatedly.
The best hope for getting to a somewhat drier state (besides moving to Arizona) now is with another westward expansion of the Bermuda high next week. An upper-level low just west of us will eventually get bounced west — really far west, perhaps all the way to about Oklahoma. That may take some of the moist flow with it and put us under drier, calmer air aloft. There is so much moisture built up at the surface, though, and nothing to really scour it out, that we’re not going to lose at least some chance of afternoon showers and storms anytime in the near future.
This is just what summer 2013 is going to continue to be … soupy.