Strongest Michigan Tornado in Ten Years

[Mike Kovalchick]

See http://www.crh.noaa.gov/crnews/display_story.php?wfo=grr&storyid=9889&source=0

Shows some very impressive damage photos, radar grabs, etc.

This link shows the only pic of the tornado(very hard to see) that I can find:

http://www.crh.noaa.gov/crnews/display_story.php?wfo=grr&storyid=9875&source=0

Here's another link on all the other tornadoes that occurred on the 24th in Michigan

http://www.crh.noaa.gov/crnews/display_story.php?wfo=dtx&storyid=9886&source=0

 

[Mike Kovalchick]

With most Michigan tornado outbreaks, they seem to develop with little warning. How well did the experts do on this one?

The SPC had a 2% Tornado risk for Michigan for Day 1. They issued a Severe Thunderstorm Watch at 4:05 PM EDT and the first tornado occurred at 4:25 PM. No Mesoscale discussions for the zone impacted were issued until near the end of the event at 6:50 PM. At 3:45 PM EDT, a Mesoscale Discussion was issued for the region just to the South of the area as being the primary threat area despite explosive thunderstorm development occurring at this time near Grand Rapids.

The 2 local NWS offices did a very good job with their warnings..I believe tornado warnings preceeded all the tornadoes.

The local Channel 10 news meterologist did a good job despite a few mistakes. He initially left the impression that the storm was headed for the NW suburbs of Lansing when instead it crossed through South Lansing doing extensive damage..and failed to keep reminding the viewing audience that radar/velocity images are delayed...and this is very important when the storms are moving rapidly as in this situation. (shouldn't they place a time stamp on the images?) He also referred to an obvious Supercell..as a multicell pulse storm. I did like how they relayed NWS warnings even before they reached my weather radio.

Finally, the local tornado sirens were properly activated although I believe in many cases they turned on belatedly...or at least well after a tornado warning already been issued. In the case of my home town of Haslett, I am quite sure the sirens were not activated for at least several minutes after the NWS tornado warning that specifically listed Haslett in the warning message.

 

[Bob Hartig]

These storm puzzle me. What made them go tornadic--or, more accurately, when did those conditions pop up? I'm not surprised that the mesoscale discussion was for parts south of the action--that's where RUC located the better EHIs. The winds for this system promised to be unidirectional, pretty much straight westerly at different levels.

I got completely snookered by my own expectations--or lack thereof--and sat on my butt in the Hastings, MI, library, watching GR3 as the supercell that hit Pottersville and Lansing matured pretty much right overhead and dropped a ton of rain. No big deal, right? Even when I watched the cell develop two suspicious appendages on its southern flank, I took only casual interest. Just an anomally, that's all. Then a TVS popped up a little way to my east. That got my attention, but I still figured it would be gone in a sweep or two; I just didn't think there was enough helicity to sustain it. Still, at that point, I mounted a chase that was doomed from the start. I never did catch up with the storms. But I was amazed to see the rotation going on in them. I watched one particularly impressive area approaching Flint; another weaker area was several miles directly in front of me as I headed east down I-96 toward Lansing. I finally gave up the chase on a dirt road just east of a little burg called Cohoctah, a few miles west of Holly.

I'm curious what the mets have to say about what happened with this system. What did I miss in interpreting the winds? If the surface winds backed, I can see how that could provide the brief spinups typical of this kind of system in Michigan, but these storms had sustained rotation, not to mention --my gosh!--EF-3 damage there near Pottersville.

 

[Robert Dewey]

The SFC winds backed... the RUC correctly predicted this 6 hours in advance. SPC mesoanalysis indicated 0-3km helicities up around 200-300m2/s2, and with the building instability and broken nature of the squall line, I seen a small TOR threat. As usual, the comm-head of a bow echo is always suspect, but there were many breaks and LEWPs evident, which is also a focal point for strong rotation.

