Bill Tabor
EF5
Note: This post is from a duplicate I posted to Wx-Chase in reply to comments from Dave Lewison which was originally a topic about Threatnet versus other NWS type radar presentation. However I think it is a good case situational study and I wanted to discuss it on StormTrack anyway. It follows:
Dave Lewision said:
> What I'd like to point out is the lack of a useful reflectivity scale. The Tnet shows all purple
> (>55dBz). In our position, we were stopped by downed power poles to the south and the only escape
> was back to the north. But the Tnet was showing this massive wall of purple back that way, so we
> didn't go. Now look at the NWS presentation...the NASTIEST part of the core was actually to our
> West about to nail us. Going north would probably have been a decent escape route with somewhat
> smaller hail.
Nope. It was too late after the initial torn began roping, and when the next multi-vortex began the
core was on top of us. I hung around too long considering following on the east road option when the
RFD / inflow jet to developing tornado (or whatever it was) started up from the west bringing the
large hail with it. With winds roaring as inflow to that larger wallcloud to the east I wasn't
convinced I wasn't possibly under part of a newly developing very large tornado - as sometimes they
can get up to 1 or 2 miles in rare circumstances. (Recall our earlier threads about Hallam). Already
cut off to the south and wallcloud / developing tornado to the east I chose the north option and the
deep core to keep me safe. I knew I would take a pounding (and I did) but figured I wanted out from
under any possible rotation at that point and into the definite downdraft region. Note that as I was
doing this Threatnet was showing about 6 shear markers directly over my area with winds showing up
to 138 - 142 mph. I think in this case most likely once again there was a delay and the area of
shear shown per Tnet and inflow was actually to my east as I made my way north.
Reflecting on this after the fact I think most of us made the wrong choices that day for navigating
this storm's hazards. I think there were two reasonably good choices we didn't make because we were
all directly in front of the eastward moving tornado initially (but north of the east road option)
and we all just stayed around in fascination, and watched it cross the road to our south. Normally
I would choose to be just south of the crossing tornado (near or in the town of South Plains), or I
would stay ahead of it having already gotten on my east road option and kept my distance as the
tornado came out after me.
Instead when the tornado (large white elephant trunk to our west) began developing and finally
developed I could see some high speed wind / dust / rain bands headed across the plowed fields due
southeast of the tornado. It looked like these were headed directly for the town of South Plains.
Last minute I realized my mistake and tried to make that option only to be cut off by the large
tornado looming directly in my windshield probably only a few hundred yards away before I retreated
from my southward folly. I couldn't beat the tornado out. Did anyone see this high wind event
travelling out from the tornadic area? I assume this was RFD related, and might have been
responsible for bringing the power poles down on the highway that Scott McPartland and Dave
mentioned. Alternatively the passage of the torn might have brought them down. These straight line
winds looked troubling and potentially hazardous but possibly doable had I chose that option sooner.
Any opinions on this?
A lot (if not most) chasers chose to follow east on the eastbound road after the stovepipe
diminished. However I got out of my vehicle and looked east. I saw a new even larger wallcloud
stretching north and south directly across the eastbound road. So, chasers were driving directly
under an active, tornado producing wallcloud. I called out on the radio to chasers warning of that
action to no avail. Of course we all know it didn't take long to produce again when it did the
multi-vortex torn; however by then I was more concerned with the giant hail I was encountering. I
really couldn't believe everyone was driving under the wallcloud and whereas I wasn't pleased with
my position or choice there could have been very real consequences had it produced a large tornado
while people were driving under it. The MESO team had the new tornado develop just off the eastbound
road - and not very far away, perhaps only hundreds of feet from accounts I heard, but still was
unable to avoid the hail onslaught.
I think it would have been ok though had we been on the east road earlier when the first main
tornado was initially created and before it came out. Of course it came out pretty quick and it
would take some fast road work to stay ahead of it, but I currently feel this was the BEST option
for seeing the tornadoes, keeping up with new development, and staying relatively safe from the hail
and tornadoes.
Additionally, in retrospect, I would have been better off most likely had I just stopped and turned
the back of the vehicle toward the westerly hail jet and took the pounding from the rear of my Tahoe
which is a fairly long and sturdy structure. My reasoning for not doing this was I wanted to be
further into the core, away from the inflow region, and hopefully find the smaller hail there.
(Unfortunately you have to drive quite a ways (apparently it was miles) to get out of the giant
hail, and the forward momentum of my vehicle made the westerly hail hit my vehicle in the main
windshield from the north side).
It was a wild and crazy chase, and hopefully the dashcam caught some good action including my bid
for getting south of the tornado which was a bit dramatic.
