WX-CHASE Digest - 15 Apr 1999 to 16 Apr 1999 - Special issue (#1999-38) Date: Fri, 16 Apr 1999 23:09:07 -0500 From: Automatic digest processor Reply-To: The WX-CHASE list To: Recipients of WX-CHASE digests There are 23 messages totalling 843 lines in this issue. Topics in this special issue: 1. GOOD GRIEF!!!!!! (3) 3. more GOOD GRIEF!!!!!! (3) 9. Good Grief!!! (NC Thunderstorms & Tornados)] 10. GOOD GRIEF (NC storms of 4-15-99) (2) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ To unsubscribe from WX-CHASE send e-mail to LISTSERV@PO.UIUC.EDU with "unsub wx-chase" in the body of your message. For help with WX-CHASE see http://ralph.centerone.com/wxfaq.html or write chris@siu.edu. ---------------------------------------------------------------------- Date: Fri, 16 Apr 1999 01:45:44 -0600 From: Ralph Forsythe Subject: Re: GOOD GRIEF!!!!!! Gilbert Sebenste wrote: > 1020 PM TRENTON NC 165 MPH TSTM GUST > 04/15/99 JONES WIND EQUIPMENT SHOWED > GUSTS TO 165 MPH, BARNS, > TREES DESTROYED, ALL > HUNTING DOGS KILLS, N OF > TRENTON I've heard of strong gusts, but 165MPH?? I second that - WOW! Just curious, but what conditions would need to occur to cause something like this? All I can figure is a massively outflow-dominant storm creating one hell of a microburst, but even then this would be tornado-strength winds, just no rotation... - Ralph Forsythe ralph@centerone.com ------------------------------ Date: Fri, 16 Apr 1999 07:41:46 -0500 From: Gene E Moore Subject: Re: GOOD GRIEF!!!!!! Ralph Forsythe wrote: > Gilbert Sebenste wrote: > > 1020 PM TRENTON NC 165 MPH TSTM GUST > > 04/15/99 JONES WIND EQUIPMENT SHOWED > > GUSTS TO 165 MPH, BARNS, > > TREES DESTROYED, ALL > > HUNTING DOGS KILLS, N OF > > TRENTON > > I've heard of strong gusts, but 165MPH?? I second that - WOW! Just > curious, but what conditions would need to occur to cause something like > this? All I can figure is a massively outflow-dominant storm creating > one hell of a microburst, but even then this would be tornado-strength > winds, just no rotation... I'll bet, without seeing the radar there was rotation associated with the event on a larger scale, like a mesocyclone. I'm a little skeptical of a true wind of 165 mph; weather equipment can do strange things to cause inaccuracies. Also, many wind instruments are not rated to accurately measure such speeds. Assuming it's true, generally the only way something of this magnitude can occur is a mesocyclone generated down burst. You have probably seen some of Fujita's work depicting surveys of mesocyclone damage he published years ago. For those not familiar with the subject: down bursts (or microbursts) may occur on the backside of the mesocyclone where the cold down draft winds are entrained into the circulation and concentrated into a narrow channel. This channel of wind sweeps around the the circulation spreading out to destroy property. Occasionally, strong mesocyclones produce these events over tens of miles without forming a classic tornado funnel. I haven't read anything specific on this, but it seems to occur with stronger pulsing supercells. It drives the damage survey people crazy and usually takes an aircraft's overview to resolve. These reoccurring down burst patterns are difficult to see in the plains, but show up well in forested regions. I was chasing during one such incident that mowed down miles of trees "after" the tornado dissipated. This damage was all straight line, divergent and well within what an F2/3 tornado would have done. I have read discussions concerning the type of warning that should be issued for such extreme events. Some believe only a tornado warning is appropriate since severe warnings are sometimes ignored or not taken seriously. As for the extreme range on pure outflow gust fronts, I have seen 120 mph documented, but not much over that figure. Perhaps others can contribute here. Gene Moore ------------------------------ Date: Fri, 16 Apr 1999 07:58:56 -0500 From: Gene E Moore Subject: Re: more GOOD GRIEF!!!!!! Gilbert Sebenste wrote: > >From the "WOW!" department: > > WWUS30 KMHX 160238 > LSRMHX > > PRELIMINARY LOCAL STORM REPORT > NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC > 1035 PM EDT THU APR 15 1999 > > TIME(EDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS... > ....COUNTY LOCATION.... > > 1020 PM TRENTON NC 165 MPH TSTM GUST > 04/15/99 JONES WIND EQUIPMENT SHOWED > GUSTS TO 165 MPH, BARNS, > TREES DESTROYED, ALL > HUNTING DOGS KILLS, N OF > TRENTON Upon learning more about this event, there was a strong mesocyclone associated with the storm. The measurement may have occurred near a tornado. SPC may post some radar images on their site. WeatherTap allows reposting of their images when credit is given. Anyone collecting radar during this time period? I understand the images are spectacular. gm ------------------------------------------- Date: Fri, 16 Apr 1999 10:38:38 EDT From: Richard Horodner Subject: Re: GOOD GRIEF!!!!!! > Gilbert Sebenste wrote: > > 1020 PM TRENTON NC 165 MPH TSTM GUST > > 04/15/99 JONES WIND EQUIPMENT SHOWED > > GUSTS TO 165 MPH, BARNS, > > TREES DESTROYED, ALL > > HUNTING DOGS KILLS, N OF > > TRENTON This might very well be accurate; BUT because it is so unusual, validity of the instrument is a question. Is the anemometor in question the "hot wire" type that is often used these days at military installations: and has proven to give erroneous readings in heavy rain situations? The type whose winds during tropical cyclones at Guam, Biloxi, and Ft. Walton Beach in recent years (200+, 172, and 145 mph) were all shown to be bogus. OR Was one of the hunting dogs a greyhound? Did he get caught up in one of the cups? ------------------------------ Date: Fri, 16 Apr 1999 12:57:38 -0400 From: Steve Sponsler Subject: Re: more GOOD GRIEF!!!!!! Gene E Moore wrote: > > Gilbert Sebenste wrote: > > > >From the "WOW!" department: > > > > WWUS30 KMHX 160238 > > LSRMHX > > > > PRELIMINARY LOCAL STORM REPORT > > NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC > > 1035 PM EDT THU APR 15 1999 > > > > TIME(EDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS... > > ....COUNTY LOCATION.... > > > > 1020 PM TRENTON NC 165 MPH TSTM GUST > > 04/15/99 JONES WIND EQUIPMENT SHOWED > > GUSTS TO 165 MPH, BARNS, > > TREES DESTROYED, ALL > > HUNTING DOGS KILLS, N OF > > TRENTON > > Upon learning more about this event, there was a strong mesocyclone associated with > the storm. The measurement may have occurred near a tornado. > > SPC may post some radar images on their site. > > WeatherTap allows reposting of their images when credit is given. Anyone > collecting radar during this time period? I understand the images are spectacular. > > gm I'm wondering..what is the likelihood that if the aneometer was not in error, that a tornado could have passed directly over it? Has there been an aerial survey of the area (or potential damage path) to determine the extent of the damage here? This LSR was posted at night...so clearly any true ascertainment of damage extent AND cause could not have been made at the time it was put out. I gather by the end of today we'll know more... Steve ------------------------------ Date: Fri, 16 Apr 1999 13:25:32 -0400 From: Greg Johnson Subject: Re: Anyone chase in NC yesterday? Yep, I tried to. But was not able to see anything. However I heard lots of reports on Skywarn. At 09:35 AM 4/16/99 -0400, you wrote: >Anyone chase yesterday in NC? I did, but gave up on the southern >Peidmont/Sandhills once the "action" started in northern NC. Live >and learn... > KG4AWG Greg Johnson Central Carolina Skywarn Spotter http://www.qsl.net/kg4awg http://www.centralcarolinaskywarn.net ICQ:8912046 AIM:kg4awg ------ "I do not know whether I was then a man dreaming I was a dragon, or whether I am now a dragon dreaming I am a man." -- Chang-tzu(adapted) ------------------------------ Date: Fri, 16 Apr 1999 12:58:27 -0500 From: Mike Umscheid Subject: Re: more GOOD GRIEF!!!!!! At 07:58 AM 4/16/99 -0500, Gene E Moore wrote: >Upon learning more about this event, there was a strong