Vigorous storm system likely to bring some heavy rain late Monday into Tuesday
FLOOD WATCH ISSUED FOR TONIGHT AND TUESDAY ROANOKE AND WESTWARD
Increasing moisture was very evident Sunday in the form of an overcast sky of low clouds that kept daytime temperatures cooler than they’ve been in months. Roanoke’s high of 66 was the coolest since May 14, and Blacksburg’s 65 the coolest since June 2, each 10-12 degrees below normal. Lows of 61 and 56 were each 3-5 degrees above normal, also owing to the gathering humidity, but that left the day as a whole still 2-4 degrees below normal. Excluding only Saturday, each day since Sept. 8 has averaged at least a degree below normal in temperature, and it appears likely the majority of days from here to the end of the month will also.
Over the next 2 days, Southwest Virginia will experience its first cool-season type storm system of the fall, with influences from disturbances in both the southern and northern branches of the jet stream. Sunday evening’s infrared satellite photograph, inset at left, captures the upper-level low in Texas very well, pulling a plume of Gulf of Mexico moisture into eastern Texas, Oklahoma and Arkansas, streaming eastward throughout the Southeast and even into southern Virginia. This is a big piece of what is to come, as it will lift buckets of moisture from the Gulf northward over the next 48 hours or so, leading to widespread and locally heavy rainfall over many southern states. The wider view of the same satellite picture, linked here, also captures the second piece of the storm system over the Dakotas. These two systems will join forces near or just north of us by Tuesday to create a strong early season low that will move inland through the East. It appears the heaviest 
rain in Southwest Virginia is likely to occur late Monday night and during the day Tuesday, with widespread amounts near 2 inches and some higher amounts expected in western Virginia. Strong winds aloft, changing direction and speed with height, also carry some threat of severe storms with damaging winds developing Tuesday, though it appears the greatest threat will be east of the Blue Ridge where warmth and therefore atmospheric instability are likely to be greater. I would not be surprised if there end up being a handful of tornado reports in central and eastern Virginia come Tuesday afternoon.
Late Tuesday or early Wednesday, a cold front will push the rain out, and bring a day of breezy cool behind it in which temperatures probably will not make the 70s most places in Southwest Virginia. Thursday morning looks to be chilly, lots of 40s, maybe a few of the typically coldest spots reaching the mid-upper 30s. Another push of cold, likely stronger than this week’s, arrives around Sunday or Monday. The long-term pattern favors continued reinforcements of cooler-than-normal Canadian air through most of the next couple of weeks.
September 16, 2012 - 11:30 PM
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Doug – went outside to walk the dogs last night and our Mr. Toad was right there on the porch – I thought of you. We are looking forward to some welcomed rain up here on the ridge. We have had a total of “0.09″ inches of rain in the last 24 hrs. The fog/clouds are really socked in this morning – visibility is very low.
Who is in charge of NOAA??? (Maybe the real question is do they know what they are doing.) I see comments like “Flood Warning” or “Flood Watch” routinely posted and we don’t have a drop of moisture which follows AND if there is a small spot which gets rain and even if it is heavy rain, NO flood results…not even localized flooding. During a recent period we had this “warning” posted and over the several days MAY have had a total of 1 inch. I also notice red banners which say “Hazardous Weather Statement” on the web site. When you click it you more often than not see a following comment, “No hazardous weather is expected at this time”. WHAT???
I think maybe these people are posting in fear that if they get it wrong, someone will file a suit agains them. Thus, better to error on the side of bad weather.
Bubba:
Does someone still get a monthly bank statement if he has no money in his account? The Hazardous Weather Outlook is issued regularly whether or not there is hazardous weather. Its primary purpose is to tell local officials and weather spotters of any possible threats in upcoming days. And it’s just as important to let them know there are no threats, so as not to unnecessarily divert resources, as it is to let them know there are threats.
