East Central Wisconsin Storms 6-11-01

[WisconsinF5]

Before I go into my story and observations on the storms that hit East-Central Wisconsin on 6-11-01, I thought I’d post the official NWS Green Bay write up on the issue. I’d like to also point out that the official “high wind gust” reported in Oshkosh, WI was only about 74mph. After you see the pictures I will be posting you may question that figure. It is common for us to get severe thunderstorms here, complete with bow echoes and supercells. What made this one stand out was the long duration of the event (it started about 8:45pm, after the main storm passed we were treated to secondary training cells all night long. It finally gave up around sunrise) and the “bookend vortex” that caused the heavy damage. Some locals have taken to calling this incident the “Oshkosh Hurricane”.
See these two links for radar images of this storm as it hit the area; Oshkosh is located in Winnebago County, which is the nearly square one in the center. Oshkosh is near the southeast corner of the county.
http://home.new.rr.com/awfrailroadco/stormstuff/br_0219.jpg
http://home.new.rr.com/awfrailroadco/stormstuff/br_0234.jpg

-------------------From NWS-------------------
During the late evening of June 11, 2001, a large thunderstorm complex (which included a bow echo and subsequent "bookend vortex") moved across central and east-central Wisconsin. Winds exceeded 70 mph across the area, resulting in thousands of downed trees and damage to homes and businesses. What made the storm particularly significant was the sustained strong winds near the bookend vortex, causing more damage than typically experienced with a single severe wind gust. In Oshkosh, winds of 45 to 70+ mph were recorded from 919 pm until 1005 pm, veering from west to north during that span.
Warnings were issued, on average, 20 minutes before the storm hit the area. Forecasts issued by the NWS Green Bay office highlighted the risk for damaging winds as early as 4 a.m. that morning.
Meteorological Overview
The initial thunderstorms developed across southern and central Minnesota during the mid-afternoon hours north of a warm front that extended east from a surface low over southwest Minnesota across southwest Wisconsin. Synoptic-scale lift and destabilization over the genesis region was provided by a shortwave trough moving across northern Minnesota, in concert with low-level convergence associated with a 30-35 kt 850 mb low-level jet over Iowa. The airmass south of the surface warm front over Iowa was very warm and moist with temperatures generally in the low to mid 90s and surface dew points in the lower 70s. Despite boundary layer CAPES of at least 3500 J/kg, the airmass south of the front over Iowa was strongly capped with 700 mb temperatures around +12 degrees C.
Farther north, thunderstorms were being fed by a steady supply of very unstable air transported northward across the warm front and ahead of the shortwave trough over central Minnesota, where steep mid-level lapse rates of around 8 degrees C/Km were observed. The mid-level instability was forecast to advect east into central and southern Wisconsin during the late evening. Deep layer shear was also in place over the mesoscale convective system (MCS) genesis region where winds were observed to veer from 240 at 30 knots at 850 mb, to about 270 at 65 knots at 500 mb over central and southern Minnesota. Indeed, the initial thunderstorms that developed over Minnesota during the mid- to late afternoon hours were supercellular, spawning several tornadoes. These storms were able to tap the vorticity-rich boundary layer just north of the surface warm front. The storms continued to move southeast, north of the surface warm front, into western and central Wisconsin by 00Z June 12 (7 pm CDT on June 11) and evolved into a large damaging wind-producing bow echo that raced across east central Wisconsin between 00Z and 05Z on June 12 (7 pm through midnight on June 11).
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I’ll post more observations and some links to pictures in future messages.
-George

[WisconsinF5]

Ok, now for some personal stories and pictures from this storm.

http://home.new.rr.com/awfrailroadco/stormstuff/stormdamage%206-11-01%201.jpg
http://home.new.rr.com/awfrailroadco/stormstuff/stormdamage%206-11-01%202.jpg
These two pictures show the remains of our huge silver maple tree in the front yard. Note that the limbs which have been destroyed are wrapped back around the tree trunk; they initially faced the spot where I am standing. They were not small limbs, the bottom one was approximately 1 ½’ in diameter. I was going between the front and back windows of our house with a spotlight during the storm, and watched this tree simply “snap and wrap”. My wife (stormywi) was already in the basement, and seeing the tree convinced me to beat feet and join her (Mind you, I almost never go down there).

While down there, we heard the trees from the backyard strike the house…when I went up to check out the thumps I saw that we had water streaming in the dining room window, which had both the interior and storm panes closed. Between the panes was solid water, like looking into a fish tank.

Eventually it calmed down enough that we were able to return upstairs and survey the damage, but it still stormed the rest of the night.

We were without electric service for 3 days (the aforementioned tree took out the line), no cable TV or cable internet for a week (it was terrible!! lol).