mesocyclone associated with >the storm. The measurement may have occurred near a tornado. > >SPC may post some radar images on their site. > >WeatherTap allows reposting of their images when credit is given. Anyone >collecting radar during this time period? I understand the images are spectacular. > >gm I was watching TWC last night while this event was going on. Kudos to TWC, btw, as they were on top of this situation, showing 88D reflectivity and velocity close-up images. I was very impressed with this supercell. It had at least +50/-50 GTG couplet as it went through the town of Trenton. You could have fooled me if there wasn't a tornado in that storm. The reflectivity on that storm was also incredible, as it resembled a tropical cyclone somewhat, with very mesoscale "banding" going on. Quite interesting indeed. Too bad I didn't save any images, this was quite an impressive meso. Also, at the time that LSR came out, the TWC meteorologist (forgot which one), said something to the extent "A 165mph wind gust was reported by wind equipment at the town of Trenton. The tornado apparently went over the wind equipment, and if this reading is accurate, this would be an F3 tornado..." Mike U =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Mike Umscheid <> freshman, Johnson Co. Comm. College mscheid@kc.net <> Overland Park, KS <> "Meso" Chaser 'Under the Meso!' ~\_/~ http://www.kc.net/~mscheid/mesopage =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ------------------------------ Date: Fri, 16 Apr 1999 14:02:55 -0400 From: Jesse Ferrell Subject: Re: Good Grief!!! (NC Thunderstorms & Tornados)] Whoops! Sent to wx-talk instead of wx-chase. Well here it is: -------- Original Message -------- Subject: Re: Good Grief!!! (NC Thunderstorms & Tornados) Date: Fri, 16 Apr 1999 10:02:04 -0400 From: Jesse Ferrell - CASI Organization: Central Atlantic Storm Investigators To: WX-TALK General weather discussions and talk References: <199904160505.AAA45362@postoffice.cso.uiuc.edu> Yes it was rough down there in NC last night! I have put up some additional information including METARs from the area, which feature a 75mph thunderstorm gust and sighting of Tornado, at http://www.weatherwatchers.org/1999/0415/ P.S. - I can't find this Jones County station in the NWS, FAA, or AWS databases, it must have been a private one, does anyone know? I'd love to see the raw data. Automatic digest processor wrote: > From: Gilbert Sebenste > Subject: GOOD GRIEF!!!!!! > > >From the "WOW!" department: > NC 165 MPH TSTM GUST -- ============================================================== Jesse Ferrell - Meteorologist/Web Dev. - j@weatherwatchers.org Central Atlantic Storm Investigators - www.weatherwatchers.org ------------------------------ Date: Sat, 17 Apr 1999 15:19:43 -0400 From: Daniel Dix Subject: Re: GOOD GRIEF (NC storms of 4-15-99) > Date: Thu, 15 Apr 1999 23:13:21 -0500 > From: Gilbert Sebenste > Subject: GOOD GRIEF!!!!!! > >>From the "WOW!" department: > > WWUS30 KMHX 160238 > LSRMHX > > PRELIMINARY LOCAL STORM REPORT > NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC > 1035 PM EDT THU APR 15 1999 > > TIME(EDT) .....CITY LOCATION..... STATE ...EVENT/REMARKS... > ....COUNTY LOCATION.... > > 1020 PM TRENTON NC 165 MPH TSTM GUST > 04/15/99 JONES WIND EQUIPMENT SHOWED > GUSTS TO 165 MPH, BARNS, > TREES DESTROYED, ALL > HUNTING DOGS KILLS, N OF > TRENTON > > It was bad enough that it was tax day, but it looks like Ma nature did an > audit on Trenton! :-( The radar data is incredible. Just before the supercell reached Trenton/New Bern, NC it had a starfish or octopus look to it. Bizarre! It was incredible to see! I have not looked at news, net, etc today but can imagine there will be quite a mess in eastern NC to wake up to. DD.. -- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Daniel Dix Meteorologist/Geographer 'Skol Vikings!!! Super Bowl 34 in 2000!!! Atlanta, GA ddix@bellsouth.net ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Subject: WX-CHASE Digest - 16 Apr 1999 to 17 Apr 