UPDATE 12:20 AM, 8/8: Some signs the summer heat may be beginning to lose its grip a bit
UPDATE 12:20 AM, 8/8: No major changes. Some locations from Roanoke south and east might scrape 90 Wednesday and Thursday. Friday may be a stormy day, with severe weather possible, as the cold front cuts into the thick humidity. I will follow up on this in later blog entries. Meanwhile, here’s something else to chew on: Wednesday’s Weather Journal column about the lack of tornadoes in the U.S. this year, especially since mid-April. END UPDATE
A cold front is sinking through our region overnight and Tuesday, bringing somewhat cooler air, though not much less humid. Showers and storms were not as widespread as projected Monday, but there could be some showers and storms any day this week, though the chances will better to the south and east in thicker moisture, at least through Wednesday. Highs will mostly stick in the 80s this week — though Tuesday will probably be more like mid 70s to low 80s, similar to Monday’s 76 at Blacksburg.
In the bigger picture, there are certainly some signs that the vicious central U.S. heat dome may be starting to lose its grip. It is backing up into the western U.S. the next several days, with a southerly dip in the jet stream digging into the Great Lakes and Northeast. That may be enough to allow the strongest cold front since June )before the heat wave and derecho) to slide through by the weekend. Forecasts are going to hedge toward the typical seasonal pattern of the front getting hung up and not making a clean push through, but if it can slip through as some models show, a day of widespread 70s highs/50s lows would be within the realm of possibility. Beyond the 6-10-day period, there is little model agreement on where the weather pattern will go. The Climate Prediction Center favors a low probability of above-normal temperatures for much of the East in its 8-14-day outlook, with the heat dome vacating the central and western U.S. entirely, but the CPC also notes a confidence level of 1 on a scale of 1 to 5 in that forecast. Model confusion in the long range is sometimes a signal of drastic changes in the weather pattern, but keep in mind that this is August, when quick and large changes usually do not occur so rapidly, especially with such a large-scale heat wave and drought under way over much of the nation. We can’t be sure yet whether much of August will end up being cooler than normal for us or at least seasonably hot, but for now, it remains obvious that the 100-degree stuff — and even most of the 90-plus stuff — will be staying away from Southwest Virginia throught at least the next week.
August 7, 2012 - 1:02 AM
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Thanks KM. See what the culprit is if you have time. I’ve had several posts rejected and I think it was a time limit thing. As in starting a post, having to stop and restart later before sending.
Is RRA the only official site for weather in Roanoke County? Are any measurements/data from area VDOT stations used?
I know WDBJ has the only snow board.
Coming soon…to a season near you.
http://1.bp.blogspot.com/-LpLVsdDWsPw/Tzq8rLZcPnI/AAAAAAAAKjw/W2AKgSDo5MA/s1600/Copy%2Bof%2B12%2B12%2B1949%2Bice%2Bb.jpg
Kevin, why is Friday severe weather day for Virginia?
http://www.cpc.ncep.noaa.gov/products/predictions/threats/hazards_d3_7_contours.png
Rick: That’s when the Canadian cold front punches into all this moisture — with possibly some stronger winds aloft with an upper-level low. Seems to me like it has a pretty good chance of being one of these jump-the-gap things with big storms to our west, then re-forming to our east. But details like that aren’t discernible this far out.
For National Weather Service climate purposes, wd, the airport is the major station. There are some co-op stations scattered around that are used to augment climate statistics in some usages.
I know co-ops supply reports for precipitation for county readings at individual locations but haven’t seen any temp readings from them. So, are the precip readings averaged in with the NWS data or simply provided as an unverified service? You also see VDOT stats listed. Same deal: not certified readings?
I’d like to see VDOT take precipitation records. Instead of 4 men standing around watching one guy with post hole diggers, 4 men would be standing around the rain gauge watching it fill up. lol
You ask some questions WD I need to get better clarification on. I also haven’t asked about your timing out thing regarding comments. Remind me about that in a day or two if you haven’t heard (not been in the office, or even on the computer much, last 4 days).
Well the weather in the Chapel has been uneventful this evening. Went to Saltville and played Church League Softball (acutally kept the bench warm tonight). Had some scattered showers today but nothing serious. The skies tonight have really been lighting up off the storms around Wytheville. Was still a bit muggy this evening. It has been nice for the heat to abate a bit. Maybe August will end up being more tolerable. Dog days continue wet.
I checked today’s CPC multi-day forecasts, just to see if they are still showing the 40% chance of the eastern states being warmer than normal 8-14 days out. They are. That’s their story and they are sticking with it. ……… At least until tomorrow.
