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The Storm Prediction Center has placed all of Virginia under a slight risk of severe weather today. By afternoon, as heat builds, it will push moist updrafts into cooler air aloft, which could trigger thunderstorms. The best chance for severe weather, with large hail and high winds, is likely to be be east of the Blue Ridge, where wind conditions through the atmosphere, instability and moisture are more conducive to thunderstorm development. But a cold front hanging to our west could be another trigger for thunderstorms, and cold air will be even lower in the atmosphere there, so storms could have a better chance of producing hail. Daytime heating, the mountainous terrain, and any leftover outflow boundaries from storms during the evening can also help storms develop today. It's a rather complicated situation that could yield some more reports of hail and strong winds, though it appears now that the coverage of storms may be less than Sunday. After today, drier weather will move in for a few days, with temperatures warming back to near normal by late in the week (upper 80s for highs, lower 60s for lows in Roanoke).

This photo from Jesica Clements shows a jagged, roughly quarter-sized hailstone that fell near Wasena Park in Roanoke

Steep lapse rates ... a rapid change from warm air near the surface to cold air aloft ... led to several reports of large and/or prolific hail today. The National Weather Service in Blacksburg received at least one report of hail 4 to 6 inches deep on the ground near Galax. Much of Roanoke also experienced hail up to an inch in diameter in a mid-afternoon thunderstorm. Here are a couple of quick links to a video and photo showing some of the hail.

Another storm about 8:30 p.m. at Blacksburg produced large hail up to 1.5 inches in diameter. The storm exhibited some weak rotation on radar as it moved through Giles and Montgomery counties, but then became dominated by outflow winds and weakened as it moved toward the Roanoke Valley and points eastward.

Hailstorm video from LoLo Monae of Roanoke

Hail covering front porch by Josh Jackson in Roanoke

My photo of a multi-tiered shelf cloud moving over Salem about 1:45 p.m.

Hail covering a walk way by John Jackson in Roanoke

William Ingram uses a snow shovel to remove hail in Blacksburg, submitted by his father Hank Ingram

In the extended entry below is a long list of severe weather reports across the area from the National Weather Service in Blacksburg. You can also click here to see a listing and map of severe reports nationally from the Storm Prediction Center.

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The relatively cool air mass that has settled over us the past few days is slowly moderating. We will probably see highs more in the low to even mid 80s in Roanoke over the weekend into early next week rather than in the 70s. So, with lows around 60, temperatures will be just about where they should be this time of year, maybe a hint cooler. The slightly cooler air will get a little bit of a reinforcement over the weekend, and that could be enough to trigger some thunderstorms as it clashes with somewhat warmer, more humid air over us.

(By the way ... Rick Post of Wytheville pointed me to some automated thermometer readings between Rural Retreat and Wytheville in the low 40s each of the last three mornings ... now that's chilly for June!)

Longer term, from about this time next week onward, it appears likely that truly hot weather will develop again in our neck of the woods. The Climate Prediction Center gives us a better than 50 percent chance of above-normal temperatures 8 to 14 days out, with hot weather starting to build in the Southeast and mid-Atlantic 6 to 10 days out. High pressure is expected to slowly take the place of the low-pressure trough over the East that has drawn down cooler air from Canada. So, yes, the hot weather is coming back, like it or not. You shouldn't be too surprised. July is not far away.

Wednesday's low was 53 in Roanoke, 49 in Blacksburg. Roanoke made it at least as low as 56 this morning, while Blacksburg again dipped into the upper 40s, at least as low as 48 at Virginia Tech's airport.

Below-normal temperatures are going to continue through early next week. Highs today and Friday may reach the low 80s in Roanoke. The normal high is 83, so that would be no better than normal. By the weekend, a reinforcing shot of cool air is due to arrive from Canada, pushing highs back down into the 70s and lows back into low to mid 50s, with some 40s to the west of Roanoke. The cool pattern will only slowly unwind next week, as more typical June warmth and humidity return.

