November 12, 2005 Iowa Tornado Outbreak
Click on Pick Below to Watch Short Sample Video (~10 MB):
Jim Bishop and Mark McGowan documented multiple low-topped supercells, 4 tornadoes (one large , destructive F2 tornado), high winds and hail across Western and Central Iowa Saturday afternoon.
Jim and McGowan left Houston, TX at 3pm on Friday November 11, 2005. A strengthening shortwave trough was forecasted to move across the Central Plains during the day Saturday; a decent chance for the formation of low-topped supercells and tornadoes seemed possible across Western and Central Iowa during the late afternoon on Saturday. Jim had been anticipating this system all week, but knew the risk involved - it may not pan out. They made a pit-stop in Norman and continued to Central Iowa.
By noon on Saturday they reached Des Moines and turned west on I-80. Simon was nowcasting for them and advised them to get off near exit 40 and wait for storms to fire near the Nebraska/Iowa border.
Storms fired and raced to the northeast at nearly 50 mph. Jim drove north on state highway 173 ahead of one of the first supercells. There were several by this time, but none were tornadic. The chasers went east on 44 at Kimbalton and drove through a heavy rain core, the forward flank of one supercell. They went passed the Audubon/Guthrie county line and turned north on a road towards Coon Rapids. In Coon Rapids Jim caught up to a tornadic storm.
West of town they spooted definite rotation at cloud base. Jim initially assumed it was the RFD gustfront given it's flat and elongated appearance. Suddenly strong downdraft (RFD) winds pounded Jim and Mark and a mesocyclone formed (the order of these processes is unique to low-topped supercells). A funnel formed and soon became a tornado. They got back in the car and took a road north out of town and documented a beautiful quite rope tornado for about 2 minutes just north of Coon Rapids. They stair-stepped their way with the storm as it continued northeastward.
They drove east on a road through Dana, and then Simon advised them to drive north towards Fraser. At this point in time the storm was about to move through Stratford and was too far to the northeast to catch before dark. Simon told Jim about another storm which had just crossed over I-80 and was headed straight for Gilbert. Simon told Jim to blast east non-stop and fly south on 69 to Gilbert where he should see a tornado. Jim did just that and planned to drive towards Gilbert until he saw a meso to the southwest.
He drove through the forward flank (heavy rain) very quickly. Upon emerging from the rain a large bowl meso was clearly visible to the southwest with the RFD clear slot clear rapping around the meso. "Tornado, tornado!", Jim yelled even before anything had touched the ground. Seconds later a funnel rapidly formed and quickly spun to the ground, all in a matter of seconds. Once the rain let up Jim got out of the car to continue video taping.
As Jim watched the tornado in amazement he didn't leave the side of the car. He stood in-between the door and the front seat, leering over the roof. Are we in the path of the tornado? To Jim it didn't appear likely, but it was going to be close, so he wanted to be within seconds of the accelerator just in case.
The tornado approached them rapidly, first as a skinny gray cone. Then it grew into a dark, ominous stove-pipe tornado. The sound was incredible, like standing next to a raging waterfall and a jet engine at the same time. Jim could see debris rapping around the bottom of the condensation funnel. He kept on saying, "Oh my God, Oh my God", in complete amazement. The tornado was now only a few hundred yards to his west-southwest. The inflow winds soaring into the tornado were strong, probably 30-40 mph sustained, making it VERY difficult to hold the camera steady. For Jim this was an incredible moment.
For a few moments Jim realized that clearly him and Mark were not in the path. Jim them made that verbal on video (the mind thinks way before the mouth speaks!), and closed the car door to better shoot video of this amazing tornado! It seemed to peak in intensity right about when it became due west of their location. It crossed a country road and went through a line of power poles, and transformers exploded all over the base of the tornado. By this time the tornado was incredibly loud and Jim could hear the tornado destroying a structure as debris flew around the base of the tornado once again and power flashes lit up the base of the tornado. This was one of the most incredible things one could every witness from only a few hundred yards distance.
Then like the flick of a switch the tornado lost almost all it's intensity and dissipated rapidly. Jim continued to shoot video as there was still a tornadic circulation in the field moving rapidly northeast towards highway 69. The storm had just used up nearly all the CAPE within the local environment, and would have to move further eastward into an area of more CAPE before producing the next tornado.
Jim and Mark got back in the car and hauled it north after the storm. Sure enough within about 30 seconds the circulation touched back down on the road to the north. Jim shot some shaky video of the rope tornado which was then on the ground for about 1 minute (could be thought of as the same tornado). Upon reaching E19? they turned east. They stopped to look at the map when suddenly Jim saw a roof ((?) possibly to a barn) shoot straight up in the air about 200 yards up the road! Then to their northeast and even closer a debris cloud had formed and a funnel was forming! Without any time to react Jim put the car in reverse and accelerated. The debris cloud persisted and actually began to move west towards Jim and Mark (briefly). Jim grabbed the video camera and captured what he could. The tornado then moved north and quickly dissipated.
They continued east, crossed I-35 and stopped in Roland. Looking north-northeastward about 6 miles near Garden City they witnessed a nighttime stove-pipe tornado. And the chase was over.
Jim and Mark drove straight back to Norman and slept for a few hours. On Sunday Jim fed the video into the Stormgasm super computer. Jim and Mark left Norman at 4pm and arrived back in Houston at about midnight. Jim made it to work the following morning (4:30am!). Finally, Jim got his 2005 tornado.
Touch down Jim!