1999 (#1999-39) Date: Sun, 18 Apr 1999 00:00:11 -0500 From: Automatic digest processor Reply-To: The WX-CHASE list To: Recipients of WX-CHASE digests There are 9 messages totalling 262 lines in this issue. Topics of the day: 2. Wind Gauge 165mph reading 3. NC Radar images 7. Good Grief / NC 165mph Gust 8. North Carolina "Tornadocane" +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ To unsubscribe from WX-CHASE send e-mail to LISTSERV@PO.UIUC.EDU with "unsub wx-chase" in the body of your message. For help with WX-CHASE see http://ralph.centerone.com/wxfaq.html or write chris@siu.edu. ---------------------------------------------------------------------- Date: Sat, 17 Apr 1999 04:57:15 -0500 From: Gregg Schulz Subject: Re: WX-CHASE Digest - 15 Apr 1999 to 16 Apr 1999 - Special issue (#1999-38) The only place that I've ever heard getting that strong of winds is either in a hurricane, Antarctica, or that one weather station up on a mountain in the NE. Can't think of which one it is though by name. Gregg nbfd131@execpc.com ------------------------------ Date: Sat, 17 Apr 1999 05:00:07 -0500 From: Gregg Schulz Subject: Wind Gauge 165mph reading I am sure that the wind gauge in NC is probably fairly close as they also take Hurricane readings from that area I'm sure. I also agree that it was probably due to a microburst or macroburst. Would make sense. I'm sure we'll hear more about it in the near future as the NWS gets more data. Gregg nbfd131@execpc.com ------------------------------ Date: Sat, 17 Apr 1999 09:42:45 -0400 From: David Lewison Subject: NC Radar images > WeatherTap allows reposting of their images when credit is given. Anyone collecting radar during this time >period? I understand the images are spectacular. >gm I was following that massive storm on Thursday night via the internet. I captured a NEXRAD image from Morehead City from Intellicast. I don't have a WeatherTAP account, but this still shows the storm clearly. I also have a video still from TWC's velocity data. (sorry for the white circle...I was posting it for others to see). http://www.nyshrm.org/dave/raleigh.gif http://www.nyshrm.org/dave/velocity.jpg Now for a question...with the spiraling band effect, is it safe to say that if there was a tornado, it was rain-wrapped? Also, from basic Skywarn training, I was told that a storm usually pulls its inflow from the SE part of the storm, and if this inflow is cutoff by rain (occluded?), the storm begins to die. Since this storm is almost completely surrounded by heavy reflectivity, how did it manage to stay strong for so long? Thanks, ----Dave-----> -- Design/Manufacturing Masters Student Dept. of Mechanical Engineering, RPI Troy, NY 12180 (518) 276-5880 http://www.rpi.edu/~lewisd2 http://www.nyshrm.org/dave ------------------------------ Date: Sat, 17 Apr 1999 18:26:08 GMT From: Jesse Ferrell - CASI Subject: Re: Good Grief / NC 165mph Gust > hotwire anemometer? I have heard (3rd party) that it was a Davis WMII at an amateur radio operator's house. j@weatherwatchers.org CASI www.weatherwatchers.org ------------------------------ Date: Sat, 17 Apr 1999 17:57:43 -0500 From: Roger Edwards Subject: North Carolina "Tornadocane" Some images and info on the event are now online: http://www.spc.noaa.gov/coolimg ...including a javascript reflectivity loop. Enjoy... [Further changes possible as updated info and/or additional interpretations roll in.] ----------------------------------- *** No disclaimer necessary; this is my personal account! *** "A Meatwagon at rest tends ===== Roger Edwards ===== to remain at rest." ( ) Forecaster - storm intercept partner, 1996 former NHC Forecaster :::::::::: http://www.wildstar.net/~tornado :::::::::: "I FEAST ON THE SMORGASBORD OF ATMOSPHERIC VIOLENCE." ------------------------------ End of WX-CHASE Digest - 16 Apr 1999 to 17 Apr 1999 (#1999-39) ************************************************************** End of WX-CHASE Digest - 16 Apr 1999 to 17 Apr 1999 (#1999-39) **************************************************************