JC-CT Posted September 9, 2014 Share Posted September 9, 2014 Did a bit of blogging about last week's tornado in upstate NY and the tornado debris signature. Another interesting case. Many borderline/weak tornado events have been able to produce TDSs in the northeast... probably due to how widespread/thick our forests are. http://ryanhanrahan.com/2014/09/08/another-new-york-tornado-debris-signature/ What do you think the reason is that the NWS is missing these TDS? I agree with the weak/strong/violent classification. Nothing more futile than trying to determine an EF-4 vs EF-5 based on crappy building codes. Link to comment Share on other sites More sharing options...
CT Rain Posted September 9, 2014 Share Posted September 9, 2014 What do you think the reason is that the NWS is missing these TDS? I agree with the weak/strong/violent classification. Nothing more futile than trying to determine an EF-4 vs EF-5 based on crappy building codes. Not sure - could be a training issue where some mets aren't comfortable using the products or another issue. Each case is different though and each radar operator has there own set of procedures they use. Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 I think I remember hearing of some study at some point that people tend to overestimate winds at the low end of the scale but underestimate it at actual high speeds. I'll second that. We always used to show video of a strong MCS in the Quad Cities spotter training, and asked the audience to estimate wind speeds based on everything they had learned so far. True wind speed was pushing 120 mph, 90% of responses were less than 80 mph. Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 I disagree about some "assigned" values that a study found. There are too many variables to just assign a value for trees uprooted. I saw a pine snapped from 50mph winds in Sandy. I saw plenty of trees snapped and uprooted from 60-75mph winds in the Feb 2010 windstorm. What is the soil like? Is it wet? Is it sandy? What kind of tree is it? Does the tree have a lot of leaves or little leaves? Does the tree have a lot of branches? Are the branches spread out on the tree or is the tree top heavy? Is the tree healthy? Is the core rotted out or the tree diseased? There are just too many variables. I've seen trees snap in 50mph winds and 90mph winds. I'm not saying those winds you claim didn't occur...but some of those values in that study seem awfully high. It's probably the best thing we have at the moment to judge, but common sense and experience casts a little doubt. There are just huge error bars on the EF Scale when it comes to trees. And the scale itself isn't a fixed thing, it's a moving target that is constantly being revised to use the latest research. I know I sat in on a webinar last spring about the EF Scale and trees specifically. The gist of it was that the scale is already flawed because some hardwoods act like softwoods and vice versa. On the Limington survey we actually we being led through the woods by an ecologist with a good knowledge of trees in the area. He called us because of the damage to the pitch pines in the area, which he thought was notable. They have a very deep root system to tap the more sandy soil, so uprooting them isn't easy. How do we account for that on the EF Scale? Bump it from expected of 87 mph to upper bound of 113 mph? Somewhere in between, if so where? Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 It's warned too. Right on the outflow....one thing I noticed (although hasn't happened this summer) is that the outflow from BOS harbor storms seems to fire up cells east of rt 24 and that's pretty much what happened. I've seen this many times. In fact i was excited to move there as that area to like srn ORH county is another semi good spot relatively speaking for storms. Not this year I guess. I think sea breezes often play into this as well. You have convergent sea breezes on the north and south shores. Likewise down in South County, RI and SE Mass near EWB. They are all spots where storms tend to flare up in my experience. Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 Not sure - could be a training issue where some mets aren't comfortable using the products or another issue. Each case is different though and each radar operator has there own set of procedures they use. Obviously this will get better with time. The new recruits to the NWS staff will "grow up" being trained on how to use dual-pol. The older generations were trained too, but you know that not everybody is receptive to change. I know here if I see an interesting case locally, I send emails to the staff to remind them of the utility of a certain product. But a lot of times it's this Eventually people are going to catch on, especially if it could lead to better results than we have been getting. Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 Speaking of storms, I just saw this headline thanks to Facebook's "trending" topics. http://gawker.com/chicago-fire-actress-molly-glynn-killed-in-freak-accide-1631773124 It's a terrible story for sure, but a freak accident? It was a severe thunderstorm, which I consider to be life-threatening. It bugs me a bit when things like this get downplayed. I would consider a freak accident being a meteor hitting you or something. If the recollection of the events are correct, that would also mean there was 43 minutes lead time before the storm reached the bike trail. Plus, Gino had 70 mph winds in the warning from the get go, a step up into significant wind threat. Maybe this is a good argument for why smart phones should alert for SVRs in addition to TORs and FFWs. Link to comment Share on other sites More sharing options...