As for the broader criticism of NOAA — there are wrong forecasts, and there is a tendency to warn toward the higher end of what is possible in a situation, mainly because people tend to ignore warnings even when there is a huge threat. But the margins of error of forecasting, the lead time on severe weather warnings, the degrees off on temperature forecasting, the number of days out forecasts can be fairly accurate, etc., are all improving.
Here is a an article that looks at modern weather forecasting, noting its flaws, but also its vast improvements in recent decades:
http://www.nytimes.com/2012/09/09/magazine/the-weatherman-is-not-a-moron.html?pagewanted=all
Found this on woolly worms:
http://www.almanac.com/content/predicting-winter-weather-woolly-bear-caterpillars
Saw a side link on predicting weather with a pig spleen! Really?
Adding a thought on flood forecasting: It may be the most difficult type of warning issued, because not only does the amount of rain falling in a given time have to be ascertained, but also how much runoff there will be, which is based on a huge number of factors (urban vs. rural, how dry the soil is, more when leaves are off trees, etc.) and also the specific geography of drainage basins. A tornado or severe thunderstorm warning is issued based on radar detection or human observation regardless of any other factor. Winter storm warnings are issued with regard to how much snow or ice is expected to fall. Those warnings are issued based solely on meteorology, whereas flood forecasting is a nexus of meteorology and geology.
Good Morning fellow bloggers. We had a couple of tenths of rain yesterday morning and now we are preparing for the bigs rains tonight and tomorrow. I got my post surgery walk in this morning for fear the rains may keep me inside tonight. Doug, I will come and walk your route as soons as the old heart is healed. Rest assured I will be keeping those walks and diet up to date since I do not want my chest tore apart again. Hope you all have a good day and mine are definitely good with the new blessings of Life God has given me.
While on the note of flash flooding, here is the current guidance used to determine if a flash food warning may is necessary.
http://www.srh.noaa.gov/rfcshare/ffg.php?duration=3&location=VA
It’s SNOWING!!!! Ok, Ok, not here…BUT at 11,000ft in Denver LOL. I am looking forward to the rain today. My allergies have gone haywire.
While traveling down to the “country home” over the weekend, we went by rt 623 and it made me laugh. It starts out paved, for probably less than 100yds and becomes a pig path gravel road. Then I saw that Hokie Trax went that way into the garden. I told my hubby we would have to make a trip that way sometime soon.
Michael Hoback, so glad to hear that you are on the mend. My very first job out of nursing school was working with heart patients. I absolutely love cardiac and feel that one day I will go back to it once my kiddos are grown and out of the house. Take care of yourself and make sure to use your incentive spirometer
Interesting that our “Miller A” LOW is being watched by the NHC for a very low percentage chance of sub-tropical development. Keep talking tropcial anything…………I want rain for dry land!
http://www.nhc.noaa.gov/
Curious discussion on that link from NHC, Rick. They identify it as nontropical and then give it a “near 0″ percent chance of developing into a subtropical storm, but still circle it.
Shanon: I lived in Denver for a a short time in the mid 80′s. We had 4 inches of snow on September 13th one year. I loved it!
Our soon to be rainmaker is really pulling the moisture out of the Gulf.
http://i47.tinypic.com/34xnkg2.gif
Wonder if this storm is the catalyst to get the El Nino going. Doubtful though, pattern after this week is cooler than normal but no real pattern changer as far as El Nothingo is concerned. Back later….off to the wild blue yonder…
Henry M. is suggesting that this storm is going to show the weather pattern for the winter to come! Is he going to far out on a limb with this? He said all indications show this winter is going to be a doozy for the eastern part of the country! Sure hope he is correct!
Anyone else see that airmass coming this weekend? Brrr.
I see the NWS has shifted the 2 inch line one county to the west on their storm total map.
At this point, there’s at least a +/- .50 margin on any rain forecast map, so I’m not sure being in a 1.75 zone instead of 2-inch zone is much different.
Quagmire, this does look a lot like the type of storm system we get during an El Nino fall/winter, we’ll see if it repeats.