What do you think, Kevin, Quags, Joe, Rick, Other John ….. will they be “eating that forecast/outlook?” Or do you think that they will be right? I fully realize that anything over 5 days can be subject to change on short notice. I’ll be a pessimist and say that they will be right.
I think it’s possible we could bounce back to 90-95 type heat (talking Roanoke and eastward) a few days next week after the weekend cold front. That would be considered enough above normal to verify that forecast. I don’t really foresee prolonged below-normal temps on the way.
The important thing about that outlook is not so much the shade over the East, but that they are projecting a singificant weakening of the central U.S. heat ridge.
Kevin, besides just the temps being higher on average this summer, what has the humidity been like. Has it been higher than usual?
Here is a handy tool for keeping an eye on rainfall and flooding. I don’t know if anyone has used this before, but it is pretty simple.
http://72.66.190.197/Virginia_IFLOWS/
Trevar, I don’t have enough long-term data to know what is normal for humidity readings (or, as I prefer, dew point). But dew points have been mostly mid 60s to lower 70s since the latter days of the early June heat wave. That would seem to be higher than what I would expect to be normal — and definitely played a role in holding our low temperatures upward even when our highs would drop off a bit for a few days.
Tina, you don’t know about snow holes until you live in the Ellett Valley. It can get seriously frustrating here sometimes. Now, sometimes I’ve been through Shawsville and Elliston (which is I believe where you said you live) when it was snowing in Christiansburg so I see your point. But numerous times that it looks like it will snow here in the Ellett Valley, it doesn’t. A few times it has snowed in Blacksburg 2-3 inches and down in the valley was only rain. Also, snow totals pick up vastly when I head up towards Blacksburg.
You and I have very similar snow hole problems it seems. We’re probably around the same elevation (1550 ft) and I know the Ellett Valley connects to North Fork and Den Hill road which both connect to 460 at various points and cross over and under I-81. So we’re also probably 10 minutes apart separated by the Paris Mountain chain based on my assumption.
By the way, another foggy morning!!! 7 of 8 days now!!!! And Doug, didn’t you say December 12 would be that famous foot and a half or some outrageous amount that was predicted 10 months in advance?
And sometimes Tina, the Ellett Valley is also a rain hole. Sometimes, it looks like snow or rain is directly over us, but it is just virga on the radar and we get nothing meanwhile Blacksburg gets everything.
One perk about living in the valley though is that it gets pretty cold in the morning from radiational cooling at night if there are clear skies.
Here is todays discussion of the newest pearl
crawling off the West African coast..
This is the area we mentioned yesterday.
A LOW PRESSURE AREA ASSOCIATED WITH A TROPICAL WAVE LOCATED ABOUT
700 MILES WEST-SOUTHWEST OF THE CAPE VERDE ISLANDS HAS BECOME
SLIGHTLY BETTER ORGANIZED DURING THE PAST SEVERAL HOURS.
ENVIRONMENTAL CONDITIONS ARE MARGINALLY CONDUCIVE FOR GRADUAL
DEVELOPMENT OVER THE NEXT COUPLE OF DAYS. THIS SYSTEM HAS A MEDIUM
CHANCE…30 PERCENT…OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS AS IT MOVES WESTWARD AT 10 TO 15 MPH.
This could become Gordon if conditions
remain favorable..
Even Florence isnt completely washed out yet.
Nick, It depends on where you live in Ellett. The configuration of Paris and Hightop mountains as perpendicular to the rest of the mountains have given me some interesting weather. For example, my little valley had a flash flood on Jul 15 with around 3 inches of rain in 20 – 30 minutes. And we’ve been getting LOTS of rainy thunderstorms. Other summers, I’ve watched all the thunder heads go to the other side of Paris and Hightop. I’m at 1900 ft. The elevation makes a difference. It is often raining at my house and dry on the valley floor, or snowing at my house and raining on the valley floor.
Nick,
When I lived over in Pembroke we had a problem with that also. I finally figured that the New kept a warm pocket around Pembroke, which I hated because Pearisburg and Newport always had a few more inches then us! I remember being so jealous as a kid. I am really jealous now living in Greene where it hardly ever snows and the folks back in Giles telling me about snow weekly.
Nick…sounds like we do have similar problems with snow/rain holes! I am actually not on 460 myself. Ft. Lewis is between me and the 460/11 corridor. I’m in Bradshaw proper, but because Bradshaw has no post office we have an Elliston address. I’m in the valley with Paris Mtn. to one side and Ft. Lewis to the other. And you are right, we are at almost the same elevation…I’m at about 1500 ft. It can snow in C’burg and we won’t get any…it can snow down toward Masons Cove and we won’t get any. I’m still blaming the landfill.