CoastalWx Posted September 9, 2014 Share Posted September 9, 2014 There are just huge error bars on the EF Scale when it comes to trees. And the scale itself isn't a fixed thing, it's a moving target that is constantly being revised to use the latest research. I know I sat in on a webinar last spring about the EF Scale and trees specifically. The gist of it was that the scale is already flawed because some hardwoods act like softwoods and vice versa. On the Limington survey we actually we being led through the woods by an ecologist with a good knowledge of trees in the area. He called us because of the damage to the pitch pines in the area, which he thought was notable. They have a very deep root system to tap the more sandy soil, so uprooting them isn't easy. How do we account for that on the EF Scale? Bump it from expected of 87 mph to upper bound of 113 mph? Somewhere in between, if so where? I agree it's difficult. I guess my point is that even those lower bounds seem awfully high. Using rootballs and tree snap velocities are highly variable. The value in the PNS came as a surprise given the description. Anything over 100 is going to mow down a lot. Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 I agree it's difficult. I guess my point is that even those lower bounds seem awfully high. Using rootballs and tree snap velocities are highly variable. The value in the PNS came as a surprise given the description. Anything over 100 is going to mow down a lot. I agree. There are all sorts of nuances when it comes to sustained wind stress versus a sudden wind stress too. I tend to think 100+ you're generally talking about square mileage of trees downed, not the individual number of trees downed. Link to comment Share on other sites More sharing options...
CT Rain Posted September 9, 2014 Share Posted September 9, 2014 Obviously this will get better with time. The new recruits to the NWS staff will "grow up" being trained on how to use dual-pol. The older generations were trained too, but you know that not everybody is receptive to change. I know here if I see an interesting case locally, I send emails to the staff to remind them of the utility of a certain product. But a lot of times it's this Eventually people are going to catch on, especially if it could lead to better results than we have been getting. At least here I've been trying to get everyone on the dual pol bandwagon. For us it can be a huge competitive advantage knowing that the other stations probably don't use dual pol with their severe coverage. Much easier to pinpoint areas of large hail and even be able to "confirm" a tornado touchdown before the NWS does (depending on who's working at the WFO). Link to comment Share on other sites More sharing options...
bobbutts Posted September 9, 2014 Share Posted September 9, 2014 Speaking of storms, I just saw this headline thanks to Facebook's "trending" topics. http://gawker.com/chicago-fire-actress-molly-glynn-killed-in-freak-accide-1631773124 It's a terrible story for sure, but a freak accident? It was a severe thunderstorm, which I consider to be life-threatening. It bugs me a bit when things like this get downplayed. I would consider a freak accident being a meteor hitting you or something. If the recollection of the events are correct, that would also mean there was 43 minutes lead time before the storm reached the bike trail. Plus, Gino had 70 mph winds in the warning from the get go, a step up into significant wind threat. Maybe this is a good argument for why smart phones should alert for SVRs in addition to TORs and FFWs. It's akin to calling a shooting during a game of Russian Roulette as a freak accident. The danger of lighting is blatantly obvious. Another favorite of mine is articles that blame car accidents during a winter storm on the road conditions. Sure the road conditions are bad, but the cause of the accident is poor driving as always. I think if you start alerting for SVR then the result is people ignoring all the alerts, they are too frequent. Is lighting even considered in issuing a SVR warning? Even if you alert for severe, could still be no warning for a storm with very prolific lighting. Link to comment Share on other sites More sharing options...