Jared, there is some truth to fall storms often being harbingers of winter patterns, but of course it’s not etched in stone. There is no way you can say a single storm happening in September will be repeated by similar storms in winter. There may be some truth that the weather pattern now is showing its hand for what it play some during the winter.
Started raining here about 1:30 pm this afternoon. It has been a nice steady rain so far – have “0.22″ inches in the rain gauge already. Lovin’ it!
Interesting article on the wooly worm, Hokie Trax. I saw another wooly worm today in the yard – all light brown. I remember seeing them in the fall of ’09 and they were all black – and we all know what happened a couple months later.
Jared, Henry M. was the primary blog I followed until a few years ago when I stumbled across Kevins blog. There are two things you can count on with his forecast. If he is right, no one will remember it. If he is wrong, he will be treated as though he single handedly caused all the evil in the world. He likes to go out on a limb and say what he thinks, which is what a forecaster should do, but he can hype things a little at times. This past winter I don’t think forecasting went to well for many, including Henry M. but in past years I have seen him make calls on storms a week or so out that no one else would, and turn out to be right.
What I have always appreciated with Kevin is he tells us what he thinks will happen, and then gives the other potential scenarios. Also, Kevin can consider more local geography and history of this area to better refine what might happen.
The main low center is likely to track a little west of us with this storm. Snow lovers (and snow haters, who hate ice too) aren’t going to want that track to repeat much this winter — typically a mix to rain type event on that track, starting as snow if cold air is deep enough.
This is going to be an ideal general rain for many, early enough in the fall that it won’t knock a lot of leaves off, and combined with the cold fronts to come, may get fall foliage going a little early this year. Some local areas could get some street and small creek flooding where heavier downpours align repeatedly.
To his credit, I think Henry Margusity was on board with this big rain last week when I was doubting it still. It’s gonna happen, 1-3 inches, locally more, very obvious on radar now how it’s developing. Just wondering how much you can project 1 storm 3 months out into a winter pattern. 2009-10 did drop some hints (Nor’Ida nor’easter just a month before Dec. 18-19) before it slammed us. We’ll see how it develops.
GO NORTH!!!!! I know I know the rain is good, but lets hope this holds up and we see more of this between late November – Early March…
Got 0.40 so far in Wytheville.
Personally, I could use another 2011/2012 winter. But I’ve made arrangements for a worse one. If it’s a rip snorter, then Hee-Haw said it best.
Only looks like 0.10″ here so far. Been a lite, gentle rain since maybe 2/3 PM. Hope it stays civil.
GREAT, GREAT TIMING of this rain. I was delivering in dry conditions all day until about 2:50 or so, then had some light rain. It was steady stuff driving home. Checked the gauge at 4:20 PM and we had a total (including the 1/10th from yesterday) of 1/4 inch. Just checked it ten minutes ago and now we are up to 4/10ths and climbing. OK, OK, I am on board, I now believe we are gonna get more than an inch, even Leo Lady, also.
Music link: http://www.youtube.com/watch?v=FeRx-1VV6QA Enjoy the music from the 60s …. Key phrase is at about 0:31 seconds of the video.
I would love to do some research on whether a cold autumn leads to a cold, snowy winter (or even a cold, snowy first half of winter) for SW Virginia, but I only have detailed records going back to 1-1-2000. And I bet there was not even one year during these 12 previous (’00 through ’11) autumns when the October-November timeframe as a whole was even 3 degrees colder than normal. I DO remember that November 2009 was very warm (sorry, this is a repeat comment from a couple of days ago) and had me believing that all the talk of a big winter that time was exaggeration. I still think that you snow lovers ought to be rooting for a warm November, not a cold autumn, but that is based on a sample of one (year).
Oh, and remember what happened about a year ago? Parts of the Northeast were slammed with that (in places) huge snowstorm just before Halloween, and many (not here on this blog) folks up there cried out, WOW, we got bombed this early, we are gonna have a monster winter. WRONG!!!!
