Those rumbles, gusts and downpours you may have gotten a time or three last Thursday through Sunday — that was autumn landing body blows on summer.
Let’s be clear: Summer hasn’t been knocked out. Considering how hot it still is in some other parts of the country, it’s not even “on the ropes” yet. But for Virginia, summerlike heat has been stunned and will need some extraordinary efforts to fully recover against the tide of shortening days and lowering sun angle.
A mass of cool, dry air from Canada began punching into some of the hottest weather we had experienced since mid-July last week. The two tangled a few days as a front got stuck and the air got sticky, leading to intermittent rounds of thunderstorms with some streaky heavy rain and spotty gusty winds. (Most of the photos with today’s weather column will illustrate these storms, as many interesting ones were posted by regional residents.)
By late on Labor Day, the cooler, drier air took the round, and generally looks to hang on for most of the first half of September in much of the eastern half of the U.S.
Wednesday morning began with 40s and 50s low temperatures across the Southwest and Southside Virginia coverage area of Cardinal News with highs expected to stay below 80 just about areawide. Temperatures will be similar on Thursday then nudge up by Friday and Saturday with some lower 80s in the lower elevations of our region, but over the weekend, another cold front will push through and reinforce the cooler temperatures and lower dew points, carrying us into next week.
The weekend front may kick up a few showers and thunderstorms on Saturday, but widespread weekend washout type rain is not expected. That will be good for football games and post-Labor Day outdoor gatherings, but the dryness will become an issue again pretty quickly for our region if we don’t get some general rain in the next couple of weeks. Many locations have gotten substantial rain at various times in the past six weeks, but none of the rainy episodes have been entirely areawide or evenly spread.
While it’s almost inevitable that at least somewhat hotter weather will resurge at some point later this month, perhaps bulging back in from the western states, and take us back at least into widespread 80s for a few days, I’m hesitant — again — to call this a “false fall.”
When we had some unseasonably cool weather in August, my description was “fall preview” rather than “false fall” that was prominent on the internet. My argument then was that we already knew there was no chance a cool spell in August was the start of “real fall,” so there was no point calling something “false” that couldn’t possibly be the real thing to start with.
With what is happening the next couple of weeks, this definitely has more the feel of an early or preliminary stage of the seasonal autumn cooldown, rather than anything “false.” It’s the first real and fairly long-lasting step to putting summer 2024 in the rear-view mirror.
It’s likely not going to stay cool straight through to October, but by the time this cooler spell relents, we’ll be that much farther along with shorter days, lower sun angle, and jet stream patterns sinking south over the Northern Hemisphere, and it will be that much harder to maintain a hot spell. Never say never — early October 2019 found a way to almost hit 100 at multiple locations across our region — but the odds for prolonged or extreme heat are getting longer with little chance of either through the first half of September.
I often receive “get-and-stay” questions as seasons change, as in “When is it going to get cool and stay cool?”
The problem is, we rarely have “get-and-stay” weather in any season.
This past summer’s heat was more intense and stubborn than we’ve seen in recent years, but even that didn’t stay past mid-July except for a couple of short not-quite-as-hot spurts early and late in August. I don’t have to tell anyone in our region that we haven’t had anything since arguably January 2022 and maybe even more like 2014-16 that would resemble “getting cold and staying cold” in the winter.
Autumn tends to cool down in fits and starts rather than ever “getting cool and staying cool.” Consider this a start or the first fit.
But it has to be encouraging to lovers of pumpkin spice, flamboyant foliage and sweater weather that since extreme heat wilted in July we are now basically on our third round of “western ridge, eastern trough” pattern that has centered the hottest weather somewhere out West and funneled cooler air out of Canada toward us. Snow lovers should hope these patterns become a habit past Christmas.
Star City sizzle
Roanoke’s summer average temperature of 78.2 degrees tied 2010 for hottest summer on record in 113 years of data, as figured by the National Weather Service.
For weather statistics, summer runs June 1 to Aug. 31, keeping the three hottest average months of the year together. This is sometimes called “meteorological summer.”
The summer looked like it might be a runaway winner through June and July, but some cool spells in August — lows of 50 on Aug. 21 and 22 were Roanoke’s coolest consecutive mornings lows in August since 1989 — dampened the average for the summer quite a bit.
Eight of the nine warmest summers on record for Roanoke — the average of highs and lows for all 92 days June 1 to Aug. 31 — have occurred since 2007, and three of the five warmest have occurred since 2020.
In the big picture of climate, global warming trends are raising average temperatures on much of the planet. In the small picture of seasonal weather, this particular summer contained the most extreme heat waves our region has experienced in a dozen years. But neither of those can fully explain why the Star City seems to be running a much higher fever than other similar regional sites.
With periods of record dating even farther back than Roanoke’s 1912, all the way to the early 1890s, this summer was tied for the 12th warmest summer on record at Blacksburg (72.0) and was tied for 14th warmest at Lynchburg (76.5 degrees). Blacksburg and Lynchburg have each had six of their 20 warmest summers since 2010, but both sites’ top three warmest date to the first half of the 20th century.
So, while the data shows evidence of this having been a hot summer relative to history and for warmer summers becoming more frequent at Blacksburg and Lynchburg, the numbers don’t show either having happened to the same level as the city in between them on U.S. 460.
It’s important to note that it is warmer nighttime low temperatures, more than extreme summer high temperatures, that have been driving the summer temperature spike for Roanoke. Most of the recent summers with warm averages did not have 100-degree days or long stretches of 90s, but they did have muggy nights. Prior to 2002, Roanoke had never had as many as 26 days in summer with a low temperature at or above 70 degrees. But since then, 13 summers, more than half, have had that many or more days with lows 70 or higher.
My working theory for years has been that the sensor site at what is now called the Roanoke-Blacksburg Regional Airport has become increasingly surrounded by urban development — shopping centers and parking lots — whereas it was largely meadows and pastures in most of the 20th century. So heat is held in by concrete and asphalt at a greater rate and radiates at night, slowing temperature fall overnight. But there could be something atmospheric or geographic I’m missing.
One of the biggest upsets this year was that among the 16 sites chosen for the Cardinal Weather heat prediction contest, Roanoke tied for hottest temperature of the summer at 103 degrees with the perennially hot John H. Kerr Dam in Mecklenburg County. Of all my picks for the hottest temperature at the 16 sites, Roanoke was the only one I underestimated in my predictions.
Which brings us to this: We’ll be revealing the winners of the summer heat prediction contest in the next week or two, and it will be snowfall prediction contest time before we know it.
Journalist Kevin Myatt has been writing about weather for 20 years. His weekly column, appearing on Wednesdays, is sponsored by Oakey’s, a family-run, locally owned funeral home with locations throughout the Roanoke Valley. Sign up for his weekly newsletter:
