UPDATE 9 AM, 5/13: Flash flood watch issued tonight-Tuesday as gorgeous weather period turns soggy
UPDATE 9AM, 5/13: As expected, a flash flood watch has been issued for part of our region, generally from Roanoke southwestward along Interstate 81 and southward along the Blue Ridge into northwestern North Carolina. It is effective from 9 p.m. tonight to 9 p.m. Tuesday night. So far we’ve started Mother’s Day with a little bit of sunshine in the Roanoke Valley and nearby areas. Moisture will gradually build today with showers encroaching from the south and west later in the day into this evening. END UPDATE
UPDATE 1 AM, 5/13: Saturday night’s rainfall projection fls through Tuesday evening from the Hydrometeorological Prediction Center show rainfall may top 3 inches in some locations from the slow-moving upper-level low that will begin spreading showers into Southwest Virginia during the day Sunday, with heavy rain possible overnight Sunday into Monday. Don’t be surprised to see the National Weather Service in Blacksburg issue flood watches during the day Sunday for some or all of our region. You can follow the advance of rainfall and its potential for the region on the Radar /Future Cast link at right. (Just ran the Future Cast for rain accumulation, and it concurs with HPC, with about 3 inches of rain for Roanoke by 1 a.m. Tuesday). END UPDATE
It would have been hard to create a prettier day for Virginia Tech’s commencement Friday than the one that occurred (well, OK, I know some folks would have liked it warmer, especially after a morning low of 36 in Blacksburg and kind of a nip in the breeze even as it pushed into the 60s). Saturday will be similar, though a bit warmer, over most of Southwest Virginia (far southwest areas west of I-77 may get a few showers). But Mother’s Day — and especially the day after — are likely to be a different story. A slow-moving upper-low bringing rain and storms to Texas is going to dawdle east and northeast over the next few days. That will supply a lot of Gulf of Mexico moisture, squeezed out by upper-level impulses and our region’s higher terrain. The result will a period of significant to downright heavy rain, possibly exceeding 2 inches in many places by Tuesday. Mother’s Day is a bit of a question mark — the best chance of showers will be west of Interstate 81, as moisture slowly builds ahead of the storm system. By sometime in the afternoon or evening, rain will become widespread, and periods of rain are expected to continue into Monday and at least some of Tuesday.
Having a slow-moving Southeast U.S. upper-level low deliver a period of significant rain has become a tradition connected to the departure of the Virginia Tech storm chase team for the Plains states. We’ve seen this happen with amazing regularity the day we leave or a few days thereafter, and the circulation patterns leading to rain here often dry out the central U.S. for a few days. We’re planning to leave Tuesday, likely headed for the Northern Plains as moisture and jet energy slowly recharge in that region by next weekend.
May 12, 2012 - 12:31 AM
RSS feed 
48* here with a pretty Last Quarter moon above at “Oh-Dog-20″ hours. Some widely scattered, thin clouds around. Mostly sunny.
OH …. I mentioned it late last night, but it needs to get mentioned on this thread. The NALC (i.e., we letter carriers) will be conducting a food drive today, at least in Roanoke-Salem-Roanoke County-Vinton. If you wish to participate, please place a few canned goods in a plastic or paper bag and set it by your mailbox early today, before your letter carrier arrives. Food goes to help feed the hungry. In advance, thanks!!
Kevin, May all of you (storm chasers) have a safe and productful trip to the midwest.
39 F this morning up here on the ridge – partly cloudy and no breeze.
Only got down to 36 here last night and no frost. yea for my plants! May this be the last time we have to worry about that!! Kevin,have a safe and productive trip(s) and may you see all the weather you want!!
Right now I would say we are not going to have any major severe outbreaks while we’re out on the first trip (return to Blacksburg by Thursday, May 24). But then, we’re not really looking for outbreaks, just a few good storms. As always, simple highway travel is the most dangerous thing we engage in.