Current radar trends are not your friend if you want signigicant rains. The main slug of moisture is riding well west of us and north, with NC and east TN getting hardly anything right now. Looks like significant rain will end, at least temporarily, in the next hour across most of the NRV and RNK. At least this is not snow, or alot of folks (including me!) would be jumping off the cliff right now. I think our chances of getting more than 1.5″ max are pretty slim based on the current radar trend.
Doug, Jared,
I remember very vividly the winter of 2002-2003. That winter was a great one. It was a weak Nino, but we had I’d say 5 + moderate events.
ANYWAYS – let me get to the point. My favorite weather to watch is WXII 12 out of Winston Salem. I was watching them (I was 11 haha) and remember the meteorologist saying in early November “Folks this pattern has been established for about a month, and it show no signs of slowing down. Give it about a month and our mountain communities will be shoveling.” (That may not be word for word, but the general just) Anyways, about a month later, (First 10 days of December), we had the first of many snows. I would say with fair certainty that the patterns that set up in late Autumn certainly carry over into the 1st half of winter. Usually after this, the pattern starts or tries to break down. Not always succesful. Last year was a great example of the pattern trying to break down January-February and it not really happening. We did how ever get more cold shots, and a storm in February. 09-10 is a good example of this, too. The pattern took hold in November, December we got hammered. Pattern tried to break down in January, only to re-establish itself in early February and hammer us. After that, March warmed up and the pattern flipped. It is hard to sustain any pattern for more than 3 months as is. It is much easier for the pattern to gradually break down, gradually change, and have more swings/variations in your weather after roughly 8-12 weeks of any pattern.
These are just my thoughts from my observations over the years.
Doppler Carol, toad around the home means no lighter than expected rain (so sayeth Griggsy …). I bet you get at least 1.5 inches from this event, including what you got yesterday (if you got anything then). Those little guys (the toads) are cute, aren’t they? When I see one, I keep our old dog away from them, and not only to let the toad get on with his/her life. I think I heard that when attacked, toads secrete some unpleasant or even possibly harmful fluid, but maybe that’s only certain toads.
Jared, what pattern are you talking about that got set up in November 2009?? It was much warmer than normal that month, at least here in ROA. Even the first 3 days of Dec. continued warm. It was one degree colder than normal on the 4th of Dec., THEN the cold invaded, setting up the huge snowstorm, etc.
Gotta disagree with you, Mike. Radar much more impressive than I was expecting at this time. Looks like 1-3 inches areawide to me.
On the other hand, you and the weather guy in Winston-Salem are/were correct generally about October/November period of 2002. First 13 days of October were warm, then 12 of the final 18 days were cooler than normal. November ended up only 1.1 degrees colder than normal, but that was only because of a very warm spell of 8 days from the 9th-16th. First 8 days and the 2nd half of Nov. ’02 were quite cold.
WHOA, my comments should have been directed to Zach, not Jared. OOPS …. apologies, fellow golfer!!
Kevin, what did Mike say that you are disagreeing with? Or was it a twitter post?
Ah, you meant Blacksburg Mike’s 7:24 comment. Never mind.
Zach, I am glad that you brought up the late months of 2002, and the winter of 2003. What I remember most about that winter was that it ended the roughly 48-50 months of extreme dryness here in Roanoke. The first 5 months of 1998 were incredibly wet here, 30 inches of rain. Then through August 2002 Roanoke was so dry that the shortfall over those 4 years was something like a year’s worth of rain. I remember telling a frustrated postal customer in August that year that our frustrations were about to end, because of the impending El Nino. I said that the drought would be over by the following spring (meaning that the reservoirs would be full. For an incredible change, I was right.
The other thing about that winter was the number of snowstorms Roanoke got. Here in the city, I don’t think any of them dumped more than 5 inches, but we had something like 7 of them. I remember long-time residents commenting to me that they couldn’t remember a previous winter when ROA got so many snows.
