Sunny, warm, dry weekend good for outdoor plans, not good for fighting wildfires
What will be a spectacular weekend for many folks with outdoor plans — dry, sunny, warm – will be a continuing nightmare for firefighters working on more than 20,000 acres of wildfires in the mountains of Western Virginia. (Inset at right, and linked here in full size, an aerial photo of the Barbours Creek fire at the Alleghany-Craig county line, courtesy of the U.S. Forest Service.) Dryness is a growing problem for Southwest Virginia, but it is worse almost everywhere north, east and especially south of us, as shown on the most recent Drought Monitor map of the Southeast U.S. Rainy periods around March 16-20 and March 23-25 that affected our region more than other parts of Virginia have kept us out of the “abnormally dry” zone, the first stage of drought, that covers most of the rest of Virginia. Some of southeast Virginia has already been upgraded to moderate drought, and states south of us have lots of moderate to severe drought ongoing. Whether that has a chance to lapse into a severe summer drought depends a lot on whether we can get more of the typical “April showers” and May rains in the next several weeks. Our chance of getting significant rain in the next week depends on a cold front moving through the central U.S. now. It is triggering severe weather on this Friday evening (tornado confirmed with damage in Norman, Okla.), and a large tornado and severe storm outbreak possible on Saturday. This front will make grudging progress our way, with some waves of low pressure moving along it, aiding in the growing southerly wind flow that will push temperatures into the 80s across most of the region by Monday and will also gradually re-moisten the atmosphere. This evening’s Hydrometeorological Prediction Center rainfall map through Wednesday evening suggests half-inch-plus amounts will be possible across Southwest Virginia. There will probably be some storm threat too, though probably not nearly as bad as Saturday’s in the central U.S. Rain would be good in fighting fires, but lightning can spark new ones.
Highs will top 70 over most of Southwest Virginia Saturday and some, including the Roanoke Valley, will likely top 80 on Sunday afternoon. Most will top 80 on Monday.
April 13, 2012 - 6:56 PM
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It looks like my prediction that April 1-15 would average cooler than March 10-25 did will verify. March 10-25 averaged 61.8 degrees in Roanoke. April 1-13 has averaged 57.1 and projected temperatures of 73/43 and 84/55 raise that only to about 58 degrees next 2 days.
Comparing the first 13 days of April to the hottest 13-day period of March (March 12-24), the March period is hotter by a landslide — 7 1/2 degrees, 64.6 for March 12-24 to 57.1 for April 1-13.
Doug Griggs asked earlier in the week about the role of tree canopy in wildfires. A forestry official noted in an article we had in the paper this week that a fully leafed-out tree canopy holds humidity higher closer to the surface, which can retard fires somewhat. If you notice, the worst fires this week have been occurring in higher elevations north and northwest of Roanoke, where the trees are not as leafted out as they are here in the Roanoke Valley and other lower elevations.
One of the things i remember that Kevin pointed out from the early days of this Weathre Blog was how the drought of 2007 (for Virginia and other Atlantic seaboard states to our south) was caused by a common/persistent storm track in the central and eastern USA that had plenty of rains in the Miss. Valley region, but instead of migrating east, tracked NE and generally stayed west of the Allegheny mountains. Most of West Virginia (except maybe for Mercer and Greenbrier counties and a few others that border SW Virginia) got ample rains, and so did Penn. and the Northeast. Track was up the Ohio River valley and on into the Norhteast, missing Virginia and the SE mostly.
That general pattern has already happened a couple of times this spring, including recently, and it’s one thing I try to keep an eye out for, especially now that the leaves are out on the trees and they will be sucking up a lot more moisture from the ground. So far our corner of Virginia has been relatively fortunate, compared to that drought map KM displayed. But instead of the folks already in drought getting better, I am afraid that SW Virginia will be joining them by getting drier.
Doug, I was in Front Royal on Tuesday. It is WAY dry up there! Where we are I think is the least dry part. The northern and eastern parts of VA are in trouble though…I was in Charlottesville, Richmond, and Williamsburg on Sunday and Monday and it was on the dry side. On Monday and Tuesday, I was in Fredericksburg and DC area and it was even drier. I would like it to rain but not on my golf days of Tuesday and Thursday and possibly on the weekend.
The map linked in the blog post above (and again below) shows that we are the least dry part of the entire Southeast region (as defined by the Drought Monitor, to include Virginia), except for central/northern Alabama.
http://blogs.roanoke.com/weatherjournal/files/2012/04/DroughtSoutheast0412.png
Not very sunny this Saturday morn up here on the ridge. It has been cloudy most of the morning and the temps are at 65 currently. Radar shows showers out in Kentucky. Will they make it over the mountain to rain on us or is our air too dry for that to happen just yet?
Anyone else watching the streaming video cams of the mid west storm chasers? Going to be an interesting afternoon on the high plains.
I concur with the current mood here that we are trending dryer along with everyone else. It has me pretty concerned.
If I watched too much of that stuff, I’d probably (1) not get any work done in the office tonight and (2) be antsy that I wasn’t out there myself right now. (1 month from today, perhaps). But I am keeping an eye on the overall situation.
HPC has upgraded our rain threat for midweek some. This is for Tuesday evening to Thursday evening.
http://www.hpc.ncep.noaa.gov/qpf/95e12p48iwbg_fill.gif
Kevin – keeping my fingers crossed for that rain heading this way.
Nate: I did watch some of the chaser streaming video when the tornado was closing in on Salina KS. Glad it lifted before getting there.
Kevin, thanks for posting that link to the HPC outlook map. Just about all of us hope that it “verifies,” as you and now I like to say. Or even outperforms that. But it is in direct disagreement with what I heard a television meteorologist at Channel 19 (CBS affiliate) in Charlottesville say on their 11 PM newscast last night (I am back home now after spending last night in Hoo-ville). He claimed that the latest models he looked at showed the midweek rains either petering out or missing Virginia entirely, I think the latter. But the HPC forecast is at least more recent.
But as I bet you will point out once that system approaches, even assuming that it does come here, it will have to overcome very dry air at the lowest levels of the atmosphere, especially the further northeast in old Virginny one travels. We could have several hours of virga. By the way, is it forecasted to pick up some Gulf moisture? I hope so …. those tend to be much more loaded.
I’m not sold on these bigger amounts yet. The issue won’t be Gulf moisture — this storm is tapping lots of it. But the better lift and dynamics with the storm system will likely go well northwest of us. That would spare us a lot of severe weather, but also keep the rain away. There is some chance a second area of low pressure develops along the front and ripples northeastward. That would increase the rain potential.
The 3rd sentence of your 9:51 comment is what happened way too much in 2007, right? Storms missing SW Virginia to the west and NW??
Sorta similar, Doug, except that started happening in January.
Dangerous situation for Wichita now with a large tornado moving toward a major metro area. Hopefully, it will lift before it gets there.