UPDATE 11:45 PM, 4/18: Significant rainfall continuing today; an even bigger soaking rain likely by weekend
UPDATE 10:45 AM, 4/18: Many locations in Southwest Virginia, and farther north into mountain areas suffering wildfires, have already seen rainfall amounts of more than a half-inch (dark blue colors on this radar map) with rain continuing to fall on this Wednesday (current radar linked here). Some locations, especially along the North Carolina border in Grayson and Carroll counties, have seen more than 1 inch, more than 2 in some cases. The map I have posted at left shows the potential for 2-3 inches of rain areawide — and it has absolutely nothing to do with today! This is the newest Hydrometeorological Prediction Center rainfall projection map for the weekend (8 a.m. Saturday to 8 a.m. Sunday) in conjunction with a major eastern U.S. storm system. Today’s rain is substantial and very much needed, but it remains but a preliminary act to what is likely to be a weekend soaker — though one that still appears likely to occur mostly after Saturday morning’s marathon in Roanoke, with some other weekend activities having a few dry hours during the day Saturday. END UPDATE
UPDATE 11:45 PM: Rain has been overspreading the region from south to north through the evening, and this will continue overnight. Some locations near the North Carolina border have already got over an inch of rain, but dry air has stymied the rainfall farther north. The atmosphere will continue to saturate more in the overnight and early morning hours. Rain falling through dry air will also cool many areas into the upper 40s and low 50s, and temperatures will struggle to rise on Wednesday with rain continuing. END UPDATE
UPDATE 9AM: Let’s take a new look at the 5-day precipitation map from this morning. Rainfall amounts through Wednesday evening have been upgraded to 1/2 to 1 inch for much of Southwest Virginia as a wave of low-pressure develops along a stalling front and throws moisture back over us. The map shows heavier 1-plus-inch rainfall developing over western Virginia in the 48-hour period ending Sunday morning, as well, with the possible strong low-pressure system we’re discussing. It appears the best shot of rain the next 36 hours or so will be Roanoke and southward, while the wildfires are mostly to the north. So count us in for 2 possible periods of substantial rainfall in the next 5-7 days or so. END UPDATE
A strong storm system and cold front in the central U.S. has been the focus of recent days, especially after Saturday’s severe weather outbreak. And that cold front will pass through Tuesday and hang up into Wednesday, providing a focus for some scattered showers and thunderstorms, and also knocking some degrees off the summerlike highs we’ve experienced Sunday and Monday (89 at Roanoke on Monday, 1 short of the April 16 record from 2002; 81 at Blacksburg, tying the 1994 record for the date). Though we may warm up close to 80 again in some places after the midweek showers, Monday was likely the last summerlike day we’ll have for many days, maybe weeks.
But for Southwest Virginia, this storm system may be upstaged by what could turn into a powerhouse spring storm for the weekend and early next week. Forecast models are converging on the development of a strong low pressure system near the Gulf Coast late this week, moving north or north-northeastward, over the weekend into early next week. If this occurs close to what is projected, our region could be in line for a soaking rain (the map linked here is only through Saturday evening), as moisture would be drawn over us from both the Gulf of Mexico and Atlantic Ocean. Severe storms would also be a possibility if the storm takes a more inland track and we end up in the “warm sector” east of the low. The low may also wrap in enough cold air for high-elevation snow on its backside. It is possible the low will move very slowly or even become so wrapped up it is pulled more to the west after it moves north of us, so this could be a prolonged episode of showers, storms, wind and eventually some unseasonably cool weather into next week. Much remains uncertain in regard to the development and timing of the weekend storm. Many in the Roanoke area will be concerned about Saturday’s third running of the Blue Ridge Marathon, which was damp 2 years and absolutely soaked a year ago. There is some indication at this time that the rain will not get going in earnest until late Saturday, so don’t write it off as another soaker just 
yet. The weekend rain will be very beneficial for ongoing forest fires in the mountains north and northwest of Roanoke — here is a photo I shot of smoke and “pyrocumulus” clouds from one of those fires on Roanoke’s western horizon, as seen from the Mill Mountain Star Overlook this evening.
