UPDATE 12:20 AM, 8/8: No major changes. Some locations from Roanoke south and east might scrape 90 Wednesday and Thursday. Friday may be a stormy day, with severe weather possible, as the cold front cuts into the thick humidity. I will follow up on this in later blog entries. Meanwhile, here’s something else to chew on: Wednesday’s Weather Journal column about the lack of tornadoes in the U.S. this year, especially since mid-April. END UPDATE
A cold front is sinking through our region overnight and Tuesday, bringing somewhat cooler air, though not much less humid. Showers and storms were not as widespread as projected Monday, but there could be some showers and storms any day this week, though the chances will better to the south and east in thicker moisture, at least through Wednesday. Highs will mostly stick in the 80s this week — though Tuesday will probably be more like mid 70s to low 80s, similar to Monday’s 76 at Blacksburg.
In the bigger picture, there are certainly some signs that the vicious central U.S. heat dome may be starting to lose its grip. It is backing up into the western U.S. the next several days, with a southerly dip in the jet stream digging into the Great Lakes and Northeast. That may be enough to allow the strongest cold front since June )before the heat wave and derecho) to slide through by the weekend. Forecasts are going to hedge toward the typical seasonal pattern of the front getting hung up and not making a clean push through, but if it can slip through as some models show, a day of widespread 70s highs/50s lows would be within the realm of possibility. Beyond the 6-10-day period, there is little model agreement on where the weather pattern will go. The Climate Prediction Center favors a low probability of above-normal temperatures for much of the East in its 8-14-day outlook, with the heat dome vacating the central and western U.S. entirely, but the CPC also notes a confidence level of 1 on a scale of 1 to 5 in that forecast. Model confusion in the long range is sometimes a signal of drastic changes in the weather pattern, but keep in mind that this is August, when quick and large changes usually do not occur so rapidly, especially with such a large-scale heat wave and drought under way over much of the nation. We can’t be sure yet whether much of August will end up being cooler than normal for us or at least seasonably hot, but for now, it remains obvious that the 100-degree stuff — and even most of the 90-plus stuff — will be staying away from Southwest Virginia throught at least the next week.