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Photo by The Associated Press -- A home was destroyed along a lake in Deerfield, N.H.

File this away in the "Tornadoes can hit there, too" department. Almost no one thinks of New Hampshire and tornadoes together. But on Thursday, a tornado ripped through 9 New Hampshire towns, killing a 57-year-old woman who was trapped in a collapsed house. According to an Associated Press article, the EF-2 tornado (winds of 111-135 mph, rated on a scale from EF-0, 65-85 mph winds, to EF-5, 200-plus mph winds) tore through Deerfield, Epsom, Barnstead, Alton, New Durham, Wolfeboro, Ossipee, Effingham and Freedom. At least 6 homes were destroyed and hundreds were damaged.

Photo by The Associated Press -- An aerial view of the flattened home above.

Tornadoes are not as unusual as it might seem in New England. The June 9, 1953, tornado in Worcester, Mass., killed 94 people. The severe weather threat peaks in that region from June to August, when temperatures warm up enough to destabilize the atmosphere, and the jet stream sometimes roars overhead, capable of spinning some storms into supercells, which in turn can spawn tornadoes when a rotating updraft becomes sufficiently intense and stretched to the surface. Conditions were very favorable for such rotating updrafts in New England on Thursday. It was part of the same system that brought us severe weather earlier this week, but closer to surface low pressure supplying stronger low-level winds and under much stronger winds aloft.

It might be hard to believe for the folks in Botetourt County who got 3-5 inches of rain on Tuesday, but according to the latest map from the National Drought Mitigation Center in Lincoln, Neb., most of Southwest Virginia remains in light to moderate long-term drought. One caveat: This was based on data through Tuesday morning, before the heavy rains came. A summer of frequent thunderstorms has eroded the drought area some, but the spotty nature of the rains has not allowed widespread alleviation of the drought. Everytime somebody gets creek-choking rains, someone a few minutes down the road is not getting enough rain to settle the dust. And the week before the most recent scattered downpours was mostly dry.

A weather pattern that appears to be building in over the next 7-10 days may give us several chances for additional rainfall, though mostly in the form of showers and thunderstorms rather than a much needed slow, areawide general rain. Upper-level low pressure developing near the Great Lakes appears poised to force the jet stream southward over the eastern U.S. many of the next several days. This will supply a steady diet of cold fronts and upper-level disturbances running into the warm, moist air from the Gulf of Mexico. The Climate Prediction Center rates Virginia as having a better than typical chance of above normal precipition in the 8-14-day period.

Though any sunny day will be able to push temperatures into the 80s or even low 90s, and increasing humidity will at times buoy nighttime temperatures at levels that may be a little above the norm in the mid 60s, the overall trend of temperatures with a jet stream pattern dipping southward is likely to be somewhat below normal as cold fronts from Canada snub the heat and hot high pressure from the west is prevented from building eastward. The CPC's maps reflect this possibility in both the 6-10-day range (cooler than normal temperatures favored over most of the East) and in the 8-14-day-range (confined more to the Southeast)

In the other seasons, it's usually an above-normal temperature period that carries the higher risk of severe thunderstorms, but in summer, it can actually be cooler-than-normal periods. That's because, in summer, hotter than normal weather usually reflects expectations of a large high pressure dome building in, which can put a cap on any storm-firing convection, while cooler-than-normal periods reflect passing cold fronts and an unusual amount of upper-level wind for what is typically the most stagnant time of year.

I fully expect a few more rounds of gusty thunderstorms during the next couple of weeks as this pattern unfolds. But we may get one more warm but mostly dry day in on Friday before the moisture gets thick enough again for afternoon storms.

The cold front has pressed through and, after two storm days, should leave us a dry day on Thursday. Hurricane Dolly is inland and was recently downgraded to a tropical storm, though it will still rain a ton on both sides of the Rio Grande Valley. But there are no other systems that are expected to develop into tropical depression in the Atlantic for at least the next couple of days.

How about we take a short breather from active weather.

A menacing shelf cloud advances over Roanoke at the leading edge of strong storms about 4:30 p.m. Click here for a bigger look.

It happened, again. A band of strong to severe thunderstorms worked through the New River Valley with numerous reports of large hail, and then blew through the Roanoke Valley between 4:20 p.m. and 5:30 p.m., with some gusty winds, heavy rain, frequent cloud-to-ground lightning and perhaps some scattered small hail. As the storm system advances eastward, expect heavy downpours, gusty winds and some robust lightning most everywhere these storms pass over, with some locally very damaging winds (60 mph-plus) and hail possible.

I took a series of photos from the Roanoke Times roof garden as the storm arrived. Where I was, the winds peaked at no higher than 45 mph, and I observed no hail, but the shelf cloud soaring over the city was an awesome sight. One of my photos is inset above, and several more are linked below:
* Shelf cloud approaching
* Outflow boundary over downtown
* Lowering to the southwest
* Flags extended by wind on Higher Education Center

M.L. St. Clair shot photos of the storm's outflow rolling over the Roanoke Valley

M.L. St. Clair of Salem submitted a pair of photos showing angry storm clouds, looking toward Roanoke.
* Salem storm photo 1
* Salem storm photo 2

If you have photos from this afternoon's or evening's storms that you don't mind me using on the blog, please email them to me. If you have any notable observations on the stormy weather, either email me or comment below.

Just like last night, a severe thunderstorm watch has been issued for Western Virginia until 11 p.m.