There are some indications a cooler overall pattern may close out April and move us into May, as blocking high pressure possibly develops over Greenland and near the North Pole, features missing during most of our mild, nearly snowless (except Feb. 19) winter. The correlation between these features and the onset of cooler than normal temperatures diminishes the later on the calendar we get, as the mean jet stream position lifts northward, but it could still be enough to induce cooler weather in mid-spring. Plus, we’ve been so warm relative to normal for much of the last 5 months or so, that even just “normal” would seem cool.
April 16, 2012 - 11:45 PM
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Neat shot of the pyrocumulus clouds!
I’ve been watching the Rich Hole fire from my deck near Clifton Forge. Didn’t know that those clouds had a name — pyrocumulus. Here’s a link to a time-lapse movie I took on Saturday showing the smoke billowing up, then hitting a shear layer and getting spread out.
http://dl.dropbox.com/u/62299864/Rich%20Hole%20Fire.m4v
Morning models seem to be more progressive with the weekend low, and generally on a coastal or just-inland track. That would mean more general rain and less severe risk for our area, and moving on out rather than hanging around for days. Euro model still wrapping in more cold air than GFS, but not at the same level as it was yesterday. Inland New England could have a substantial snow threat, with some backside upslope snows in the higher elevations of West Virginia. Still a developing situation, and still likely to be introducing a much different weather pattern than what we’ve seen in March/most of April.
are you still thinking the timing of this weekend’s rain as “late Saturday”…. I know this is all subject to change, but wanted to see what your current thoughts were
Right now I would say showery on Saturday morning, with heavier rain late Saturday and early Sunday. The more progressive nature of the storm system might mean a quicker start, though, as opposed to the slower moving, more wrapped-up storm on earlier models.
Well I can tell you this, the rain hog is needing some rain now. Not as bad as my friends to the north and east but needing some rain all the same. Hoping for it tomorrow and this weekend if that is what it takes.
My garden NEEDS rain, so I say bring it on LOL. Now I will duck as Mr. Griggs may not appreciate being out in the weather if he has to walk on those days :>)
Something very rare on Monday: Roanoke was only 4 degrees off the national high temperature. Those were at Quantico, Va., and Westfield, Mass. … yes, Massachusetts, warmer than anywhere in Texas and Arizona … at 93.
COME ON RAIN!!
A training line of cells now coming out of NC heading towards Galax and on the right trajectory to make it to the ROA valley. “Lightning Finder” showing some returns on these.
NWS upped the precipitation amounts. They’re now saying half to three quarters tomorrow alone.
NWS has, ever so slightly, lowered Saturday’s rain chance (from likely to chance). Is that to more align with the bulk coming later in the evening/night?
The 9 a.m. update on this blog entry does touch upon the raised rain totals.
As for any storms this evening, with the front settled along the Virginia-North Carolina border, our atmosphere has stabilized substantially. Dew points are running low 40s to low 50s, any meaningful wind shear and CAPE (convective available potential energy) are clustered in western North Carolina. Certainly some thunder may occur but the threat for any severe weather looks very, very low for most of SW Virginia. The Storm Prediction Center has the light green thunderstorms possible area barely nipping across the Va-NC line in one place, with the slight risk for severe weather generally Charlotte to Atlanta.
http://www.spc.noaa.gov/products/outlook/day1otlk.html
Brian: NWS definitely thinking more Saturday afternoon and evening with rain/storms, judging by latest forecast discussion.
Roanoke’s dew point has slipped to 36. It’s going to take a while to moisten things up this evening, and that process is going to drop temperatures into at least the low 50s, maybe upper 40s. And much of Wednesday will be that raw.
Now NWS has went back down to quarter to half inch for me in Rocky Mount. I guess we flipflop in every season, not just with snowfall totals.
Matt ~ did you see WSLS’s weather? Their map showed 1.10″ through Thursday. Big difference between the two…
Been meanin to ask this for awhile. If the temp and DP are the same for two different locations but the elevation is 1,000 feet different, will the RH be the same? And if the temps and the RH are the same, will the DP be the same, still 1,000′ difference in elevation? Mainly talking about our local area.
