UPDATE 2 PM: Tornado watch issued; severe storm risk for all of Virginia today, but greater to east of Roanoke
TORNADO WATCH UNTIL 9 PM FOR ALL OF WESTERN VIRGINIA
A cold front is pushing into warm, moist air ahead of it today, with some degree of shifting winds aloft. That is a recipe for a substantial severe weather threat over the state of Virginia. There are some uncertainties in that seemingly straightforward forecast. One is the current showers and cloudiness over much of Southwest Virginia that could limit warming and therefore destabilization of the lower layers of the atmosphere. Also, as the National Weather Service-Blacksburg points out in its morning discussion, there may be a chance of the “Blue Ridge jump,” where a storm line forms far to the west and then re-forms east of the Blue Ridge, with the stronger storms skipping over some or all of the New River and Roanoke valleys. All that said, there is enough lift with the cold front and certainly enough moisture that strong to severe storms will be a significant possibility during the afternoon. Strong downburst/outflow winds will be the greatest severe risk for Southwest Virginia, as shown on the Storm Prediction Center’s morning map rating the chance as high as 30 percent of occurring within 25 miles of any given point. The tornado risk is greater mostly north and east of our region, owing to somewhat better atmospheric shear and greater instability with more daytime heating. There will probably be a few tornado reports in central/eastern Virginia later today, though a large tornado outbreak on the scale of those of April 2011 does not appear to be likely. The pattern is more that of a strong summer severe setup rather than a spring outbreak. The more the sun shines at your location and the farther east you are, the better your chance of high winds, large hail and isolated tornadoes in storms today.
Being in the field with the Virginia Tech storm chase in the Oklahoma/Texas panhandle region -- the only other slight risk of severe weather on the Storm Prediction Center’s map today, where coverage will be much less than Virginia but the potential for supercells higher — I will be unable to provide ongoing updates today. You can follow radar and the latest watches and warnings on the Radar / Future Cast link in the right margin of this blog.
June 1, 2012 - 9:10 AM
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Thanks for the new thread, KM. To follow up what Nate posted on the most recent comment (last comment on the previous thread), we have low clouds here in the Roanoke Valley and absolutely no sunshine yet. I bet the immed. Roanoke Valley gets no severe weather today, and I also agree with the NWS-Blacksburg office, that there is going to be a major Blue Ridge jump.
If any of you live in Bland, Giles, maybe western Craig and NW Montgomery counties (near the Giles County border), you may get some strong/severe storms, and maybe Wythe county, too. I bet the chances drop way off east of those locations until you get east of the BRP, and perhaps well east and especially NE of the Parkway.
“7″‘s forecast model showed the biggest, strongest storms way up in the I-95 corridor, mostly well north of Richmond (Fredericksburg and within 40 miles of there, roughly). Also Northern Neck of Virginia. And those would be hitting there this evening, as I remember it. We will see how it all plays out. But I remember from learning years ago here that we would have a much bigger chance of strong/severe locally if we were having a bright, sunny morning with all this humid, (potentially) unstable air.
One extraneous weather note: The North Atlantic Oscillation is projected to take an extreme dip into negative territory, meaning greater high pressure near Greenland forcing the jet stream more to the south.
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif
In winter, this would just about assure a major cold outbreak. In late spring/summer, the correlation is not as strong, but the extreme nature of it may be enough to lean the eastern U.S. toward northwest flow out of Canada as we go into June, possibly leading to at least somewhat cooler than normal weather. Something to keep an eye on.
It sound like, based on your last post, that the summer may not be as scorching hot as I believe.
10:51 The sun just broke through the clouds, but it looks like a shield of heavy rain is knocking at the door. Wind is rather brisk out out the south east at about 15-20MPH.
a line segment coming to a town near you!!
Here is convective outlook for today…graphic included.
http://www.spc.noaa.gov/products/outlook/day1otlk.html
line to watch now is the one running from Rainelle to about Knoxville..
individual cells are moving to the NE at 20-30kts,,,they are quick movers.
Starting to organize a bit better around Rome Ga too..watch this line for development.
Agree with Joe. Was going to note that myself before he did.
We’re in a holding pattern at the Guymon, Oklahoma, hotel we’re staying at since it looks like storms won’t be too far from here today. I’ll keep posting comments as long as I have good Internet here. Once we’re on the road, I’ll have roanoke.com staff approve comments from time to time to keep the conversation going today. My smartphone connectivity is zilch out here, so I may not tune in much for a few hours.
We’ll be watching Virginia some too even as we’re out here. Many of the students get weather warnings from Virginia automatically on their phones.
