Update on tornado records; beautiful weekend to precede possible big rain next week
Regarding the tornado outbreak: NOAA is currently estimating 211 tornadoes on Wednesday and early Thursday, which if it stands, would make it far and away the greatest number of tornadoes in a single outbreak in U.S. history, eclipsing the 148 of the April 4, 1974, Super Outbreak (which included an F2 that injured 6 people in Roanoke/Salem/northern Roanoke County). That number will very likely shift as storm surveys (a) consolidate multiple reports into single tornado paths, reducing the total and (b) new tornado touchdowns or tracks are discovered, increasing the total. NOAA says that the 329 deaths makes it the third deadliest tornado outbreak in its records, and utilizing historical records as far back as 1680, the sixth deadliest in U.S. and colonial history. (Inset map at left depicts tornado reports for all of April, also possibly a record at more than 600.)
You can click here to read NOAA’s ongoing report on the tornado outbreak
Hidden behind the extremely deadly tornadoes is another epic weather story: Flooding in the central U.S. The Mississippi River is projected to hit crests at some locations that it has never hit before since the 1930s, as many feeder rivers are out of their banks and flooding farms, homes and highways. And this is the last thing the central U.S. 
wants to see: More heavy rain on the way over the next 5 days (HPC rainfall project map linked).
Our part of the next round of rain is likely to come Monday through Wednesday, as the map linked here shows. It appears to be a much different kind of rain than we’ve seen recently, with a low forming southwest of us and tracking along a front that has moved south of us and re-introduced slightly cooler air to the region. The bulk of next week’s rain will likely be an overrunning setup (Gulf moisture moving on top of a cooler air mass near the surface), and it could be quite chilly by Tuesday night with lows in the 40s … and perhaps even colder, cold enough for some snow, along the highest ridgelines — not terribly unusual at 3,500-feet-plus in early May. Severe storms are not likely at all in this kind of setup — perhaps some storminess Monday with the initial cold frontal passage, but there is nothing at this time to suggest any kind of major severe weather outbreak in our region. We are starting to see the beginning of a major pattern change that is likely to bring cooler than normal temperatures several days during the next couple of weeks — and calmer atmospheric dynamics than those that have produced recent violent storms.
But meanwhile, the weekend will be sunny and dry with highs in the 70s, perhaps an 80 or two on Sunday. Mornings will have some chill this weekend — folks in deeper valleys especially west of I-81 may be scraping a little frost Saturday morning.
April 29, 2011 - 11:05 PM
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TWC and the NWS were both right. Williston ND (NW corner of No. Dakota) less than an hour ago. Temp 33, wind north at 43(!!!), heavy snow, visibility 1/8th mile. Sure sounds like blizzard conditions to me. Happy middle of spring, northwest North Dakotans!! Meanwhile, I checked on some temps in the Pulaski-Wytheville area a few minutes ago, and nothing below 36 degrees …. except for “King’s Weather Station” in Wytheville, 32.6 degrees!!! One location in Chr-burg and another in Riner/Pilot were at 36. And that is one awesome map of tornado sightings in the eastern half of the USA yuo have posted above, KM!! Nice work!!! AS usual. I hope that the rest of you get to enjoy your Saturday … I am off to deliver mail.
A weather station near Wytheville had 32.9 this morning. Had 36 at my Wytheville home. I saw some frost here and there on my way to work early today.
Snow! I remember when I was in 7th grade it snowed a few inches in Giles and it was early to mid May. I believe it was either 1988 or 89! I think Hugo came through the next fall!
Have seen it snow as late as May 9th down here in the gap. Would be cool to see it happen again this late.
did someone mention the ‘S’ word……..Pleased to meet you Hope you guess my name
Kevin, I remember a fella from around Paint Bank telling me years ago that they had a frost in June. He called it the year of no summer. I can remember going to Potts Creek for the second opening day in early May and it blowed snow and ice froze in the rod guides. Must have been 35 years ago. You have any info on that?
Jared, Zach, Frosty, and wd …. there may be frost and high elevation snow during the first ten days of May this year. I base that on what Kevin has indicated about the AO and NAO alphabet soup and on the CPC forecasts. And wd, 35 years ago would make it 1976. If I had to guess a year, I would go with 1977, because that was the winter that was so incredibly, brutally cold. Ohio was so cold in January that it (and I am fairly sure that “it” was the entire state) was declared a disaster area, and Buffalo got so much snow (even by their incredibly high standards!!) in late January and February that the Buffalo Sabres NHL team had to play all their February games on the road. City and airport were both crippled.
Kevin, I have been thinking about the upcoming cool/cold spell for the first two weeks (after 5-3-11) or so of May. I can understand and agree that this will greatly reduce the chances of the catastrophic t-word for SW and Central Virginia (and neighboring WV). But what about after that? With that relatively cold air in place, could an invading warm air mass (especially if it was really warm, even hot) trigger still more trouble?
Doug: There could still be some thunderstorms even during the relatively cool period ahead, as there will be some up and down of temperatures and a few fronts pushing through. But usually our worst threat of severe weather occurs when a cold front from the west pushes into warm, humid air ahead of it. One thing the northwest flow does is slow down or eliminate the flow of Gulf of Mexico air northward. That will cut down on the basic fuel of storms. Another thing that happens is the storm track changes so that lows are not continually moving NE to our NW, like they have been, sucking in stiff SE winds that ramp up the rotation in the storms.