bobbutts Posted September 9, 2014 Share Posted September 9, 2014 I'll second that. We always used to show video of a strong MCS in the Quad Cities spotter training, and asked the audience to estimate wind speeds based on everything they had learned so far. True wind speed was pushing 120 mph, 90% of responses were less than 80 mph. If you are in person this mistake won't happen much. I was cowered in the tub with all the windows blocked with plywood when I experienced easy 100+ with higher gusts and there was no mistaking the intensity just from the sound. Link to comment Share on other sites More sharing options...
tamarack Posted September 9, 2014 Share Posted September 9, 2014 Much of the information we included in the Public Information Statement (PNS) was offered in the interest of transparency, letting everyone know what we found. The 110 mph value is for the maximum damage found; per EF indicators, this is the expected value (not highest nor lowest) for maple trees that were snapped. Snapped pine trees have an expected value of 104 mph. Obviously not all of the damage was at maximum. Expected values for uprooted trees/rootballs is 94 mph for hardwoods(maples), and 87 mph for softwoods (pines). Expected value for large branches (hardwood and softwood) is 74-75 mph. Thanks. This is very interesting, and might shed some light on the biggest blowdown I've seen on the landbase we manage. On 9/30/86 (incredibly late for strong convection in N.Aroostook), straight line winds flattened about 600 acres in a SW-NE swath 4 miles long that ended with trees blown into the north end of Square Lake, about 15 miles SE of Ft. Kent. At its widest, the blowdown was half a mile across, and toward the center there were fully sound sugar maples 12-18" in diameter snapped off before they could uproot. By 9/30 leaf color is at/past peak there and leaf drop is 25%+, so the wind did not even have full sails to work on, except for aspen which drops its leaves later (and uproots easily because it's tall with all the foliage near the top.) My guess for windspeed max was 100 mph; might've been an underestimate, due to the character, extent, and thoroughness of tree destruction. Fortunately, having all the windthrows pointed the same way facilitated salvage, and we picked up over 3,000 cords on the west half of the area, the east half being on a private landowner for whom I don't have salvage volume. Link to comment Share on other sites More sharing options...
OceanStWx Posted September 9, 2014 Share Posted September 9, 2014 It's akin to calling a shooting during a game of Russian Roulette as a freak accident. The danger of lighting is blatantly obvious. Another favorite of mine is articles that blame car accidents during a winter storm on the road conditions. Sure the road conditions are bad, but the cause of the accident is poor driving as always. I think if you start alerting for SVR then the result is people ignoring all the alerts, they are too frequent. Is lighting even considered in issuing a SVR warning? Even if you alert for severe, could still be no warning for a storm with very prolific lighting. Lightning is never considered for SVR, other than an added call-to-action statement if it is truly a prolific lightning producer. As far as issuance goes though it only comes down to wind and hail. Other regions are doing it currently (not Eastern though) where you can "tag" a warning with hail size and wind speed. That way media and local LEOs can get the most pertinent information quickly. These are what trigger the use of sirens in some towns for something other than a tornado. The Quad Cities in IA/IL agreed that significant severe was worth using the sirens for. So anytime a warning contained 70 mph or 2 inch hail tags the sirens were used. I suspect something similar could be done with cell phones. I know since moving up here and issuing close to 75 warnings in that time, maybe 10-15% of those have included either 70 mph or 2 inch hail. I don't think we would be over-warning in that case. I think the NWS as a whole is pretty good at identifying significant severe from something less than that. We may be not be as good with identifying severe from just sub-severe though. Link to comment Share on other sites More sharing options...
TalcottWx Posted September 9, 2014 Author Share Posted September 9, 2014 Noticed, this large limbs close call with one of the buildings in my apartment complex Link to comment Share on other sites More sharing options...
ryanjn Posted September 10, 2014 Share Posted September 10, 2014 A couple pics from North Andover. I got dozens more and took a lot of notes I have to type out still. Link to comment Share on other sites More sharing options...