WD: Elevation does not affect the calculation of relative humidity. Same temp/dew point at 1,000 feet and 2,000 feet will yield same relative humidity. Same temp/RH at those elevations will yield same dew point. What may be different, however, is that the site that’s 1,000 feet higher may have less dry air above it than lower site. So the higher location may moisten/saturate earlier, see precipitation earlier and have dew point/humidity readings rise quicker. This is commonly the case in our region with rain/snow events moving into a dry air mass.
Thanks KM. Sawvwhere ole Dan[dirty dan mcgrew]Casey just won an award for the Times. Think they switched your name and face for his and the judges didn’t know any different.
Little known fact: Dan Casey hired me in 1999. Hired my wife too, long before she was my wife. So I’m certainly not going to begrudge Dan winning an award.
There aren’t really many categories of awards for weather bloggers.
He jest went up a notch in my book fer showin fine judgement.
Michael Hoback needs rain??? Are you kidding me? Go visit Winchester and/or Front Royal and be grateful, as I am. …….. Just teasing, MH! You are gonna get a very healthy amount both tonight/tomorrow, and over the weekend. Shanon, Nurse “Dry Garden”, don’t worry about me, and thanks very much for your kind thoughts. Yes, I will have to deliver both tomorrow and on Saturday on walking routes in the rain, but BRING IT ON!!! As Spock said in Star Trek 2, the needs of the many outweigh the needs of the few, or the one.
Kevin, in reply to your 5 PM comment. Thanks for talking about tomorrow, and informing us what is REALLY gonna happen ….. raw east wind and I bet Roanoke temps will struggle to get much above 50, not the 57 or 58 that WDBJ7 and the NWS are mentioning. Where I will be tomorrow an east wind really is very cooling on a couple of the streets. Those two organizations are talking about wind speeds around 7 or 8 mph. I wish. I bet some of my fellow letter carriers and I will at many times be walking into an E wind of 14 or 15. If temp is not above 50, that translates into a substantial wind chill. I hope that I am being too pessimistic …. but I have seen this scenario play out before, including earlier this month.
This is one time I hope that I am very wrong, and that I will be wrong on the cooler, windier side.
Ok Kevin, i am getting married in Cape Hatteras the week of April 28 thru May 3. The wedding actually being on May 3. Could you give me any idea of what to expect?
Casey won an award. WoW ! ! What a shock, NOT !
Liberals are always honoring each other. That should get them into heaven. LOL ! ! Just heard today Wm F. Buckley never won a Pulizer. Nuff said ! !
Seeds are in the ground, let it rain !!
Glad to hear the rain running in the gutters. Spent all day in the garden and yes – it is a “dry” garden. I could not believe how far down it was dry. Let it rain, Let it rain!
Casey is a bit liberal for me… gotta agree with Peppers Ferry…BUT… I like how he put Spanky front and center! Kudos for that. Sprinkling rain here near Rocky Mount right now. Let it rain!
Had light rain on and off most of the evening, it’s been nice to see. The yard was starting to show signs of dryness, but that should be pushed back some by tomorrow.
Jason, in response to your 8:32 comment, which you ended with the Q: “Could you give me an idea of what to expect?” Congrats on getting married, first of all. Poor gal ….. oops, I mean “Lucky gal!!”
What to expect?? Years of you saying “Yes, dear,” and being outnumbered 1 to 1 when she and you have different ideas about what to do or how to handle a problem ……
What a great day today,cooler temps I was at Dulles Airport when Discovery Landed and taxied down the runway people were going crazy on the tarmac taking pictures and video.At least 1000 people out there watching history being made.Wow can`t believe i was there to see this.I work for Pepsi and i had to go to the midfield terminal to work on a couple of Fountain systems.I was parked on the Tarmac as the 747 went by with Discovery.It was to cool to be there!
As soon as you get there, look up Kenny Wilson in Frisco and book a trip with him. Should be some red drum or cobia around. Always sharks and AJ’s. Do this 3 times before the 27th. Watch your girlfriend closely and see whether she likes it or not. She won’t be that good at pretending she likes it after 3 days. If she loves it, move the wedding up to the 28th. If she don’t and throws a snot fit, get outta town on the 28th. BY YOURSELF!!!!!! Like Lucy woukd say, “That will be $0.05 please”.
51 degrees and exactly 1/2 inch of rain in gauge at 6:20 A.M.!! Nice.