Turning our upper air flow out of the NW can in the right conditions bring storm clusters or lines southeastward from the Ohio Valley — more likely in midsummer when heat and humidity are more widely established than in May.
The HPC just took our rain for next week and moved it west. Bummer, we pretty much got skipped this week in Wytheville.
http://www.hpc.ncep.noaa.gov/qpf/p120i00.gif
That would be a big bummer for the Mississippi/Ohio valley too if that verifies — even more rain in a drainage basin that’s maxed out and flooding already.
Rick, one of these years your home area will get bombed with rain, and sometimes folks have to be careful what they wish for in that regard. Nothing at all personal intended there. Just that probably all of us who have been around a long time and who have paid attention to weather know that sometimes when an area has been dry for a period of two or even more years, once the rains come they bring so much so quickly that there is flooding. And the opposite can happen, too. Take the winter and spring of 1998 around here. Roanoke got 30 inches of rain from January through May, about a 12- or 13-inch surplus for those 5 months. RRA got 11 inches for the rest of the year, about a 13-inch deficit for those 7 months, and a roughly 4-year drought cycle had started!! Didn’t really end until the El Nino of 2002-2003 got going in the autumn of 2002.
Anyway, Rick, I didn’t finish my thought. Something really strange has been going on since at least late 2009 with your part of Wythe County. Rain has been diverted away time and time again. I did look up many rainfall totals on afws.net Thursday evening, and since they showed the 24-hour totals, they gave a pretty accurate picture of what happened. What really struck me was that within the same county there were big differences. Most of your county’s 5 locations came in with light amounts, especially the “2-way Wytheville” site right in W-ville (about a 1/4 inch, as I remember it), but at least one of the two sites in the NW part of the county near the Bland border got quite a bit more, maybe more than an inch. But in the county just east of you, Pulaski, the situation was really weird, almost the opposite of Wythe. Usually the two sites in the hillier locations well north of I-81 get more rain, but not this time. The “Peak Creek” site right in Pulaski and one other, perhaps the Caseknife location right on the Pulaski-Wythe border just north of I-81, got way over an inch, maybe 1.5+, while the NW sites got amounts less than 1 inch. It was the track of the storms that mattered.
Last stuff on years-long trends in rainfall. It reminds me of how frustrated Nancy and I were when we first moved in here in January 1999. Our builder did not plant grass seed the previous autumn (couldn’t — the house was being built and all kinds of vehicles going through the property), which I was hoping could happen. So the seed did not get in the ground until 1999 spring, which is nearly always a less preferable time to plant (at least that is what I have been told numerous times). Sure enough, we got dry weather. What was really frustrating was June 1999. Numerous t-storms would rack southern Botetourt County that month, and one night we had an absolutely stupendous light show from a long-lasting storm that Robin Reed claimed had 1100 lightning strikes!! They got 1-2 and even more inches of rain from that one storm, and a ton of rain that month, and we got just about zippo. Finally we got some t-storms to get us starting in July, and the lawn was under stress for about 3 years from the rainfall deficit, although the Labor Day hurricane of 1999 sure helped, but that was a one-and-done scenario. Then came late 2002 and we were in clover. Sooner or later the trend will swing your way, and you will start to get more rain than the rest of us. That is usually the way that it works. By the way, Rick, did you get more snow this past winter than Roanoke’s 11 inches? Snowfall is one of the very best ways to solve a drought situation, because it nearly always seeps into the ground slowly, over many weeks.
I know it’s several days out, but does Wednesday look particularly rainy? I have outdoor plans that day and I’d hate for them to be ruined.
Doug: I live real close to 2-way Radio, Wytheville. Bring on the heavy rain. I have a new roof, new gutters, a property that drains well and a garden and new trees that need the rain.
Jennifer: Wednesday looks to have a chance of showers early, clearing out sometime during the day. It’s Tuesday-Tuesday night that look rainiest right now.
Kevin beat me to it, Jennifer. I watched WDBJ7 at 6:15 PM (Jay Webb, I think) and he indicated almost exactly the same as what KM just commented. I think Jay said there was a slight chance of a shower Monday evening, bigger chance of showers on Tuesday and Tues. evening, and Jay definitely said a 30% chance of an early morning shower on Wednesday. The WDBJ7 weekly planner shows that, too: http://www.wdbj7.com/weather/7-day-planner/ . If you click on that link, assuming I set it up correctly, you will see that Chan 7 is forecasting a Wed. high of only 64*, almost 10 degrees below the normal of 73 for May 4th. Which is our anniversary. I better go get a card ….
Doug, I disagree that snowfall here in SW Virginia is much of a moisture factor. We average about 30 inches a year, so that is only about 3.0 moisture of a typical average of 35-ish inches. It does tend to soak in well rather than run off, but not always (flood of March 2010). Snowfall is just not a significant moisture factor in SW Virginia. In a normal winter (such a thing is hard to find lately) rains are way more important in the December-February time frame than snow.