CT Rain Posted September 10, 2014 Share Posted September 10, 2014 While unlikely... if we can destabilize tomorrow there's quite a bit of 0-1 and 0-3km shear. Nice turning of hodographs. Most models don't show any instability of consequence but it's worth watching. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted September 10, 2014 Share Posted September 10, 2014 This is sick..Might be the best closeup I've seen..or actually in it..You have to click on the link to have video play The Weather Network @weathernetwork 2m INSANE video: Russian guy pulls out of his garage seconds before it's destroyed by a tornado: http://oak.ctx.ly/r/1oo4z pic.twitter.com/B23NX6AfZP Link to comment Share on other sites More sharing options...
ineedsnow Posted September 10, 2014 Share Posted September 10, 2014 Saw this posted in the main discussion forum yesterday but it is def awesome he must have been scared to death lol <p> This is sick..Might be the best closeup I've seen..or actually in it..You have to click on the link to have video play The Weather Network @weathernetwork 2m INSANE video: Russian guy pulls out of his garage seconds before it's destroyed by a tornado: http://oak.ctx.ly/r/1oo4z pic.twitter.com/B23NX6AfZP Link to comment Share on other sites More sharing options...
Damage In Tolland Posted September 10, 2014 Share Posted September 10, 2014 NAM looks halfway decent tomorrow evening for scattered big bangs Link to comment Share on other sites More sharing options...
Professional Lurker Posted September 11, 2014 Share Posted September 11, 2014 This is sick..Might be the best closeup I've seen..or actually in it..You have to click on the link to have video play The Weather Network @weathernetwork 2m INSANE video: Russian guy pulls out of his garage seconds before it's destroyed by a tornado: http://oak.ctx.ly/r/1oo4z pic.twitter.com/B23NX6AfZP That's nuts. Must have said to himself, "OMG, Tor!" Link to comment Share on other sites More sharing options...
TalcottWx Posted September 11, 2014 Author Share Posted September 11, 2014 Today looks abysmal, and so does any long range chances at all for storms. end of the storm season? Link to comment Share on other sites More sharing options...
Nittany88 Posted September 11, 2014 Share Posted September 11, 2014 You'd think we're bound to get at least one high shear low CAPE fine-line deal between now and November. We seem to get at least one of those per year. Link to comment Share on other sites More sharing options...
tamarack Posted September 11, 2014 Share Posted September 11, 2014 Today looks abysmal, and so does any long range chances at all for storms. end of the storm season? Might've ended here on August 14. Link to comment Share on other sites More sharing options...
ryanjn Posted September 11, 2014 Share Posted September 11, 2014 Today looks abysmal, and so does any long range chances at all for storms. end of the storm season? At least it was a good one up our way. And I agree with Nittany about a high shear event, there will probably be some storm that brings down some limbs somewhere that has 2 claps of thunder tops at some point hah. Idk why this is typing in italics but ignore that. Link to comment Share on other sites More sharing options...
Cyclone-68 Posted September 11, 2014 Share Posted September 11, 2014 Has anyone estimated an intensity for that Russian tornado? Link to comment Share on other sites More sharing options...
TalcottWx Posted September 11, 2014 Author Share Posted September 11, 2014 Has anyone estimated an intensity for that Russian tornado? Guessing under EF2 due to the fact his vehicle wasn't airborne Link to comment Share on other sites More sharing options...
CoastalWx Posted September 11, 2014 Share Posted September 11, 2014 Guessing under EF2 due to the fact his vehicle wasn't airborne An EF-O actually can flip a car. Link to comment Share on other sites More sharing options...
TalcottWx Posted September 11, 2014 Author Share Posted September 11, 2014 An EF-O actually can flip a car. Ah I had no idea I googled EF car damage tornado.. lol. Must have been a pretty weak tornado then? Link to comment Share on other sites More sharing options...
powderfreak Posted September 11, 2014 Share Posted September 11, 2014 <p> This is sick..Might be the best closeup I've seen..or actually in it..You have to click on the link to have video play The Weather Network @weathernetwork 2m INSANE video: Russian guy pulls out of his garage seconds before it's destroyed by a tornado: http://oak.ctx.ly/r/1oo4z pic.twitter.com/B23NX6AfZP That's f'ing nuts! Link to comment Share on other sites More sharing options...
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