F5Chaser

Well, that was not worth the drive. I thought the hodographs were acceptable in northwest WI despite southwest flow at the surface. I think they would have been fine had all the storms not decided to fire north of the outflow boundary. I had a feeling things would line out quickly when I encountered northwest winds on the north side of the outflow boundary between Cromwell and Kettle River on MN73. Pre-tornadic outflows usually feature an easterly component to the winds.

I waited in the Sandstone/Hinckley area for a discrete storm to develop and carry me into Wisconsin (hey, I'm used to chasing up here in the trees, so WI isn't really a problem), but that never happened, so I still have yet to make my first chase into that state. For someone who has lived within 20 miles of the border for much of his life, that's pretty amazing. I think it may never happen. It's not the trees-- it's the lack of decent structure with storms I've seen close to the Wisconsin border (closest, by the way, was late May 1994 on a tornado-warned supercell storm).

Good call by Randy Hill and anyone else who decided not to chase today.

-Bob

Wish I decided not to chase but made the best out of it I suppose.

This is an area I was hearing mentioned as a possible wall cloud near Rice, MN which was rotating but dont think I would have called it a wall cloud as it was buried under a shelf.

This was a pretty cool site of a notched area along the shelf that formed and then really started to do some strange things. On the back side there was a funnel, not very smooth but it was acting just like one. Shelves are always so strange with so much movement I dont know what to think of it to be honest.


More images xtremewx.com/July27th2010.htm

My girlfriend wanted to go chasing for the first time in years since it was close by and not a work day, or without more important things to do, like refilling the bird feeder. It was a nice surprise!

I was surprised how long the SEly winds were hanging around, so that gave me hope and the first possible justification for the SPC's outlook. We left at 3:30, and before I knew it the winds out west were quickly switching to SW or worse. We turned off at Avon to head north to where the surface winds were still mostly southerly. It was a gamble in bad chase terrain vs bad sfc winds further west.

We ended up by the couplet on the middle of the 3 tor warned storms, but there was a shelf in front of it and cold outflow as Tadd said. There was a lowing back there, but it had no movement and it was behind the shelf. At that point it was pretty early, say 5 or 5:30 PM, and we headed down Hwy 10 to St Cloud to go home. Stopped in Howard Lake for dinner at a nice little place looking over the lake, and watched the storm come in again from across the lake while the locals scurried to get home before it hit.

One thing I'm wondering about this day, is why the line of storms was so skinny. There was plenty of instability and moisture. Is it a cap, wind direction, or convergence, that kept it from becoming bows with monster shelves?

One thing I'm wondering about this day, is why the line of storms was so skinny. There was plenty of instability and moisture. Is it a cap, wind direction, or convergence, that kept it from becoming bows with monster shelves?

Great question which I also wonder about. Why did the storms not remain on the severe level? Why was there a 10minute gap between the shelf and rain?

Tony we must have been close to each other near the Avon area. Think I was maybe just a tad more to the NE. Was fun trying to outrace the shelf and rain near the St. Cloud area, man that stuff was cruising.

So it was rare that the rain was so far behind the shelf? I decided not to go out but thought I would try and get some shots of the shelf so I was watching radar waiting for it to get close to my parent's house. I decided to head out when according to radar it was almost another county over but when I started driving it was already on top of me and then it didn't rain for at least 10 minutes. I thought it was strange but I don't have much experience with the shelves so I just shrugged it off. As far as the lack of severity, I was definitely surprised that it seemed to weaken as it got closer to the metro but the weather guy on channel 4 was saying he thought there would only be heavy rain in the metro and I thought he was crazy because it seemed like there was still plenty of ample instability but he was obviously right.....

JKraft wrote:
So it was rare that the rain was so far behind the shelf?

I don't think it's rare to see the rain so far behind the shelf as this tends to happen as the gust front outruns the precip core in these instances. This is what really leads to weakening of a line of storms as what happened on Tuesday as it approached the metro. The storm outflow that created that gust front became faster than the overall storm movement, so much so that the inflow/outflow balance on the leading edge where the shelf was at was disrupted.

My short chase log for the 27th..I really didn't want to make a trip to MN so I sat here in WI watching the radar...Make along story short I needed up heading into Polk County with the mind of heading towards Luck area..However with the late start I ended up sitting in Mckinley which turned out to be a good thing. (I have pictures however for me I can't see to post pictures anymore )... Anyway I was able to stay out in front of this storm as I raced down HWY 48 back towards Cumberland.. I had time to get more pictures, so I dropped South on HWY 63 about a mile....It seemed like this storm had it out for me as the line was dropping South/Southeast... I headed East on HWY 48 got delayed at the four way stop....Got through that and headed East to the Rabbit trail... I dropped South trying to get into a better area as it seemed to be more rain to the my North/Northwest...Crossed I Highway T and got about a mile or South of T and then the storm won... I recorded a wind gust of 60.3 MPH ...There was some tress downed, however nothing blocking the rd... So I got back on HWY T and headed South... About 6 to 8 Miles Southeast of Cumberland I ran into more damage, Was able to get to HWY 8.... One mile West of the City of Barron a large tree was blocking the West bound lane.... Police and fire already there, also power line was downed... More damage was noted East of Barron, along with the village of Cameron and one mile South of Rice Lake.. I did see one tress down in the City of Rice Lake, but by this time it was getting rather dark... Headed back home where I saw some damage on my rd...I had a tree go down in my yard, along with branches all over... Wednesday I was out taken damaging pictures and talking with lots of people.... Again I do have pictures of that, but I can't get the picture thing to work for me.... Ok so this was longer then what I was going for LOL...

Nice pictures Tadd! Looks close to what I was seeing over here WI...

Well, there were tornadoes with this event after all.

Duluth NWS damage survey

The forecast idea I had was essentially correct. The forecast hodographs looked best in northwest Wisconsin. I just didn't leave until 2:15, and that put me a little late to get to the right spot, although I had maybe not forecast it to be quite that far east. The storm broke out from the outflow boundary about a county east of where I was in Hinckley/Sandstone.

A better chase strategy would have been to leave earlier and get farther east in the target area prior to initiation. Leaving from work made it a bit more difficult to commit to the better shear farther east and therefore I fudged a bit and headed for Hinckley/Sandstone, hoping something would initiate in the warm air south of the outflow boundary in extreme eastern Minnesota and then move into Wisconsin. That did not work out, so...

Just another case where it would have been better with a chase partner and a full day off from work. Had I made it to the cell, though, I probably would have had a rough time in poor road network and would have been overtaken by some pretty nasty stuff. The storm looked meaner and nastier when it started producing tornadoes, which would have been tough to see.