05/09/04 NOW: MI, WI, MN, NE, SD

Larry J. Kosch

Starting a NOW thread as a severe thunderstorm watch box has been set up over Michigan. A severe t-storm warning has been issued for Cass County in Michigan. This is well out of the Moderate Risk area that SPC has put out for today. Post discussion of storms in Michigan and Upper Midwest. This thread will be changed to include specific states as the need arises. 8) LJK.
Addium to MI storm situation

This is a addium to the MI storm situation. There are two storm clusters in MI. They are in the southern and northern part of the state. However we should watch the storm line coming over Lake Michigan. It streches from Milwaukee WI down to Chicago IL and is moving E-NE.

Also storm warnings has been posted for WI and MN. Will Update heading of this thread to indicate warned areas. 8) LJK.
That's quite a healthy looking supercell in west-central MN! The vis satellite of that thing looks pretty impressive too... While it seems to be moving along the warm front, winds ahead of it are pretty much SW, making low-level shear prettty weak. Additionally, t-td depressions are 20-35 degrees, making LCLs too high for any naders. If this thing can modify it's environment a bit more or it can moisten up a bit, drop those LCLs, could have a better chance at tornadoing...
That is quite a monster riding the boundary in central MN. The anvil structure almost looks like a mini-MCS by the circular shape. You can tell the upper level winds aren't that fast but that thing definitely is exploding from that juicy CAPE. There's a little mid-level rotation from velocity images, but the storm isn't close to any immediate radar sites so the base velocity looks weak, and extremely inflow dominant at the moment, meaning this thing is getting stronger. I wouldn't be surprised to see softballs with that mother pretty soon. Pretty cool satellite image from the dissapated storm now over Minneapolis. The gusted out storm developed some cyclonic rotation kinda like the outer bands of a hurricane. I hope someone is on that immense storm because I bet a picture would be breathtaking. Now we just need to see a nice hook and a better defined inflow notch.
Torn Warn in MN

Tornado warning posted in MN. That's connected with that supercell moving towards Minneapolis MN. Here's the warning text:

331 PM CDT SUN MAY 9 2004




I don't really see any of the classic hook signatures on the NWS radar. But there's plenty of stuff going on the back side of that monster. 8) LJK.
It's taking it's sweet time coming across the lake here in Michigan. There are a few cells just making into my neck of the woods. Reports downstate of hail and some minor rotation given to GRRNWS.

Time to venture out and see what I can see :wink:

We're waiting at the intersection of I-90 and I-29, hoping for some backed surface flow as the cold front approaches from the northwest. Right now looking at elevated cu and sfc readings of about 89/60.
That central MN is kind of puzzling. The storm is in an environment of 25-40 degree t-td depressions, and SPC mesoanalysis shows low-level shear is unimpressive or perhaps at least weak (strengthening, but still unimpressive). Those huge t-td depressions are making the LCLs sky-high. I guess this is another reminder of how all bets are off when a storm is on a boundary...
I haven't seen a non-law-enforcement tornado report yet... Given a supercell on radar and the sheriff calling in a funnel - you'll get a TOR every time. I'd wait til the survey comes in before getting too puzzled ;>

Nothing of excitement on the MI storms - I hit a few of them with heavy rain and some peasized hail and 30mph winds.

- Rob
I'm near Amos' position - on I-29 south of Sioux Falls. There are some CU here with a few updrafts trying to go up - but nothing that looks overly promising yet - - - 89/63 here -
Looks to me like the cap is on the verge of breaking down here ... have a very nice looking updraft now straight east of Yankton - very healthy -
The cap has compromised here ... I'm going to go ahead and say that we have initiation ... finally ... my coordinates are 42 degrees 47 minutes x 47.22 ... due east of Yankton ... north of Sioux City about 30 miles- you won't hear from me much anymore as I'll be going visual now ... feel free to call if anyone needs - 816-351-1404
Yeah I think that area is going to explode now and then race south down I-29. Have fun with the river...lol. Will likely head north soon.
Posted a picture of what the storm looked like in Silver Lake MN this afternoon.While trying to get to the business end of the storm I was continuously overrun with dusty outlow. If someone navigated to see a tornado, my hats are off to you. I would have to say that the storm environment looked pretty ominous.Not surprised by some of the tornado reports with the whirling dust plumes on the edge of the storm. Decided not to "Go Metro" and called it off due to major metro area. Another fun day of chasing .
Jerry Funfsinn
Here's the decision guys like Amos, Mike. P., and others have to make.....

Does that cell near Vermillion SD stay on the Iowa side of the MO River, or the NE side?? The bad thing about this area is that you have 3 bridges where you can cross the river, but south of Sioux City, you have to go clear to Blair, NE. Pick the wrong side, and you're stuck with it for 70 miles. Ugh... I'm sure Mike Hollingshead has had this fun little diliemma several times. ;)

This cell looks like it's definitely the most chaseable of the bunch, and it should have free reign before that line back to the west gets a hold of it.
My guess would be that the best viewpoint of this particular cell would be on the Nebraska side of the MO River. Mike H. was right.....this bad boy is coming right down the river.
The tornado warning storm way up in northeast Nebraska is not moving and even back building to the west. With only 15 to 25 knots of mid level winds the mid level storm relative winds are 20 to 30kts.

I love chasing these storms, hardly moving beasts! Hope someone is on it, Mike P?? Send pics.
That is the sweetest radar animation, Mike G. - - wow - I love going back through and reading this play-by-play after the fact. The interesting thing about that animation ... the core of that storm was sitting dead center over the top of a local highway off of I-29 ... since a person had to go a ways west to catch up with the inflow, that meant that the ONLY way out was back through the core ... what a nightmare ride. Was trying to carry on a conversation with Kiesling and drive through the most torrential rain/hail ever ... was locked in 4x4 the whole time - still scary ... thanks for posting that.