Ahhh – what a pleasant sound – rain running in the gutters. It is 44 F this morning up here on the ridge and we have had “0.75″ inches so far. The garden is loving it!
Mike in Marshall – a friend had a picture of Discovery – looked really cool and I would have loved to have been up at Dulles to see it land. A awesome sight.
We picked up a nice half-inch overnight, and it’s still raining nicely in the NRV. We may wind up erasing the rain deficit for April by the end of the weekend, pretty wild.
Forgot to mention that we are hearing rumbles of thunder and seeing flashes of lightning up here on the ridge. Radar shows rain heading north up along the mountains. Any word on if the rain is helping the forest fires?
Just had one big rumble of thunder here in Rocky Mount.
1/3 of an inch by 8am…the second batch put us at .60 for the day. High for the day, at Midnight, was 63.9. Currently sitting at 50.8
http://www.hpc.ncep.noaa.gov/qpf/95e12p48iwbg_fill.gif
This weekend is looking more and more like a washout….
Great minds run together, Flutie. Just posted the new weekend map in my new entry. Runs from 8 a.m. Saturday to 8 a.m. Monday.
But — marathon runners — HPC is showing NO RAIN through 8 a.m. Saturday, not even very close to us.
http://www.hpc.ncep.noaa.gov/qpf/fill_99qwbg.gif
So the race may get in before the downpour arrives. Perhaps some of Saturday daytime will be OK for other outdoor activities as well.
First time since March 15 that we have received precipitation today here in Greene county! Its so SWEET! Hope we can get much more this weekend!
Well, I’m glad I mowed the yard Monday…looks like it might be another week or more before I’m able to mow it again at this rate! Even if the rainfall comes in under those HPC maps, it should still be a good haul of 1-2″ for the week in most places. I’m betting that by the time the rain ends today, we’ll have gotten an inch or very close to it.
Just tipped the 1 inch mark in Goodview. We are, and have been, right on the very edge of the precip shield. We’ve had 1.03 so far, yet just down the road at Hale’s Ford Bridge they’ve received .52.
Surprised with so much rain that NWS didn’t put out a precip forecast map. Do they only do that during potention flood events?
At the lunch time hour, it is currently 48 F and we have had 1.47 inches of rain. Wonderful! Have collected 300 gals. of rain water – that was all the container would hold and it had started to overflow. Currently emptying that water into a holding tank so we can collect more.
Jared French – so glad to hear that you are getting rain up your way. It is also good to hear that the forest fires areas have received rain.
Kevin, so are you thinking the Saturday morning activities will be rain free? “Bark for Life” is happening up here Saturday morning and it would be nice to have a rain free morning for that.
Yes, Euro I’ll take it all.
Following up on Zach’s comment, this is the 0Z Euro map for Monday PM:
http://blogs.roanoke.com/weatherjournal/files/2012/04/Euro0ZMonPMmap.gif
The blue area represents freezing temperatures about a mile up, often good enough to support snow, overpsreading the entire area.
As we get into warmer seasons, the surface layer warmth sometimes precludes or at least interferes with snow making it to the surface even if it’s favorable a mile up. However, IF this solution verifies, this would probably become a substantial wet snow at higher elevations, 3,000-feet plus, especially west of the Blue Ridge. And there could be snow showers at even lower elevations.
Very dynamic storm we’re dealing with this weekend/early next week, maybe the most significant coastal/just inland Eastern US low since the winter of 2009-10. Snow fans will be wishing this could have happened in January with an Arctic air mass in place.
Right now I’m thinking Saturday morning is looking OK with showers moving in by late morning or early afternoon. That is subject to change, but if the storm is as wrapped-up as some models depict, it will also be a bit slower.
48.7* with something over 3/4″. D. Carol, I’ve been eyeballing the woodstove all morning. It will probably see service later today. Got in wood yesterday and a neighbor asked if I was expecting snow. I just laughed and kept loading. Little does he know. And I won’t be listening to a furnace run either. Been dropping since midnight and I don’t see any upper 50′s like the forecast calls for.
HOLY COW!!!!
To confirm Kevin’s analysis, we could have a monster on our hands for this weekend. Zach may be right if the ULL pulls down the colder air on the back side in time. If the Euro verifies, there could be some significant snow accumulations above 3000′ especially north of I-64.
