Southwest Virginia part of a large-scale disaster on Friday night; more heat Saturday, possibly some storms
UPDATE 9 AM: Southwest Virginia east of Interstate 77 is once again within a slight risk zone for severe storms today and this evening … and on Sunday as well. The threat is similar, with the potential for 1 or more strom clusters or “bow echoes” producing damaging winds, but at this time, it is especially focused on central and eastern Virginia, where the outflow from storms currently ongoing near the Great Lakes will push over the Appalachians, interact with extreme heat and higher humidity and potentially trigger a new round of storms. It is possible our region could be on the western side of that storm complex, or catch a new storm complex developing from a small cluster in Iowa this morning. It will simply be a matter of monitoring radar and seeing how and when any storms develop.
Meanwhile … a heat advisory is in effect for the Roanoke Valley eastward for a heat index topping 100 degrees. With lots of sunshine, highs may end up similar to Friday’s, perhaps shaving a few degrees just simply because we’ve started this morning much cooler.
Roanoke’s high temperature for Friday has now been confirmed at 104. That ties June 30, 1936, as the hottest June day on record, and puts June 29, 2012, among only a dozen dates in Roanoke history back to 1912 that reached 104 or 105. The all-time record of 105 was set 3 times: July 10, 1936, Aug. 5, 1930, and Aug. 21, 1983. END UPDATE
The numbers are staggering early on this Saturday morning — an estimated 3.5 million without power (and growing) from an especially intense and long-lived derecho event — a windstorm generated over a large distance by a bowing line of thunderstorms. The map at left (full version linked here) shows a blue dot for each wind damage or severe wind speed (58 mph+) report … and a black square for anything over 75 mph, including one right over Roanoke Regional Airport, where an 81 mph gust was clocked. There are also some reports of fatalities coming in from various states affected by the storms. It will be many days before power is restored in full from Indiana to the Atlantic shore – many hot days. Highs on Saturday are likely to again climb into the mid 90s to near 100 across much of Southwest Virginia after record-setting numbers on Friday (Roanoke’s high may have in fact reached 104, 1 degree higher than previously reported – will update later today once it’s confirmed one way or the other). It’s hard to factor exactly what effect Friday night’s windy storms will have on Saturday’s temperatures, but the atmosphere is primed for another extremely hot day, if clouds and/or storms don’t intervene early enough. And that’s going to make it tough on all who have lost power, who will be suffering without air-conditioning in extreme heat, and many who are outside working on power lines or clearing trees in that heat. Definitely a time for neighbors and friends to help each other out.
There is a chance of more storms on Saturday afternoon and evening. In fact, as I type this, new storms are forming near Chicago, close to where Friday’s derecho started. As of this writing, storms are expected to be focused more to our north — regions that were hit hard enough already by the same storm system that whacked us. Follow the Storm Prediction Center for the latest outlook on severe storm potential.
A June that for the most part has been a pleasant and even rather cool month in Southwest Virginia certainly isn’t ending that way.