Latest warnings and watches via National Weather Service-Blacksburg Web site

Latest National Weather Service radar

Storm reports from the National Weather Service:
* 3:15 p.m. -- 8-inch-diameter tree limb blown off tree, Radford
* 3:39 p.m. -- 1-inch hail, falling for 5 minutes, Fairlawn, Pulaski County
* 3:40 p.m. -- .88-inch hail, Radford, trained spotter report
* 3:40 p.m. -- 1.25-inch hail, covering the ground, lasted 10 minutes, Fairlawn, Pulaski County
* 3:50 p.m. -- .88 inch hail, Radford, public report
* 3:55 p.m. -- 1-inch hail, Christiansburg
* 3:55 p.m. -- Large tree blown down, Christiansburg
* 3:55 p.m. -- 1-inch hail, lasted 5 minutes, 2 miles west of Christiansburg
* 4:45 p.m. -- Large tree blown down at Windy Gap, 4 miles southeast of Roanoke
* 4:54 p.m. -- Large tree blown down, 3 miles southeast of Roanoke
* 5:45 p.m. -- .75-inch hail, 2 miles northeast of Snow Creek, Franklin County

A cold front is pushing into our warm, moist air today, and that is likely to trigger a new round of thunderstorms as we move deeper into the afternoon and evening. At mid-afternoon, the Storm Prediction Center issued a mesoscale discussion (an alert a step below a watch, often preceding one) highlighting western Virginia for a heightened risk of severe weather (linked here). The inset radar image shows a band of storms moving out of West Virginia toward us in association with the front. We will also need to watch out for storms developing ahead of the line. It was clusters of storms like that which caused much of last night's mayhem in some areas. West winds at the surface, blowing downslope, may keep a damper on things for a while today, and it appears the worst threat of severe weather may be to our east today -- a severe thunderstorm watch is already out for eastern Virginia. Still, expect to see some storms with gusty winds, hail, heavy rain and frequent lightning. As with last night, everybody won't get all that, but some folks will got a lot of it, as parts of Botetourt County did last night.

As always, e-mail me or post a comment on this blog if you have any significant weather reports during any storms today.

Latest National Weather Service radar linked here

On the extended entry below is a listing of all the severe weather reports turned in to the National Weather Service in Blacksburg from Tuesday night's storms:

Read more »

Satellite photo of Hurricane Dolly, courtesy of National Hurricane Center. Click here for bigger look.

Hurricane Dolly pumped up quite a bit overnight. It's now a Category 2 hurricane with winds about 100 mph. It has been lashing the south Texas coast with heavy squalls of wind and rain for hours, and there has already been some damage. It appears to be coming in a little north of Brownsville, which means that much of its worst fury will be focused on South Padre Island, a popular vacation destination. But that doesn't mean it won't still be a rough ride for Brownsville just to the south or even Corpus Christi several miles to the north. Dolly will likely drift westward inland, slowly dumping a ton of rain.

Click here for the latest from the National Hurricane Center

I will also soon have an update on our own local severe weather potential.

William Mahone sent in this photo of lightning from Roanoke County just north of the city looking toward Tinker Mountain. Click here for a panorama-look at his photo.

Tuesday' evening's thunderstorms brought scattered reports of damaging winds, hail up to quarter-sized, frequent lightning and torrential downpours. The storms put out lots of moisture and laid down outflow boundaries that could come into play triggering a new round of thunderstorms today. The focus for more of the severe weather will shift east, into Piedmont east to the coast, but depending on how much early sun we get, when the cold front pushes in, and how an upper-level disturbance interacts with the moisture, we could again get some gusty storms with hail again today. It seems we are back in the familiar stormy pattern of this summer. We'll get a couple days break in the storminess after today, but may well resume it for the weekend and into next week.

Contrails stand in contrast to a growing storm cloud north of Roanoke. Click here for a bigger look.

Thunderstorms have popped up this evening in just about every direction around Roanoke, though none have yet to really hit the core of the Roanoke Valley head-on. A couple of severe thunderstorms have skirted around the north edge, with 3/4-inch hail reported at Daleville at 8:30 p.m.. Earlier in the evening, trees were reported blown down at Montvale and .88-inch hail occurred at Thaxton, both in Bedford County, as a storm developed just east of the Roaoke Valley. Other severe storms have developed south of Roanoke in Southside Virginia. Many of these storms developed east of the severe thunderstorm watch box, which is why the wording of watches always says "in and close to the watch area." The bigger concern for the New River and Roanoke Valleys is whether a cluster of storms that was near Bluefield, W.Va. just before 8:30 p.m. will hang together as it approaches Blacksburg and Roanoke in the next 2 or 3 hours. UPDATE 9:40 PM: This cluster did not hang together well, but a new cluster of storms formed after 9 p.m. in the Roanoke and New River valleys.END UPDATE

As always, if you have your own storm reports, either e-mail me or comment below. Also e-mail me if you have any good photos of the storms or storm-related damage.

Click here for the latest from the National Weather Service in Blacksburg.

We may have our own home-brewed severe weather to watch tonight and Wednesday, but it's worth noting now that Dolly has been upgraded to a minimal hurricane with 75 mph winds. It is expected to make landfall very near Brownsville, Texas, which lies at the southernmost tip of the continental United States at the mouth of the Rio Grande. So whether this becomes just the second U.S. landfalling hurricane in 3 years depends on which side of that border its eye comes ashore on.

Click here for the latest from the National Hurricane Center

The Storm Prediction Center has issued a severe thunderstorm watch for Montgomery and Floyd counties and points west until 11 p.m. tonight. Storms are firing in Kentucky and Tennessee and some of these may charge eastward as the evening progresses. How far east they get is the questionable, but it bears watching even for the Roanoke Valley. High winds will be the biggest threat from this evening's storms.

Click here for the latest from the National Weather Service in Blacksburg