What has me worried is the potential severe weather and flooding threat with this upcoming event. This bears watching.
Dave Tolleris has a great write up on his website home page. He does a very detailed and excellent observation of what is in store for this weekend.
http://www.wxrisk.com/
Wednesday’s 12Z GFS loop from PSU:
http://www.meteo.psu.edu/~gadomski/AVN_12z/avnloopnew.html
12Z GFS is not as bullish and takes a coastal track to the east, not inland like the Euro. GFS takes most of the weather more to the east thus diminishing the rain and severe threat.
I’m keeping my eye on this as well.
can folks weigh in with rainfall totals please?
Wednesday 12Z ECMWF update
http://www.meteo.psu.edu/~gadomski/ECMWF_12z/ecmwfloop.html
Euro tracks the low a little more east than last 12Z run from Tuesday and the 0Z run this morning. What is significant is the Euro is beginning to slow down the storm’s speed which means it could end up being stronger as Kevin surmised earlier. As I said from above, a more easterly track reduces the severe and flooding threat.
Any rain at this point is definitely welcome.
I’ve gotten 1.25 inch in south Roanoke County. I’ll post some areawide rqain totals later this evening.
One thing the models aren’t going to be zeroing in on much this far out for the weekend storm is the massive amount of upslope wind flow from the southeast and east that would occur with a low tracking up the coast or just inland. That will magnify rainfall totals in the western Piedmont and in the Appalachians, especially along the Blue Ridge.
Currently at 1.19 inches for the day in Goodview and a chilly 49.9
Up here on the ridge in the northern part of the county, it is 47 F. We have had a total of “1.53″ inches of rain. The garden is loving it.
wdbrand – just took a match to my woodstove. Nothing like a woodfire to take the chill out of the air. I am thinking we may need to bring in a couple extra armloads of wood before the weekend.
Here is a link to amounts across the region (may seem weird through Iowa Mesonet site, but it’s one of the best ways to link to products of weather service offices)
http://mesonet.agron.iastate.edu/p.php?pid=201204182140-KRNK-NOUS41-PNSRNK
Amounts generally 1/2 to 1 inch with some larger amounts, a few over 2 inches.
Yea, got me wondering if I should have brought in 2 loads yestiddy instead of one. And mine is going also. Temp came up from 68* to 74.1*. The highest I’ve seen today was a little over 50*. Currently 49.1* Around 0.80″ here sofar, and it looks like that’s it for this one. At least any heavy stuff.
New HPC 5-day rainfall map shows widespread 2.5-plus inches for our region through Monday evening:
http://www.hpc.ncep.noaa.gov/qpf/p120i00.gif
Less than a tenth of an inch of that comes this evening.
http://www.hpc.ncep.noaa.gov/qpf/fill_94qwbg.gif
Kevin-any idea why NWS is forecasting high temp of 61 in Blacksburg for Sunday, a full 10 degrees warmer than today? What models are they looking at? It will not get out of the upper 40′s at best on Sunday with snow flying after dark. People west of I-81 and above 2,000′ will see snow Sunday night, with accumulations above 3,000′ (look for Whitetop, Quinwood, etc. to pick up about 6″), and there is zero mention of it in the official forecasts?
Remember that it may be mild in the pre-dawn hours Sunday and fall through the day. HPC currently has 66 for a projected high at Roanoke on Sunday. (http://www.hpc.ncep.noaa.gov/medr/DAY4_MAX_wbg.gif) (OR .. is that 56 … I’m having trouble making it out) As for snow — most GFS runs and the 12Z Euro are not as aggressive with the snow as the 0Z Euro was, which if it verifies, might get some snow into Roanoke and even Greensboro. NWS does mention the possibility for snow in its forecast discussion. Upslope snow showers/squalls look to be likely in the mountains west of Roanoke, but what’s in question is whether there will be a true wraparound slug of the main moisture involved in any snow.
The GFS, taken literally, is not even as aggressive with the rainfall amounts for SW Virginia as the HPC is projecting. The higher totals are a result of (1) the Euro placement of the low, (2) expectation that the GFS shifts west with the track, as it almost always does with coastal lows 3-5 days out and (3) factoring in upslope E/SE flow into the mountains.