Really, this shouldn't have caught seasoned mets off guard. The clues were subtle, but they were there. In the NOW thread, I stated that I thought there was a chance at some brief spin-ups... with the exception of the EF3, that's pretty much what happened.

 

[rdale]

There was an EF2 in Livingston Co, and even the EF1 in Lansing is a bit more than a "brief spinup" ;> I have a few more pics I'll post as I put a big batch online. The initial supercell was not a comma head or break in the line, it was an individual supercell which I don't think anyone would have imagined. But the Eaton warning was in plenty of time so no biggie.

There was not a Tornado Warning in effect for Ingham Co when the Lansing tornado hit, but we were covering it as a tornado regardless.

Including one of my chasevan with the tornado in the background.

As in behind me but I didn't know it.

 

[rdale]

http://skywatch.org/PottervilleTor.jpg

Potential captions:

"Only StormTracker 6's Chase Van was on the scene of the tornado"

Or...

"Stupid chaser doesn't realize the tornado is in his rearview mirror and misses it"

"Is Rob scared? Why is he going away from the tornado?"

 

[Robert Dewey]

There was an EF2 in Livingston Co, and even the EF1 in Lansing is a bit more than a "brief spinup" ;> I have a few more pics I'll post as I put a big batch online.

I guess that's where my opinion differs. A tornado lasting 5-10 minutes and hitting a house or two doing EF1 (or even EF2) damage isn't what I would call a long-lived event.

My point of the post was that there was no reason that tornadoes couldn't have been predicted. METER from LAN eastward had SE winds and growing low level helicity... combined with the rather low LCLs.

Sure I may have been wrong about the tornadoes being "spin-ups", but at least it was better than calling for no TORs

The initial supercell was not a comma head or break in the line, it was an individual supercell which I don't think anyone would have imagined. But the Eaton warning was in plenty of time so no biggie.

Never said anything about the initial supercell being a comma head. However, I'm still arguing that the initial supercell was NOT an "individual" (if anything, we can agree that it was embedded within the linear structure):

 

[rdale]

It was on the ground for 10 miles and did EF3 damage - I don't think many opinions will call that a spinup ;>

It was by the time you snapped that picture, when it formed near Hastings it was individual. I had a hard time figuring it out, I saw the hook welldefined but I "figured" it had to have come from some sort of cell merger. Looping it shows that was not the case, it was all by itself. No sooner had I sent a message about it on the IEMChat page and decided to head out.

 

[Robert Dewey]

Hence my statement:

Sure I may have been wrong about the tornadoes being "spin-ups"

But... I still stand by my brief argument

Either way, it was a good Michigan event, but a difficult one to chase. Finding stuff embedded in lines is quite difficult... not like the isolated stuff you see on the Plains. For that, I have to say good catch Rob... I sure as hell wouldn't have been able to see anything

 

[Mike Kovalchick]

Nice radar loop of the line of storms with embedded sups:

http://www.crh.noaa.gov/images/dtx/events/RefLoop.gif

It is interesting to watch how the Supercells interact with the rest of the line.

One obvious feature in this case was an apparant inflow jet impinging on the back of the line where it was tornadic. This feature was there from West of Lansing all the way until the line swept past the Detroit area.

 

[Tony Lyza]

I guess that's where my opinion differs. A tornado lasting 5-10 minutes and hitting a house or two doing EF1 (or even EF2) damage isn't what I would call a long-lived event.

My point of the post was that there was no reason that tornadoes couldn't have been predicted. METER from LAN eastward had SE winds and growing low level helicity... combined with the rather low LCLs.

Sure I may have been wrong about the tornadoes being "spin-ups", but at least it was better than calling for no TORs

Never said anything about the initial supercell being a comma head. However, I'm still arguing that the initial supercell was NOT an "individual" (if anything, we can agree that it was embedded within the linear structure):

The Fenton upper-EF2 had a path length of 26mi.

 

[Robert Dewey]

I stand corrected on the path length.