Thanks, “Professor,” for the comment about the upcoming dip in the NAO. I, on the other hand, am very hesitant to declare a cool summer based on a possible/probable cool spell in the first half and maybe extending into the middle of June. I would actually be more encouraged if we had a brief hot spell with a very positive NAO and AO now, because I think that would (greatly?) increase the chances that those oscillations would start declining in late June, July, and possibly even into August. I think my research a couple of weeks ago revealed that was the scenario in the summers of 2000 and 2003, although declining oscillation values do NOT guarantee anything about our temps here.
But who knows?? We just had an epic continuous monthly streak of positive NAOs … maybe we will have a long streak of negative NAO and AO? Even I would get “optimistic” then.
Meanwhile, I am sticking with my outlook for the Roanoke valley for the next 18 hours. I am sure that we will get at least a little rain, but I doubt any severe stuff. It is still very cloudy, and the temp is about 68*. Now if it were 100% sunny and in the 80s ….
I’m having a feeling, given the strong easterly breezes and thick cloud cover, that severe storms that impact the NRV will not be developing in the area, but developing further south and west and just plowing into the mountains.
SPC has upgraded the DC area to a moderate risk of severe weather with a 15 percent zone for tornadoes.
http://www.spc.noaa.gov/products/outlook/day1otlk.html
No significant change to the status for Southwest Virginia.
SPS has moved parts of Virginia into moderate risk of severe weather.
http://www.spc.noaa.gov/products/md/md1003.html
Heavy rain and storms are affecting the uva baseball game in Charlottesville. They got half an inning in before a delay, took the tarp off, got the field ready and now in another delay.
The storm north of Bedford is really starting to blow up. It’s going to see how this storm grows without any other storms near it to interfere with convection and outflow. Looks like all of the storms are moving slowly n/ne.
Tornado warning for Nelson/Amherst
Nate, that storm now has a Tornado Warning going in Amherst County.
Tornado watch just issued — actually 2 watches covering most of the state.
Anything that develops ahead of the squall line will have a better chance of remaining “discrete” with possible rotating updrafts that could to lead to large hail, very strong winds and perhaps a few tornadoes. Several of these cells seem to be developing east of the Blue Ridge.
Starting to see cumulonimbus clouds climbing in our sky, too — so may be on the road soon for a storm chase even as severe situation develops in Virginia.
The newest radar frame just caused my hair to stand on end regarding the Nelson storm. Holy crap
CCFP shows back edge of band moving through about dark…
Shows not so much support for higher tops,
and heights dropping off north of Mason-Dixon..
Tops should only be 30-35000ft SWVA..probably no hail
and just some pockets of hard rain.
Max tops in Western Okla 39000 feet too..
Not as much widespread activity in OK…
But CCFP shows the area almost stationary
once it fires up.
pic of tornado this afternoon in Sterling..Northern Va.
http://www.wusa9.com/news/photo-gallery.aspx?storyid=207176
Wow – wind suddenly picked up and raining sideways here on Virginia Tech campus.
Trevor here in Christiansburg, reporting fierce winds, eyeballing it at 30 mph, minimum. I wouldn’t be surprised if there are going to be downed trees and power outages. I could literally see the squall line coming toward me from the southwest (standing in front of my backyard facing a pasture toward the old Life Bible College east campus, now the Bridge Worship Center church).
That should be the last precip band Trax…
clears out fairy nicely west of the Burg..
Throw on a blanket tonight.
Brent Watts of WDBJ7 is just now announcing a tornado warning for the southern half and central Rockbridge County. Currently in an area called Buffalo Bend, right on I-81, and the southern environs of Lexington, Buena Vista, and Glasgow are under the gun. I am afraid that there could be serious injuries or even fatalities from this one. If headed north on I-81, motorists wouldn’t even know that the tornado is overtaking them from the SSW and SW. Fairfield up in the NE corner of Rockbridge may get it, also. Brent and Robin have stated that this “Doppler-indicated” tornado “came out of nowhere, and is holding together fairly well.” Those quotes may be off slightly, but not much.
Meanwhile I have seen no rain today even now, even though it is now after 5 PM, but it looks like that will change within minutes.
How about 1 minute?? Heavens just opened here.
Pulaski reported a gust to 31 last hour as last line went through..
winds wsw at 18 gust to 31…with of course heavy rain…
So yea…looking west …straight in the eyes!
I am “nowcasting.” “7″ is staying with continuous coverage of the radar and satellite views of the Lex./Buena Vista areas. Worst area this minute is just east of I-81 and just east and over the I-64/I-81 interchange. Bright, bright reds on WDBJ7′s radar.