Hey, Farmer Bill, here is my rainfall total. Just about 1.5 inches for the entire event. 1/2 overnight, as I posted earlier, than another 0.8 inches by 4:30 PM, then close to another 2/10ths in the next 3 hours. I live up Sugar Loaf Mountain Road, about a mile from the rear entrance to Allstate (which is on SR 419/Electric Road).
I can hear Mick Jagger …. “But if you try sometimes ….. you just might find ….. you get what you need!!!”
I looked back at the thread started last Thursday, April 12th, entitled “UPDATE 11:50 PM”. I made a couple of comments at the end of that thread on late Friday evening.
wd, my “reverse snow dance” seems to have worked!! This system overperformed vs. the outlook just a couple of days ago, at least for Doppler Gal, you and me and folks close to the Blue Ridge SW of US 220.
I think/know that many of you don’t look back at comments from Friday night and Saturday and perhaps on Sundays, which is fine, but the very last one I made on that thread (at 10:25 PM Friday) described how dry the golf course was that I played that day in Front Royal, VA. It wasn’t just there. I also took a look at Winchester CC that morning, and I couldn’t believe how pale green the fairways and greens were (from lack of rain). Even some brown spots … in mid-April no less!!! Those two golf courses were the driest-looking courses I have even seen in the past three seasons at least, and I sometimes play in other regions of the US and Ontario, Canada. I was shocked!!
I got pretty wet today doing my mail thing, but loved it!!! We needed the rain! I don’t want ANYONE here in blogland to see conditions like I saw.
Kevin and Quags and anyone else following the models …. do any of them show any possibility that the Low becomes stationary just east of either the Outer Banks or Virginia Beach? If that were to happen, we just might have a sort of repeat of the “Ash Wednesday Nor’easter” of early March 1962.
And we wouldn’t want it, believe me. Not that much wind and rain, especially for the Outer Banks and coastal New Jersey. Devastating damage back then, but the price tag now would prob’ly be at least 5 times as high, maybe even a multiple of ten.
I received .80 in my gauge here between Rocky Mount and Smith Mtn Lake. Looks like it ended up being a bit more than was originally expected by CPC and NWS.
The tendency for the weekend storm is that if it becomes really wrapped up early and slows down or stalls, the “negative tilt” on the upper trough (the axis angled NW to SE, rather than usual SW to NE of positively tilted trough) would tend to pull the system more inland. It’s doubtful it would spin off the coast like Ash Wednesday ’62. It would be somewhat more likely to get pulled inland toward northern Va or western Pa/eastern Ohio, more like Appalachian Storm 1950. The level of cold air present is not as great as it was with either of those storms, so snowfall would not be as widespread as with either of those. Coastal flooding and erosion may be a threat in some areas along the coast, considering the strength and track. Right now, I’m betting on a classic coastal or slightly inland track, with its greatest deepening occurring in the Northeast.
One concern now is that the storm is a bookend to the October snowstorm for inland New England. As in October, a heavy, wet snow now with so much leafed out could be a disaster for trees and power lines they would fall onto.
Thanks for your thoughts, KM. Wouldn’t it be something if this system were to provide quite a bit of snow for some regions??! That would mean that two of the biggest snowstorms for this snowfall season (cannot call it winter) in the eastern seaboard states and WV would be in late October and late April! Totally weird.
We picked up about 1.1 inches of rain in Riner, southwest Montgomery County.
Checking in with a cool .80″ of rain here in the Chapel. Garden really appreciated it and if I had not gone to Church tonight, I may have built fire but I will hold off on that till Monday.
Doug Griggs – Thank you for doing your Reverse Snow Dance. Even though I love the snow, this time of the year I love the rain more. I did think of you out there working in the rain and want to let you know that I appreciate you delivering the mail.
1.03″ storm total in eastern Pulaski County, New River. A pretty good haul, the grass is quite thankful tonight.
Kevin, in response to the last sentence of your 1:17 comment about snow fans wishing this had happened during mid-winter, or 3 months previously. Well, some of us, especially me, wish this would happen three months in the future, in late July, providing a wonderful mid-summer cool spell.