Some memories / pics of my encounter here:
http://www.tornadoxtreme.com/2005_Chases/M...ay_12th_05.html
For those of you out this day, and even those of you who weren't, what are your opinions on the road
options and storm attributes / decisions. Were you close but avoided the hail? What choice would /
did you make?
Dave Lewision said:
> What I'd like to point out is the lack of a useful reflectivity scale. The Tnet shows all purple
> (>55dBz). In our position, we were stopped by downed power poles to the south and the only escape
> was back to the north. But the Tnet was showing this massive wall of purple back that way, so we
> didn't go. Now look at the NWS presentation...the NASTIEST part of the core was actually to our
> West about to nail us. Going north would probably have been a decent escape route with somewhat
> smaller hail.
Nope. It was too late after the initial torn began roping, and when the next multi-vortex began the
core was on top of us. I hung around too long considering following on the east road option when the
RFD / inflow jet to developing tornado (or whatever it was) started up from the west bringing the
large hail with it. With winds roaring as inflow to that larger wallcloud to the east I wasn't
convinced I wasn't possibly under part of a newly developing very large tornado - as sometimes they
can get up to 1 or 2 miles in rare circumstances. (Recall our earlier threads about Hallam). Already
cut off to the south and wallcloud / developing tornado to the east I chose the north option and the
deep core to keep me safe. I knew I would take a pounding (and I did) but figured I wanted out from
under any possible rotation at that point and into the definite downdraft region. Note that as I was
doing this Threatnet was showing about 6 shear markers directly over my area with winds showing up
to 138 - 142 mph. I think in this case most likely once again there was a delay and the area of
shear shown per Tnet and inflow was actually to my east as I made my way north.
Reflecting on this after the fact I think most of us made the wrong choices that day for navigating
this storm's hazards. I think there were two reasonably good choices we didn't make because we were
all directly in front of the eastward moving tornado initially (but north of the east road option)
and we all just stayed around in fascination, and watched it cross the road to our south. Normally
I would choose to be just south of the crossing tornado (near or in the town of South Plains), or I
would stay ahead of it having already gotten on my east road option and kept my distance as the
tornado came out after me.
Instead when the tornado (large white elephant trunk to our west) began developing and finally
developed I could see some high speed wind / dust / rain bands headed across the plowed fields due
southeast of the tornado. It looked like these were headed directly for the town of South Plains.
Last minute I realized my mistake and tried to make that option only to be cut off by the large
tornado looming directly in my windshield probably only a few hundred yards away before I retreated
from my southward folly. I couldn't beat the tornado out. Did anyone see this high wind event
travelling out from the tornadic area? I assume this was RFD related, and might have been
responsible for bringing the power poles down on the highway that Scott McPartland and Dave
mentioned. Alternatively the passage of the torn might have brought them down. These straight line
winds looked troubling and potentially hazardous but possibly doable had I chose that option sooner.
Any opinions on this?
A lot (if not most) chasers chose to follow east on the eastbound road after the stovepipe
diminished. However I got out of my vehicle and looked east. I saw a new even larger wallcloud
stretching north and south directly across the eastbound road. So, chasers were driving directly
under an active, tornado producing wallcloud. I called out on the radio to chasers warning of that
action to no avail. Of course we all know it didn't take long to produce again when it did the
multi-vortex torn; however by then I was more concerned with the giant hail I was encountering. I
really couldn't believe everyone was driving under the wallcloud and whereas I wasn't pleased with
my position or choice there could have been very real consequences had it produced a large tornado
while people were driving under it. The MESO team had the new tornado develop just off the eastbound
road - and not very far away, perhaps only hundreds of feet from accounts I heard, but still was
unable to avoid the hail onslaught.
I think it would have been ok though had we been on the east road earlier when the first main
tornado was initially created and before it came out. Of course it came out pretty quick and it
would take some fast road work to stay ahead of it, but I currently feel this was the BEST option
for seeing the tornadoes, keeping up with new development, and staying relatively safe from the hail
and tornadoes.
Additionally, in retrospect, I would have been better off most likely had I just stopped and turned
the back of the vehicle toward the westerly hail jet and took the pounding from the rear of my Tahoe
which is a fairly long and sturdy structure. My reasoning for not doing this was I wanted to be
further into the core, away from the inflow region, and hopefully find the smaller hail there.
(Unfortunately you have to drive quite a ways (apparently it was miles) to get out of the giant
hail, and the forward momentum of my vehicle made the westerly hail hit my vehicle in the main
windshield from the north side).
It was a wild and crazy chase, and hopefully the dashcam caught some good action including my bid
for getting south of the tornado which was a bit dramatic.
Some memories / pics of my encounter here:
http://www.tornadoxtreme.com/2005_Chases/M...ay_12th_05.html
For those of you out this day, and even those of you who weren't, what are your opinions on the road
options and storm attributes / decisions. Were you close but avoided the hail? What choice would /
did you make?