Blacksburg Mike, I just took a look at the radar, and I see why you made your comment. From Pulaski County westward all the way to (almost) the Cumberland Gap (Virginia/Tenn/Kentucky tri-border), there is no rain. But I can also see why KM made his comment. Further west in Tennessee “the world is ending.” Lots and lots of heavy rain. True, most of that will hit WV, I guess, but we will probably get plenty, too. If not, you definitely get the “blue star” for your early call.
Kudos to everyone on this forum who add their educated .02. I own a concrete plant and my income is directly affected by the weather, which caused me to become a weather fanatic in the first place! Countless times, I tell contractors what to expect for the day and week, and most of the time, I’m right, or close to it (thanks to you guy’s collective wisdom). They all want to know where I get my info from, and I tell them. In my short time here, I think the posts on any given day have doubled at the least! Thanks to you all.. although it’s going to be slim pickins the rest of the week because 70,000 pound trucks and mud don’t go together very well!
Kevin, not sure if any others here look at soundings, but I find this quite impressive with regards to the directional shear needed for spinups and embedded low-topped supercells.
http://68.226.77.253/skewts/NAM-test/027/SKT_NAM__KFCX.png
CAPE is rather low (~500j/kg) but with the shear, I wouldn’t be surprised seeing some spinups in central VA especially if they become more unstable.
SREF seems to agree with central VA for tornadic activity.
http://www.spc.noaa.gov/exper/sref/gifs/latest/SREF_prob_combined_sigtor__f030.gif
I could see New England having more of a high wind event and the SPC keeping a 30% probability wind threat with maybe a marginal tornado threat up that way because of the strength of the jet. I also wouldn’t be surprised to see a 10% tornado probability issued in the Mid-Atlantic somewhere by the SPC on their day 1 outlook.
That’s all the weather geekness I have to add for now!
I’m looking more at the overall organization of the system on the national/regional radar than specific movement of any particular piece of it. The stuff in Tennessee is translating eastward with the storm and there is ample moisture being pulled up through Alabama and Georgia. In the last hour, some heavy showers have coalesced down in NC, and those are getting pulled northward. I’m confident we’ll get to at least 1.5 inches in 80-100 percent of the region based on radar trends. Would be very surprised if anyone gets less than an inch. Of course, most spots have already put .15-.25 on the board, so it won’t take but one heavy round of rain to get to an inch.
This system bears some resemblance to me to the April 16, 2011, system. If you ran or volunteered at the Blue Ridge Marathon that day, you remember that one well. The low pressure system was much more wound up much earlier on 4/16/11, but the rain area is actually larger ahead of the storm this time. 4/16/11 produced a prolific tornado outbreak in central/eastern NC up into southeast Virginia — may see a somewhat lesser version of that farther north, eastern Va up into Delmarva and maybe NYC/New Jersey area on Tuesday.
Blacksburg Mike, you would be interested that 4/16/11 only produced .87 for Blacksburg but was 1.85 for Roanoke, with locally 3+ and some flash flooding in southern Roanoke County (near me). Not saying we’re going to repeat that, but even though the forecasts favor Blacksburg for a little more than Roanoke, I really think Roanoke will end up getting more rain simply because Roanoke usually gets a little more upslope overruning effect off the Blue Ridge with south/southeast winds ahead of a low tracking as this one is. Rain bands seem to follow the Blue Ridge from NC into Va a lot in these situations.
Ben: Someone from VT tweeted out the sounding from Baltimore earlier, looks textbook for tornadoes. Instability is the limitation. Good thing we’re not going to have a lot of hot sunshine out ahead of this.
Anyone want to bet against Kevin’s prediction that Roanoke will get more rain from this system than Roanoke?? I’ll make the bet …. WITH Kevin, not against him. Also, it used to be that I would get more rain than Roanoke Regional Airport when a system approached from the south in particular, and sometimes from the SW, but that has not always held true this year in particular. I wonder if that will happen this time. No predictions on that from me.