Doug – I was thinking of you as I put out a bag of canned goods for my mail carrier to pick up and thinking what a nice project this is for the USPS to take on annually – I appreciate the extra effort on the part of the mail carriers for a good cause.
Driving up to Mt. Lake soon for a hike with a friend today to enjoy the last bit of good weather for a few days. It is getting more overcast here in Hokieburg. After this past week with all the commencement preparations, I am actually ready to be socked in with some rain for a few days. I can finally get my house clean from a semester of clutter.
My folks in Houston were under tornado warnings last night from the system that is headed our way but thankfully wasn’t too bad. Kevin – have a successful but safe storm chase trip!
Kevin, in case I don’t get to it before yall leave, have a goodun and a safeun. Keep us posted on what yall isa sendin back home now.
Great, great weather today.
REST OF THIS COMMENT IS ABOUT THE FOOD DRIVE: Please skip it if not interested.
I am exhausted. Luckily my wife Nancy came out and helped me collect the food at mailboxes for quite a while. After lunch I was on my own. Had about 300 deliveries (i.e., addresses) for that after-lunch timeframe, and collected 27 hods (the white postal baskets) of food just on that section. Total was about 50 hods for the entire route. When I got back to the post office about 5 PM, the dozen or so volunteers gaped in awe when I opened the back door …. it was full of food. One more guy arrived after I did, and he probably had about the same as me, too. In past years the Roanoke district has collected over 100,000 pounds of food for this drive …. got a feeling that with the good weather, we might set a record this year.
If you were busy or forgot about the postal food drive today, but want to donate, it is not too late. Just put some food next to your mailbox on Monday or Tuesday.
I will wish the Weather Wizard and all of his storm chasers good luck later. For now, HAPPY MOTHER’S DAY tomorrow, ladies!! May the weather cooperate with your plans.
How much is it going to rain? Here is an actual report of the quantitative accuracy of three models over various time spans. An easy to read graph.
http://www.hpc.ncep.noaa.gov/images/hpcvrf/HPC6ts25.gif
NWS is quite optimistic with its completely dry forecast for the Wednesday through Saturday period this week. I guess they want to give us some hope after we get through the next three days of soaking rains, but I really think thunderstorms will be in the offing for mid to late week each and every day.
HAPPY MOTHER’S DAY to all the moms out there. I’ll be spending time with 3 moms (my wife, mother and mother-in-law) today so won’t be on the blog for a while.
Plan to post something new this evening to carry us overnight into Monday.
Kevin, do you all drill for what you do in case the tornado alters course and gets too close to your storm chaser van? Also, with all the storm chasers that are out there this time of year, is it common or rare to have some of the equipment/personnel damaged/injured each year?
With the increasing popularity of using unmanned drones for things from blowing up terrorists to maintaining utility right of ways, has NOAA experimented with flying “weather drones” into twisters so they can get data from inside the tornado while the operator is at a safe distance? (What’s the fun in that though
) Granted the drone would likely not survive, but I’d guess the instrumentation might.
Good luck in your search and stay safe out there.
Kevin: Happy travels and be safe! I hope you have a wonderful and weatherful time.
Hey, Kevin, first of all congrats to your 3 mothers! Be grateful for having 3 mothers involved in your life.
Secondly, because you conduct two major weather prediction contests here on the blog, how about predicting the number of tornados you will see with your own eyes on this trip? And the number of funnel clouds, even if some never actually touch down.
Or if that does not appeal to you, how about at least a sentence or three about your general outlook for the trip, given the current situation? I realize that the outlook can look fabulous, but you get “unlucky,” or the outlook can look unpromising, but you catch a few big ones.
I would also like to hear from you whether you think the cold late winter of 2011 (especially in the Northern Plains) made conditions ripe for a big spring tornado season, and whether this mild late winter of 2012 has had any effect on overall tornado activity nationwide so far in 2012.