No fog here today.
Finally reasonable humidity in Blacksburg, 64 dewpoint, dwon from the almost constant 72-73
Kevin…and others..
Here is an analysis of some of the
weather factors in Air France crash.
They flew into the tops of thonderstorms
and iced over airspeed instrumentation (pitot tubes)
Thought this might be interesting with some of the other
discussion here and as we are cranking up the tropical storm
season.
http://www.weathergraphics.com/tim/af447/
Nickster, that infamous, outrageous, terrible Dec. 12th snowstorm prediction was for last year. I made it in Feb. 2011. By all means pick December 12th this autumn if you think it may happen this year. NOTE: In the snowfall prediction contest of November 2008 for the winter of 2008-09, I predicted that ROA would get 43 inches. I was only off by a one winter!! LOL. So there is a precedent for me to be deadly accurate, only for the wrong timeframe.
And I have to disagree with what you posted a couple of days ago about this summer getting a bad rap. And it is because you and I live in two markedly different locations. I can absolutely believe that in Ellett Valley this summer has been pleasant on many occasions, even after June 20th. At least when I have been in town (I was out of town twice since then), Roanoke valley has been for the large part sticky and hot or at least it felt that way with the high humidity levels. It has not been too bad since I returned late Saturday, but late yesterday afternoon and this afternoon got toasty.
The CPC multi-day forecasts are STILL showing the same things, normal temps for Virginia on the 6-10 day (Aug. 14-18) with the big heat well west of the Mississippi River, and all the eastern states in the 40% chance of being warmer than normal on the 8-14 day. I can live with that, because after August 16th I will be working very little (just a day or two here or there) until after Labor Day. And it will be on a riding route on the individual days that I do work.
CPC also sticking with this line in its forecast discussion:
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 1 OUT OF 5, DUE TO FAIR AGREEMENT AMONG THE MODELS AND POOR AGREEMENT AMONG THE TOOLS
Kind of a head-scratcher for them, and they’re making a best guess. But most signals are pointing to a significant reduction if not outright collapse of that central US heat dome.
Nick and Tina – I agree that elevation has something to do with rain/snow holes. I figured that the Doppler is on the highest point for around here and I do think storm cells/systems coming from the west are deterred either north or south of the ridge here by the elevation of the ridge. I am at 2546 ft and I believe the ground where the Doppler is located is at least 2700 ft. We have had 5 foggy mornings so far this month.
Also – have been sitting outside and just before dusk, we could see these really tall thunder clouds off to the southeast. Came in and looked on radar to see where they were and they were from Farmville to the east of Danville and down towards Raleigh/Durham. Amazing we can see clouds that far. Saw another batch of tall clouds the other evening north of us and thought they would come this way but radar showed they were up in Botetout County.
By the way, the drought monitor map of last week (July 31st … newest one is released tomorrow) had good news for two parts of the country. The Southeast, including most of Georgia, So. Carolina, and a good-sized chunk of ‘Bama (in the eastern section) are expected to have drought conditions improve, and impacts ease. The other big area is Arizona and southeastern Utah.
I have not followed it every week, but I have looked at those drought maps at least once a month at least as far back as April, and at least part of Georgia has been D3 or D4 every time I looked.
However, I should also add that the improvement may take many weeks if not a month or two. The period covered extends through October 31st.
Sounds like they’re betting on this El Nino pattern getting going by October. We’ll see.
Talking about elevation, the Chapel sits at approx. 1900 ft and Abingdon sits at 2050 ft. They sometimes get more snow sticking than us when it is a marginal/temp situation. However, due to the influence of the TN Valley they sometimes will have rain and we have snow. The trees and flowers are usually up to one week earlier than ours in the spring and there is a dramatic difference between the Chapel and Bristol. We also tend to be 1-2 weeks behind Roanoke and we are close to Christiansburg in terms of the spring sprouting.
Dopp Carol…
You are describing exactly why the Feds
chose FCX as the Doppler site in your area..
It provides a great view unobstructed half way
to the beach.
Its a huge tool for help for folks like me..
It helps for my flight planning for much of the area
from Atlanta to Washington..
The airport and flights into Charlotte rely in a big way
for flight planning in and out of there especially from the north.
Ill bet not many people here remember the old radar when it was
located in Volens. In those days the mountains created too many problems..and it seems they picked a high knoll south of Brookneal
so they could “paint” the weather from the coast to the mountains.
A lot has changed…and you are in the center of a pretty big universe.