I just looked at NEXRAD radar with a 50-mile radius of ROA, especially to the west, and definitely the biggest radar returns are on the north (NW) side of I-81, but now 7 is showing big rain and winds entering the western side of Roanoke city, too.
My downpour was extremely short-lived. Over now. Good … I can take the old dog out now.
As quickly as it came, it went. Big, staked tents and plastic fence barriers had been set up for the New River Wine Festival near the Inn at Virginia Tech for Saturday. The tents were blown down and one of the nylon ropes was snapped in half! Barriers were strewn all over. For the rest of today, we pulled all the poles out and tent tops are now on the ground. A few tears. Barriers were pulled out of the road and laid flat on the ground…just in case but looks like the tornado watch for Montgomery County has now been lifted. At least we will have a beautiful cooler day for the Festival. Come on over – it’s from noon until 5, features all Virginia Wineries. $25 per person and proceeds go toward scholarships for New River Valley area students.
HokieTrax, I live in Christiansburg, and I can tell you it was the fastest moving storm system I have seen in a long time. I was literally able to see the squall line coming before the wind kicked up like an angry mule, and sent rain horizontally.
Some decent rain, looking like a bit better than .75 of an inch and a couple claps of thunder here in eastern Franklin County. It’s been a decent event so far. Knock on wood!
Trevar, are you a writer? That was a tremendous simile you just made. “the wind kicked up like an angry mule …” Or had you already heard that saying before? I had not, so in any event, thanks. If we were in Africa we could say it kicked up like an angry zebra.
Nary a mudpuddle here on da Knob. Drops bigger than quarters when it started, but if you blinked your eyes you would have missed it.
Tornado “came out of nowhere” doesnt
sound that enlightened. I mean especially
since there have been warnings most of the day.
Yes there is clear air lightning discharge..
But coming out of nowhere seems at least a little silly.
Sounds like tv talk.
The storms moved through Washington County between 2 and 3. Straight line winds and heavy rain. Saw several branches and limbs down on the way home and to my surprise and pleasure, there was .80 in the gauge. We were needing it since we have very little earlier in the week. Now its cool and windy. Wonder which ‘winter’ this is. Dogwood, blackberry and 10th of May cold spells have passed.
What a day in the sky. Some of the baddest storms I’ve ever been around and thru and then I come home to this:
https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash3/556078_376504405730063_100001115192643_980660_409326344_n.jpg
This photo taken by a neighbor who was behind me on I-64 when the Goochland tornado struck 6:30ish. No damage to the home place but was a close call by about 3/4 of a mile. Some tree damage in neighborhood to my west
Looks like I picked the wrong day to quit sniffing glue
Just lots of wind up here on the ridge. Not enough rain to settle the dust.
Joe, I am guessing now, but I think it may have been a particular cell that was a pop-up t-storm at first and then blossomed into a Doppler-indicated tornado very quickly. It may be a question of semantics between you and RR. Anyway, I have not heard yet whether the NWS has confirmed that any tornado did strike in Rockbridge County.
Kevin, I wish you had been here a few minutes ago. In fact, same goes for everyone interested in beautiful sights and dry, clean air. The dew point feels like it has dropped 25 degrees since late afternoon, and there was a vivid partial rainbow (even a hint of a double rainbow briefly) to our east. Air felt invigorating for the first time in quite a while, like several days. I wonder if this means the cold front has gone through … probably.
Kevin….
looked like a good chase today,,
TVS signatures Southeast of Borger and Amarillo.
Tops above 55000ft.
The one that went more due south of Amarillo
didnt look like it ever produced TVS.
The one that slid off toward Childress im hoping
was the productive one for you guys.
Watching in silence from home tonight.
OK chase day today in Texas Panhandle. Saw some supercell structures, Road network didn’t allow us to get where we wanted to on the storms.
Joe, we actually got on a supercell near Dalhart that dived south west of Amarillo. I think we’ll probably be close to Childress tomorrow. Maybe a bit more higher-end kinda stuff tomorrow.
Saw the footage from Hampton. Also seeing the reports of wind damage around the region. Pretty much lived up to form today. Sorry folks didn’t get the rain they wanted.
Don-t know how many people felt cheated by lack of rain..
The 24 hour chart looks like nearly everyone got at least nearly an inch.
One dryer area was in the Highlands west of the Shenendoah Valley
Bath/Highland and adjacent WVa Counties..they appeared to get around 3/4 inch or so. Roanoke River watershed is faring well I would think.
Smith Mountain is nearly full pond and rising.
Would imagine it’ll fill to full pond in the next couple or 3 days.
If im gauging the fill rate right (big if) its about one inch in 30 hours.