Lows are projected in the low to mid 50s for each morning from Wednesday to Friday in Roanoke, possibly into the weekend. Lows could even be cooler in more rural mountain and valley areas.

Roanoke's record lows for the next three mornings are 46 for June 18, set in 1959; 48 for June 19, set in 1999; and 53 for June 20, set in 1935, 1954 and 1965. So as you can see, Friday would have the best shot at a record low in Roanoke. Record lows are unlikely both Wednesday and Thursday.

Normal lows are about 60 this time of year.

Most of Monday's bigger storms were farther north. According to some reports, hail covered the ground like snow in areas to the north of Charlottesville, and there were numerous wind damage reports. Here's a listing of Mondayh's severe weather reports from the Storm Prediction Center.

Today's high in the low 80s in Roanoke could well make this the warmest day the rest of the week, with temperatures struggling to make 80 the rest of the week. Enjoy it ... while the unseasonably cool weather is likely to last several days, we all know that torrid summer heat will return sooner or later.

In order to get some cool air later this week, we've got to get through a threat of severe thunderstorms today and tonight, and a pretty serious one at that. The Storm Prediction Center has raised a moderate risk of severe weather for most of Virginia north of the Roanoke Valley, with a slight risk elsewhere. The threat today is largely the result of cold air aloft, which will enable warmer and increasingly more moist air to rise into that cold air aloft. This could bubble up some big thunderstorms today, aided by the cold front moving southeast, lifting warm air upward. Strong winds and hail will be the biggest threats; the winds are mostly blowing in the same direction in the different layers of the atmosphere, so tornadoes will probably be few and far between, if any occur at all. Unfortunately, it looks like another day of spotty rain, where one place may get a couple of inches while another not far away gets sprinkles, depending on how the storms develop. The front will push through overnight into Tuesday, and unseasonably cool weather will settle in much of the rest of the week, with higs in the 70s and lows in the 50s, with some 40s, through the weekend.

As expected, strong winds and heavy rain were common in thunderstorms that occurred Saturday, though there were a handful of pretty large hail reports, too. Today should see much less shower and thunderstorm activity,as a weak cold front has pushed through, but there could be more again on Monday as a much stronger cold front arrives in the area. That front will be the leading edge of a major pattern change that will bring unseasonably cool weather to the area later this week.

The extended entry below contains severe weather reports in the area from the National Weather Service in Blacksburg.

Read more »

The combination of daytime heating, lingering humidity, terrain effects and an approaching cold front may trigger some strong to locally severe storms in Southwest Virginia this afternoon. Upper-level winds are not that strong, so widespread severe weather and rotating storms capable of large hail and tornadoes are unlikely. But some storms could unleash damaging wind gusts in small areas or kick out some small hail, and many storms will unload some torrential rain on localized areas while places not far away remain dry. The Storm Prediction Center has issued a mesoscale discussion for much of western and central Virginia today for this severe weather threat, but says that a severe thunderstorm watch is not anticipated.

In Iowa, they've had far too much rain. A Roanoke-sized city in eastern Iowa, Cedar Rapids, has much of its central business district under water. It's all part of a seemingly continuous pattern of heavy rain and severe storms that has raked the Plains and Upper Midwest.Click here for the latest from the Associated Press.

The problem is the reverse in our region, where wildfires in both North Carolina and Virginia, including one on Poor Mountain, are burning vegetation and smoking up the air.

While the most severe drought is a little to the south of our area,, over the western Carolinas and northeast Georgia, the Roanoke and New River valleys and points south are considered to be in moderate drought.

It does look to get much cooler next week, but not a lot wetter. The principal rain threats the next several days will remain in the central part of the U.S
I'm beginning to wonder if we're going to need a tropical system to help soak things, starting with the massive wildfire in eastern North Carolina.

In the meantime, the wind flow the next couple of days is likely to change enough to blow away North Carolina's smoke. Then, we'll only have our own to deal with.