Lots headed toward the valley overnight..
Watch that area from Dothan Ala to Macon Ga..
the vector on that area more favorable to
scoot east of the Blue Ridge..
weather box still out from Macon to Ashville.
Its gonna be quite a soaker..as this one is moving slowly
and will train over some areas.
Put the frogs in the barn.
Radar is starting to fill in in NC now, and if the rain in TN/KY can push east then we will do well. Still concerned at how relatively “empty” the radar is now across the I-81 corridor from RNK to Bristol. Also, the general trajectory of heaviest moisture seems to be running on the west side of the Apps. Maybe I am over analyzing the current trends, and believe me, I hope I am, because we need big rain here.
Sitting at .30 from the first part of the system here in Goodview
Well, here’s how last night’s NAM showed what the radar was supposed to look like about now. You can compare and contrast.
http://blogs.roanoke.com/weatherjournal/files/2012/09/NAMsimradar0917.gif
Granted we need the rain, and I mean really need the rain. However Kevin’s comment about the April 16, 2011 rain scares me a bit. The little creek that runs through Fishburn Park in Roanoke came out of its banks in a matter of hours. The flooding from that creek closed roads in my neighborhood and made it difficult for me to get home that day. I have photos of some of that flooding and it is quite remarkable. I don’t really want to do it quite that way again.
pretty doggone close…its nying a little more NE-SW
than last nights NAM…but they have the comma
over north central Ga just about dead on.
JY
I mean…Lying more NE-SW…
HPC still showing the 1.5+ amounts Blue Ridge and west — drops off quickly eastbound.
http://www.hpc.ncep.noaa.gov/qpf/fill_94qwbg.gif
18Z NAM still big on heavy rain in zone along Blue Ridge from NW NC to Roanoke area. 18Z GFS not nearly as heavy — looks more like Blacksburg Mike’s idea of .75-1ish in SW Va.
0Z runs out soon.
It looks like I was off about where Roanoke’s rain is gonna come from, at least in the next few hours. From Statesville, NC (Junction I-77 and I-40). Looks to be on a direct path to Big Lick. Then the stuff from the Dothan, Bamalama and Macon, Ga (which joe mentioned) and maybe some stuff from Tenn. moving more easterly. Meanwhile the downspout just outside this window has been “running” for the past 30 minutes from some very localized stuff. HOW’D THAT HAPPEN?!?!? The former Mayor of Brownsville is one of the lucky ones this time? Will wonders never cease …..
I am just under 6/10ths of an inch. yay.
That localized showery stuff working up the Blue Ridge is part of why I think Roanoke ends up with a higher total than Blacksburg — and Doug’s house (and probably mine too) gets more than the airport.
Leo Lady, do you live within a mile of Fishburn? I used to walk Blondie Boy there when he was a very young dog, and especially our former dog, Cindy. We lived in a rental house at the bottom of Woodland Road, directly across Colonial Ave. from the Jehovah’s Witness facility. From Oct. 1997 through Jan. 1999. {Which is why I never saw snow during Jan. and Feb. of 1998}
The next time the sun comes out, my yard is going to look like Oz …… the Emerald City.
It is really pouring here right now. Am I headed for 1.5 or even 2 inches? Stay tuned.
wd, how are you doing up there on “Da Knob?”
Blacksburg Mike and the rest of you Montgomery and Pulaski County friends …. get ready. Big rains fast approaching your area.
My 9:03 comment has an obvious senior moment mistake. I intended to type about whether anyone wanted to bet against KM’s belief that ROA will get more rain than BLACKSBURG.
Just posted a new blog entry for overnight and Tuesday. I’m not doing an all-night vigil, but will try to get comments approved early Tuesday and any updates as needed.
A steady rain here in Hokieburg. Half an inch in the rain gauge.
Rainfall, so far, not that impressive at my location in Blue Ridge. As of 11:15PM, I’ve gotten 0.27″ since midnight. However, current radar indicates another slug of heavier rain is headed my way.