BULLETIN: THE FOLLOWING IS A WEATHER-RELATED COMMENT. Since things are sorta slow here today, I thought I would undertake another research project. I added up the 2012 rainfall totals for the Blacksburg/Bluefield (WV)/Danville/Lynchburg/Roanoke pentagon cities, and compared them to their year-to-date averages. The following are the situations through April 30.
1. First, the normal rainfall totals alphabetically by city. The 4-month norms are incredibly uniform, with one exception …. Danville. And it is the opposite of what I would have expected, at least for the JAN-APR timeframe. Danville usually gets about an inch MORE of rainfall than the other 4 cities. Blacksburg’s 4-month normal: 13.01 inches. Bluefield, WV: 12.50. Danville: 14.00. Lynchburg: 12.96. Roanoke: 12.64.
If you have been reading this blog regularly, you can probably guess which city of these five has been the wettest and which has been in 2nd place.
2. The actual totals by city through April.
Blacksburg: 14.26, up 1.25. Feb was wet by about 0.70 and April was wet by more than 1.3 inches, overcoming a dry (-0.99) January.
Bluefield: Really wet. 17.44 sopping inches, up 4.94 inches. February was wet by almost 2.4 inches, March by about an inch, and April by about 1.8 inches.
Danville; Very dry, compared to their biggest normal. Only 10.42 inches (almost identical to Roanoke’s …. see below), down a huge 3.58 inches compared to their normal. All 4 months were drier than normal. JAN was dry by 1.43, Feb. by about 0.90, in March Dville got 3.55 inches, but that was still less than normal by more than a half-inch, and April was dry by exactly 0.70.
inches.
Lynchburg: Almost exactly normal … how has that happened? Actual has been 13.05 inches, just 0.09 more than normal. JAN was dry by 0.92 and FEB by 0.32, but MAR was a soaker, a +2.2 inches. LBurg’s 5.78 inches in MAR was the wettest total of the 20 measurements. But Lburg was dry again in APR, by almost another 0.9 inches.
Roanoke: Both JAN and FEB were drier than normal here, which is almost becoming an automatic over the past 12 years. JAN by a big 1.23 inches (ROA’s 1.69 inches was the LOWEST single monthly number of the 20 measurements), and FEB by an additional 0.68 inches. MAR was normal, but APR was dry also, by 0.33. The 4-month total for Roanoke was 10.46, but that was only down 2.18 inches compared to normal and less than Danville’s 3.58 deficit.
John: An ounce of prevention is worth a pound of cure in the situation you describe. We always plot escape routes at any stop we make and have the vans pointed in a direction toward an escape route when we stop. Motors stay running … never want an alternator or starter issue to leave us stranded. Injuries seem to be very rare among storm chasers in general, and a few busted windshields is usually the extent of damages among the groups that get closer to storm hail cores (we try to skirt those). In all the years that VT instructor Dave Carroll has been running storm chases, the only injury requiring hospital attention was related to broken fingers from catching a football while waiting on a storm. A bigger concern for us is those situations where there is highly publicized high risk of tornadoes and extreme chaser traffic following 1 storm — we’ve been in the middle of that a couple of times, and once bailed out of a chase for simply safety reasons. Most of what we do is in open terrain on more isolated storms, so traffic usually isn’t a problem. I don’t know if the weather service has employed drones, but I know Reed Timmer of Discovery Channel “Storm Chasers” fame has had radio-controlled aircraft flying near tornadoes before.
Doug: We do not expect a major tornado outbreak while we are out on the first trip (leaves Tuesday, returns by Thursday May 24). We are watching disturbances moving over the Rockies, that may interact with moisture banking on the eastern upslopes (kinda like happens here, except stickier air, bigger mountains) and, by next weekend, a significant jet stream trough and cold front that have a better chance of firing more widespread severe storms. Ascertaining the strength and placement of that has been difficult this far out. I would expect to see no more than 1 or 2 tornadoes, if that, on this first trip — but as always, if you get on the right storm at the right time, even in an overall not-so-conducive pattern, it can exceed expectations quickly.