I presented some of the photos I took of the damage to a Texas/Oklahoma stormchaser group and asked for an assessment of wind speed…they asked me which tornado the pictures were from. They (along with another chaser) estimated the damage at F2-F3, which of course is well in excess of the “official” NWS wind speed.

This is a picture of a nearby park, which is (was?) known for its many large trees of all varieties. I forget what the percentage was, but they lost a sizable quantity in the storm.

http://home.new.rr.com/awfrailroadco/stormstuff/stormdamage%206-11-01%20southpark1.jpg

I do have more pics which I will post links to as I have the time.

Hope everyone enjoyed has enjoyed this so far….

-George

[WisconsinF5]

no idea why those hyperlinks didn't work in that last post...sorry.

-George

[pojo]

Let me comment about the large passing of thunderstorms on that particular night.

I had to work that night at WFRV TV 5 in Green Bay and was watching the progress of the thunderstorms. At around 845pm, I talked with the chief meteorologist and noticed via the radar, how complex this line of thunderstorms was. I talked with the director and thankfully, we had another floor director working along side of me. The director okayed my leave just as long as one of the other camera personnal was available for floor directing, which he was.

I left immediately (9pm) and had a 35 minute drive to Menasha, WI (which is just south of Appleton) because my dad was at work and all the windows were open. (During that time frame, we lived in a Mobile Home park and due to the situation, that is the worse place to be when storms of this potential grace the area.) From my drive down Highway 41, I was able to see the numerous lightning strikes across the horizon amongst the cloud to ground strikes. Thunder was atrious at times, practically bursting my ear drums. The wind wasn't as bad at the moment, but things were bound to pick up.

When I got to Darboy, WI (which is 5 minutes from my house and on the SE side of Appleton), It downpoured in sheets, upon sheets of rainfall. Here's a good idea of how bad it rained. Think of dense, dense fog. I couldn't see 1/4 mile in front of me, yet alone turn my windshield wipers on high enough to see. After stopping a few times and then following a semi (for shielding) I made it home and rushed into the house. But not before getting a little wet. I had a white t-shirt on also (wet t-shirt contest!) The wind was unbareable...I had fun running to the front door! (just think of the live shots during category 1 hurricanes...that is how bad the situation was!)

I flipped the lights on and ran around the house like a chicken with its head cut off trying to close all the windows. I managed to do so, and then was able to wipe up the puddles upon puddles of water under the windows. I went through 4 bath towels just wiping up the puddles of water!

Just as I turned on the WFRV 10pm news, the power went out! Yes, lights out. pitch black. I was able to find candles and matches that way I could find my way around the house. I called my dad at work via my cell phone (but that was on low battery, so I had left him a message to call back asap.) Thankfully, the home phone was working (I didn't know at the time, because cable and power was out.) Dad managed to call back within a 1/2 hour and I told him about the situation at home and that I was under candle light and just having an interesting time watching the progress of the storms.

From the candlelight and the sparks of lightning, I was able to watch the clouds rotate above our house. (Seriously, I wasn't really scared, but my adrenline was quite high! I thought to myself, this is awesome!) The sirens went off, but because I knew how the clouds were moving and where the rotating cells were, I stayed where I was. The tralier was shaking and rattling! But it still managed to stay stable as possible and to NOT fall off the supports.

When it was just sprinkling out I walked out to my car to grab my travel clock that way I could have an alarm for the morning (I had to work the next day at 7:30am). My dad got me up when he got home from work (6am) and we talked about the storms. When I woke up, my clock was still out. No power yet.

On my drive to work, the damage that I saw was unbelievable. It looked like something out of a movie! I came to the intersection right in front of my work and realized that the power was out at work...there was no vehicles in the parking lot, no stop lights, etc.

I drove over to my mom's to see how the house spared during last night's storms. Branches were down everywhere, power lines were mixed in with the branches, but everything else seemed ok. My step-dad and brother were home cleaning up the mess all over the yard. Siding was dented, shingles were torn off, branches all over the yard, apples came down everywhere! (we have an apple tree in the backyard) . Come to find out, the corner flooded again (it frequently does...we are 3 houses from a street corner) which caused water in the basement. Thankfully, it was contained to the crawl space, so nothing really was damaged.

I then drove back over to my dad's to help our neighbors in the clean up efforts. Siding was dented, shingles were ripped off, branches all over the yard.

The power was out for about 72 hours, cable for 80 hours. Needless to say, we had to resort to the old fashion way of entertaining ourselves for that time period.

[pojo]

continuation, Round 2 happened on 6-12-01, but they weren't as bad. It just made the clean-up situation worse.